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Sample records for ignition takes place

  1. Taking place, screening place

    DEFF Research Database (Denmark)

    Hansen, Kim Toft; Waade, Anne Marit

    2019-01-01

    We introduce location studies as a new empirical approach to screen studies. Location studies represent an interdisciplinary perspective, including media, aesthetics and geography, and reflect a growing interest in places in a global media and consumption culture. The chapter analyses two recent......) with one being traditional and the other being commercial; both dramas include discussions of localities and social heritage, and both use local sports as a common metaphor for social cohesion; and both series have been partly funded by a local film Danish commissioner. However, The Legacy is shot...... to a large extent in studios, while Norskov is shot entirely on location. The study is based on interviews with producers, broadcasters, location scouts, production designers and writers, as well as quantitative and qualitative textual analyses of television drama series, the geographical places, and related...

  2. Then Daddy Takes His Place in an Australian Landscape

    OpenAIRE

    ERIN GAYLE CROUCH

    2018-01-01

    This writing accompanies a 62 minute, single channel, digital film work also titled Then Daddy Takes His Place in an Australian Landscape. The research considers themes of loss and disorientation in the above film and the film practice of Belgian filmmaker Chantal Akerman. Formally, the following writing interweaves critical engagements with Akerman’s films including No Home Movie (2015), Jeanne Dielman, 23 Commerce Quay, 1080 Brussels(1975), Là Bas (2006), with personal stories and reflecti...

  3. Mathematical modeling of phase interaction taking place in materials processing

    International Nuclear Information System (INIS)

    Zinigrad, M.

    2002-01-01

    The quality of metallic products depends on their composition and structure. The composition and the structure are determined by various physico-chemical and technological factors. One of the most important and complicated problems in the modern industry is to obtain materials with required composition, structure and properties. For example, deep refining is a difficult task by itself, but the problem of obtaining the material with the required specific level of refining is much more complicated. It will take a lot of time and will require a lot of expanses to solve this problem empirically and the result will be far from the optimal solution. The most effective way to solve such problems is to carry out research in two parallel direction. Comprehensive analysis of thermodynamics, kinetics and mechanisms of the processes taking place at solid-liquid-gaseous phase interface and building of the clear well-based physico-chemical model of the above processes taking into account their interaction. Development of mathematical models of the specific technologies which would allow to optimize technological processes and to ensure obtaining of the required properties of the products by choosing the optimal composition of the raw materials. We apply the above unique methods. We developed unique methods of mathematical modeling of phase interaction at high temperatures. These methods allows us to build models taking into account: thermodynamic characteristics of the processes, influence of the initial composition and temperature on the equilibrium state of the reactions, kinetics of homogeneous and heterogeneous processes, influence of the temperature, composition, speed of the gas flows, hydrodynamic and thermal factors on the velocity of the chemical and diffusion processes. The models can be implemented in optimization of various metallurgical processes in manufacturing of steels and non-ferrous alloys as well as in materials refining, alloying with special additives

  4. Does olfactory specific satiety take place in a natural setting?

    Science.gov (United States)

    Fernandez, P; Bensafi, M; Rouby, C; Giboreau, A

    2013-01-01

    Olfactory-specific satiety (OSS) is characterized by a specific decrease in the odor pleasantness of a food eaten to satiety or smelled without ingestion. The usual protocol for studying OSS takes place in laboratory, a setting rather removed from the real world. Here, we set out to examine OSS in a natural setting: during a meal in a restaurant. We hypothesized that an aroma contained in a food that is eaten at the beginning of a meal decreases the pleasantness of the flavor of a food with the same aroma eaten at the end of the meal. In the first experiment (Experiment 1), a test group received an appetizer flavored with a test aroma (anise) at the beginning of the meal. After the main dish, they received a dessert flavored with the same aroma. A control group received the same aromatized dessert, but after a non-aromatized appetizer. This experiment was replicated (Experiment 2) using verbena as the test aroma. For both experiments, results revealed that aroma pleasantness, but not intensity or familiarity, significantly decreased in the test groups vs. the control groups. These findings extend the concept of OSS to a realistic eating context. Copyright © 2012 Elsevier Ltd. All rights reserved.

  5. Key European Grid event to take place in Geneva

    CERN Multimedia

    2006-01-01

    EGEE'06 is the main conference of the EGEE project, which is co-funded by the European Union and hosted by CERN. More than 90 partners all over Europe and beyond are working together in EGEE to provide researchers in both academia and industry with access to major computing resources, independent of their geographic location. The largest user community of the EGEE Grid is the High-Energy Physics community and in particular the LHC experiments, which are already making heavy use of the infrastructure to prepare for data taking. However, with the many new challenges faced by EGEE in its second phase that started in April this year, an even broader audience than at previous EGEE conferences is expected. In particular, a large number of related Grid projects will feature prominently in both plenary and parallel sessions during the 5 days of this event. Industry will also be well represented, highlighting the EGEE project's commitment to technology transfer to industry. CERN is the host of the conference, which i...

  6. 4th openlab Board of Sponsors Meeting takes place at CERN on July 6, 2005

    CERN Multimedia

    Patrice Loïez

    2005-01-01

    The 4th openlab Board of Sponsors Meeting is taking place at CERN, room 513, 1-024, the 6th July 2005. The meeting will open with an Executive Session in the presence of Dr. Robert Aymar, Director General of CERN

  7. Waste Disposal: Processes Taking Place (on the way) from the Repository to the Biosphere

    International Nuclear Information System (INIS)

    Put, M.

    2000-01-01

    The main objective of SCK-CEN's R and D programme on the processes taking place on the way from the repository to the biosphere is to provide reliable and defensible models and parameters on the migration of dissolved radionuclides and gases through the host formation (Boom Clay) and the backfill materials of a deep geological repository for high level radioactive waste. The programme and main achievements in this topical area in 1999 are summarised

  8. Analytical solutions for prediction of the ignition time of wood particles based on a time and space integral method

    NARCIS (Netherlands)

    Haseli, Y.; Oijen, van J.A.; Goey, de L.P.H.

    2012-01-01

    The main idea of this paper is to establish a simple approach for prediction of the ignition time of a wood particle assuming that the thermo-physical properties remain constant and ignition takes place at a characteristic ignition temperature. Using a time and space integral method, explicit

  9. Diffusion mechanisms taking place at the early stages of cobalt deposition on Au(111)

    International Nuclear Information System (INIS)

    Oviedo, O A; Leiva, E P M; Mariscal, M M

    2008-01-01

    In the present work a detailed atomic-level analysis of some of the main diffusion mechanisms which take place during cobalt adatom deposition are studied within atom dynamics (AD) and the nudged elastic band (NEB) method. Our computer simulations reveal a very fast exchange between Co and Au atoms when the deposit is a single cobalt adatom. However, when the nucleus size increases, a decrease in the exchange probability is observed. Activation energies for different transitions are obtained using AD in combination with the NEB method

  10. Ignition of mercury-free high intensity discharge lamps

    International Nuclear Information System (INIS)

    Czichy, M; Mentel, J; Awakowicz, P; Hartmann, T

    2008-01-01

    To achieve a better understanding of the ignition behaviour of D4 lamps for automotive headlights the ignition of mercury-free metal iodide test lamps characterized by a high xenon pressure, a small electrode distance and small electrode-wall distances is investigated. The ignition of these lamps is dominated by a high voltage requirement. Nevertheless lamps are found that show a surprisingly low ignition voltage. Electrical measurements and simultaneous optical observations of the ultra-fast streamer processes show that the breakdown takes place in two different modes. One of the ignition modes which requires a high ignition voltage is characterized by a breakdown in the volume between the electrode tips. The other mode is characterized by streamer discharges along the wall. In this case the cathode, its base and the wall around is involved in the ignition process and the lamp breaks down at low voltages

  11. DETERMINING THE FEATURES OF SPORTSWEAR TAKING PLACE IN FAST FASHION COLLECTIONS

    Directory of Open Access Journals (Sweden)

    Birsen ÇİLEROĞLU

    2014-07-01

    Full Text Available Spor ts occupies the first place among most siginificant factors increasing quality of life . It has b ecome difficult to allocate proper time for sports in the course of heavy work pace and flow of life . Such circumstances have led people to increase minor sport activities which could be done during short times allocated from daily living, thus, orienting people‟s clothing preference towards sportswear . The feeling of easiness and comfort sportswear offer to individuals enhances further such preference . The feeling of comfort individuals feel in their clothing depends on the presence of physiologic and psy chologic coherence between their bodies and environment . Demand for sportswear allowing easy - movement increased upon rise in life dynamism and standards, it began to be preferred regarding comfort of use and to take its place in daily clothing, too, define d as “casual” clothing . Spor tswear being preferred very much ; has caused the firms making and producing fashion and clothing design to give place in their collections to sportswear category . Particularly, in firms where model and clothing varieties are pl enty and new model design is made in short intervals, named as, “fast fashion” , tendency towards sportswear is growing increasingly . The sale rates of sportswear, utilization rates of which are growing increasingly, has maximum value among total clothing s ales in E - business field, too. In this research, it has been aimed to determine the features of sportswear taking place in “fast fashion” clothing collections . In order to accomplish this aim, 2014 collections of four different brands taking place in natio nal and international markets have been examined through visual analysis method . In the examinations; sportswear styles of the brand, model and style differences between brands and states of using 2014 fashion trends have been taken into account. The data obtained at the end of the analyses made have been

  12. Modelling piloted ignition of wood and plastics

    International Nuclear Information System (INIS)

    Blijderveen, Maarten van; Bramer, Eddy A.; Brem, Gerrit

    2012-01-01

    Highlights: ► We model piloted ignition times of wood and plastics. ► The model is applied on a packed bed. ► When the air flow is above a critical level, no ignition can take place. - Abstract: To gain insight in the startup of an incinerator, this article deals with piloted ignition. A newly developed model is described to predict the piloted ignition times of wood, PMMA and PVC. The model is based on the lower flammability limit and the adiabatic flame temperature at this limit. The incoming radiative heat flux, sample thickness and moisture content are some of the used variables. Not only the ignition time can be calculated with the model, but also the mass flux and surface temperature at ignition. The ignition times for softwoods and PMMA are mainly under-predicted. For hardwoods and PVC the predicted ignition times agree well with experimental results. Due to a significant scatter in the experimental data the mass flux and surface temperature calculated with the model are hard to validate. The model is applied on the startup of a municipal waste incineration plant. For this process a maximum allowable primary air flow is derived. When the primary air flow is above this maximum air flow, no ignition can be obtained.

  13. [Marketing approval and market surveillance of medical devices in Germany: Where does policy integration take place?].

    Science.gov (United States)

    Lang, Achim

    2014-01-01

    Since 2011 new regulatory measures regarding medical devices have been set up with the aim to eliminate obstacles to innovations and to find more coordinated ways to marketing authorisation and market surveillance. This essay investigates whether these new and existing coordination mechanisms build up to a Joined-up Government approach. The analysis shows that the regulatory process should be adjusted along several dimensions. First, many organisations lack awareness regarding their stakeholders and focus solely on their immediate organisational activities. Second, the regulatory process (marketing authorisation and market surveillance) is too fragmented for an effective communication to take place. Finally, the underlying strategy process is an ad-hoc approach lacking continuity and continued involvement of, in particular, the responsible federal ministries. Copyright © 2013. Published by Elsevier GmbH.

  14. What it Takes to Successfully Implement Technology for Aging in Place: Focus Groups With Stakeholders.

    Science.gov (United States)

    Peek, Sebastiaan Theodorus Michaël; Wouters, Eveline J M; Luijkx, Katrien G; Vrijhoef, Hubertus J M

    2016-05-03

    There is a growing interest in empowering older adults to age in place by deploying various types of technology (ie, eHealth, ambient assisted living technology, smart home technology, and gerontechnology). However, initiatives aimed at implementing these technologies are complicated by the fact that multiple stakeholder groups are involved. Goals and motives of stakeholders may not always be transparent or aligned, yet research on convergent and divergent positions of stakeholders is scarce. To provide insight into the positions of stakeholder groups involved in the implementation of technology for aging in place by answering the following questions: What kind of technology do stakeholders see as relevant? What do stakeholders aim to achieve by implementing technology? What is needed to achieve successful implementations? Mono-disciplinary focus groups were conducted with participants (n=29) representing five groups of stakeholders: older adults (6/29, 21%), care professionals (7/29, 24%), managers within home care or social work organizations (5/29, 17%), technology designers and suppliers (6/29, 21%), and policy makers (5/29, 17%). Transcripts were analyzed using thematic analysis. Stakeholders considered 26 different types of technologies to be relevant for enabling independent living. Only 6 out of 26 (23%) types of technology were mentioned by all stakeholder groups. Care professionals mentioned fewer different types of technology than other groups. All stakeholder groups felt that the implementation of technology for aging in place can be considered a success when (1) older adults' needs and wishes are prioritized during development and deployment of the technology, (2) the technology is accepted by older adults, (3) the technology provides benefits to older adults, and (4) favorable prerequisites for the use of technology by older adults exist. While stakeholders seemed to have identical aims, several underlying differences emerged, for example, with regard

  15. Model of Wagons’ Placing-In and Taking-Out Problem in a Railway Station and Its Heuristic Algorithm

    Directory of Open Access Journals (Sweden)

    Chuijiang Guo

    2014-01-01

    Full Text Available Placing-in and taking-out wagons timely can decrease wagons’ dwell time in railway stations, improve the efficiency of railway transportation, and reduce the cost of goods transportation. We took the locomotive running times between goods operation sites as weights, so the wagons’ placing-in and taking-out problem could be regarded as a single machine scheduling problem, 1pijCmax, which could be transformed into the shortest circle problem in a Hamilton graph whose relaxation problem was an assignment problem. We used a Hungarian algorithm to calculate the optimal solution of the assignment problem. Then we applied a broken circle and connection method, whose computational complexity was O(n2, to find the available satisfactory order of wagons’ placing-in and taking-out. Complex problems, such as placing-in and transferring combined, taking-out and transferring combined, placing-in and taking-out combined, or placing-in, transferring, and taking-out combined, could also be resolved with the extended algorithm. A representative instance was given to illustrate the reliability and efficiency of our results.

  16. Subsurface nitrate reduction under wetlands takes place in narrow superficial zones

    DEFF Research Database (Denmark)

    dos Santos Ribas, Osmar; Calderer, M.; Marti, Vicens

    2017-01-01

    This study aims to investigate the depth distribution of the Nitrate Reduction Potential (NRP) on a natural and a re-established wetland. The obtained NRP provides a valuable data of the driving factors affecting denitrification, the Dissimilatory Nitrate Reduction to Ammonium (DNRA) process and ...... that wetlands can be restored satisfactorily.......This study aims to investigate the depth distribution of the Nitrate Reduction Potential (NRP) on a natural and a re-established wetland. The obtained NRP provides a valuable data of the driving factors affecting denitrification, the Dissimilatory Nitrate Reduction to Ammonium (DNRA) process...... and the performance of a re-established wetland. Intact soil cores were collected and divided in slices for the determination of Organic Matter (OM) through Loss of Ignition (LOI) as well as Dissolved Organic Carbon (DOC) and NRP spiking nitrate in batch tests. The Nitrate Reduction (NR) was fitted as a pseudo...

  17. Taking back place-names – from dusty library to digital life

    DEFF Research Database (Denmark)

    Knudsen, Bo Nissen

    Danish place-names have been under publication since 1922 in the scientific series Danmarks Stednavne (Place-Names of Denmark) but only recently the huge project of a digitization of the series has been undertaken. Around 120,000 name articles are now on their way to the web as part of the Digital...... atlas of the Danish historical-administrative geography. Digitization and presentation of a scientific place-names edition poses many interesting problems in itself, especially regarding the variation over time in both the selection of names and the build-up of scholarly knowledge. How are we to convey...... mobility of the book format into a digital context – by making the content available as an application for mobile devices such as smart phones and iPads? Adding geocodes to the name articles could open up the possibility of a digital place-name lexicon allowing the end user to move around in a place...

  18. DSC studies of retrogradation and amylose-lipid transition taking place in gamma-irradiated wheat starch

    International Nuclear Information System (INIS)

    Ciesla, K.; Gluszewski, W.; Eliasson, A.C.

    2006-01-01

    It has been already shown that degradation resulting from gamma irradiation induces a decrease in order of starch granules and influences gelatinisation taking place during heating of starch and flour suspensions. In presented paper, DSC (differential scanning calorimetry) studies were carried out for wheat starch, non-irradiated and irradiated using doses in the range from 5 to 30 kGy. The influence of the conditions applied during DSC measurements on the possibility to observe differences between the amylose-lipid complex transition and retrogradation taking place in the non-irradiated and particularly irradiated starch samples was checked. The better differentiation between the amylose-lipid complex transition taking place in particular samples accompanied by the better reproducity were obtained in the case of dense suspensions as compared to the watery suspensions as well as during the first analysis performed for the recrystallised gels

  19. What it takes to successfully implement technology for aging in place: focus groups with stakeholders

    NARCIS (Netherlands)

    Eveline J.M. Wouters; Katrien G. Luijkx; Hubertus J.M. Vrijhoef; Sebastiaan Theodorus Michaël Peek MSc

    2016-01-01

    BACKGROUND: There is a growing interest in empowering older adults to age in place by deploying various types of technology (ie, eHealth, ambient assisted living technology, smart home technology, and gerontechnology). However, initiatives aimed at implementing these technologies are complicated by

  20. Advice from Rural Elders: What It Takes to Age in Place

    Science.gov (United States)

    Dye, Cheryl J.; Willoughby, Deborah F.; Battisto, Dina G.

    2011-01-01

    Older adults prefer to age in place (AIP), and there are psychological, physiological, and economic benefits in doing so. However, it is especially challenging to AIP in rural communities. AIP models have been tested in urban settings and age-segregated communities, but they are not appropriate for rural communities. This paper presents rural AIP…

  1. DETERMINING THE FEATURES OF SPORTSWEAR TAKING PLACE IN FAST FASHION COLLECTIONS

    OpenAIRE

    ÇİLEROĞLU, Birsen; KIVILCIMLAR, İnci

    2015-01-01

    Sports occupies the first place among most siginificant factors increasing quality of life. It has become difficult to allocate proper time for sports in the course of heavy work pace and flow of life. Such circumstances have led people to increase minor sport activities which could be done during short times allocated from daily living, thus, orienting people’s clothing preference towards sportswear. The feeling of easiness and comfort sportswear offer to individuals enhances further such pr...

  2. Beyond stereotypes of adolescent risk taking: Placing the adolescent brain in developmental context

    Directory of Open Access Journals (Sweden)

    Daniel Romer

    2017-10-01

    Full Text Available Recent neuroscience models of adolescent brain development attribute the morbidity and mortality of this period to structural and functional imbalances between more fully developed limbic regions that subserve reward and emotion as opposed to those that enable cognitive control. We challenge this interpretation of adolescent development by distinguishing risk-taking that peaks during adolescence (sensation seeking and impulsive action from risk taking that declines monotonically from childhood to adulthood (impulsive choice and other decisions under known risk. Sensation seeking is primarily motivated by exploration of the environment under ambiguous risk contexts, while impulsive action, which is likely to be maladaptive, is more characteristic of a subset of youth with weak control over limbic motivation. Risk taking that declines monotonically from childhood to adulthood occurs primarily under conditions of known risks and reflects increases in executive function as well as aversion to risk based on increases in gist-based reasoning. We propose an alternative Life-span Wisdom Model that highlights the importance of experience gained through exploration during adolescence. We propose, therefore, that brain models that recognize the adaptive roles that cognition and experience play during adolescence provide a more complete and helpful picture of this period of development.

  3. Understanding Where Americas Public Discussion Takes Place In Todays Society: Case Studies of Concealed Weapons Carry Reform

    Science.gov (United States)

    2016-06-01

    arguing that concealed carry permit holders are a danger to public safety and that mass shootings are taking place by citizens who are legally armed.2...who worked at an abortion clinic that had recently been bombed and whose life had been threatened was denied a license to carry because he was not...populace. The new law laid out new prohibitions and penalties enforceable statewide. Additionally, the Preemption Act was necessary to set the legal

  4. Coronavirus and influenza virus proteolytic priming takes place in tetraspanin-enriched membrane microdomains.

    Science.gov (United States)

    Earnest, James T; Hantak, Michael P; Park, Jung-Eun; Gallagher, Tom

    2015-06-01

    Coronaviruses (CoVs) and low-pathogenicity influenza A viruses (LP IAVs) depend on target cell proteases to cleave their viral glycoproteins and prime them for virus-cell membrane fusion. Several proteases cluster into tetraspanin-enriched microdomains (TEMs), suggesting that TEMs are preferred virus entry portals. Here we found that several CoV receptors and virus-priming proteases were indeed present in TEMs. Isolated TEMs, when mixed with CoV and LP IAV pseudoparticles, cleaved viral fusion proteins to fusion-primed fragments and potentiated viral transductions. That entering viruses utilize TEMs as a protease source was further confirmed using tetraspanin antibodies and tetraspanin short hairpin RNAs (shRNAs). Tetraspanin antibodies inhibited CoV and LP IAV infections, but their virus-blocking activities were overcome by expressing excess TEM-associated proteases. Similarly, cells with reduced levels of the tetraspanin CD9 resisted CoV pseudoparticle transductions but were made susceptible by overproducing TEM-associated proteases. These findings indicated that antibodies and CD9 depletions interfere with viral proteolytic priming in ways that are overcome by surplus proteases. TEMs appear to be exploited by some CoVs and LP IAVs for appropriate coengagement with cell receptors and proteases. Enveloped viruses use their surface glycoproteins to catalyze membrane fusion, an essential cell entry step. Host cell components prime these viral surface glycoproteins to catalyze membrane fusion at specific times and places during virus cell entry. Among these priming components are proteases, which cleave viral surface glycoproteins, unleashing them to refold in ways that catalyze virus-cell membrane fusions. For some enveloped viruses, these proteases are known to reside on target cell surfaces. This research focuses on coronavirus and influenza A virus cell entry and identifies TEMs as sites of viral proteolysis, thereby defining subcellular locations of virus

  5. Let us play: (unshackling liaisons, (unmasking games and (unhindered dialogue in the arena where theology takes place

    Directory of Open Access Journals (Sweden)

    Tanya van Wyk

    2017-10-01

    Full Text Available This contribution is a political-theological and hermeneutical reflection on the origin, nature, intention and contribution of a research theme identified within the dynamics of an institutional space, by taking a critical look at the �rules� and the �game� of university academia. Specific reference is made to institutional and faculty research themes, namely �reconciling diversity� and �Ecodomy � life in its fullness�. The institutional academic space is compared to a Hunger Games-style panopticon, with its �rules� and �play�. It is argued that these research themes can only make an authentic contribution if the �play� and �game�of the space in which these themes originate, are deconstructed. If this deconstruction can take place, there might be an authentic chance for unhindered dialogue towards the transformation of the academic space and the greater community it serves.

  6. The albedo problem in the case of multiple synthetic scattering taking place in a plane-symmetric slab

    International Nuclear Information System (INIS)

    Shafiq, A.; Meyer, H.E. de; Grosjean, C.C.

    1985-01-01

    An approximate model based on an improved diffusion-type theory is established for treating multiple synthetic scattering in a homogeneous slab of finite thickness. As in the case of the exact treatment given in the preceding paper (Part I), it appears possible to transform the considered transport problem into an equivalent fictitious one involving multiple isotropic scattering, therefore permitting the application of an established corrected diffusion theory for treating isotropic scattering taking place in a convex homogeneous medium bounded by a vacuum in the presence of various types of sources. The approximate values of the reflection and transmission coefficients are compared with the rigorous values listed in Part I. In this way, the high accuracy of the approximation is clearly demonstrated. (author)

  7. DSC Studies of Retrogradation and Amylose-Lipid Complex Transition Taking Place in Gamma Irradiated Wheat Starch

    International Nuclear Information System (INIS)

    Ciesla, K.

    2006-01-01

    Degradation resulting from gamma irradiation induces decrease in order of starch granules and influences the processes occurring in starch-water system. Differential scanning calorimetry (DSC) was applied at present for studying the effect of radiation with doses of 5 - 30 kGy on amylose-lipid complex transition and retrogradation occurring in wheat starch gels. Influence of the conditions applied during DSC measurements and intermediate storage was tested on the possibility to observe radiation effect. Wheat starch was irradiated with 60 C o gamma rays in a gamma cell Issledovatiel placed in the Department of Radiation Chemistry, INCT. DSC measurements were performed for ca. 50% and ca. 20% gels during heating - cooling - heating cycles (up to 3 cycles) in the temperature range 10 - 150 degree at heating and cooling rates of 10, 5 and 2.5 degree min - 1. The Seiko DSC 6200 calorimeter was used. Decrease in amylose-lipid complex transition temperature was found already after irradiation of wheat starch with a dose of 5 kGy showing modificatin of the complex structure. The differences between the irradiated and the non-irradiated samples became the easier seen in the every foregoing heating or cooling cycle as compared to the preceeding one. It is because that thermal treatment causes decrease of transition temperature in all the irradiated samples, with no effect or increase of that temperature observed in the non-irradiated ones. Irradiation hinders retrogradation taking place in ca. 50% gels but facilitates retrogradation occurring in ca. 20 % gels. Moreover, the expanded differences between the amylose-lipid complex formed in the irradiated and non-irradiated gels result due to their recrystallisation. Storage of the gels induces decrease in the temperature of the complex transition as compared to the last cycle of the first analysis. That decrease was, however, more significant in the case of all the irradiated samples than in the case of the initial sample. In

  8. High frequency ignition arrangement

    Energy Technology Data Exchange (ETDEWEB)

    Canup, R E

    1977-03-03

    The invention concerns an HF ignition arrangement for combustion engines with a transistor oscillator. As this oscillator requires a current of 10A, with peak currents up to about 50A, it is not sensible to take this current through the remote ignition switch for switching it on and off. According to the invention the HF high voltage transformer of the ignition is provided with a control winding, which only requires a few milliamps DC and which can therefore be switched via the ignition switch. If the ignition switch is in the 'running' position, then a premagnetising DC current flows through the control winding, which suppresses the oscillation of the oscillator which has current flowing through it, until this current is interrupted by the interruptor contacts controlled by the combustion engine, so that the oscillations of the oscillator start immediately; the oscillator only continues to oscillate during the period during which the interruptor contacts controlled by the machine are open and interrupt the premagnetisation current. The control winding is short circuited in the 'off' position of the ignition switch.

  9. Where and How Do Aging Processes Take Place in Everyday Life? Answers From a New Materialist Perspective

    Directory of Open Access Journals (Sweden)

    Grit Höppner

    2018-04-01

    Full Text Available In the last decade, the focus of studies on age and aging has fundamentally changed from biological to symbolic, discursive, and cultural phenomena. Currently, the most studied topic in material gerontology is the materiality of age and aging in the context of everyday life. Scholars in this area have thus been making an important contribution to a material understanding of aging processes. As we understand them, however, both social constructivist and material gerontological concepts reach their limit when it comes to the questions of where and how aging processes actually take place in everyday life. In order to answer these two questions, we review social constructivist ideas with a particular focus on the “doing age” concept and material gerontological assumptions regarding human subjects, their material environments, and their relations. We then suggest rethinking bodily limitations and agencies addressed by scholars in the field of new materialism. The aim is to develop a new materialist-inspired understanding of aging processes that helps to reconstruct the material-discursive co-production of aging processes. These processes are deployed as mutual entanglements of materiality and meaning as well as of humans and non-human agency. This approach emphasizes the decentralization of the human actor and thus helps to map the material-discursive complexity of aging processes as relational co-products of humans and non-humans in everyday life.

  10. Effect of experimentally observed hydrogenic fractionation on inertial confinement fusion ignition target performance

    International Nuclear Information System (INIS)

    McKenty, P. W.; Wittman, M. D.; Harding, D. R.

    2006-01-01

    The need of cryogenic hydrogenic fuels in inertial confinement fusion (ICF) ignition targets has been long been established. Efficient implosion of such targets has mandated keeping the adiabat of the main fuel layer at low levels to ensure drive energies are kept at reasonable minima. The use of cryogenic fuels helps meet this requirement and has therefore become the standard in most ICF ignition designs. To date most theoretical ICF ignition target designs have assumed a homogeneous layer of deuterium-tritium (DT) fuel kept slightly below the triple point. However, recent work has indicated that, as cryogenic fuel layers are formed inside an ICF capsule, isotopic dissociation of the tritium (T), deuterium (D), and DT takes place leading to a 'fractionation' of the final ice layer. This paper will numerically investigate the effects that various scenarios of fractionation have on hot-spot formation, ignition, and burn in ICF ignition target designs

  11. What does it take to make them stay? : how place satisfaction relates to willingness to stay of the creative class

    OpenAIRE

    Annell, Jonas; Terman, Felix

    2017-01-01

    Swedish students in smaller university host cities leave in favor of more attractive places after having completed their studies. Failing to retain newly graduated students is a problem for university host cities as educated people are associated with the group referred to as the creative class. Members of the creative class are drivers of regional economic growth, and have historically proven to be important for creating and developing the well-being of cities. Different place attributes hav...

  12. Young People Take Their Rightful Places as Full and Contributing Members of a World Class Workforce: Philadelphia Youth Network Annual Report 2006

    Science.gov (United States)

    Philadelphia Youth Network, 2006

    2006-01-01

    The title of this year's annual report has particular meaning for all of the staff at the Philadelphia Youth Network. The phrase derives from Philadelphia Youth Network's (PYN's) new vision statement, developed as part of its recent strategic planning process, which reads: All of our city's young people take their rightful places as full and…

  13. Stuck between a ROC and a hard place? Barriers to the take up of green energy in the UK

    International Nuclear Information System (INIS)

    Diaz-Rainey, Ivan; Ashton, John K.

    2008-01-01

    This paper examines the UK mechanisms for ensuring future investment in renewable energy through consumer adoption of green energy tariffs and the Renewable Obligation Certificate (ROC) system. Using a national survey and focus groups the stated willingness by UK customers to pay a premium for renewable or green energy and actual take up of such tariffs is assessed. Substantial differences between willingness to pay for and the adoption of green energy tariffs are reported. This disparity is linked to a range of factors including consumer confusion, lack of supply, complexities of constructing 'green source' tariffs under the ROC system and a lack of customer trust. It is concluded that the re-definition of the green energy market in favour of 'green source' tariffs, greater direct compliance with the Renewable Obligation by addressing supply constraints, and efforts in providing clearer information and choices for consumers via a compulsory green energy accreditation scheme are required if willing consumers' are to contribute to investment in renewable energy

  14. High-frequency cold ignition of fluorescent lamps

    International Nuclear Information System (INIS)

    Haverlag, M.; Sormani, J.; Heuvelmans, J.; Geven, A.; Kaldenhoven, L.; Heijne, G.; Kraus, A.

    2002-01-01

    Experimental and theoretical investigations have been performed on the ignition process of low-pressure mercury-noble gas fluorescent lamps operating on a 50 kHz electronic driver circuit. In case the electrodes of the lamp are not heated prior to the ignition process, the ignition process can, under certain conditions, lead to premature fracture of the coiled-coil electrode, which means that the lamp ceases to operate before the emitter is consumed completely. Experimental studies of this process have shown that the erosion process responsible for this premature end-of-life consists of localized sputtering of the tungsten electrode by energetic ions from the glow discharge that is present during the ignition process. In order to understand the basic process that leads to localized sputtering of the electrodes in a glow discharge, a simple glow-discharge fluid model, in combination with a finite-element model of the heat transport in the electrode, has been built. The model shows that thermionic emission can supply a significant fraction of the electrons already at temperatures far below the normal operating temperature in fluorescent lamps. This thermionic emission is responsible for a contraction process. After the beginning of the discharge contraction it takes typically a few milliseconds before the glow-to-arc transition is observed in the lamp voltage and the normal electrode operating temperature is reached. During this time localized sputtering takes place, which eventually leads to coil fracture. (author)

  15. The Investigation of Mobbing Events Taking Place at Higher Education Institutions in Turkey Considering the Reflections on Media

    Directory of Open Access Journals (Sweden)

    Çubukçu Zühal

    2015-08-01

    considering that they are published nationally, reference newspapers and belong to different publication groups. The data used in this study was taken from the archive of the three newspapers. When the archives of the newspapers was scanned, the word “mobbing” was taken as key word for the search. In qualitative researches, newspapers are considered to be public archive and used as reference documents. The data obtained was grouped depending on the newspapers which it was taken from, on the year of publication, on where they took place, on the gender of the victims and on who the sufferers are.

  16. Ignition system for an internal combustion engine with rotary system

    Energy Technology Data Exchange (ETDEWEB)

    Hochstein, P A

    1977-05-18

    In the Wankel engine, the sparking plugs spark three times per rotation of the rotor and are never cooled by the incoming mixture. This constant high temperature environment necessitates the use of special sparking plugs. The covered top of the sparking plug is particularly liable to carbon deposits. This invention makes it possible to use sparking plugs on the rotor, without the disadvantages due to the use of high voltage. Further, the use of distributors or mechanical devices determining the ignition timing is no longer necessary. The fuel/air mixture is ignited in a combustion chamber, which is limited by first and second components moving relative to one another in repeated cycles. A generator device is fitted to the first components and an ignition device to the second components. The magnetic flux linking takes place in a predetermined area of the relative movement between the first and second components in a repeated cycle. An ignition signal is produced in the combustion chamber by the magnetic flux linking.

  17. Combustion in a High-Speed Compression-Ignition Engine

    Science.gov (United States)

    Rothrock, A M

    1933-01-01

    An investigation conducted to determine the factors which control the combustion in a high-speed compression-ignition engine is presented. Indicator cards were taken with the Farnboro indicator and analyzed according to the tangent method devised by Schweitzer. The analysis show that in a quiescent combustion chamber increasing the time lag of auto-ignition increases the maximum rate of combustion. Increasing the maximum rate of combustion increases the tendency for detonation to occur. The results show that by increasing the air temperature during injection the start of combustion can be forced to take place during injection and so prevent detonation from occurring. It is shown that the rate of fuel injection does not in itself control the rate of combustion.

  18. Analytical solutions for prediction of the ignition time of wood particles based on a time and space integral method

    International Nuclear Information System (INIS)

    Haseli, Y.; Oijen, J.A. van; Goey, L.P.H. de

    2012-01-01

    Highlights: ► A simple model for prediction of the ignition time of a wood particle is presented. ► The formulation is given for both thermally thin and thermally thick particles. ► Transition from thermally thin to thick regime occurs at a critical particle size. ► The model is validated against a numerical model and various experimental data. - Abstract: The main idea of this paper is to establish a simple approach for prediction of the ignition time of a wood particle assuming that the thermo-physical properties remain constant and ignition takes place at a characteristic ignition temperature. Using a time and space integral method, explicit relationships are derived for computation of the ignition time of particles of three common shapes (slab, cylinder and sphere), which may be characterized as thermally thin or thermally thick. It is shown through a dimensionless analysis that the dimensionless ignition time can be described as a function of non-dimensional ignition temperature, reactor temperature or external incident heat flux, and parameter K which represents the ratio of conduction heat transfer to the external radiation heat transfer. The numerical results reveal that for the dimensionless ignition temperature between 1.25 and 2.25 and for values of K up to 8000 (corresponding to woody materials), the variation of the ignition time of a thermally thin particle with K and the dimensionless ignition temperature is linear, whereas the dependence of the ignition time of a thermally thick particle on the above two parameters obeys a quadratic function. Furthermore, it is shown that the transition from the regime of thermally thin to the regime of thermally thick occurs at K cr (corresponding to a critical size of particle) which is found to be independent of the particle shape. The model is validated by comparing the predicted and the measured ignition time of several wood particles obtained from different sources. Good agreement is achieved which

  19. ENVIRONMENT PROTECTION THROUGH DETECTION OF HOT SPOTS USING THERMOGRAPHY IN COAL DEPOSITS BEFORE SELF IGNITION

    Directory of Open Access Journals (Sweden)

    Alina DINCĂ

    2009-12-01

    Full Text Available In this paper is presented a way to contribute to the environmental protection when it comes to coal which waits in big deposits to be burned for energy production. Because of certain parameters, in some places, the deposited coal could overheat and self ignite, thus loosing its caloric properties and even lead to fire. In this case the losses could be even higher, and the effect on the environment even worse. In order to prevent this self ignition to happen, an infrared camera can be mounted on a system, and the camera together with software which interprets the thermographic images, can alarm the personnel who is in charge with coal surveillance that the coal will ignite unless they take immediate measures. Also, there will be presented the limits we have found by now in the way of finalizing the application.

  20. Stability of Ignition Transients

    OpenAIRE

    V.E. Zarko

    1991-01-01

    The problem of ignition stability arises in the case of the action of intense external heat stimuli when, resulting from the cut-off of solid substance heating, momentary ignition is followed by extinction. Physical pattern of solid propellant ignition is considered and ignition criteria available in the literature are discussed. It is shown that the above mentioned problem amounts to transient burning at a given arbitrary temperature distribution in the condensed phase. A brief survey...

  1. Progress Toward Ignition on the National Ignition Facility

    International Nuclear Information System (INIS)

    Kauffman, R.L.

    2011-01-01

    yield and areal density show significant increases as a result of the optimization. The experimental Ignition Threshold Factor (ITFX) is a measure of the progress toward ignition. ITFX is analogous to the Lawson Criterion in Magnetic Fusion. Implosions have improved by over a factor of 50 since the first cryogenic layered experiments were done in September 2010. This increase is a measure of the progress made toward the ignition goal in the past year. Optimization experiments are planned in the coming year for continued improvement in implosion performance to achieve the ignition goal. In summary, NIF has made significant progress toward ignition in the 30 months since project completion. Diagnostics and all of the supporting equipment are in place for ignition experiments. The Ignition Campaign is under way as a national collaborative effort of all the National Nuclear Security Administration (NNSA) science laboratories as well as international partners.

  2. Dual coil ignition system

    Energy Technology Data Exchange (ETDEWEB)

    Huberts, Garlan J.; Qu, Qiuping; Czekala, Michael Damian

    2017-03-28

    A dual coil ignition system is provided. The dual coil ignition system includes a first inductive ignition coil including a first primary winding and a first secondary winding, and a second inductive ignition coil including a second primary winding and a second secondary winding, the second secondary winding connected in series to the first secondary winding. The dual coil ignition system further includes a diode network including a first diode and a second diode connected between the first secondary winding and the second secondary winding.

  3. When and Where Learning is Taking Place: Multisynaptic Changes in Strength During Different Behaviors Related to the Acquisition of an Operant Conditioning Task by Behaving Rats.

    Science.gov (United States)

    Fernández-Lamo, Iván; Delgado-García, José M; Gruart, Agnès

    2018-03-01

    Although it is generally assumed that brain circuits are modified by new experiences, the question of which changes in synaptic efficacy take place in cortical and subcortical circuits across the learning process remains unanswered. Rats were trained in the acquisition of an operant conditioning in a Skinner box provided with light beams to detect animals' approaches to lever and feeder. Behaviors such as pressing the lever, eating, exploring, and grooming were also recorded. Animals were chronically implanted with stimulating and recording electrodes in hippocampal, prefrontal, and subcortical sites relevant to the task. Field synaptic potentials were evoked during the performance of the above-mentioned behaviors and before, during, and after the acquisition process. Afferent pathways to the hippocampus and the intrinsic hippocampal circuit were slightly modified in synaptic strength during the performance of those behaviors. In contrast, afferent and efferent circuits of the medial prefrontal cortex were significantly modified in synaptic strength across training sessions, mostly at the moment of the largest change in the learning curve. Performance of behaviors nondirectly related to the acquisition process (exploring, grooming) also evoked changes in synaptic strength across training. This study helps to understand when and where learning is being engraved in the brain. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  4. Fusion ignition via a magnetically-assisted fast ignition approach

    OpenAIRE

    Wang, W. -M.; Gibbon, P.; Sheng, Z. -M.; Li, Y. T.; Zhang, J.

    2016-01-01

    Significant progress has been made towards laser-driven fusion ignition via different schemes, including direct and indirect central ignition, fast ignition, shock ignition, and impact ignition schemes. However, to reach ignition conditions, there are still various technical and physical challenges to be solved for all these schemes. Here, our multi-dimensional integrated simulation shows that the fast-ignition conditions could be achieved when two 2.8 petawatt heating laser pulses counter-pr...

  5. REACTION KINETICS SELF-PROPOGATION REGIME DURING PRE-IGNITION PERIOD

    Directory of Open Access Journals (Sweden)

    D. D. Polishchuk

    2015-11-01

    Full Text Available Self-propagation high temperature synthesis (SHS technological regulations application is mainly limited by transformation processes taking place in the pre-ignition period. Zn-S, Zn-Se, Ti-C and 3Ni-Al small sample systems ignition experimental study was carried out under heating conditions in inert atmosphere with temperature values T = 1200K.It was shown that at this temperature level a chemical reaction can be initiated, turning into a self-sustaining mode. Wherein the reaction limiting factors can be mass transfer processes. Ignition temperatures were determined and plotted via the samples size. A physical ignition model was developed assuming the pre-ignition period limiting reaction Arrhenius law.The inverse combustion problem solution made it possible to calculate the low-temperature (T = 800 ÷ 1200K reaction kinetic constant values. Comparison thus obtained values  with the known data of other researchers showed their good agreement.Activation energy values for the Zn-S system were used to calculate the heat wave propagation speed. This value appeared to coincide with experimental values.Obtained results analysis leads to the conclusion about the availability and justification for the proposed method of express-analysis of presupposed, but previously not studied SHS systems. The results thus obtained allow us to estimate conditions for the SHS technology implementation, the reactor characteristic sizes and the thermal wave’s propagation speed.

  6. Thin Places

    OpenAIRE

    Lockwood, Sandra Elizabeth

    2013-01-01

    This inquiry into the three great quests of the twentieth century–the South Pole, Mount Everest, and the Moon–examines our motivations to venture into these sublime, yet life-taking places. The Thin Place was once the destination of the religious pilgrim seeking transcendence in an extreme environment. In our age, the Thin Place quest has morphed into a challenge to evolve beyond the confines of our own physiology; through human ingenuity and invention, we reach places not meant to accommod...

  7. Hot Surface Ignition

    OpenAIRE

    Tursyn, Yerbatyr; Goyal, Vikrant; Benhidjeb-Carayon, Alicia; Simmons, Richard; Meyer, Scott; Gore, Jay P.

    2015-01-01

    Undesirable hot surface ignition of flammable liquids is one of the hazards in ground and air transportation vehicles, which primarily occurs in the engine compartment. In order to evaluate the safety and sustainability of candidate replacement fuels with respect to hot surface ignition, a baseline low lead fuel (Avgas 100 LL) and four experimental unleaded aviation fuels recommended for reciprocating aviation engines were considered. In addition, hot surface ignition properties of the gas tu...

  8. Reaching ignition in the tokamak

    International Nuclear Information System (INIS)

    Furth, H.P.

    1985-06-01

    This review covers the following areas: (1) the physics of burning plasmas, (2) plasma physics requirements for reaching ignition, (3) design studies for ignition devices, and (4) prospects for an ignition project

  9. Ignition delay of combustible materials in normoxic equivalent environments

    Science.gov (United States)

    Sara McAllister; Carlos Fernandez-Pello; Gary Ruff; David Urban

    2009-01-01

    Material flammability is an important factor in determining the pressure and composition (fraction of oxygen and nitrogen) of the atmosphere in the habitable volume of exploration vehicles and habitats. The method chosen in this work to quantify the flammability of a material is by its ease of ignition. The ignition delay time was defined as the time it takes a...

  10. Ignition probabilities for Compact Ignition Tokamak designs

    International Nuclear Information System (INIS)

    Stotler, D.P.; Goldston, R.J.

    1989-09-01

    A global power balance code employing Monte Carlo techniques had been developed to study the ''probability of ignition'' and has been applied to several different configurations of the Compact Ignition Tokamak (CIT). Probability distributions for the critical physics parameters in the code were estimated using existing experimental data. This included a statistical evaluation of the uncertainty in extrapolating the energy confinement time. A substantial probability of ignition is predicted for CIT if peaked density profiles can be achieved or if one of the two higher plasma current configurations is employed. In other cases, values of the energy multiplication factor Q of order 10 are generally obtained. The Ignitor-U and ARIES designs are also examined briefly. Comparisons of our empirically based confinement assumptions with two theory-based transport models yield conflicting results. 41 refs., 11 figs

  11. Ignition tuning for the National Ignition Campaign

    Directory of Open Access Journals (Sweden)

    Landen O.

    2013-11-01

    Full Text Available The overall goal of the indirect-drive inertial confinement fusion [1] tuning campaigns [2] is to maximize the probability of ignition by experimentally correcting for likely residual uncertainties in the implosion and hohlraum physics [3] used in our radiation-hydrodynamic computational models, and by checking for and resolving unexpected shot-to-shot variability in performance [4]. This has been started successfully using a variety of surrogate capsules that set key laser, hohlraum and capsule parameters to maximize ignition capsule implosion velocity, while minimizing fuel adiabat, core shape asymmetry and ablator-fuel mix.

  12. Advances for laser ignition of internal combustion and rocket engines

    International Nuclear Information System (INIS)

    Schwarz, E.

    2011-01-01

    The scope of the PhD thesis presented here is the investigation of theoretical and practical aspects of laser-induced spark ignition and laser thermal ignition. Laser ignition systems are currently undergoing a rapidly development with growing intensity involving more and more research groups who mainly concentrate on the field of car and large combustion engines. This research is primarily driven by the engagement to meet the increasingly strict emission limits and by the intention to use the limited energy reserves more efficiently. For internal combustion engines, laser plasma-induced ignition will allow to combine the goals for legally required reductions of pollutant emissions and higher engine efficiencies. Also for rocket engines laser ignition turns out to be very attractive. A highly reliable ignition system like laser ignition would represent an option for introducing non-toxic propellants in order to replace highly toxic and carcinogenic hydrazine-based propellants commonly used in launch vehicle upper stages and satellites. The most important results on laser ignition and laser plasma generation, accomplished by the author and, in some respects, enriched by cooperation with colleagues are presented in the following. The emphasis of this thesis is placed on the following issues: - Two-color effects on laser plasma generation - Theoretical considerations about the focal volume concerning plasma generation - Plasma transmission experiments - Ignition experiments on laser-induced ignition - Ignition experiments on thermally-induced ignition - Feasibility study on laser ignition of rocket engines The purpose of the two-color laser plasma experiments is to investigate possible constructive interference effects of driving fields that are not monochromatic, but contain (second) harmonic radiation with respect to the goal of lowering the plasma generation threshold. Such effects have been found in a number of related processes, such as laser ablation or high

  13. Components for more blue. BLUETEC takes away undesired nitrogen oxides and creates cleaner auto-ignition; Bausteine fuer mehr Blau. BLUETEC entfernt unerwuenschte Stickoxide und macht den Selbstzuender sauberer

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-07-01

    The success story of the diesel engine is closely linked with the history of Mercedes-Benz. Now a new chapter is opened with BLUETEC. The modular technology package that is presented by Mercedes-Benz for the first time constitutes a milestone for cars with auto-ignition. BLUETEC enables to reduce the nitrogen oxide content considerably. The target is to build a diesel engine that is as clean as a gasoline engine. Thus DaimlerChrysler owns modern diesel drives, which are economical, powerful and at the same time the cleanest in the world. (orig.)

  14. Progress in catalytic ignition fabrication and modeling : fabrication part 2.

    Science.gov (United States)

    2012-06-01

    The ignition temperature and heat generation from oxidation of methane on a platinum catalyst were : determined experimentally. A 127 micron diameter platinum coiled wire was placed crosswise in a : quartz tube of a plug flow reactor. A source meter ...

  15. Effect of health-promoting posters placed on the platforms of two train stations in Copenhagen, Denmark, on the choice between taking the stairs or the escalators

    DEFF Research Database (Denmark)

    Iversen, Mette Kathrine; Händel, M N; Nydal Jensen, Eva

    2007-01-01

    OBJECTIVE: The purpose of this study was to determine whether posters placed on the platforms of two train stations in Copenhagen, promoting use of the stairs, would encourage people to use the stairs rather than the adjacent escalator. An additional purpose was to see if the effect of the interv......OBJECTIVE: The purpose of this study was to determine whether posters placed on the platforms of two train stations in Copenhagen, promoting use of the stairs, would encourage people to use the stairs rather than the adjacent escalator. An additional purpose was to see if the effect...... of the intervention was maintained for a week after the poster was removed. MEASUREMENTS: The number of people using stairs and escalators at Copenhagen Central Station and Østerport Train Station in Copenhagen was recorded before and during posters promoting stair use were placed on the platforms, and a week after...... the posters were removed. Two years after the posters were removed, data were collected for 1 week at Østerport Train Station (long-term post-intervention). RESULTS: At Copenhagen Central Station, the overall stair use increased from 12% before the intervention to 16% (P

  16. Acoustic Igniter, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — An acoustic igniter eliminates the need to use electrical energy to drive spark systems to initiate combustion in liquid-propellant rockets. It does not involve the...

  17. Spatial determination of magnetic avalanche ignition points

    International Nuclear Information System (INIS)

    Jaafar, Reem; McHugh, S.; Suzuki, Yoko; Sarachik, M.P.; Myasoedov, Y.; Zeldov, E.; Shtrikman, H.; Bagai, R.; Christou, G.

    2008-01-01

    Using time-resolved measurements of local magnetization in the molecular magnet Mn 12 -ac, we report studies of magnetic avalanches (fast magnetization reversals) with non-planar propagating fronts, where the curved nature of the magnetic fronts is reflected in the time-of-arrival at micro-Hall sensors placed at the surface of the sample. Assuming that the avalanche interface is a spherical bubble that grows with a radius proportional to time, we are able to locate the approximate ignition point of each avalanche in a two-dimensional cross-section of the crystal. We find that although in most samples the avalanches ignite at the long ends, as found in earlier studies, there are crystals in which ignition points are distributed throughout an entire weak region near the center, with a few avalanches still originating at the ends

  18. Spatial determination of magnetic avalanche ignition points

    Energy Technology Data Exchange (ETDEWEB)

    Jaafar, Reem; McHugh, S.; Suzuki, Yoko [Physics Department, City College of the City University of New York, New York, NY 10031 (United States); Sarachik, M.P. [Physics Department, City College of the City University of New York, New York, NY 10031 (United States)], E-mail: sarachik@sci.ccny.cuny.edu; Myasoedov, Y.; Zeldov, E.; Shtrikman, H. [Department Condensed Matter Physics, Weizmann Institute of Science, Rehovot 76100 (Israel); Bagai, R.; Christou, G. [Department of Chemistry, University of Florida, Gainesville, FL 32611 (United States)

    2008-03-15

    Using time-resolved measurements of local magnetization in the molecular magnet Mn{sub 12}-ac, we report studies of magnetic avalanches (fast magnetization reversals) with non-planar propagating fronts, where the curved nature of the magnetic fronts is reflected in the time-of-arrival at micro-Hall sensors placed at the surface of the sample. Assuming that the avalanche interface is a spherical bubble that grows with a radius proportional to time, we are able to locate the approximate ignition point of each avalanche in a two-dimensional cross-section of the crystal. We find that although in most samples the avalanches ignite at the long ends, as found in earlier studies, there are crystals in which ignition points are distributed throughout an entire weak region near the center, with a few avalanches still originating at the ends.

  19. Progress of impact ignition

    International Nuclear Information System (INIS)

    Murakami, M.; Nagatomo, H.; Johzaki, T.

    2010-11-01

    In impact ignition scheme, a portion of the fuel (the impactor) is accelerated to a super-high velocity, compressed by convergence, and collided with a precompressed main fuel. This collision generates shock waves in both the impactor and the main fuel. Since the density of the impactor is generally much lower than that of the main fuel, the pressure balance ensures that the shock-heated temperature of the impactor is significantly higher than that of the main fuel. Hence, the impactor can reach ignition temperature and thus become an igniter. Here we report major new results on recent impact ignition research: (1) A maximum velocity ∼ 1000 km/s has been achieved under the operation of NIKE KrF laser at Naval Research Laboratory (laser wavelength=0.25μm) in the use of a planar target made of plastic and (2) We have performed two-dimensional simulation for burn and ignition to show the feasibility of the impact ignition. (author)

  20. Ignition tuning for the National Ignition Campaign

    OpenAIRE

    Landen O.; Edwards J.; Haan S.W.; Lindl J.D.; Boehly T.R.; Bradley D.K.; Callahan D.A.; Celliers P.M.; Dewald E.L.; Dixit S.; Doeppner T.; Eggert J.; Farley D.; Frenje J.A.; Glenn S.

    2013-01-01

    The overall goal of the indirect-drive inertial confinement fusion [1] tuning campaigns [2] is to maximize the probability of ignition by experimentally correcting for likely residual uncertainties in the implosion and hohlraum physics [3] used in our radiation-hydrodynamic computational models, and by checking for and resolving unexpected shot-to-shot variability in performance [4]. This has been started successfully using a variety of surrogate capsules that set key laser, hohlraum and caps...

  1. The volume ignition for ICF ignition target

    International Nuclear Information System (INIS)

    Li, Y. S.; He, X. T.; Yu, M.

    1997-01-01

    Compared with central model, volume ignition has no hot spot, avoids the mixing at the hot-cold interface, the α-particle escaping, and the high convergence, greatly reduces the sharp demanding for uniformity. In laser indirect driving, from theoretical estimation and computational simulation, we have proved that using a tamper with good heat resistance, the DT fuel can be ignited in LTE at ∼3 KeV and then evolves to the non-LTE ignition at >5 KeV. In this case, 1 MJ radiation energy in the hohlraum could cause near 10 MJ output for a pellet with 0.2 mg DT fuel. We have compared results with and without α-particle transport, it shows that in the condition of ρR>0.5 g/cm 2 of DT fuel, both have the same results. For the system with ρR≅0.5 g/cm 2 we can use α-particle local deposition scheme. The non-uniformly doped tamper with density ρ≅1-5 g/cc can reduce mixing due to the small convergence ratio. The input energy is deposited in DT and tamper during the implosion, we try to reduce the tamper energy by changing the ratio of CH and doped Au and the thickness of the tamper

  2. Progress towards ignition on the National Ignition Facility

    Energy Technology Data Exchange (ETDEWEB)

    Edwards, M. J.; Patel, P. K.; Lindl, J. D.; Atherton, L. J.; Glenzer, S. H.; Haan, S. W.; Landen, O. L.; Moses, E. I.; Springer, P. T.; Benedetti, R.; Bernstein, L.; Bleuel, D. L.; Bradley, D. K.; Caggiano, J. A.; Callahan, D. A.; Celliers, P. M.; Cerjan, C. J.; Clark, D. S.; Collins, G. W.; Dewald, E. L. [Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94550 (United States); and others

    2013-07-15

    The National Ignition Facility (NIF) at Lawrence Livermore National Laboratory includes a precision laser system now capable of delivering 1.8 MJ at 500 TW of 0.35-μm light to a target. NIF has been operational since March 2009. A variety of experiments have been completed in support of NIF's mission areas: national security, fundamental science, and inertial fusion energy. NIF capabilities and infrastructure are in place to support its missions with nearly 60 X-ray, optical, and nuclear diagnostic systems. A primary goal of the National Ignition Campaign (NIC) on the NIF was to implode a low-Z capsule filled with ∼0.2 mg of deuterium-tritium (DT) fuel via laser indirect-drive inertial confinement fusion and demonstrate fusion ignition and propagating thermonuclear burn with a net energy gain of ∼5–10 (fusion yield/input laser energy). This requires assembling the DT fuel into a dense shell of ∼1000 g/cm{sup 3} with an areal density (ρR) of ∼1.5 g/cm{sup 2}, surrounding a lower density hot spot with a temperature of ∼10 keV and a ρR ∼0.3 g/cm{sup 2}, or approximately an α-particle range. Achieving these conditions demand precise control of laser and target parameters to allow a low adiabat, high convergence implosion with low ablator fuel mix. We have demonstrated implosion and compressed fuel conditions at ∼80–90% for most point design values independently, but not at the same time. The nuclear yield is a factor of ∼3–10× below the simulated values and a similar factor below the alpha dominated regime. This paper will discuss the experimental trends, the possible causes of the degraded performance (the off-set from the simulations), and the plan to understand and resolve the underlying physics issues.

  3. Probability of ignition - a better approach than ignition margin

    International Nuclear Information System (INIS)

    Ho, S.K.; Perkins, L.J.

    1989-01-01

    The use of a figure of merit - the probability of ignition - is proposed for the characterization of the ignition performance of projected ignition tokamaks. Monte Carlo and analytic models have been developed to compute the uncertainty distribution function for ignition of a given tokamak design, in terms of the uncertainties inherent in the tokamak physics database. A sample analysis with this method indicates that the risks of not achieving ignition may be unacceptably high unless the accepted margins for ignition are increased. (author). Letter-to-the-editor. 12 refs, 2 figs, 2 tabs

  4. NS [Nuclear Safety] update. Current safety and security activities and developments taking place in the Department of Nuclear Safety and Security, Issue no. 6, March 2008

    International Nuclear Information System (INIS)

    2008-03-01

    The current issue presents information about the following activities: 1) International Conference on Illicit Nuclear Trafficking which took place in November 2007 in Edinburgh. The principal aim of the conference was to examine the threat and context of illicit nuclear trafficking of radioactive material, specifically, what is being done to combat such trafficking and where more needs to be done. The conference was also to consider how the obligations and commitments of the legally binding and non-binding international instruments could be and are being implemented by various States. 2) INSAG Message on Nuclear Safety Infrastructure in which the INSAG Chairman Richard Meserve addressed nuclear safety in the current context and various issues that warrant special attention. 3) approved for publication the Safety Requirements publication on Safety of Nuclear Fuel Cycle Facilities. 4) The Asian Nuclear Safety Network (ANSN)

  5. NS [Nuclear Safety] update. Current safety and security activities and developments taking place in the Department of Nuclear Safety and Security, Issue no. 8, September 2008

    International Nuclear Information System (INIS)

    2008-09-01

    The current issue presents information about the following activities: 1) International Workshops on Denial of Shipments raise awareness of suppliers, recipients, regulators, carriers/consignors and international organizations of the problems relating to denials of radioactive shipments to determine effective measures to prevent or reduce the instances of shipment denials and delays. 2) Communication and knowledge Management in the Department of Nuclear Safety and Security (NS). 3) Nuclear Security at the Beijing Olympics - an excellent example of the IAEA's work in protecting large scale public events. 4) The Incident and Emergency Centre's Participation in the ConvEx 3 Exercise, 9-10 July 2008, which took place at the Laguna Verde nuclear power plant in Mexico. During the 43 hour long exercise, the Incident and Emergency Centre (IEC) was fully activated. Staff members participating in the exercise represented different departments within the IAEA and the diversity of their knowledge and experience ensured an effective response

  6. NS [Nuclear Safety] update. Current safety and security activities and developments taking place in the Department of Nuclear Safety and Security. Issue no. 2, January 2007

    International Nuclear Information System (INIS)

    2006-08-01

    This newsletter reports on the training of cardiologists in radiation protection, IAEA's safety review services and the operational safety assessment review team (OSART), the international conference on management of spent fuel and the recent INSAG (International Nuclear Safety Group) publications. The IAEA has begun a major international initiative to train interventional cardiologists in radiation protection. Starting with the first course in May 2004, so far 6 regional and 3 national training courses have been conducted with the participation of over 400 health professionals putting the IAEA in a leading role in this area. A programme of two days' training has been developed, covering possible and observed radiation effects among patients and staff, international standards, dose management techniques, examples of good and bad practice and examples indicating prevention of possible injuries as a result of good practice in radiation protection. The training material is freely available on CD and will be placed on the Radiological Protection of Patients website at http://rpop.iaea.org/

  7. Place-focused physical activity research, human agency, and social justice in public health: taking agency seriously in studies of the built environment.

    Science.gov (United States)

    Blacksher, Erika; Lovasi, Gina S

    2012-03-01

    Built environment characteristics have been linked to health outcomes and health disparities. However, the effects of an environment on behavior may depend on human perception, interpretation, motivation, and other forms of human agency. We draw on epidemiological and ethical concepts to articulate a critique of research on the built environment and physical activity. We identify problematic assumptions and enumerate both scientific and ethical reasons to incorporate subjective perspectives and public engagement strategies into built environment research and interventions. We maintain that taking agency seriously is essential to the pursuit of health equity and the broader demands of social justice in public health, an important consideration as studies of the built environment and physical activity increasingly focus on socially disadvantaged communities. Attention to how people understand their environment and navigate competing demands can improve the scientific value of ongoing efforts to promote active living and health, while also better fulfilling our ethical obligations to the individuals and communities whose health we strive to protect. Copyright © 2011 Elsevier Ltd. All rights reserved.

  8. Leaf processing behaviour in Atta leafcutter ants: 90% of leaf cutting takes place inside the nest, and ants select pieces that require less cutting.

    Science.gov (United States)

    Garrett, Ryan W; Carlson, Katherine A; Goggans, Matthew Scott; Nesson, Michael H; Shepard, Christopher A; Schofield, Robert M S

    2016-01-01

    Leafcutter ants cut trimmings from plants, carry them to their underground nests and cut them into smaller pieces before inoculating them with a fungus that serves as a primary food source for the colony. Cutting is energetically costly, so the amount of cutting is important in understanding foraging energetics. Estimates of the cutting density, metres of cutting per square metre of leaf, were made from samples of transported leaf cuttings and of fungal substrate from field colonies of Atta cephalotes and Atta colombica. To investigate cutting inside the nest, we made leaf-processing observations of our laboratory colony, A. cephalotes. We did not observe the commonly reported reduction of the leaf fragments into a pulp, which would greatly increase the energy cost of processing. Video clips of processing behaviours, including behaviours that have not previously been described, are linked. An estimated 2.9 (±0.3) km of cutting with mandibles was required to reduce a square metre of leaf to fungal substrate. Only about 12% (±1%) of this cutting took place outside of the nest. The cutting density and energy cost is lower for leaf material with higher ratios of perimeter to area, so we tested for, and found that the laboratory ants had a preference for leaves that were pre-cut into smaller pieces. Estimates suggest that the energy required to transport and cut up the leaf material is comparable to the metabolic energy available from the fungus grown on the leaves, and so conservation of energy is likely to be a particularly strong selective pressure for leafcutter ants.

  9. Hypoxia and inactivity related physiological changes precede or take place in absence of significant rearrangements in bacterial community structure: The PlanHab randomized trial pilot study.

    Directory of Open Access Journals (Sweden)

    Robert Šket

    Full Text Available We explored the assembly of intestinal microbiota in healthy male participants during the randomized crossover design of run-in (5 day and experimental phases (21-day normoxic bed rest (NBR, hypoxic bed rest (HBR and hypoxic ambulation (HAmb in a strictly controlled laboratory environment, with balanced fluid and dietary intakes, controlled circadian rhythm, microbial ambiental burden and 24/7 medical surveillance. The fraction of inspired O2 (FiO2 and partial pressure of inspired O2 (PiO2 were 0.209 and 133.1 ± 0.3 mmHg for NBR and 0.141 ± 0.004 and 90.0 ± 0.4 mmHg for both hypoxic variants (HBR and HAmb; ~4000 m simulated altitude, respectively. A number of parameters linked to intestinal environment such as defecation frequency, intestinal electrical conductivity (IEC, sterol and polyphenol content and diversity, indole, aromaticity and spectral characteristics of dissolved organic matter (DOM were measured (64 variables. The structure and diversity of bacterial microbial community was assessed using 16S rRNA amplicon sequencing. Inactivity negatively affected frequency of defecation and in combination with hypoxia increased IEC (p < 0.05. In contrast, sterol and polyphenol diversity and content, various characteristics of DOM and aromatic compounds, the structure and diversity of bacterial microbial community were not significantly affected over time. A new in-house PlanHab database was established to integrate all measured variables on host physiology, diet, experiment, immune and metabolic markers (n = 231. The observed progressive decrease in defecation frequency and concomitant increase in IEC suggested that the transition from healthy physiological state towards the developed symptoms of low magnitude obesity-related syndromes was dose dependent on the extent of time spent in inactivity and preceded or took place in absence of significant rearrangements in bacterial microbial community. Species B. thetaiotamicron, B. fragilis, B

  10. Proton Fast Ignition

    International Nuclear Information System (INIS)

    Key, M H; Freeman, R R; Hatchett, S P; MacKinnon, A J; Patel, P K; Snavely, R A; Stephens, R B

    2006-04-01

    Fast ignition (FI) by a laser generated ballistically focused proton beam is a more recently proposed alternative to the original concept of FI by a laser generated beam of relativistic electrons. It has potential advantages in less complex energy transport into dense plasma. Recent successful target heating experiments motivate further investigation of the feasibility of proton fast ignition. The concept, the physics and characteristics of the proton beams, the recent experimental work on focusing of the beams and heating of solid targets and the overall prospects for proton FI are discussed

  11. Magnetically Assisted Fast Ignition

    OpenAIRE

    Wang, W.-M.; Gibbon, P.; Sheng, Z.-M.; Li, Y.-T.

    2015-01-01

    Fast ignition (FI) is investigated via integrated particle-in-cell simulation including both generation andtransport of fast electrons, where petawatt ignition lasers of 2 ps and compressed targets of a peak density of300 g cm−3 and areal density of 0.49 g cm−2 at the core are taken. When a 20 MG static magnetic field isimposed across a conventional cone-free target, the energy coupling from the laser to the core is enhancedby sevenfold and reaches 14%. This value even exceeds that obtained u...

  12. Designated Places

    Data.gov (United States)

    California Natural Resource Agency — Census 2000 Place Names provides a seamless statewide GIS layer of places, including census designated places (CDP), consolidated cities, and incorporated places,...

  13. Visualizing ignition and combustion of methanol mixtures in a diesel engine; Methanol funmu no glow chakka to nensho no kashika

    Energy Technology Data Exchange (ETDEWEB)

    Inomoto, Y; Harada, T; Kusaka, J; Daisho, Y; Kihara, R; Saito, T [Waseda University, Tokyo (Japan)

    1997-10-01

    A glow-assisted ignition system tends to suffer from poor ignitability and slow flame propagation at low load in a direct-injection diesel engine fueled with methanol. To investigate the ignition process and improve such disadvantages, methanol sprays, their ignition and flames were visualized at high pressures and temperatures using a modified two-stroke engine. The results show that parameters influencing ignition, the location of a glow-plug, swirl level, pressure and temperature are important. In addition, a full kinetics calculation was conducted to predict the delay of methanol mixture ignition by taking into account 39 chemical species and 157 elementary reactions. 3 refs., 9 figs.

  14. Ignition experiment - alternatives

    International Nuclear Information System (INIS)

    Knobloch, A.F.

    1979-10-01

    This report comprises three short papers on cost estimates, integral burn time and alternative versions of Tokamak ignition experiments. These papers were discussed at the ZEPHYR workshop with participants from IPP Garching, MIT Cambridge and PPPL Princeton (Garching July 30 - August 2 1979) (Chapters A, B, C). It is shown, that starting from a practical parameter independent minimum integral burn time of Tokamak ignition experiments (some 10 3 s) by adding a shield for protection of the magnet insulation (permitted neutron dose 10 9 rad) an integral burn time of some 10 4 s can be achieved for only about 30% more outlay. For a substantially longer integral burn time the outlay approaches rather quickly that for a Tokamak reactor. Some examples for alternatives to ZEPHYR are being given, including some with low or no compression. In a further chapter D some early results of evaluating an ignition experiment on the basis of the energy confinement scaling put forward by Coppi and Mazzucato are presented. As opposed to the case of the Alcator scaling used in chapters A through C the minimum integral burn time of Tokamak ignition experiments here depends on the plasma current. Provided neutral injectors up to about 160 keV are available compression boosting is not required with this scaling. The results presented have been obtained neglecting the effects of the toroidal field ripple. (orig.) 891 HT/orig. 892 RKD [de

  15. Equilibrium ignition for ICF capsules

    International Nuclear Information System (INIS)

    Lackner, K.S.; Colgate, S.A.; Johnson, N.L.; Kirkpatrick, R.C.; Menikoff, R.; Petschek, A.G.

    1993-01-01

    There are two fundamentally different approaches to igniting DT fuel in an ICF capsule which can be described as equilibrium and hot spot ignition. In both cases, a capsule which can be thought of as a pusher containing the DT fuel is imploded until the fuel reaches ignition conditions. In comparing high-gain ICF targets using cryogenic DT for a pusher with equilibrium ignition targets using high-Z pushers which contain the radiation. The authors point to the intrinsic advantages of the latter. Equilibrium or volume ignition sacrifices high gain for lower losses, lower ignition temperature, lower implosion velocity and lower sensitivity of the more robust capsule to small fluctuations and asymmetries in the drive system. The reduction in gain is about a factor of 2.5, which is small enough to make the more robust equilibrium ignition an attractive alternative

  16. Major growth in coke production takes place

    International Nuclear Information System (INIS)

    Swain, E.J.

    1991-01-01

    U.S. petroleum coke production has increased 64% during the 10-year period from 1980 to 1990. This dramatic rise makes it timely to discuss the history and future of U.S. coking capacity, production, and processing. The article covers the properties and uses of the various grades of petroleum coke, as well as pricing and market trends

  17. Shock Tube Ignition Delay Data Affected by Localized Ignition Phenomena

    KAUST Repository

    Javed, Tamour

    2016-12-29

    Shock tubes have conventionally been used for measuring high-temperature ignition delay times ~ O(1 ms). In the last decade or so, the operating regime of shock tubes has been extended to lower temperatures by accessing longer observation times. Such measurements may potentially be affected by some non-ideal phenomena. The purpose of this work is to measure long ignition delay times for fuels exhibiting negative temperature coefficient (NTC) and to assess the impact of shock tube non-idealities on ignition delay data. Ignition delay times of n-heptane and n-hexane were measured over the temperature range of 650 – 1250 K and pressures near 1.5 atm. Driver gas tailoring and long length of shock tube driver section were utilized to measure ignition delay times as long as 32 ms. Measured ignition delay times agree with chemical kinetic models at high (> 1100 K) and low (< 700 K) temperatures. In the intermediate temperature range (700 – 1100 K), however, significant discrepancies are observed between the measurements and homogeneous ignition delay simulations. It is postulated, based on experimental observations, that localized ignition kernels could affect the ignition delay times at the intermediate temperatures, which lead to compression (and heating) of the bulk gas and result in expediting the overall ignition event. The postulate is validated through simple representative computational fluid dynamic simulations of post-shock gas mixtures which exhibit ignition advancement via a hot spot. The results of the current work show that ignition delay times measured by shock tubes may be affected by non-ideal phenomena for certain conditions of temperature, pressure and fuel reactivity. Care must, therefore, be exercised in using such data for chemical kinetic model development and validation.

  18. Pulse heating and ignition for off-centre ignited targets

    International Nuclear Information System (INIS)

    Mahdy, A.I.; Takabe, H.; Mima, K.

    1999-01-01

    An off-centre ignition model has been used to study the ignition conditions for laser targets related to the fast ignition scheme. A 2-D hydrodynamic code has been used, including alpha particle heating. The main goal of the study is the possibility of obtaining a high gain ICF target with fast ignition. In order to determine the ignition conditions, samples with various compressed core densities having different spark density-radius product (i.e. areal density) values were selected. The study was carried out in the presence of an external heating source, with a constant heating rate. A dependence of the ignition conditions on the heating rate of the external pulse is demonstrated. For a given set of ignition conditions, our simulation showed that an 11 ps pulse with 17 kJ of injected energy into the spark area was required to achieve ignition for a compressed core with a density of 200 g/cm 3 and 0.5 g/cm 2 spark areal density. It is shown that the ignition conditions are highly dependent on the heating rate of the external pulse. (author)

  19. Ignition and fusion burn in fast ignition scheme

    International Nuclear Information System (INIS)

    Takabe, Hideaki

    1998-01-01

    The target physics of fast ignition is briefly reviewed by focusing on the ignition and fusion burn in the off-center ignition scheme. By the use of a two dimensional hydrodynamic code with an alpha heating process, the ignition condition is studied. It is shown that the ignition condition of the off-center ignition scheme coincides with that of the the central isochoric model. After the ignition, a nuclear burning wave is seen to burn the cold main fuel with a velocity of 2 - 3 x 10 8 cm/s. The spark energy required for the off-center ignition is 2 - 3 kJ or 10 - 15 kJ for the core density of 400 g/cm 3 or 200 g/cm 3 , respectively. It is demonstrated that a core gain of more than 2,000 is possible for a core energy of 100 kJ with a hot spark energy of 13 kJ. The requirement for the ignition region's heating time is also discussed by modeling a heating source in the 2-D code. (author)

  20. Ignition Delay of Combustible Materials in Normoxic Equivalent Environments

    Science.gov (United States)

    McAllister, Sara; Fernandez-Pello, Carlos; Ruff, Gary; Urban, David

    2009-01-01

    Material flammability is an important factor in determining the pressure and composition (fraction of oxygen and nitrogen) of the atmosphere in the habitable volume of exploration vehicles and habitats. The method chosen in this work to quantify the flammability of a material is by its ease of ignition. The ignition delay time was defined as the time it takes a combustible material to ignite after it has been exposed to an external heat flux. Previous work in the Forced Ignition and Spread Test (FIST) apparatus has shown that the ignition delay in the currently proposed space exploration atmosphere (approximately 58.6 kPa and32% oxygen concentration) is reduced by 27% compared to the standard atmosphere used in the Space Shuttle and Space Station. In order to determine whether there is a safer environment in terms of material flammability, a series of piloted ignition delay tests using polymethylmethacrylate (PMMA) was conducted in the FIST apparatus to extend the work over a range of possible exploration atmospheres. The exploration atmospheres considered were the normoxic equivalents, i.e. reduced pressure conditions with a constant partial pressure of oxygen. The ignition delay time was seen to decrease as the pressure was reduced along the normoxic curve. The minimum ignition delay observed in the normoxic equivalent environments was nearly 30% lower than in standard atmospheric conditions. The ignition delay in the proposed exploration atmosphere is only slightly larger than this minimum. Interms of material flammability, normoxic environments with a higher pressure relative to the proposed pressure would be desired.

  1. Central ignition scenarios for TFTR

    International Nuclear Information System (INIS)

    Zweben, S.J.; Redi, M.H.; Bateman, G.

    1986-03-01

    The possibility of obtaining ignition in TFTR by means of very centrally peaked density profiles is examined. It is shown that local central alpha heating can be made to exceed local central energy losses (''central ignition'') under global conditions for which Q greater than or equal to 1. Time dependent 1-D transport simulations show that the normal global ignition requirements are substantially relaxed for plasmas with peaked density profiles. 18 refs., 18 figs

  2. Research on cylinder processes of gasoline homogenous charge compression ignition (HCCI) engine

    Science.gov (United States)

    Cofaru, Corneliu

    2017-10-01

    This paper is designed to develop a HCCI engine starting from a spark ignition engine platform. The engine test was a single cylinder, four strokes provided with carburetor. The results of experimental research on this version were used as a baseline for the next phase of the work. After that, the engine was modified for a HCCI configuration, the carburetor was replaced by a direct fuel injection system in order to control precisely the fuel mass per cycle taking into account the measured intake air-mass. To ensure that the air - fuel mixture auto ignite, the compression ratio was increased from 9.7 to 11.5. The combustion process in HCCI regime is governed by chemical kinetics of mixture of air-fuel, rein ducted or trapped exhaust gases and fresh charge. To modify the quantities of trapped burnt gases, the exchange gas system was changed from fixed timing to variable valve timing. To analyze the processes taking place in the HCCI engine and synthesizing a control system, a model of the system which takes into account the engine configuration and operational parameters are needed. The cylinder processes were simulated on virtual model. The experimental research works were focused on determining the parameters which control the combustion timing of HCCI engine to obtain the best energetic and ecologic parameters.

  3. Laser ignition - Spark plug development and application in reciprocating engines

    Science.gov (United States)

    Pavel, Nicolaie; Bärwinkel, Mark; Heinz, Peter; Brüggemann, Dieter; Dearden, Geoff; Croitoru, Gabriela; Grigore, Oana Valeria

    2018-03-01

    solutions for positioning of the laser spark plug, i.e. placing it apart from or directly on the engine, are introduced. The path taken from the first solution proposed, to build a compact laser suitable for ignition, to the practical realization of a laser spark plug is described. Results obtained by ignition of automobile test engines, with laser devices that resemble classical spark plugs, are specifically discussed. It is emphasized that technological advances have brought this method of laser ignition close to the application and installation in automobiles powered by gasoline engines. Achievements made in the laser ignition of natural gas engines are outlined, as well as the utilization of laser ignition in other applications. Scientific and technical advances have allowed realization of laser devices with multiple (up to four) beam outputs, but many other important aspects (such as integration, thermal endurance or vibration strength) are still to be solved. Recent results of multi-beam ignition of a single-cylinder engine in a test bench set-up are encouraging and have led to increased research interest in this direction. A fundamental understanding of the processes involved in laser ignition is crucial in order to exploit the technology's full potential. Therefore, several measurement techniques, primarily optical types, used to characterize the laser ignition process are reviewed in this work.

  4. High-Gain Shock Ignition on the National Ignition Facility

    Science.gov (United States)

    Perkins, L. J.; Lafortune, K.; Bailey, D.; Lambert, M.; MacKinnon, A.; Blackfield, D.; Comley, A.; Schurtz, G.; Ribeyre, X.; Lebel, E.; Casner, A.; Craxton, R. S.; Betti, R.; McKenty, P.; Anderson, K.; Theobald, W.; Schmitt, A.; Atzeni, S.; Schiavi, A.

    2010-11-01

    Shock ignition offers the possibility for a near-term test of high-gain ICF on the NIF at less than 1MJ drive energy and with day-1 laser hardware. We will summarize the status of target performance simulations, delineate the critical issues and describe the R&D program to be performed in order to test the potential of a shock-ignited target on NIF. In shock ignition, compressed fuel is separately ignited by a late-time laser-driven shock and, because capsule implosion velocities are significantly lower than those required for conventional hotpot ignition, simulations indicate that fusion energy gains of 60 may be achievable at laser energies around 0.5MJ. Like fast ignition, shock ignition offers high gain but requires only a single laser with less demanding timing and focusing requirements. Conventional symmetry and stability constraints apply, thus a key immediate step towards attempting shock ignition on NIF is to demonstrate adequacy of low-mode uniformity and shock symmetry under polar drive

  5. Compact ignition experiments

    International Nuclear Information System (INIS)

    Angelini, A.; Coppi, B.; Nassi, M.

    1992-01-01

    This paper reports on high magnetic field experiments which can be designed to investigate D-T ignition conditions based on present-day experimental results and theoretical understanding of plasma phenomena. The key machine elements are: large plasma currents, compact dimensions, tight aspect ratios, moderate elongations and significant triangularities of the plasma column. High plasma densities, strong ohmic heating, the needed degree of energy confinement, good plasma purity and robust stability against ideal and resistive instabilities can be achieved simultaneously. The Ignitor design incorporates all these characteristics and involves magnet technology developments, started with the Alcator experiment, that use cryogenically cooled normal conductors

  6. Ignition and Inertial Confinement Fusion at The National Ignition Facility

    International Nuclear Information System (INIS)

    Moses, E.

    2009-01-01

    The National Ignition Facility (NIF), the world's largest and most powerful laser system for inertial confinement fusion (ICF) and for studying high-energy-density (HED) science, is now operational at Lawrence Livermore National Laboratory (LLNL). The NIF is now conducting experiments to commission the laser drive, the hohlraum and the capsule and to develop the infrastructure needed to begin the first ignition experiments in FY 2010. Demonstration of ignition and thermonuclear burn in the laboratory is a major NIF goal. NIF will achieve this by concentrating the energy from the 192 beams into a mm 3 -sized target and igniting a deuterium-tritium mix, liberating more energy than is required to initiate the fusion reaction. NIF's ignition program is a national effort managed via the National Ignition Campaign (NIC). The NIC has two major goals: execution of DT ignition experiments starting in FY2010 with the goal of demonstrating ignition and a reliable, repeatable ignition platform by the conclusion of the NIC at the end of FY2012. The NIC will also develop the infrastructure and the processes required to operate NIF as a national user facility. The achievement of ignition at NIF will demonstrate the scientific feasibility of ICF and focus worldwide attention on laser fusion as a viable energy option. A laser fusion-based energy concept that builds on NIF, known as LIFE (Laser Inertial Fusion Energy), is currently under development. LIFE is inherently safe and can provide a global carbon-free energy generation solution in the 21st century. This paper describes recent progress on NIF, NIC, and the LIFE concept.

  7. Investigation of possibilities of ignition of target plasma in conditions of inertial thermonuclear synthesis

    International Nuclear Information System (INIS)

    Andreev, A.A.; Gus'kov, S.Yu.; Rozanov, V.B.; Il'in, D.V.; Levkovskij, A.A.; Sherman, V.E.

    2001-01-01

    On the basis of mathematical simulation of thermonuclear burning of DT-plasma of laser targets one calculated G factors of thermonuclear intensification for a space and a spark ignitions at various parameters of target plasma and igniters (both isobaric and isochoric). One calculated the critical parameters of igniters upon reaching of which the efficient thermonuclear burst with G ∼ 100 took place. It is shown that further increase of temperature and of dimensions of igniters does not practically affect the efficiency of DT-fuel burnup and independently of the way of ignition G value may be estimated using a simple asymptotic expression. At the same time the values of the critical parameters of igniters depend essentially on the way of ignition and on target parameters. One studied in detail the spark ignition with isochoric igniter. Thermal energy generated at absorption of supershort additional laser pulse is shown to be the key critical parameter for the optimal isochoric igniters. Critical parameters of this energy are calculated [ru

  8. Tokamak and RFP ignition requirements

    International Nuclear Information System (INIS)

    Werley, K.A.

    1991-01-01

    A plasma model is applied to calculate numerically transport- confinement (nτ E ) requirements and steady-state operation tokamak. The CIT tokamak and RFP ignition conditions are examined. Physics differences between RFP and tokamaks, and their consequences for a DT ignition machine, are discussed. The ignition RFP, compared to a tokamak, has many physics advantages, including ohmic heating to ignition (no need for auxiliary heating systems), higher beta, low ignition current, less sensitivity of ignition requirements to impurity effects, no hard disruptions (associated with beta or density limits), and successful operation with high radiation fractions (f RAD ∼ 0.95). These physics advantages, coupled with important engineering advantages associated with lower external magnetic fields, larger aspect ratios, and smaller plasma cross sections translate into significant cost reductions for both ignition and power reactor. The primary drawback of the RFP is the uncertainty that the present confinement scaling will extrapolate to reactor regimes. The 4-MA ZTH was expected to extend the nτ E transport scaling data three order of magnitude above ZT-40M results, and if the present scaling held, to achieve a DT-equivalent scientific energy breakeven, Q=1. A basecase RFP ignition point is identified with a plasma current of 8.1 MA and no auxiliary heating. 16 refs., 4 figs., 1 tab

  9. Plasma engineering assessments of compact ignition experiments

    International Nuclear Information System (INIS)

    Houlberg, W.A.

    1985-01-01

    Confinement, startup sequences, and fast-alpha particle effects are assessed for a class of compact tokamak ignition experiments having high toroidal magnetic fields (8 to 12 T) and high toroidal currents (7 to 10 MA). The uncertainties in confinement scaling are spanned through examples of performance with an optimistic model based on ohmically heated plasmas and a pessimistic model that includes confinement degradation by both auxiliary and alpha heating. The roles of neoclassical resistivity enhancement and sawtooth behavior are also evaluated. Copper toroidal field coils place restrictions on pulse lengths due to resistive heating, so a simultaneous rampup of the toroidal field and plasma current is proposed as a means of compressing the startup phase and lengthening the burn phase. If the ignition window is small, fast-alpha particle physics is restricted to the high-density regime where a short slowing-down time leads to low fast-particle density and pressure contributions. Under more optimistic confinement, a larger ignition margin broadens the range of alpha particle physics that can be addressed. These issues are illustrated through examples of transport simulations for a set of machine parameters called BRAND-X, which typify the designs under study

  10. Plasma engineering assessments of compact ignition experiments

    International Nuclear Information System (INIS)

    Houlberg, W.A.

    1986-01-01

    Confinement, startup sequences, and fast-alpha particle effects are assessed for a class of compact tokamak ignition experiments having high toroidal magnetic fields (8-12 T) and high toroidal currents (7-10 MA). The uncertainties in confinement scaling are spanned through examples of performance with an optimistic model based on ohmically heated plasmas and a pessimistic model that includes confinement degradation by both auxiliary and alpha heating. The roles of neoclassical resistivity enhancement and sawtooth behavior are also evaluated. Copper toroidal field coils place restrictions on pulse lengths due to resistive heating, so a simultaneous rampup of the toroidal field and plasma current is proposed as a means of compressing the startup phase and lengthening the burn phase. If the ignition window is small, fast-alpha particle physics is restricted to the high-density regime where a short slowing-down time leads to low fast-particle density and pressure contributions. Under more optimistic confinement, a larger ignition margin broadens the range of alpha particle physics that can be addressed. These issues are illustrated through examples of transport simulations for a set of machine parameters called BRAND-X, which typify the designs under study

  11. Influence of radiative processes on the ignition of deuterium–tritium plasma containing inactive impurities

    Energy Technology Data Exchange (ETDEWEB)

    Gus’kov, S. Yu., E-mail: guskov@sci.lebedev.ru [Russian Academy of Sciences, Lebedev Physical Institute (Russian Federation); Sherman, V. E. [Peter the Great St. Petersburg Polytechnic University (Russian Federation)

    2016-08-15

    The degree of influence of radiative processes on the ignition of deuterium–tritium (DT) plasma has been theoretically studied as dependent on the content of inactive impurities in plasma. The analytic criterion of plasma ignition in inertial confinement fusion (ICF) targets is modified taking into account the absorption of intrinsic radiation from plasma in the ignition region. The influence of radiative processes on the DT plasma ignition has been analytically and numerically studied for plasma that contains a significant fraction of inactive impurities either as a result of DT fuel mixing with ICF target ablator material or as a result of using light metal DT-hydrides as solid noncryogenic fuel. It has been shown that the effect of the absorption of intrinsic radiation leads to lower impurity-induced increase in the ignition energy as compared to that calculated in the approximation of optically transparent ignition region.

  12. Target design for shock ignition

    International Nuclear Information System (INIS)

    Schurtz, G; Ribeyre, X; Lafon, M

    2010-01-01

    The conventional approach of laser driven inertial fusion involves the implosion of cryogenic shells of deuterium-tritium ice. At sufficiently high implosion velocities, the fuel ignites by itself from a central hot spot. In order to reduce the risks of hydrodynamic instabilities inherent to large implosion velocities, it was proposed to compress the fuel at low velocity, and ignite the compressed fuel by means of a convergent shock wave driven by an intense spike at the end of the laser pulse. This scheme, known as shock ignition, reduces the risks of shell break-up during the acceleration phase, but it may be impeded by a low coupling efficiency of the laser pulse with plasma at high intensities. This work provides a relationship between the implosion velocity and the laser intensity required to ignite the target by a shock. The operating domain of shock ignition at different energies is described.

  13. The Ignition Target for the National Ignition Facility

    International Nuclear Information System (INIS)

    Atherton, L J; Moses, E I; Carlisle, K; Kilkenny, J

    2007-01-01

    The National Ignition Facility (NIF) is a 192 beam Nd-glass laser facility presently under construction at Lawrence Livermore National Laboratory (LLNL) for performing inertial confinement fusion (ICF) and experiments studying high energy density (HED) science. When completed in 2009, NIF will be able to produce 1.8 MJ, 500 TW of ultraviolet light for target experiments that will create conditions of extreme temperatures (>10 8 K), pressures (10-GBar) and matter densities (> 100 g/cm 3 ). A detailed program called the National Ignition Campaign (NIC) has been developed to enable ignition experiments in 2010, with the goal of producing fusion ignition and burn of a deuterium-tritium (DT) fuel mixture in millimeter-scale target capsules. The first of the target experiments leading up to these ignition shots will begin in 2008. Targets for the National Ignition Campaign are both complex and precise, and are extraordinarily demanding in materials fabrication, machining, assembly, cryogenics and characterization. An overview of the campaign for ignition will be presented, along with technologies for target fabrication, assembly and metrology and advances in growth and x-ray imaging of DT ice layers. The sum of these efforts represents a quantum leap in target precision, characterization, manufacturing rate and flexibility over current state-of-the-art

  14. Piezoelectrically Initiated Pyrotechnic Igniter

    Science.gov (United States)

    Quince, Asia; Dutton, Maureen; Hicks, Robert; Burnham, Karen

    2013-01-01

    This innovation consists of a pyrotechnic initiator and piezoelectric initiation system. The device will be capable of being initiated mechanically; resisting initiation by EMF, RF, and EMI (electromagnetic field, radio frequency, and electromagnetic interference, respectively); and initiating in water environments and space environments. Current devices of this nature are initiated by the mechanical action of a firing pin against a primer. Primers historically are prone to failure. These failures are commonly known as misfires or hang-fires. In many cases, the primer shows the dent where the firing pin struck the primer, but the primer failed to fire. In devices such as "T" handles, which are commonly used to initiate the blowout of canopies, loss of function of the device may result in loss of crew. In devices such as flares or smoke generators, failure can result in failure to spot a downed pilot. The piezoelectrically initiated ignition system consists of a pyrotechnic device that plugs into a mechanical system (activator), which on activation, generates a high-voltage spark. The activator, when released, will strike a stack of electrically linked piezo crystals, generating a high-voltage, low-amperage current that is then conducted to the pyro-initiator. Within the initiator, an electrode releases a spark that passes through a pyrotechnic first-fire mixture, causing it to combust. The combustion of the first-fire initiates a primary pyrotechnic or explosive powder. If used in a "T" handle, the primary would ramp the speed of burn up to the speed of sound, generating a shock wave that would cause a high explosive to go "high order." In a flare or smoke generator, the secondary would produce the heat necessary to ignite the pyrotechnic mixture. The piezo activator subsystem is redundant in that a second stack of crystals would be struck at the same time with the same activation force, doubling the probability of a first strike spark generation. If the first

  15. The National Ignition Facility (NIF): A path to fusion energy

    International Nuclear Information System (INIS)

    Moses, Edward I.

    2008-01-01

    Fusion energy has long been considered a promising, clean, nearly inexhaustible source of energy. Power production by fusion micro-explosions of inertial confinement fusion (ICF) targets has been a long-term research goal since the invention of the first laser in 1960. The National Ignition Facility (NIF) is poised to take the next important step in the journey by beginning experiments researching ICF ignition. Ignition on NIF will be the culmination of over 30 years of ICF research on high-powered laser systems such as the Nova laser at Lawrence Livermore National Laboratory (LLNL) and the OMEGA laser at the University of Rochester, as well as smaller systems around the world. NIF is a 192-beam Nd-glass laser facility at LLNL that is more than 90% complete. The first cluster of 48 beams is operational in the laser bay, the second cluster is now being commissioned, and the beam path to the target chamber is being installed. The Project will be completed in 2009, and ignition experiments will start in 2010. When completed, NIF will produce up to 1.8 MJ of 0.35-μm light in highly shaped pulses required for ignition. It will have beam stability and control to higher precision than any other laser fusion facility. Experiments using one of the beams of NIF have demonstrated that NIF can meet its beam performance goals. The National Ignition Campaign (NIC) has been established to manage the ignition effort on NIF. NIC has all of the research and development required to execute the ignition plan and to develop NIF into a fully operational facility. NIF will explore the ignition space, including direct drive, 2ω ignition, and fast ignition, to optimize target efficiency for developing fusion as an energy source. In addition to efficient target performance, fusion energy requires significant advances in high-repetition-rate lasers and fusion reactor technology. The Mercury laser at LLNL is a high-repetition-rate Nd-glass laser for fusion energy driver development. Mercury

  16. The National Ignition Facility

    International Nuclear Information System (INIS)

    Hogan, W.J.; Moses, E.; Warner, B.; Sorem, M.; Soures, J.M.

    2001-01-01

    The National Ignition Facility (NIF) is the largest construction project ever undertaken at Lawrence Livermore National Laboratory (LLNL). NIF consists of 192 forty-centimeter-square laser beams and a 10-m-diameter target chamber. NIF is being designed and built by an LLNL-led team from Los Alamos National Laboratory, Sandia National Laboratories, the University of Rochester, and LLNL. Physical construction began in 1997. The Laser and Target Area Building and the Optics Assembly Building were the first major construction activities, and despite several unforeseen obstacles, the buildings are now 92% complete and have been done on time and within cost. Prototype component development and testing has proceeded in parallel. Optics vendors have installed full-scale production lines and have done prototype production runs. The assembly and integration of the beampath infrastructure has been reconsidered and a new approach has been developed. This paper will discuss the status of the NIF project and the plans for completion. (author)

  17. The Compact Ignition Tokamak

    International Nuclear Information System (INIS)

    Schmidt, J.

    1987-01-01

    The author discusses his lab's plan for completing the Compact Ignition Tokamak (CIT) conceptual design during calendar year 1987. Around July 1 they froze the subsystem envelopes on the device to continue with the conceptual design. They did this by formalizing a general requirements document. They have been developing the management plan and submitted a version to the DOE July 10. He describes a group of management activities. They released the vacuum vessel Request For Proposals (RFP) on August 5. An RFP to do a major part of the system engineering on the device is being developed. They intend to assemble the device outside of the test cell, then move it into the the test cell, install it there, and bring to the test cell many of the auxiliary facilities from TFTR, for example, power supplies

  18. Reversed field pinch ignition requirements

    International Nuclear Information System (INIS)

    Werley, K.A.

    1991-01-01

    Plasma models are described and used to calculated numerically the transport confinement (nτ E ) requirements and steady state operation points for both the reversed field pinch (RFP) and the tokamak. The models are used to examine the CIT tokamak ignition conditions and the RFP experimental and ignition conditions. Physics differences between RFPs and tokamaks and their consequences for a D-T ignition machine are discussed. Compared with a tokamak, the ignition RFP has many physics advantages, including Ohmic heating to ignition (no need for auxiliary heating systems), higher beta, lower ignition current, less sensitivity of ignition requirements to impurity effects, no hard disruptions (associated with beta or density limits) and successful operation with high radiation fractions (f RAD ∼ 0.95). These physics advantages, coupled with important engineering advantages associated with lower external magnetic field, larger aspect ratios and smaller plasma cross-sections, translate to significant cost reductions for both ignition and reactor applications. The primary drawback of the RFP is the uncertainty that the present scaling will extrapolate to reactor regimes. Devices that are under construction should go a long way toward resolving this scaling uncertainty. The 4 MA ZTH is expected to extend the nτ E transport scaling data by three orders of magnitude above the results of ZT-40M, and, if the present scaling holds, ZTH is expected to achieve a D-T equivalent scientific energy breakeven, Q = 1. A base case RFP ignition point is identified with a plasma current of 8.1 MA and no auxiliary heating. (author). 19 refs, 11 figs, 3 tabs

  19. Connecting people to place

    NARCIS (Netherlands)

    Horlings, L.G.

    2016-01-01

    The article describes a process of preparing a research design on place-shaping, as outcome of a process of co-design between academic actors and non-academic actors in Brazil, South Africa and The Netherlands, taking place in the context of the project TRANSPLACE. The joint research design

  20. Shock Tube Ignition Delay Data Affected by Localized Ignition Phenomena

    KAUST Repository

    Javed, Tamour; Badra, J.; Jaasim, Mohammed; Es-sebbar, Et-touhami; Labastida, M.F.; Chung, Suk-Ho; Im, Hong G.; Farooq, Aamir

    2016-01-01

    Shock tubes have conventionally been used for measuring high-temperature ignition delay times ~ O(1 ms). In the last decade or so, the operating regime of shock tubes has been extended to lower temperatures by accessing longer observation times

  1. Whist code calculations of ignition margin in an ignition tokamak

    International Nuclear Information System (INIS)

    Sheffield, J.

    1985-01-01

    A simple global model was developed to determine the ignition margin of tokamaks including electron and ion conduction losses. A comparison of this model with results from a 1 1/2 dimensional Whist code is made

  2. Children's Places

    DEFF Research Database (Denmark)

    Using a cross-cultural approach the book investigates children's places in different societies. "Children's Places" examines the ways in which children and adults, from their different vantage-points in society, negotiate proper places of children in both social and spatial terms. It looks at some...

  3. Development and testing of hydrogen ignition devices

    International Nuclear Information System (INIS)

    Renfro, D.; Smith, L.; Thompson, L.; Clever, R.

    1982-01-01

    Controlled ignition systems for the mitigation of hydrogen produced during degraded core accidents have been installed recently in several light water reactor (LWR) containments. This paper relates the background of the thermal igniter approach and its application to LWR controlled ignition systems. The process used by the Tennessee Valley Authority (TVA) to select a hydrogen mitigation system in general and an igniter type in particular is described. Descriptions of both the Interim Distributed Ignition System and the Permanent Hydrogen Mitigation System installed by TVA are included as examples. Testing of igniter durability at TVA's Singleton Materials Engineering Laboratory and of igniter performance at Atomic Energy of Canada's Whiteshell Nuclear Research Establishment is presented

  4. Women take the island: nation, profession, place Women take the island: nation, profession, place

    Directory of Open Access Journals (Sweden)

    Ruth Morse

    2008-04-01

    Full Text Available The Tempest has been one of Shakespeare’s most adapted plays. Its stage history is concomitantly a history of the British theatre, from regularized comedy to semi-opera to pantomime to opera. It has had other lives, too, from its position in romantic ideas of Shakespeare’s biography and his so-called farewell to the stage, to a supporting role as witness for the nineteenth-century Darwinians’ idea of the missing link, to a veritable efflorescence of walk-on parts, cameos, and star vehicles in twentieth-century psychoanalytic and social arguments about European expansion.2 The play has given us individual poems and paintings, not to speak of screen-plays for several film adaptations. The Tempest has been one of Shakespeare’s most adapted plays. Its stage history is concomitantly a history of the British theatre, from regularized comedy to semi-opera to pantomime to opera. It has had other lives, too, from its position in romantic ideas of Shakespeare’s biography and his so-called farewell to the stage, to a supporting role as witness for the nineteenth-century Darwinians’ idea of the missing link, to a veritable efflorescence of walk-on parts, cameos, and star vehicles in twentieth-century psychoanalytic and social arguments about European expansion.2 The play has given us individual poems and paintings, not to speak of screen-plays for several film adaptations.

  5. Auto-ignition modelling: analysis of the dilution effects by the unburnt gases and of the interactions with turbulence for diesel homogeneous charge compression ignition (HCCI) engines; Modelisation de l'auto-inflammation: analyse des effets de la dilution par les gaz brules et des interactions avec la turbulence dediee aux moteurs Diesel a charge homogene

    Energy Technology Data Exchange (ETDEWEB)

    Subramanian, G.

    2005-09-15

    Homogeneous Charge Compression Ignition (HCCI) is an alternative engine combustion process that offers the potential for substantial reductions in both NO{sub x} and particulate matter still providing high Diesel-like efficiencies. Combustion in HCCI mode takes place essentially by auto-ignition. It is mainly controlled by the chemical kinetics. It is therefore necessary to introduce detailed chemistry effects in combustion CFD codes in order to properly model the HCCI combustion process. The objective of this work is to develop an auto-ignition model including detailed chemical kinetics and its interactions with turbulence. Also, a comprehensive study has been performed to analyze the chemical influence of CO and H{sub 2} residual species on auto-ignition, which can be present in the exhaust gases. A new auto-ignition model, TKI-PDF (Tabulated Kinetics for Ignition - with turbulent mixing interactions through a pdf approach) dedicated to RANS 3D engine combustion CFD calculations is proposed. The TKI-PDF model is formulated in order to accommodate the detailed chemical kinetics of auto-ignition coupled with turbulence/chemistry interactions. The complete model development and its validation against experimental results are presented in two parts. The first part of this work describes the detailed chemistry input to the model. The second part is dedicated to the turbulent mixing description. A method based on a progress variable reaction rate tabulation is used. A look-up table for the progress variable reaction rates has been built through constant volume complex chemistry simulations. Instantaneous local reaction rates inside the CFD computational cell are then calculated by linear interpolation inside the look-up table depending on the local thermodynamic conditions. In order to introduce the turbulent mixing effects on auto-ignition, a presumed pdf approach is used. The model has been validated in different levels. First, the detailed kinetic approach was

  6. Ignition of Aluminum Particles and Clouds

    Energy Technology Data Exchange (ETDEWEB)

    Kuhl, A L; Boiko, V M

    2010-04-07

    Here we review experimental data and models of the ignition of aluminum (Al) particles and clouds in explosion fields. The review considers: (i) ignition temperatures measured for single Al particles in torch experiments; (ii) thermal explosion models of the ignition of single Al particles; and (iii) the unsteady ignition Al particles clouds in reflected shock environments. These are used to develop an empirical ignition model appropriate for numerical simulations of Al particle combustion in shock dispersed fuel explosions.

  7. Ignition circuit for combustion engines

    Energy Technology Data Exchange (ETDEWEB)

    Becker, H W

    1977-05-26

    The invention refers to the ignition circuit for combustion engines, which are battery fed. The circuit contains a transistor and an oscillator to produce an output voltage on the secondary winding of an output transformer to supply an ignition current. The plant is controlled by an interrupter. The purpose of the invention is to form such a circuit that improved sparks for ignition are produced, on the one hand, and that on the other hand, the plant can continue to function after loss of the oscillator. The problem is solved by the battery and the secondary winding of the output transformers of the oscillator are connected via a rectifier circuit to produce a resultant total voltage with the ignition coil from the battery voltage and the rectified pulsating oscillator output.

  8. Advanced ignition for automotive engines

    OpenAIRE

    Pineda, Daniel Ivan

    2017-01-01

    Spark plugs have been igniting combustible mixtures like those found in automotive engines for over a century, and the principles of the associated ignition techniques using thermal plasma (inductive or capacitive sparks) have remained relatively unchanged during that time. However, internal combustion engines are increasingly operating with boosted intake pressures (i.e. turbo- or super-charged) in order to maintain power output while simultaneously reducing engine size and weight, and they ...

  9. The National Ignition Facility Project

    International Nuclear Information System (INIS)

    Paisner, J.A.; Campbell, E.M.; Hogan, W.J.

    1994-01-01

    The mission of the National Ignition Facility is to achieve ignition and gain in inertial confinement fusion targets in the laboratory. The facility will be used for defense applications such as weapons physics and weapons effects testing, and for civilian applications such as fusion energy development and fundamental studies of matter at high temperatures and densities. This paper reviews the design, schedule, and costs associated with the construction project

  10. The National Ignition Facility Project

    International Nuclear Information System (INIS)

    Paisner, J.A.; Campbell, E.M.; Hogan, W.J.

    1994-01-01

    The mission of the National Ignition Facility is to achieve ignition and gain in ICF targets in the laboratory. The facility will be used for defense applications such as weapons physics and weapons effect testing, and for civilian applications such as fusion energy development and fundamental studies of matter at high temperatures and densities. This paper reviews the design, schedule and costs associated with the construction project

  11. The national ignition facility (NIF) : A path to fusion energy

    International Nuclear Information System (INIS)

    Moses, E. I.

    2007-01-01

    Fusion energy has long been considered a promising clean, nearly inexhaustible source of energy. Power production by fusion micro-explosions of inertial confinement fusion (ICF) targets has been a long term research goal since the invention of the first laser in 1960. The NIF is poised to take the next important step in the journey by beginning experiments researching ICF ignition. Ignition on NIF will be the culmination of over thirty years of ICF research on high-powered laser systems such as the Nova laser at LLNL and the OMEGA laser at the University of Rochester as well as smaller systems around the world. NIF is a 192 beam Nd-glass laser facility at LLNL that is more than 90% complete. The first cluster of 48 beams is operational in the laser bay, the second cluster is now being commissioned, and the beam path to the target chamber is being installed. The Project will be completed in 2009 and ignition experiments will start in 2010. When completed NIF will produce up to 1.8 MJ of 0.35 μm light in highly shaped pulses required for ignition. It will have beam stability and control to higher precision than any other laser fusion facility. Experiments using one of the beams of NIF have demonstrated that NIF can meet its beam performance goals. The National Ignition Campaign (NIC) has been established to manage the ignition effort on NIF. NIC has all of the research and development required to execute the ignition plan and to develop NIF into a fully operational facility. NIF will explore the ignition space, including direct drive, 2ω ignition, and fast ignition, to optimize target efficiency for developing fusion as an energy source. In addition to efficient target performance, fusion energy requires significant advances in high repetition rate lasers and fusion reactor technology. The Mercury laser at LLNL is a high repetition rate Nd-glass laser for fusion energy driver development. Mercury uses state-o-the art technology such as ceramic laser slabs and light

  12. Ignition inhibitors for cellulosic materials

    International Nuclear Information System (INIS)

    Alvares, N.J.

    1976-01-01

    By exposing samples to various irradiance levels from a calibrated thermal radiation source, the ignition responses of blackened alpha-cellulose and cotton cloth with and without fire-retardant additives were compared. Samples treated with retardant compounds which showed the most promise were then isothermally pyrolyzed in air for comparisons between the pyrolysis rates. Alpha-cellulose samples containing a mixture of boric acid, borax, and ammonium di-hydrogen phosphate could not be ignited by irradiances up to 4.0 cal cm -2 s-1 (16.7 W/cm 2 ). At higher irradiances the specimens ignited, but flaming lasted only until the flammable gases were depleted. Cotton cloth containing a polymeric retardant with the designation THPC + MM was found to be ignition-resistant to all irradiances below 7.0 cal cm -2 s -1 (29.3 W/cm 2 ). Comparison of the pyrolysis rates of the retardant-treated alpha-cellulose and the retardant-treated cotton showed that the retardant mechanism is qualitatively the same. Similar ignition-response measurements were also made with specimens exposed to ionizing radiation. It was observed that gamma radiation results in ignition retardance of cellulose, while irradiation by neutrons does not

  13. Place Branding

    DEFF Research Database (Denmark)

    Medway, Dominic; Swanson, Kathryn; Neirotti, Lisa Delpy

    2015-01-01

    Purpose: – The purpose of this paper is to report on a special session entitled “Place branding: Are we wasting our time?”, held at the American Marketing Association’s Summer Marketing Educators’ conference in 2014. Design/methodology/approach: – The report details the outcome of an Oxford......: – The outcome of the debate points towards a need for place brands to develop as more inclusive and organic entities, in which case it may be best for place practitioners to avoid creating and imposing a place brand and instead help shape it from the views of stakeholder constituencies. This shifts the notion...... of place branding towards an activity centred on “curation”. Originality/value: – The use of a competitive debating format as a means for exploring academic ideas and concepts in the place management field....

  14. WILDFIRE IGNITION RESISTANCE ESTIMATOR WIZARD SOFTWARE DEVELOPMENT REPORT

    Energy Technology Data Exchange (ETDEWEB)

    Phillips, M.; Robinson, C.; Gupta, N.; Werth, D.

    2012-10-10

    This report describes the development of a software tool, entitled “WildFire Ignition Resistance Estimator Wizard” (WildFIRE Wizard, Version 2.10). This software was developed within the Wildfire Ignition Resistant Home Design (WIRHD) program, sponsored by the U. S. Department of Homeland Security, Science and Technology Directorate, Infrastructure Protection & Disaster Management Division. WildFIRE Wizard is a tool that enables homeowners to take preventive actions that will reduce their home’s vulnerability to wildfire ignition sources (i.e., embers, radiant heat, and direct flame impingement) well in advance of a wildfire event. This report describes the development of the software, its operation, its technical basis and calculations, and steps taken to verify its performance.

  15. Fast ignition breakeven scaling

    International Nuclear Information System (INIS)

    Slutz, Stephen A.; Vesey, Roger Alan

    2005-01-01

    A series of numerical simulations have been performed to determine scaling laws for fast ignition break even of a hot spot formed by energetic particles created by a short pulse laser. Hot spot break even is defined to be when the fusion yield is equal to the total energy deposited in the hot spot through both the initial compression and the subsequent heating. In these simulations, only a small portion of a previously compressed mass of deuterium-tritium fuel is heated on a short time scale, i.e., the hot spot is tamped by the cold dense fuel which surrounds it. The hot spot tamping reduces the minimum energy required to obtain break even as compared to the situation where the entire fuel mass is heated, as was assumed in a previous study [S. A. Slutz, R. A. Vesey, I. Shoemaker, T. A. Mehlhorn, and K. Cochrane, Phys. Plasmas 7, 3483 (2004)]. The minimum energy required to obtain hot spot break even is given approximately by the scaling law E T = 7.5(ρ/100) -1.87 kJ for tamped hot spots, as compared to the previously reported scaling of E UT = 15.3(ρ/100) -1.5 kJ for untamped hotspots. The size of the compressed fuel mass and the focusability of the particles generated by the short pulse laser determines which scaling law to use for an experiment designed to achieve hot spot break even

  16. Ignition of hydrocarbon-air supersonic flow by volumetric ionization

    Science.gov (United States)

    Goldfeld, Marat A.; Pozdnyakov, George A.

    2015-11-01

    The paper describes the results of the electron-beam initiation of the combustion in the mixtures of hydrogen, natural gas or kerosene vapors with air. Electron beam characteristics were studied in closed volume with immobile gas. The researches included definition of an integrated current of an electronic beam, distribution of a current density and an estimation of average energy of electrons. Possibility of fuel mixtures ignition by means of this approach in the combustor at high velocity at the entrance was demonstrated. Experiments were carried out at Mach numbers of 4 and 5. Process of ignition and combustion under electron beam action was researched. It was revealed that ignition of mixture occurs after completion of electron gun operation. Data obtained have confirmed effectiveness of electron beam application for ignition of hydrogen and natural gas. The numerical simulation of the combustion of mixture in channel was carried out by means of ANSYS CFD 12.0 instrumentation on the basis of Reynolds averaged Navier-Stokes equation using SST/k-ω turbulence model. For combustion modeling, a detailed kinetic scheme with 38 reactions of 8 species was implemented taking into account finite rate chemistry. Computations have shown that the developed model allow to predict ignition of a mixture and flame propagation even at low flow temperatures.

  17. Influence of interface conditions on laser diode ignition of pyrotechnic mixtures: application to the design of an ignition device

    Energy Technology Data Exchange (ETDEWEB)

    Opdebeck, Frederic; Gillard, Philippe [Laboratoire Energetique Explosions et Structures de l' Universite d' Orleans, 63 boulevard de Lattre de Tassigny, 18020 cedex, Bourges (France); Radenac, D' Erwann [Laboratoire de combustion et de detonique, ENSMA, BP 109, 86960 cedex, Futuroscope (France)

    2003-01-01

    This paper treats of numerical modelling which simulates the laser ignition of pyrotechnic mixtures. The computation zone is divided into two fields. The first is used to take account of the heat loss with the outside. It can represent an optical fibre or a sapphire protective porthole. The second field represents the reactive tablet which absorbs the laser diode's beam. A specific feature of the model is that it incorporates a thermal contact resistance R{sub c} between the two computation fields. Through knowledge of the thermal, optical and kinetic properties, this code makes it possible to compute the ignition conditions. The latter are defined by the energy E{sub 50} and the time t{sub i} of ignition of any pyrotechnic mixture and for various ignition systems.This work was validated in the case of an ignition system consisting of a laser diode with an optical lens re-focussing system. The reactive tablet contains 62% by mass of iron and 38% by mass of KClO{sub 4}. Its porosity is 25.8%. After an evaluation of the laser's coefficient of absorption, the variations of the ignition parameters E{sub 50} and t{sub i} are studied as a function of the thermal contact resistance R{sub c}. Temperature profiles are obtained as a function of time and for various values of the thermal contact resistance R{sub c}. More fundamental observations are made concerning the position of the hot spot corresponding to priming. From this study, which concerns the heat exchange between the two media, several practical conclusions are given concerning the design of an ignition device. By evaluation of the thermal contact resistance R{sub c}, comparison with test results becomes possible and the results of the computations are in reasonable agreement with the test measurements. (authors)

  18. Better Place

    DEFF Research Database (Denmark)

    Rask, Morten; Bakke, Nikolas; Lindhøj, Jan

    Better Place is trying to reshape the automotive industry by shifting transportation from a dependency on oil to a reliance on environmentally friendly renewable energy. Better Place is developing an extensive infrastructure system that will utilise overcapacity in the production of wind power...... among others and that will drive the global transportation industry to becoming driven by electric vehicles (EVs). Better Place does this by selling its customers 'mileage' and a car without a battery. The case highlights the internationalisation process of Better Place from an international business...... perspective in order to encourage a discussion and debate about how Better Place can make their grand vision a reality in the future by overcoming the obstacles that historically have been challenging the rise of the EV industry. The case includes a historical background of the EV industry by using Denmark...

  19. Multimodal Friction Ignition Tester

    Science.gov (United States)

    Davis, Eddie; Howard, Bill; Herald, Stephen

    2009-01-01

    The multimodal friction ignition tester (MFIT) is a testbed for experiments on the thermal and mechanical effects of friction on material specimens in pressurized, oxygen-rich atmospheres. In simplest terms, a test involves recording sensory data while rubbing two specimens against each other at a controlled normal force, with either a random stroke or a sinusoidal stroke having controlled amplitude and frequency. The term multimodal in the full name of the apparatus refers to a capability for imposing any combination of widely ranging values of the atmospheric pressure, atmospheric oxygen content, stroke length, stroke frequency, and normal force. The MFIT was designed especially for studying the tendency toward heating and combustion of nonmetallic composite materials and the fretting of metals subjected to dynamic (vibrational) friction forces in the presence of liquid oxygen or pressurized gaseous oxygen test conditions approximating conditions expected to be encountered in proposed composite material oxygen tanks aboard aircraft and spacecraft in flight. The MFIT includes a stainless-steel pressure vessel capable of retaining the required test atmosphere. Mounted atop the vessel is a pneumatic cylinder containing a piston for exerting the specified normal force between the two specimens. Through a shaft seal, the piston shaft extends downward into the vessel. One of the specimens is mounted on a block, denoted the pressure block, at the lower end of the piston shaft. This specimen is pressed down against the other specimen, which is mounted in a recess in another block, denoted the slip block, that can be moved horizontally but not vertically. The slip block is driven in reciprocating horizontal motion by an electrodynamic vibration exciter outside the pressure vessel. The armature of the electrodynamic exciter is connected to the slip block via a horizontal shaft that extends into the pressure vessel via a second shaft seal. The reciprocating horizontal

  20. Review: laser ignition for aerospace propulsion

    Directory of Open Access Journals (Sweden)

    Steven A. O’Briant

    2016-03-01

    This paper aims to provide the reader an overview of advanced ignition methods, with an emphasis on laser ignition and its applications to aerospace propulsion. A comprehensive review of advanced ignition systems in aerospace applications is performed. This includes studies on gas turbine applications, ramjet and scramjet systems, and space and rocket applications. A brief overview of ignition and laser ignition phenomena is also provided in earlier sections of the report. Throughout the reading, research papers, which were presented at the 2nd Laser Ignition Conference in April 2014, are mentioned to indicate the vast array of projects that are currently being pursued.

  1. Design of ignition targets for the National Ignition Facility

    International Nuclear Information System (INIS)

    Haan, S.W.; Dittrich, T.R.; Marinak, M.M.; Hinkel, D.E.

    1999-01-01

    This is a brief update on the work being done to design ignition targets for the National Ignition Facility. Updates are presented on three areas of current activity : improvements in modeling, work on a variety of targets spanning the parameter space of possible ignition targets ; and the setting of specifications for target fabrication and diagnostics. Highlights of recent activity include : a simulation of the Rayleigh-Taylor instability growth on an imploding capsule, done in 3D on a 72degree by 72degree wedge, with enough zones to resolve modes out to 100 ; and designs of targets at 250eV and 350eV, as well as the baseline 300 eV ; and variation of the central DT gas density, which influences both the Rayleigh-Taylor growth and the smoothness of the DT ice layer

  2. Sausage instabilities in the electron current layer and its role in the concept of fast ignition

    International Nuclear Information System (INIS)

    Das, Amita; Jain, Neeraj; Kaw, Predhiman; Sengupta, Sudip

    2004-01-01

    The fast ignition concept of laser fusion utilizes hot electrons produced at the surface of the target by an incident intense laser pulse for the creation of the hot spot for ignition. As the hot electrons move inwards to the core of the precompressed target, the electrons from the background plasma provide a return shielding current. Three dimensional PIC simulations have shown that intense Weibel, tearing and coalescence instabilities take place which organize the current distribution into a few current filaments. In each of these filaments the central core region constitutes a current due to the fast electrons propagating inwards towards the pellet core, while the outer cylindrical shell region carries the return shielding current. The presence of instabilities and their subsequent nonlinear development can hinder the propagation of fast electrons towards the core influencing the location of the hot spot for ignition. Earlier studies showing the existence of sausage-like modes were carried out in the nonrelativistic limit and under the assumption of equal electron densities of the fast and the cold electrons. The fast electron density, in general, differs considerably from the background plasma density as it is dependent on the incident laser intensity. This paper incorporates relativistic effects and also studies the dependence of the growth rate on the fast electron density. Finally, nonlinear saturation of the instability and its impact on the stopping of the fast electron motion towards the core have also been investigated using numerical simulations. The simulations have, however, currently been carried out for non-relativistic dynamics. The results show that the sheared velocity profile of the channel gets flattened, causing an effective drop in the inward moving current. (author)

  3. Healthy Places

    Centers for Disease Control (CDC) Podcasts

    Every person has a stake in environmental public health. As the environment deteriorates, so does the physical and mental health of the people within it. Healthy places are those designed and built to improve the quality of life for all people who live, work, worship, learn, and play within their borders -- where every person is free to make choices amid a variety of healthy, available, accessible, and affordable options. The CDC recognizes significant health issues and places that are vital in developing the Healthy Places program and provides examples in this report.

  4. Progress Towards Ignition on the National Ignition Facility

    Science.gov (United States)

    Edwards, John

    2012-10-01

    Since completion of the National Ignition Facility (NIF) construction project in March 2009, a wide variety of diagnostics, facility infrastructure, and experimental platforms have been commissioned in pursuit of generating the conditions necessary to reach thermonuclear ignition in the laboratory via the inertial confinement approach. NIF's capabilities and infrastructure include over 50 X-ray, optical, and nuclear diagnostics systems and the ability to shoot cryogenic DT layered capsules. There are two main approaches to ICF: direct drive in which laser light impinges directly on a capsule containing a solid layer of DT fuel, and indirect drive in which the laser light is first converted to thermal X-rays. To date NIF has been conducting experiments using the indirect drive approach, injecting up to 1.8MJ of ultraviolet light (0.35 micron) into 1 cm scale cylindrical gold or gold-coated uranium, gas-filled hohlraums, to implode 1mm radius plastic capsules containing solid DT fuel layers. In order to achieve ignition conditions the implosion must be precisely controlled. The National Ignition Campaign (NIC), an international effort with the goal of demonstrating thermonuclear burn in the laboratory, is making steady progress toward this. Utilizing precision pulse-shaping experiments in early 2012 the NIC achieve fuel rhoR of approximately 1.2 gm/cm^2 with densities of around 600-800 g/cm^3 along with neutron yields within about a factor of 5 necessary to enter a regime in which alpha particle heating will become important. To achieve these results, experimental platforms were developed to carefully control key attributes of the implosion. This talk will review NIF's capabilities and the progress toward ignition, as well as the physics of ignition targets on NIF and on other facilities. Acknowledgement: this work performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.

  5. Ignitability of hydrogen/oxygen/diluent mixtures in the presence of hot surfaces

    International Nuclear Information System (INIS)

    Kumar, R.K.; Koroll, G.W.

    1995-01-01

    In the licensing process for CANDU nuclear power stations it is necessary to demonstrate tolerance to a wide range of low-probability accidents. These include loss of moderator accidents that may lead to the formation of flammable mixtures of deuterium, oxygen, helium, and steam in the reactor calandria vessel. Uncovered adjuster or control rods are considered as possible sources of ignition when a flammable mixture is present. A knowledge of the minimum hot-surface temperature required for ignition is important in assessing the reactor safety. These hot surface temperatures were measured using electrically heated adjuster rod simulators in a large spherical vessel (2.3-m internal diameter). Whereas the effects of geometry on ignition temperature were studied in the large-scale apparatus, some of the effects, such as those produced by a strong radiation field, were studied using a small-scale apparatus. Investigations carried our over a range of hydrogen and diluent concentrations indicated that, although the ignition temperatures were fairly insensitive to the hydrogen concentration, they were strongly affected by the presence of steam The addition of 30% steam to a dry combustible mixture increased the minimum surface temperature required for ignition by approximates 100 degrees C of the diluents investigated, steam had the most effect on ignition. The effect of initial temperature of the mixture on the ignition temperature was small, whereas the effect of initial pressure was significant. The effect of substituting deuterium for hydrogen on ignition temperature was small. The effect of a high-intensity gamma-radiation field on the minimum hot-surface temperature required for ignition was investigated using a 2-dm 3 ignition vessel placed in a linear accelerator. Radiation had no measurable effect on ignition temperature

  6. Application of Alcohols to Dual - Fuel Feeding the Spark-Ignition and Self-Ignition Engines

    Directory of Open Access Journals (Sweden)

    Stelmasiak Zdzisław

    2014-10-01

    Full Text Available This paper concerns analysis of possible use of alcohols for the feeding of self - ignition and spark-ignition engines operating in a dual- fuel mode, i.e. simultaneously combusting alcohol and diesel oil or alcohol and petrol. Issues associated with the requirements for application of bio-fuels were presented with taking into account National Index Targets, bio-ethanol production methods and dynamics of its production worldwide and in Poland. Te considerations are illustrated by results of the tests on spark- ignition and self- ignition engines fed with two fuels: petrol and methanol or diesel oil and methanol, respectively. Te tests were carried out on a 1100 MPI Fiat four- cylinder engine with multi-point injection and a prototype collector fitted with additional injectors in each cylinder. Te other tested engine was a SW 680 six- cylinder direct- injection diesel engine. Influence of a methanol addition on basic operational parameters of the engines and exhaust gas toxicity were analyzed. Te tests showed a favourable influence of methanol on combustion process of traditional fuels and on some operational parameters of engines. An addition of methanol resulted in a distinct rise of total efficiency of both types of engines at maintained output parameters (maximum power and torque. In the same time a radical drop in content of hydrocarbons and nitrogen oxides in exhaust gas was observed at high shares of methanol in feeding dose of ZI (petrol engine, and 2-3 fold lower smokiness in case of ZS (diesel engine. Among unfavourable phenomena, a rather insignificant rise of CO and NOx content for ZI engine, and THC and NOx - for ZS engine, should be numbered. It requires to carry out further research on optimum control parameters of the engines. Conclusions drawn from this work may be used for implementation of bio-fuels to feeding the combustion engines.

  7. Enhanced Model for Fast Ignition

    Energy Technology Data Exchange (ETDEWEB)

    Mason, Rodney J. [Research Applications Corporation, Los Alamos, NM (United States)

    2010-10-12

    Laser Fusion is a prime candidate for alternate energy production, capable of serving a major portion of the nation's energy needs, once fusion fuel can be readily ignited. Fast Ignition may well speed achievement of this goal, by reducing net demands on laser pulse energy and timing precision. However, Fast Ignition has presented a major challenge to modeling. This project has enhanced the computer code ePLAS for the simulation of the many specialized phenomena, which arise with Fast Ignition. The improved code has helped researchers to understand better the consequences of laser absorption, energy transport, and laser target hydrodynamics. ePLAS uses efficient implicit methods to acquire solutions for the electromagnetic fields that govern the accelerations of electrons and ions in targets. In many cases, the code implements fluid modeling for these components. These combined features, "implicitness and fluid modeling," can greatly facilitate calculations, permitting the rapid scoping and evaluation of experiments. ePLAS can be used on PCs, Macs and Linux machines, providing researchers and students with rapid results. This project has improved the treatment of electromagnetics, hydrodynamics, and atomic physics in the code. It has simplified output graphics, and provided new input that avoids the need for source code access by users. The improved code can now aid university, business and national laboratory users in pursuit of an early path to success with Fast Ignition.

  8. Sausage instabilities in electron current channels and the problem of fast ignition

    International Nuclear Information System (INIS)

    Das, A.

    2002-01-01

    In the fast ignition concept of laser fusion, an intense picosecond laser pulse incident on an overdense pellet is absorbed by nonlinear mechanisms and gets converted into inward propagating fast electron currents. PIC simulations show that the return shielding currents due to cold plasma interact with the incoming currents and intense Weibel, tearing and coalescence instabilities take place, which organize the current into a few current channels. The stability of these current channels is thus a topic of great interest. We have carried out linear and nonlinear studies of 2 - dimensional sausage instabilities of a slab model of the current channels in the framework of electron magnetohydrodynamic fluid approximation. The analytic calculations and numerical simulations for some simple velocity profiles show the presence of linear instability driven by velocity shear. Nonlinear studies on the saturation of instabilities and their reaction back on the relaxation of the velocity profile have also been made. A discussion of the consequences of such EMHD turbulence induced relaxation and stopping of fast electrons, for the fast ignition concept will be presented. (author)

  9. Laser plasma physics in shock ignition – transition from collisional to collisionless absorption

    Directory of Open Access Journals (Sweden)

    Klimo O.

    2013-11-01

    Full Text Available Shock Ignition is considered as a relatively robust and efficient approach to inertial confinement fusion. A strong converging shock, which is used to ignite the fuel, is launched by a high power laser pulse with intensity in the range of 1015 − 1016 W/cm2 (at the wavelength of 351 nm. In the lower end of this intensity range the interaction is dominated by collisions while the parametric instabilities are playing a secondary role. This is manifested in a relatively weak reflectivity and efficient electron heating. The interaction is dominated by collective effects at the upper edge of the intensity range. The stimulated Brillouin and Raman scattering (SBS and SRS respectively take place in a less dense plasma and cavitation provides an efficient collisionless absorption mechanism. The transition from collisional to collisionless absorption in laser plasma interactions at higher intensities is studied here with the help of large scale one-dimensional Particle-in-Cell (PIC simulations. The relation between the collisional and collisionless processes is manifested in the energy spectrum of electrons transporting the absorbed laser energy and in the spectrum of the reflected laser light.

  10. Place (National)

    Data.gov (United States)

    Department of Transportation — This map layer includes cities and towns in the United States, Puerto Rico, and the U.S. Virgin Islands (NTAD). A city or town is a place with a recorded population,...

  11. Taking antacids

    Science.gov (United States)

    Heartburn - antacids; Reflux - antacids; GERD - antacids ... Antacids are a good treatment for heartburn that occurs once in a while. Take antacids about 1 hour after eating or when you have heartburn. If you are taking ...

  12. Options for an ignited tokamak

    International Nuclear Information System (INIS)

    Sheffield, J.

    1984-02-01

    It is expected that the next phase of the fusion program will involve a tokamak with the goals of providing an ignited plasma for pulses of hundreds of seconds. A simple model is described in this memorandum which establishes the physics conditions for such a self-sustaining plasma, for given ion and electron thermal diffusivities, in terms of R/a, b/a, I, B/q, epsilon β/sub p/, anti T/sub i/, and anti T/sub e//anti T/sub i/. The model is used to produce plots showing the wide range of tokamaks that may ignite or have a given ignition margin. The constraints that limit this range are discussed

  13. Electron transport and shock ignition

    Energy Technology Data Exchange (ETDEWEB)

    Bell, A R; Tzoufras, M, E-mail: t.bell1@physics.ox.ac.uk [Clarendon Laboratory, University of Oxford, Parks Road, Oxford OX1 3PU (United Kingdom)

    2011-04-15

    Inertial fusion energy (IFE) offers one possible route to commercial energy generation. In the proposed 'shock ignition' route to fusion, the target is compressed at a relatively low temperature and then ignited using high intensity laser irradiation which drives a strong converging shock into the centre of the fuel. With a series of idealized calculations we analyse the electron transport of energy into the target, which produces the pressure responsible for driving the shock. We show that transport in shock ignition lies near the boundary between ablative and heat front regimes. Moreover, simulations indicate that non-local effects are significant in the heat front regime and might lead to increased efficiency by driving the shock more effectively and reducing heat losses to the plasma corona.

  14. Linear induction accelerator requirements for ion fast ignition

    International Nuclear Information System (INIS)

    Logan, G.

    1998-01-01

    induction linacs, the purpose of this memo is to explore possible new features and characteristic parameters that induction linacs would need to meet the stringent requirements for beam quality and compression (sufficiently low longitudinal and transverse thermal spread) for ion driven fast ignition. Separately, Ed Lee at LBNL is looking at heavy-ion synchrotrons to meet similar fast ignition requirements. Parameters relating to cost (e.g, total beam-line length and transport quads, total core volt-seconds and power switching) have to be considered in addition to meeting the challenging beam quality requirements for fast ignition compared to conventional HIF. The aim of this preliminary study is to motivate, after critical debate, taking a next step to do more detailed designs, particle simulations, and experimental tests of the most critical accelerator elements and focusing optics, to further assess the feasibility of ion-driven fast ignition

  15. Flow Friction or Spontaneous Ignition?

    Science.gov (United States)

    Stoltzfus, Joel M.; Gallus, Timothy D.; Sparks, Kyle

    2012-01-01

    "Flow friction," a proposed ignition mechanism in oxygen systems, has proved elusive in attempts at experimental verification. In this paper, the literature regarding flow friction is reviewed and the experimental verification attempts are briefly discussed. Another ignition mechanism, a form of spontaneous combustion, is proposed as an explanation for at least some of the fire events that have been attributed to flow friction in the literature. In addition, the results of a failure analysis performed at NASA Johnson Space Center White Sands Test Facility are presented, and the observations indicate that spontaneous combustion was the most likely cause of the fire in this 2000 psig (14 MPa) oxygen-enriched system.

  16. PITR: Princeton Ignition Test Reactor

    International Nuclear Information System (INIS)

    1978-12-01

    The principal objectives of the PITR - Princeton Ignition Test Reactor - are to demonstrate the attainment of thermonuclear ignition in deuterium-tritium, and to develop optimal start-up techniques for plasma heating and current induction, in order to determine the most favorable means of reducing the size and cost of tokamak power reactors. This report describes the status of the plasma and engineering design features of the PITR. The PITR geometry is chosen to provide the highest MHD-stable values of beta in a D-shaped plasma, as well as ease of access for remote handling and neutral-beam injection

  17. Confinement of ignition and yield on the National Ignition Facility

    International Nuclear Information System (INIS)

    Tobin, M.; Karpenko, V.; Foley, D.; Anderson, A.; Burnham, A.; Reitz, T.; Latkowski, J.; Bernat, T.

    1996-01-01

    The National Ignition Facility Target Areas and Experimental Systems has reached mid-Title I design. Performance requirements for the Target Area are reviewed and design changes since the Conceptual Design Report are discussed. Development activities confirm a 5-m radius chamber and the viability of a boron carbide first wall. A scheme for cryogenic target integration with the NIF Target Area is presented

  18. Büroo Ignite = Ignite office / Priit Põldme, Reet Sepp

    Index Scriptorium Estoniae

    Põldme, Priit, 1971-

    2013-01-01

    Büroo Ignite (Tatari 25, Tallinn) sisekujundusest. Sisearhitektid Priit Põldme ja Reet Sepp (SAB Joonprojekt). Arhitektid Heiki Taras ja Ahti Luhaäär (Arhitektibüroo Pilter ja Taras). Sisearhitekti ja ESLi aastapreemiate žürii esimehe Kaido Kivi arvamus

  19. The national ignition facility: path to ignition in the laboratory

    International Nuclear Information System (INIS)

    Moses, E.I.; Bonanno, R.E.; Haynam, C.A.; Kauffman, R.L.; MacGowan, B.J.; Patterson Jr, R.W.; Sawicki, R.H.; Van Wonterghem, B.M.

    2007-01-01

    The National Ignition Facility (NIF) is a 192-beam laser facility presently under construction at Lawrence Livermore National Laboratory. When completed, NIF will be a 1.8-MJ, 500-TW ultraviolet laser system. Its missions are to obtain fusion ignition of deuterium-tritium plasmas in ICF (Inertial Confinement Fusion) targets and to perform high energy density experiments in support of the U.S. nuclear weapons stockpile. The NIF facility will consist of 2 laser bays, 4 capacitor areas, 2 laser switchyards, the target area and the building core. The laser is configured in 4 clusters of 48 beams, 2 in each laser bay. Four of the NIF beams have been already commissioned to demonstrate laser performance and to commission the target area including target and beam alignment and laser timing. During this time, NIF has demonstrated on a single-beam basis that it will meet its performance goals and has demonstrated its precision and flexibility for pulse shaping, pointing, timing and beam conditioning. It also performed 4 important experiments for ICF and High Energy Density Science. Presently, the project is installing production hardware to complete the project in 2009 with the goal to begin ignition experiments in 2010. An integrated plan has been developed including the NIF operations, user equipment such as diagnostics and cryogenic target capability, and experiments and calculations to meet this goal. This talk will provide NIF status, the plan to complete NIF, and the path to ignition. (authors)

  20. Surface breakdown igniter for mercury arc devices

    Science.gov (United States)

    Bayless, John R.

    1977-01-01

    Surface breakdown igniter comprises a semiconductor of medium resistivity which has the arc device cathode as one electrode and has an igniter anode electrode so that when voltage is applied between the electrodes a spark is generated when electrical breakdown occurs over the surface of the semiconductor. The geometry of the igniter anode and cathode electrodes causes the igniter discharge to be forced away from the semiconductor surface.

  1. Ignition and spread of electrical wire fires

    OpenAIRE

    Huang, Xinyan

    2012-01-01

    Ignition of electrical wires by external heating is investigated in order to gain a better understanding of the initiation of electrical-wire fires. An ignition-to- spread model is developed to systematically explain ignition and the following transition to spread. The model predicts that for a higher-conductance wire it is more difficult to achieve ignition and the weak flame may extinguish during the transition phase because of a large conductive heat loss along the wire core. Wires with tw...

  2. Healthy Places

    Centers for Disease Control (CDC) Podcasts

    2007-04-10

    Every person has a stake in environmental public health. As the environment deteriorates, so does the physical and mental health of the people within it. Healthy places are those designed and built to improve the quality of life for all people who live, work, worship, learn, and play within their borders -- where every person is free to make choices amid a variety of healthy, available, accessible, and affordable options. The CDC recognizes significant health issues and places that are vital in developing the Healthy Places program and provides examples in this report.  Created: 4/10/2007 by CDC National Center for Environmental Health.   Date Released: 4/13/2007.

  3. Designed Places

    DEFF Research Database (Denmark)

    Stender, Marie

    The 2008 financial crisis has left traces in the built environment of Copenhagen like many other places: Building projects are left unfinished or their function or finish is changed due to new economic circumstances. An ethnographic exploration of these traces exposes central aspects of what is a......, and when the ceilings leak water, the residents suspect it to be a consequence of the crisis. The paper discusses how market forces interact with the material surroundings we inhabit and explores the relationship between controlled and uncontrollable in the design of places....

  4. Structure ignition assessment model (SIAM)\\t

    Science.gov (United States)

    Jack D. Cohen

    1995-01-01

    Major wildland/urban interface fire losses, principally residences, continue to occur. Although the problem is not new, the specific mechanisms are not well known on how structures ignite in association with wildland fires. In response to the need for a better understanding of wildland/urban interface ignition mechanisms and a method of assessing the ignition risk,...

  5. 14 CFR 33.69 - Ignitions system.

    Science.gov (United States)

    2010-01-01

    ... STANDARDS: AIRCRAFT ENGINES Design and Construction; Turbine Aircraft Engines § 33.69 Ignitions system. Each..., except that only one igniter is required for fuel burning augmentation systems. [Amdt. 33-6, 39 FR 35466... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Ignitions system. 33.69 Section 33.69...

  6. Fast fission assisted ignition of thermonuclear microexplosions

    International Nuclear Information System (INIS)

    Winterberg, F.

    2006-01-01

    It is shown that the requirements for fast ignition of thermonuclear microexplosions can be substantially relaxed if the deuterium-tritium (DT) hot spot is placed inside a shell of U-238 (Th-232). An intense laser - or particle beam-projected into the shell leads to a large temperature gradient between the hot DT and the cold U-238 (Th-232), driving thermomagnetic currents by the Nernst effect, with magnetic fields large enough to entrap within the hot spot the α-particles of the DT fusion reaction. The fast fission reactions in the U-238 (Th-232) shell implode about 1/2 of the shell onto the DT, increasing its density and reaction rate. With the magnetic field generated by the Nernst effect, there is no need to connect the target to a large current carrying transmission line, as it is required for magnetized target fusion, solving the so-called ''stand off'' problem for thermonuclear microexplosions. (orig.)

  7. Nonlinear control of a spark ignition engine

    Energy Technology Data Exchange (ETDEWEB)

    Bidan, P [Centre National de la Recherche Scientifique (CNRS), 31 - Toulouse (France); Boverie, S; Chaumerliac, V [Siemens AutomotiveSA, MIRGAS Laboratory, 31 - Toulouse (France)

    1994-12-31

    This paper describes the improvements which can be made to spark ignition engine by extensive use of automatic control. Particular emphasis is placed on fast transient phases produced by simultaneous action on the throttle and the electronic fuel injection device. The aim is to achieve better performance for the fuel/air ratio regulation system, thereby improving engine efficiency and exhaust emission during these transient phases. The authors begin by presenting an average dynamic model of the intake manifold validated on an engine test bench and goes on to develop a closed-loop system controlling average pressure in the intake manifold using the reference tracking model method. The air supply control system is combined with a predictor to compensate for delays in the injection procedure. The paper concludes with a comparison between the results obtained using simulation and those obtained experimentally from the engine. (author) 10 refs.

  8. Secret Places.

    Science.gov (United States)

    Ridolfi, Kerry

    1997-01-01

    Argues that children are as deep as the ocean, with secret places inside of them waiting to be opened. Notes that it is powerful for students to learn they can make sense of the world through words, and describes inviting them into poetry as they read poetry, create poetry packets, and write and revise poems. (SR)

  9. Envisioning place

    DEFF Research Database (Denmark)

    Schmidt, Garbi; Glick Schiller, Nina

    2016-01-01

    together, the articles contribute to an emerging relational social science by approaching urban sociabilities through four interrelated parameters: (1) a concept of place-making situated within trajectories of differential and multiscalar power; (2) a discursive analysis of narratives and silences...

  10. Plasma ignition of LOVA propellants

    NARCIS (Netherlands)

    Driel, C.A. van; Boluijt, A.G.; Schilt, A.

    2010-01-01

    Ignition experiments were performed using a gun simulator which is equipped with a burst disk. This equipment facilitates the application of propellant loading densities which are comparable to those applied in regular ammunitions. For this study the gun simulator was equipped with a plasma jet

  11. AC ignition of HID lamps

    NARCIS (Netherlands)

    Sobota, A.; Kanters, J.H.M.; Manders, F.; Veldhuizen, van E.M.; Haverlag, M.

    2010-01-01

    Our aim was to examine the starting behaviour of mid-pressure argon discharges in pin-pin (point-to-point) geometry, typically used in HID lamps. We focused our work on AC ignition of 300 and 700 mbar Ar discharges in Philips 70W standard burners. Frequency was varied between 200 kHz and 1 MHz. In

  12. Discharge ignition near a dielectric

    NARCIS (Netherlands)

    Sobota, A.; Veldhuizen, van E.M.; Stoffels, W.W.

    2008-01-01

    Electrical breakdown in noble gas near a dielectric is an important issue in lighting industry. In order to investigate the influence of the dielectric on the ignition process, we perform measurements in argon, with pressure varying from 0.1 to 1 bar, using a pin–pin electrode geometry. Here, we

  13. Tank farm potential ignition sources

    International Nuclear Information System (INIS)

    Scaief, C.C. III.

    1996-01-01

    This document identifies equipment, instrumentation, and sensors that are located in-tank as well as ex-tank in areas that may have communication paths with the tank vapor space. For each item, and attempt is made to identify the potential for ignition of flammable vapors using a graded approach. The scope includes all 177 underground storage tanks

  14. Ignition and burn control in tokamak plasmas

    International Nuclear Information System (INIS)

    Borrass, K.; Gruber, O.; Lackner, K.; Minardi, E.; Neuhauser, J.; Wilhelm, R.; Wunderlich, R.; Bromberg, L.; Cohn, D.R.

    1981-01-01

    Different schemes for the control of the thermal instability in an ignited fusion reactor are analysed by zero- and one-dimensional models. Passive stabilization methods considered are ripple-enhanced ion heat conduction, the effect of the major-radius variation of the plasma column in a time-independent vertical field, and the combination of both effects, including the spatial variation of the toroidal-ripple amplitude. Active control methods analysed are high-Q-driven operation and feedback-controlled major-radius variation following different scenarios. One-dimensional analyses taking into account only conductive losses show the existence of a single unstable mode in the energy balance, justifying, under these assumptions, the study of only global control. (author)

  15. Desensitizing nano powders to electrostatic discharge ignition

    International Nuclear Information System (INIS)

    Steelman, Ryan; Daniels, Michael A.

    2015-01-01

    Electrostatic discharge (ESD) is a main cause for ignition in powder media ranging from grain silos to fireworks. Nanoscale particles are orders of magnitude more ESD ignition sensitive than their micron scale counterparts. This study shows that at least 13 vol. % carbon nanotubes (CNT) added to nano-aluminum and nano-copper oxide particles (nAl + CuO) eliminates ESD ignition sensitivity. The CNT act as a conduit for electric energy and directs electric charge through the powder to desensitize the reactive mixture to ignition. For nanoparticles, the required CNT concentration for desensitizing ESD ignition acts as a diluent to quench energy propagation.

  16. Places Connected:

    DEFF Research Database (Denmark)

    Hansen, Annette Skovsted

    This paper argues that development assistance contributed to the globalization of the 20th century by financing truly global networks of people. By focusing on the networks financed by development assistance bound by the national histories of Denmark and Japan, I illustrate how the people who...... experiences of place, however, when it is often the same people who experience many different places? Along with many other so-called donors in the 1950s, Denmark and Japan chose to invest in the education of own and other nationals involved in development and thereby financed personal connections between...... individuals throughout the world. Development assistance , where there are two or three links only between a Bangladeshi farmer, a street child in Sao Paolo and the President of the United States, the Queen of Denmark, or a suburban house wife in Japan, who has never left the Osaka area, but mothered a United...

  17. Places available**

    CERN Multimedia

    2003-01-01

    If you wish to participate in one of the following courses, please discuss with your supervisor and apply electronically directly from the course description pages that can be found on the Web at: http://www.cern.ch/Training/ or fill in an "application for training" form available from your Divisional Secretariat or from your DTO (Divisional Training Officer). Applications will be accepted in the order of their receipt. TECHNICAL TRAINING Monique Duval tel. 74924 technical.training@cern.ch ** The number of places available may vary. Please check our Web site to find out the current availability. Places are available in the following courses: ACCESS 2000 - niveau 1 : 13 & 14.11.03 (2 jours) C++ for Particle Physicists : 17 – 21.11.03 (6 X 3-hour lectures) Programmation automate Schneider TSX Premium – niveau 2 : 18 – 21.11.03 (4 jours) JAVA 2 Enterprise Edition – Part 1 : WEB Applications : 20 & ...

  18. Places available

    CERN Multimedia

    2004-01-01

    If you wish to participate in one of the following courses, please discuss with your supervisor and apply electronically directly from the course description pages that can be found on the Web at: http://www.cern.ch/Training/ or fill in an "application for training" form available from your Divisional Secretariat or from your DTO (Divisional Training Officer). Applications will be accepted in the order of their receipt. Places available The number of places available may vary. Please check our Web site to find out the current availability. Places are available in the following courses : Introduction à Outlook : 19.8.2004 (1 journée) Outlook (short course I) : E-mail : 31.8.2004 (2 hours, morning) Outlook (short course II) : Calendar, Tasks and Notes : 31.8.2004 (2 hours, afternoon) Instructor-led WBTechT Study or Follow-up for Microsoft Applications : 7.9.2004 (morning) Outlook (short course III) : Meetings and Delegation : 7.9.2004 (2 hours, afternoon) Introduction ...

  19. Places disponibles*/Places available **

    CERN Multimedia

    2003-01-01

    Des places sont disponibles dans les cours suivants : Places are available in the following course : Java 2 Enterprise Edition - Part 2 : Enterprise JavaBeans : 20 - 22.1.03 (3 days) Introduction to PVSS : 27.1.03 (Afternoon) free course but registration necessary Basic PVSS : 28 - 30.1.03 (3 days) MAGNE-03 - Magnétisme pour l'électrotechnique : 28 - 30.1.03 (3 jours) MAGNE-03 - Magnetism for Technical Electronics : 11 - 13.2.03 (3 days) AutoCAD 2002 - niveau 1 : 24, 25.2 et 3, 4.3.03 (4 jours) AutoCAD 2002 - niveau 2 : 10 & 11.3.03 (2 jours) C++ for Particle Physicists : 10 - 14.3.03 (6 X 3 hour lectures) AutoCAD Mechanical 6 PowerPack (F) : 12, 13, 17, 18, 24 & 25.3.03 (6 jours) * Etant donné le délai d'impression du Bulletin, ces places peuvent ne plus être disponibles au moment de sa parution. Veuillez consulter notre site Web pour avoir la dernière mise à jour. ** The number of places available may vary. Please check our Web site to find out the current availability. Si vous désirez ...

  20. Physical studies of fast ignition in China

    International Nuclear Information System (INIS)

    He, X T; Cai, Hong-bo; Wu, Si-zhong; Cao, Li-hua; Zhang, Hua; He, Ming-qing; Chen, Mo; Wu, Jun-feng; Zhou, Cang-tao; Zhou, Wei-Min; Shan, Lian-qiang; Wang, Wei-wu; Zhang, Feng; Bi, Bi; Zhao, Zong-qing; Gu, Yu-qiu; Zhang, Bao-han; Wang, Wei; Fang, Zhi-heng; Lei, An-le

    2015-01-01

    Fast ignition approach to inertial confinement fusion is one of the important goals today, in addition to central hot spot ignition in China. The SG-IIU and PW laser facilities are coupled to investigate the hot spot formation for fast ignition. The SG-III laser facility is almost completed and will be coupled with tens kJ PW lasers for the demonstration of fast ignition. In recent years, for physical studies of fast ignition, we have been focusing on the experimental study of implosion symmetry, M-band radiation preheating and mixing, advanced fast ignition target design, and so on. In addition, the modeling capabilities and code developments enhanced our ability to perform the hydro-simulation of the compression implosion, and the particle-in-cell (PIC) and hybrid-PIC simulation of the generation, transport and deposition of relativistic electron beams. Considerable progress has been achieved in understanding the critical issues of fast ignition. (paper)

  1. A polar-drive shock-ignition design for the National Ignition Facility

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, K. S.; McKenty, P. W.; Collins, T. J. B.; Craxton, R. S.; Delettrez, J. A.; Marozas, J. A.; Skupsky, S.; Shvydky, A. [Laboratory for Laser Energetics, University of Rochester, 250 East River Road, Rochester, New York 14623 (United States); Betti, R. [Laboratory for Laser Energetics, University of Rochester, 250 East River Road, Rochester, New York 14623 (United States); Fusion Science Center, University of Rochester, Rochester, New York 14623 (United States); Departments of Mechanical Engineering and Physics, University of Rochester, Rochester, New York 14627 (United States); Hohenberger, M.; Theobald, W.; Lafon, M.; Nora, R. [Laboratory for Laser Energetics, University of Rochester, 250 East River Road, Rochester, New York 14623 (United States); Fusion Science Center, University of Rochester, Rochester, New York 14623 (United States)

    2013-05-15

    Shock ignition [R. Betti et al., Phys. Rev. Lett. 98, 155001 (2007)] is being pursued as a viable option to achieve ignition on the National Ignition Facility (NIF). Shock-ignition target designs use a high-intensity laser spike at the end of a low-adiabat assembly pulse to launch a spherically convergent strong shock to ignite the hot spot of an imploding capsule. A shock-ignition target design for the NIF is presented. One-dimensional simulations indicate an ignition threshold factor of 4.1 with a gain of 58. A polar-drive beam-pointing configuration for shock-ignition experiments on the NIF at 750 kJ is proposed. The capsule design is shown to be robust to the various one- and two-dimensional effects and nonuniformities anticipated on the NIF. The target is predicted to ignite with a gain of 38 when including all anticipated levels of nonuniformity and system uncertainty.

  2. Shock ignition targets: gain and robustness vs ignition threshold factor

    Science.gov (United States)

    Atzeni, Stefano; Antonelli, Luca; Schiavi, Angelo; Picone, Silvia; Volponi, Gian Marco; Marocchino, Alberto

    2017-10-01

    Shock ignition is a laser direct-drive inertial confinement fusion scheme, in which the stages of compression and hot spot formation are partly separated. The hot spot is created at the end of the implosion by a converging shock driven by a final ``spike'' of the laser pulse. Several shock-ignition target concepts have been proposed and relevant gain curves computed (see, e.g.). Here, we consider both pure-DT targets and more facility-relevant targets with plastic ablator. The investigation is conducted with 1D and 2D hydrodynamic simulations. We determine ignition threshold factors ITF's (and their dependence on laser pulse parameters) by means of 1D simulations. 2D simulations indicate that robustness to long-scale perturbations increases with ITF. Gain curves (gain vs laser energy), for different ITF's, are generated using 1D simulations. Work partially supported by Sapienza Project C26A15YTMA, Sapienza 2016 (n. 257584), Eurofusion Project AWP17-ENR-IFE-CEA-01.

  3. Tritium and ignition target management at the National Ignition Facility.

    Science.gov (United States)

    Draggoo, Vaughn

    2013-06-01

    Isotopic mixtures of hydrogen constitute the basic fuel for fusion targets of the National Ignition Facility (NIF). A typical NIF fusion target shot requires approximately 0.5 mmoles of hydrogen gas and as much as 750 GBq (20 Ci) of 3H. Isotopic mix ratios are specified according to the experimental shot/test plan and the associated test objectives. The hydrogen isotopic concentrations, absolute amounts, gas purity, configuration of the target, and the physical configuration of the NIF facility are all parameters and conditions that must be managed to ensure the quality and safety of operations. An essential and key step in the preparation of an ignition target is the formation of a ~60 μm thick hydrogen "ice" layer on the inner surface of the target capsule. The Cryogenic Target Positioning System (Cryo-Tarpos) provides gas handling, cyro-cooling, x-ray imaging systems, and related instrumentation to control the volumes and temperatures of the multiphase (solid, liquid, and gas) hydrogen as the gas is condensed to liquid, admitted to the capsule, and frozen as a single spherical crystal of hydrogen in the capsule. The hydrogen fuel gas is prepared in discrete 1.7 cc aliquots in the LLNL Tritium Facility for each ignition shot. Post-shot hydrogen gas is recovered in the NIF Tritium Processing System (TPS). Gas handling systems, instrumentation and analytic equipment, material accounting information systems, and the shot planning systems must work together to ensure that operational and safety requirements are met.

  4. Taking Stock.

    Science.gov (United States)

    Merriam, Sharan B.

    1993-01-01

    A complete theory of adult learning must take into consideration the learner, learning process, and context. Andragogy, self-directed learning, consciousness, critical theory, feminism, transformational learning, and situated cognition contribute to understanding of this complex phenomenon. (SK)

  5. Planned place of birth

    DEFF Research Database (Denmark)

    Overgaard, Charlotte; Coxon, Kirstie; Stewart, Mary

    Title Planned place of birth: issues of choice, access and equity. Outline In Northern European countries, giving birth is generally safe for healthy women with uncomplicated pregnancies, and their babies. However, place of birth can affect women’s outcomes and experiences of birth. Whilst tertiary...... countries, maternity care is provided free to women, through public financing of health care; universal access to care is therefore secured. Nevertheless, different models of care exist, and debates about the appropriateness of providing maternity care in different settings take place in both countries...... in Denmark Coxon K et al: Planned place of birth in England: perceptions of accessing obstetric units, midwife led units and home birth amongst women and their partners. How these papers interrelate These papers draw upon recent research in maternity care, undertaken in Denmark and in England. In both...

  6. Places available**

    CERN Multimedia

    Places are available in the following courses: Hands-on Introduction to Python Programming: 11-13.08.2003 (3 days) Introduction to the CERN Engineering Data Management System (EDMS): 26.08.2003 (1 day) The CERN Engineering Data Management System (EDMS) for Engineers: 27.08.2003 (1 day) CLEAN-2002 : Travailler en salle blanche : 4.09.2003 (une demi-journée) AutoCAD 2002 - Level 1: 4, 5, 15, 16.09.2003 (2 x 2 days) AutoCAD Mechanical 6 PowerPack : 17, 18, 25, 26.09.2003 et 2, 3.10.2003 (3 x 2 journées, français) AutoCAD 2002 - niveau 1 : 23, 24, 30.09.2003 et 1.10.2003 (2 x 2 journées) Introduction to the CERN Engineering Data Management System (EDMS): 23.09.2003 (1 day) The CERN Engineering Data Management System (EDMS) for Local Administrators: 24-25.09.2003 (2 days) AutoCAD 2002 - niveau 2 : 8 et 10.10.2003 (2 journées) CLEAN-2002: Working in a Cleanroom: 23.10.2003 (half day, p.m.) ** The number of places available may vary. Please check our Web site to find out the current availabili...

  7. Places available**

    CERN Multimedia

    2003-01-01

    Places are available in the following courses: Hands-on Introduction to Python Programming: 11-13.08.2003(3 days) Introduction to the CERN Engineering Data Management System (EDMS): 26.08.2003 (1 day) The CERN Engineering Data Management System (EDMS) for Engineers: 27.08.2003 (1 day) CLEAN-2002 : Travailler en salle blanche : 4.09.2003 (une demi-journée) AutoCAD 2002 - Level 1: 4, 5, 15, 16.09.2003 (2 x 2 days) AutoCAD Mechanical 6 PowerPack : 17, 18, 25, 26.09.2003 et 2, 3.10.2003 (3 x 2 journées, français) AutoCAD 2002 - niveau 1 : 23, 24, 30.09.2003 et 1.10.2003 (2 x 2 journées) Introduction to the CERN Engineering Data Management System (EDMS): 23.09.2003 (1 day) The CERN Engineering Data Management System (EDMS) for Local Administrators: 24-25.09.2003 (2 days) AutoCAD 2002 - niveau 2 : 8 et 10.10.2003 (2 journées) CLEAN-2002: Working in a Cleanroom: 23.10.2003 (half day, p.m.) ** The number of places available may vary. Please ch...

  8. Media places

    DEFF Research Database (Denmark)

    Linde, Per; Messeter, Jörn

    The impact that ubiquitous wireless network technologies and mobile phones have on our experience of the modern cityscape, has been a driving force in many research projects in recent years. The agendas differ in relation to perspectives, but it seems safe to claim that such technologies are no l......The impact that ubiquitous wireless network technologies and mobile phones have on our experience of the modern cityscape, has been a driving force in many research projects in recent years. The agendas differ in relation to perspectives, but it seems safe to claim that such technologies...... construction of place in the urban setting. The concept of Hertzian space, put forth by Anthony Dunne and others (Dunne, 1999) also carries a dimension of how spaces of wireless communication may be problematized, and how we can criticize cultural phenomena taken for granted through innovative technology. From...... this perspective wireless technology can also be a way of temporarily appropriating places within the city space for a variety of different groups, at times questioning hierarchical structures of ownership of public spaces. These spaces can be said to be hybrid spaces, bringing forth the fundamental question...

  9. Places available**

    CERN Multimedia

    2003-01-01

    If you wish to participate in one of the following courses, please discuss with your supervisor and apply electronically directly from the course description pages that can be found on the Web at: http://www.cern.ch/Training/ or fill in an "application for training" form available from your Divisional Secretariat or from your DTO (Divisional Training Officer). Applications will be accepted in the order of their receipt. TECHNICAL TRAINING Monique Duval Tel. 74924technical.training@cern.ch ** The number of places available may vary. Please check our Web site to find out the current availability. Places are available in the following courses: MATLAB Fundamentals and Programming Techniques (ML01) : 2 & 3.12.03 (2 days) Oracle 8i : SQL : 3 - 5.12.03 (3 days) The EDMS MTF in practice : 5.12.03 (afternoon, free of charge) Modeling Dynamic Systems with Simulink (SL01) : 8 & 9.12.03 (2 days) Signal Processing with MATLAB (SG01) : 11 & 12.12.03 (2 days) The JAVA Programming Language - l...

  10. Places available**

    CERN Multimedia

    2003-01-01

    If you wish to participate in one of the following courses, please discuss with your supervisor and apply electronically directly from the course description pages that can be found on the Web at: http://www.cern.ch/Training/ or fill in an "application for training" form available from your Divisional Secretariat or from your DTO (Divisional Training Officer). Applications will be accepted in the order of their receipt. TECHNICAL TRAINING Monique Duval tel. 74924 technical.training@cern.ch ** The number of places available may vary. Please check our Web site to find out the current availability. Places are available in the following courses: MATLAB Fundamentals and Programming Techniques (ML01) :2 & 3.12.03 (2 days) Oracle 8i : SQL : 3 - 5.12.03 (3 days) The EDMS MTF in practice : 5.12.03 (afternoon, free of charge) Modeling Dynamic Systems with Simulink (SL01) : 8 & 9.12.03 (2 days) Signal Processing with MATLAB (SG01) : 11 & ...

  11. Places available**

    CERN Multimedia

    2004-01-01

    If you wish to participate in one of the following courses, please discuss with your supervisor and apply electronically directly from the course description pages that can be found on the Web at: http://www.cern.ch/Training/ or fill in an "application for training" form available from your Divisional Secretariat or from your DTO (Divisional Training Officer). Applications will be accepted in the order of their receipt.TECHNICAL TRAINING Monique Duval tel. 74924 technical.training@cern.ch ** The number of places available may vary. Please check our Web site to find out the current availability. Places are available in the following courses: The JAVA Programming Language Level 1 : 9 & 10.1.2004 (2 days) The JAVA Programming Language Level 2 : 11 to 13.1.2004 (3 days) LabVIEW base 1 : 25 - 27.2.2004 (3 jours) CLEAN-2002 : Working in a Cleanroom : 10.3.2004 (afternoon - free of charge) C++ for Particle Physicists : 8 - 12.3.2004 ( 6 X 4-hour sessions) LabVIEW Basics 1 : 22 - 24.3.20...

  12. Places available**

    CERN Document Server

    2004-01-01

    If you wish to participate in one of the following courses, please discuss with your supervisor and apply electronically directly from the course description pages that can be found on the Web at: http://www.cern.ch/Training/ or fill in an "application for training" form available from your Divisional Secretariat or from your DTO (Divisional Training Officer). Applications will be accepted in the order of their receipt. TECHNICAL TRAINING Monique Duval tel. 74924 technical.training@cern.ch ** The number of places available may vary. Please check our Web site to find out the current availability. Places are available in the following courses: The JAVA Programming Language Level 1 :9 & 10.1.2004 (2 days) The JAVA Programming Language Level 2 : 11 to 13.1.2004 (3 days) Hands-on Introduction to Python Programming : 16 - 18.2.2004 (3 days - free of charge) CLEAN-2002 : Working in a Cleanroom : 10.3.2004 (afternoon - free of charge) C++ for Particle Physicists : 8 - 12.3.2004...

  13. Places available**

    CERN Document Server

    2003-01-01

    If you wish to participate in one of the following courses, please discuss with your supervisor and apply electronically directly from the course description pages that can be found on the Web at: http://www.cern.ch/Training/ or fill in an "application for training" form available from your Divisional Secretariat or from your DTO (Divisional Training Officer). Applications will be accepted in the order of their receipt. TECHNICAL TRAINING Monique Duval Tel. 74924 technical.training@cern.ch ** The number of places available may vary. Please check our Web site to find out the current availability. Places are available in the following courses: JAVA 2 Enterprise Edition - Part 1 : WEB Applications : 20 & 21.11.03(2 days) FrontPage 2000 - niveau 1 : 20 & 21.11.03 (2 jours) Oracle 8i : SQL : 3 - 5.12.03 (3 days) Oracle 8i : Programming with PL/SQL : 8 - 10.12.03 (3 days) The JAVA Programming Language - leve...

  14. Places available**

    CERN Multimedia

    2003-01-01

    If you wish to participate in one of the following courses, please discuss with your supervisor and apply electronically directly from the course description pages that can be found on the Web at: http://www.cern.ch/Training/ or fill in an "application for training" form available from your Divisional Secretariat or from your DTO (Divisional Training Officer). Applications will be accepted in the order of their receipt. TECHNICAL TRAINING Monique Duval tel. 74924 technical.training@cern.ch ** The number of places available may vary. Please check our Web site to find out the current availability. Places are available in the following courses: Project Planning with MS-Project : 15 & 22.1.2004 (2 days) Joint PVSS JCOP Framework Course : 2 sessions : 2 - 6.2.2004 and 16 - 20-2-2004 (5 days) Hands-on Introduction to Python Programming : 16 - 18.2.2004 (3 days - free of charge) C++ for Particle Physicists : 8 - 12.3.2004 ( 6 X 4-hour sessions)

  15. Places available **

    CERN Multimedia

    2003-01-01

    Des places sont disponibles dans les cours suivants : Places are available in the following courses : WorldFIP 2003 pour utilisateurs : 11-14.2.03 (4 jours) DISP-2003 ? Spring I Term : Introduction to Digital Signal Processing : 20, 27.2, 6, 13, 20, 27.3, 3.4.03 (7 X 2-hour lectures) AXEL-2003 - Introduction to Accelerators : 24-28.2.03 (10 X 1-hour lectures) AutoCAD 2002 - niveau 1 : 24, 25.2 & 3, 4.3.03 (4 jours) Introduction à Windows 2000 au CERN : 25.2.03 (1/2 journée) LabView base 2/LabView Basics 2 : 10 & 11.3.03 (2 jours/2 days) langue à définir/Language to be decided C++ for Particle Physicists : 10 ? 14.3.03 (6 X 3-hour lectures) Introduction to PVSS : 10.3.03 (half day, afternoon) Basic PVSS : 11 - 13.3.03 (3 days) LabView avancé /LabView Advanced : 12 - 14.3.03 (3 jours/3days) Langue à définir/language to be decided AutoCAD Mechanical 6 PowerPack (F) : 12, 13, 17, 18, 24 & 25.3.03 (6 jours) PVSS - JCOP Framework Tutorial : 14.3.03 (1 day) MAGNE-03 - Magnetism for Technical Ele...

  16. Places available **

    CERN Multimedia

    2003-01-01

    Des places sont disponibles dans les cours suivants : Places are available in the following courses : Introduction à Windows 2000 au CERN : 25.2.03 (1/2 journée) LabView base 2/LabView Basics 2 : 10 & 11.3.03 (2 jours/2 days) langue à définir/Language to be decided C++ for Particle Physicists : 10 - 14.3.03 (6 X 3-hour lectures) Introduction to PVSS : 10.3.03 (half day, afternoon) Basic PVSS : 11 - 13.3.03 (3 days) LabView avancé /LabView Advanced : 12 - 14.3.03 (3 jours/3days) Langue à définir/Language to be decided AutoCAD Mechanical 6 PowerPack (F) : 12, 13, 17, 18, 24 & 25.3.03 (6 jours) PVSS - JCOP Framework Tutorial : 14.3.03 (1 day) CLEAN-2002 : Working in a cleanroom : 2.4.03 (half-day, afternoon, free course, registration required) LabView base 1/LabView Basics 1 : 9 - 11.4.03 (3 jours/3 days) Langue à définir/Language to be decided DISP-2003 - Spring II Term : Advanced Digital Signal Processing : 30.4, 7, 14, 21.5.03 (4 X 2-hour lectures) AutoCAD 2002 - niveau 2 : 5 & 6.5.03 (...

  17. Places available **

    CERN Multimedia

    2003-01-01

    Des places sont disponibles dans les cours suivants : Places are available in the following courses : DISP-2003 - Spring I Term : Introduction to Digital Signal Processing : 20, 27.2, 6, 13, 20, 27.3, 3.4.03 (7 X 2-hour lectures) AXEL-2003 - Introduction to Accelerators : 24 - 28.2.03 (10 X 1-hour lectures) AutoCAD 2002 - niveau 1 : 24, 25.2 & 3, 4.3.03 (4 jours) Introduction à Windows 2000 au CERN : 25.2.03 (1/2 journée) LabView base 2/LabView Basics 2 : 10 & 11.3.03 (2 jours/2 days) langue à définir/Language to be decided C++ for Particle Physicists : 10 - 14.3.03 (6 X 3-hour lectures) Introduction to PVSS : 10.3.03 (half day, afternoon) Basic PVSS : 11 - 13.3.03 (3 days) LabView avancé /LabView Advanced : 12 - 14.3.03 (3 jours/3days) Langue à définir/language to be decided AutoCAD Mechanical 6 PowerPack (F) : 12, 13, 17, 18, 24 & 25.3.03 (6 jours) PVSS - JCOP Framework Tutorial : 14.3.03 (1 day) CLEAN-2002 : Working in a cleanroom : 2.4.03 (half-day, afternoon, free course, regis...

  18. Places available **

    CERN Multimedia

    2003-01-01

    Des places sont disponibles dans les cours suivants : Places are available in the following courses : C++ for Particle Physicists : 10 - 14.3.03 (6 X 3-hour lectures) Introduction to PVSS : 10.3.03 (half day, afternoon) Basic PVSS : 11 - 13.3.03 (3 days) PVSS - JCOP Framework Tutorial : 14.3.03 (1 day) CLEAN-2002 : Working in a cleanroom : 2.4.03 (half-day, afternoon, free course, registration required) LabView base 1/LabView Basics 1 : 9 - 11.4.03 (3 jours/3 days) Langue à définir/language to be decided DISP-2003 - Spring II Term : Advanced Digital Signal Processing : 30.4, 7, 14, 21.5.03 (4 X 2-hour lectures) AutoCAD 2002 - niveau 1 : 29, 30.4 et 7, 8.5.03 (4 jours) AutoCAD 2002 - niveau 2 : 5 & 6.5.03 (2 jours) AutoCAD Mechanical 6 PowerPack (F) : 12, 13, 20, 21, 27 & 28.5.03 (6 jours) Formation Siemens SIMATIC /Siemens SIMATIC Training : Introduction à STEP7 /Introduction to STEP7 : 11 & 12.3.03 / 3 & 4.6.03 (2 jours/2 days) Programmation STEP7/STEP7 Programming : 31.3 - 4.4.03 / 16...

  19. Places available**

    CERN Multimedia

    2003-01-01

    Places are available in the following courses: Conception de PCB rapides dans le flot Cadence : 11.6.03 (matin) EXCEL 2000 - level 1 : 12 & 13.6.03 (2 days) Introduction to PVSS : 16.6.03 (p.m.) Basic PVSS : 17 - 19.6.03 (3 days) Réalisation de PCB rapides dans le flot Cadence : 17.6.03 (matin) PVSS - JCOP Framework Tutorial : 20.6.03 (1 day) Programmation automate Schneider : Programmation automate Schneider TSX Premium - 2ème niveau : 24 - 27.6.03 (4 jours) - audience : toute personne qui veux maitriser la mise en uvre et la programmation des fonctions spécialisées d'un automate TSX Premium - objectifs : maitriser la mise en uvre et la programmation des fonctions spécialisées d'un automate TSX Premium Cours de sécurité : Etre TSO au CERN : Prochaines sessions : 24, 25 & 27.6.03 - 4, 5 & 7.11.03 (session de 3 jours) ** The number of places available may vary. Please check our Web site to find out the current availability. If you wish to participate in one of these courses, pl...

  20. Places available**

    CERN Multimedia

    2003-01-01

    If you wish to participate in one of these courses, please discuss with your supervisor and apply electronically directly from the course description pages that can be found on the Web at: http://www.cern.ch/Training/ or fill in an "application for training" form available from your Divisional Secretariat or from your DTO (Divisional Training Officer). Applications will be accepted in the order of their receipt. ** The number of places available may vary. Please check our Web site to find out the current availability. Places are available in the following courses : EXCEL 2000 - niveau 1 : 20 & 22.10.03 (2 jours) CLEAN-2002 : Working in a Cleanroom (free of charge) : 23.10.03 (half day) The EDMS-MTF in practice (free of charge) :  28 -  30.10.03 (6 half-day sessions) AutoCAD 2002 - Level 1 : 3, 4, 12, 13.11.03 (4 days) LabVIEW TestStand ver. 3 : 4 & 5.11.03 (2 days) Introduction to Pspice : 4.11.03 p.m. (half-day) Hands-on Introduction to Python Programm...

  1. PLACES AVAILABLE

    CERN Multimedia

    Enseignement Technique; Tél. 74924; Technical Training; Monique Duval; Tel. 74924

    2000-01-01

    Places available Places are available in the following courses:   LabView hands-on 13.11.00 4 hours LabView Basics 1 14 - 16.11.00 3 days Nouveautés de WORD 19 et 20.10.00 2 jours ACCESS 1er niveau 30 - 31.10.00 2 jours Advanced aspects of the C language 2 - 3.11.00 2 days Introduction to Oracle SQL and PL/SQL 13 - 17.11.00 5 days C++ for Particle Physicists 20 - 24.11.00 6 lectures Develop PL/SQL Program Units 20 - 22.11.00 3 days Oracle Application Server Develop Web-Based Applications with PL/SQL 27 - 28.11.00 2 days Programmation TSX Premium 1 28.11 - 1.12.00 4 jours Programmation TSX Premium 2 12 - 15.12.00 4 jours If you wish to participate in one of these courses, please discuss with your supervisor and apply electronically directly from the course description pages that can be found on the Web at : http://www.cern.ch/Training/ or fill in an “application for training” form available from your Divisional Secretariat or from your DTO (Divisional Training Offi...

  2. Thermoplasmonic Ignition of Metal Nanoparticles.

    Science.gov (United States)

    Mutlu, Mehmet; Kang, Ju-Hyung; Raza, Søren; Schoen, David; Zheng, Xiaolin; Kik, Pieter G; Brongersma, Mark L

    2018-03-14

    Explosives, propellants, and pyrotechnics are energetic materials that can store and quickly release tremendous amounts of chemical energy. Aluminum (Al) is a particularly important fuel in many applications because of its high energy density, which can be released in a highly exothermic oxidation process. The diffusive oxidation mechanism (DOM) and melt-dispersion mechanism (MDM) explain the ways powders of Al nanoparticles (NPs) can burn, but little is known about the possible use of plasmonic resonances in NPs to manipulate photoignition. This is complicated by the inhomogeneous nature of powders and very fast heating and burning rates. Here, we generate Al NPs with well-defined sizes, shapes, and spacings by electron beam lithography and demonstrate that their plasmonic resonances can be exploited to heat and ignite them with a laser. By combining simulations with thermal-emission, electron-, and optical-microscopy studies, we reveal how an improved control over NP ignition can be attained.

  3. The Ignition Physics Study Group

    International Nuclear Information System (INIS)

    Sheffield, J.

    1987-01-01

    In the US magnetic fusion program there have been relatively few standing committees of experts, with the mandate to review a particular sub-area on a continuing basis. Generally, ad hoc committees of experts have been assembled to advise on a particular issue. There has been a lack of broad, systematic and continuing review and analysis, combining the wisdom of experts in the field, in support of decision making. The Ignition Physics Study Group (IPSG) provides one forum for the systematic discussion of fusion science, complementing the other exchanges of information, and providing a most important continuity in this critical area. In a similar manner to the European program, this continuity of discussion and the focus provided by a national effort, Compact Ignition Tokamak (CIT), and international effort, Engineering Test Reactor (ETR), are helping to lower those barriers which previously were an impediment to rational debate

  4. Place identity and place scale: the impact of place salience.

    OpenAIRE

    Bernardo, Fátima; Palma-Oliveira, José-Manuel

    2013-01-01

    Research about place, place identity and attachment supports the idea that bonds with places may differ depending on the place scale. Based on the view that identity is context-dependent, this paper brings to the table the impact of manipulating the salience of place on the intensity of place identity and place attachment reported. A study was designed to examine place identity and place attachment in two groups of residents (permanent and temporary) at three different scales (nei...

  5. Low current approach to ignition

    International Nuclear Information System (INIS)

    Cenacchi, G.; Sugiyama, L.; Airoldi, A.; Coppi, B.

    1996-01-01

    The open-quotes standardclose quotes path to achieve ignition conditions so far has been that of producing plasmas with the maximum current and poloidal field that axe compatible with the applied toroidal field and the geometry of the adopted configuration (the low q a approach.) The other approach is that motivated by recent experiments with reversed shear configurations, with relatively low currents and high fields corresponding to high values of q a (e-g., q a ≅ 6). While the first approach can be pursued with ohmic heating alone, the second one necessarily involves an auxiliary heating system. One of the advantages of this approach is that the onset of large scale internal modes can be avoided as q(ψ) is kept above 1 over the entire plasma column. Since quite peaked density profiles are produced in the regimes where enhanced confinement is observed, the α-particle power levels for which ignition can be reached and therefore the thermal wall loading on the first wall, can be reduced relatively to the standard, low q a , approach. The possibility is considered that ignition is reached in the reversed shear, high q a , regime and that this is followed by a transition to non-reversed profiles, or even the low q a regime, assuming that the excitation of modes involving magnetic reconnection will not undermine the needed degree of confinement. These results have been demonstrated by numerical transport simulation for the Ignitor-Ult machine, but are applicable to all high field ignition experiments

  6. PLACES AVAILABLE

    CERN Multimedia

    Technical Training; Tel. 74924

    2001-01-01

    Places are available in the following courses: Introduction to Databases :  3 - 4.7.01 (2 days) The JAVA programming language Level 2 : 4 - 6.7.01 (3 days) Enterprise JavaBeans :  9 - 11.7.01 (3 days) Design Patterns :  10 - 12.7.01 (3 days) C++ for Particle Physicists :  23 - 27.7.01 (6 3-hour lectures) If you wish to participate in one of these courses, please discuss with your supervisor and apply electronically directly from the course description pages that can be found on the Web at : http://www.cern.ch/Training/ or fill in an 'application for training' form available from your Divisional Secretariat or from your DTO (Divisional Training Officer). Applications will be accepted in the order of their receipt.

  7. PLACES AVAILABLE

    CERN Multimedia

    Technical Training; Tel. 74924

    2001-01-01

    Places are available in the following courses: Introduction to Perl 5 : 2 - 3.7.01 (2 days) Introduction to Databases :  3 - 4.7.01 (2 days) JAVA programming language Level 2 : 4 - 6.7.01 (3 days) Enterprise JavaBeans :  9 - 11.7.01 (3 days) Design Patterns :  10 - 12.7.01 (3 days) C++ for Particle Physicists :  23 - 27.7.01 (6 3-hour lectures) If you wish to participate in one of these courses, please discuss with your supervisor and apply electronically directly from the course description pages that can be found on the Web at : http://www.cern.ch/Training/ or fill in an 'application for training' form available from your Divisional Secretariat or from your DTO (Divisional Training Officer). Applications will be accepted in the order of their receipt.

  8. PLACES AVAILABLE

    CERN Multimedia

    Monique Duval

    2002-01-01

    Places are available in the following courses: CLEAN-2002 : Travailler en salle blanche (cours gratuit) : 13.08.2002 (matin) Introduction to the CERN Enginnering Data Management System :  27.8.02  (1 day) The CERN Engineering Data Management System for Advanced Users :  28.8.02  (1 day) If you wish to participate in one of these courses, please discuss with your supervisor and apply electronically directly from the course description pages that can be found on the Web at : Technical Training or fill in an 'application for training' form available from your Divisional Secretariat or from your DTO (Divisional Training Officer). Applications will be accepted in the order of their receipt. Technical Training Monique Duval Tel.74924 monique.duval@cern.ch    

  9. PLACES AVAILABLE

    CERN Multimedia

    Monique Duval

    2002-01-01

    Places are available in the following courses: C++ Programming Level 2 - Traps & Pitfalls:  16 - 19.7.02 (4 days) Frontpage 2000 - level 1 :  22 - 23.7.02  (2 days) Introduction à Windows 2000 au CERN : 24.7.02 (après-midi) CLEAN-2002 : Travailler en salle blanche (cours gratuit) : 13.08.2002 (matin) If you wish to participate in one of these courses, please discuss with your supervisor and apply electronically directly from the course description pages that can be found on the Web at : Technical Training or fill in an 'application for training' form available from your Divisional Secretariat or from your DTO (Divisional Training Officer). Applications will be accepted in the order of their receipt. Technical Training Monique Duval Tel.74924 monique.duval@cern.ch

  10. Placing knowledge

    DEFF Research Database (Denmark)

    Adriansen, Hanne Kirstine; Valentin, Karen; Nielsen, Gritt B.

    ; on the other hand, the rationale for strengthening mobility through internationalisation is based on an imagination of the potentials of particular locations (academic institutions). Intrigued by this tension between universality and particularity in academic knowledge production, this paper presents...... preliminary findings from a project that study internationalisation of higher education as an agent in the interrelated processes of place-making and knowledge-making. The project is based on three case-studies. In this paper, focus is on PhD students’ change of research environment. This is used as a case......Internationalisation of higher education is premised by a seeming paradox: On the one hand, academic knowledge strives to be universal in the sense that it claims to produce generalizable, valid and reliable knowledge that can be used, critiqued, and redeveloped by academics from all over the world...

  11. PLACES AVAILABLE

    CERN Multimedia

    Monique Duval

    2002-01-01

    Places are available in the following courses: December 2002   PCAD Schémas - Débutants :  5 & 6.12.02  (2 jours) PCAD PCB - Débutants :  9 - 11.12.02  (3 jours) FrontPage 2000 - level 1:  9 & 10.12.02  (2 days) Introduction à la CAO Cadence (cours gratuit) :  10 & 11.12.02  (2 jours) If you wish to participate in one of these courses, please discuss with your supervisor and apply electronically directly from the course description pages that can be found on the Web at : Technical Training or fill in an 'application for training' form available from your Divisional Secretariat or from your DTO (Divisional Training Officer). Applications will be accepted in the order of their receipt. Technical Training Monique Duval Tel.74924 monique.duval@cern.ch

  12. Effects of enhanced elongation and paramagnetism on the parameter space of the ignition spherical torus

    International Nuclear Information System (INIS)

    Strickler, D.J.; Peng, Y-K.M.; Borowski, S.K.; Selcow, E.C.; Miller, J.B.

    1985-01-01

    The Ignition Spherical Torus (IST) is a small aspect ratio device retaining only indispensable components along the major axis of a tokamak plasma, such as a cooled, normal conductor producing a toroidal magnetic field. The IST is expected to be a cost-effective approach to ignition by taking advantage of low field, large natural plasma elongation, high plasma current, high beta, and tokamak confinement. These result in compact, high-performance devices with relatively simple magnetic systems as compared with ignition tokamaks of larger aspect ratio. The plasma enhancement of the toroidal field on axis, or plasma paramagnetism, is significant in the IST. The use of this plasma-enhanced field in conventional tokamak beta and density limits leads to increased plasma pressure and performance and therefore smaller device size for a given ignition margin

  13. A sustained-arc ignition system for internal combustion engines

    Science.gov (United States)

    Birchenough, A. G.

    1977-01-01

    A sustained-arc ignition system was developed for internal combustion engines. It produces a very-long-duration ignition pulse with an energy in the order of 100 millijoules. The ignition pulse waveform can be controlled to predetermined actual ignition requirements. The design of the sustained-arc ignition system is presented in the report.

  14. Understanding Biomass Ignition in Power Plant Mills

    DEFF Research Database (Denmark)

    Schwarzer, Lars; Jensen, Peter Arendt; Glarborg, Peter

    2017-01-01

    . This is not very well explained by apply-ing conventional thermal ignition theory. An experimental study at lab scale, using pinewood as an example fuel, was conducted to examine self-heating and self-ignition. Supplemental experiments were performed with bituminous coal. Instead of characterizing ignition......Converting existing coal fired power plants to biomass is a readily implemented strategy to increase the share of renewable energy. However, changing from one fuel to another is not straightforward: Experience shows that wood pellets ignite more readily than coal in power plant mills or storages...... temperature in terms of sample volume, mass-scaling seems more physically correct for the self-ignition of solids. Findings also suggest that the transition between self-heating and self-ignition is controlled both by the availability of reactive material and temperature. Comparison of experiments at 20...

  15. Laser Ignition Microthruster Experiments on KKS-1

    Science.gov (United States)

    Nakano, Masakatsu; Koizumi, Hiroyuki; Watanabe, Masashi; Arakawa, Yoshihiro

    A laser ignition microthruster has been developed for microsatellites. Thruster performances such as impulse and ignition probability were measured, using boron potassium nitrate (B/KNO3) solid propellant ignited by a 1 W CW laser diode. The measured impulses were 60 mNs ± 15 mNs with almost 100 % ignition probability. The effect of the mixture ratios of B/KNO3 on thruster performance was also investigated, and it was shown that mixture ratios between B/KNO3/binder = 28/70/2 and 38/60/2 exhibited both high ignition probability and high impulse. Laser ignition thrusters designed and fabricated based on these data became the first non-conventional microthrusters on the Kouku Kousen Satellite No. 1 (KKS-1) microsatellite that was launched by a H2A rocket as one of six piggyback satellites in January 2009.

  16. Electronic ignition system for internal combustion engines

    Energy Technology Data Exchange (ETDEWEB)

    Crowder, L W

    1980-11-20

    Mechanical ignition adjustment devices are sensitive to many effects, for example breakage, faults due to manufacturing tolerances, play in the linkage and the effect of a dirty or corrosive environment. It is therefore the purpose of the invention to provide an electronic ignition system which avoids the disadvantages of a mechanical system. The invention provides adjustment of the ignition point, which gives advance of the ignition timing with increasing speed. An output signal is formed, which supersedes the signal supplied by the electronic control system, so that the ignition is advanced. This also occurs with a larger crankshaft angle before top dead centre of the engine. The electronic control system combines with a source of AC time signals which has a generator as electrical transmitter and a DC battery and ignition coil. The rotor of the electrical generator is driven synchronised with the engine. Structural and functional details of the transistor control circuits are given in 5 patent claims.

  17. Places available **

    CERN Multimedia

    2003-01-01

    Places are available in the following courses: PIPES-2003 - Pratique du Sertissage de tubes métalliques et multicouches : 26.8.03 (stage pratique) The CERN Engineering Data Management System (EDMS) for Engineers : 27.8.03 (1 day, free of charge) CLEAN-2002 : Travailler en salle blanche : 4.9.03 (une demi-journée, séminaire gratuit) The CERN Engineering Data Management System (EDMS) for Local Administrators : 24 & 25.9.03 (2 days, free of charge) Siemens SIMATIC Training : Programmation STEP7 - niveau 1 : 29 - 2.10.03 (4 jours) - ouverture des inscriptions fin août Programmation STEP7 - niveau 2 : 13 - 17.10.03 (5 jours) - ouverture des inscriptions fin août Réseau Simatic Net : 22 & 23.10.03 (2 jours) - ouverture des inscriptions fin août CLEAN-2002 : Working in a Cleanroom : 23.20.03 (half day, free of charge) These courses will be given in French or Englis...

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    2003-01-01

    Places are available in the following courses : FrontPage 2000 - niveau 1: 20 & 21.5.03 (2 jours) PIPES-2003 : Pratique du sertissage de tubes métalliques et multicouches: 21.5.03 (1 jour) Introduction à la CAO Cadence: de la saisie de schéma Concept-HDL au PCB : 20 & 22.5.03 (2 jours) AutoCAD Mechanical 6 PowerPack (E): 5, 6, 12, 13, 26, 27.6.03 (6 days) EXCEL 2000 - niveau 1: 10 & 11.6.03 (2 jours) Conception de PCB rapides dans le flot Cadence: 11.6.03 (matin) EXCEL 2000 - level 1: 12 & 13.6.03 (2 days) Introduction to PVSS: 16.6.03 (half-day, pm) Basic PVSS: 17 - 19.6.03 (3 days) Réalisation de PCB rapides dans le flot Cadence: 17.6.03 (matin) LabView DSC (language to be defined): 19 & 20.6.03 PVSS - JCOP Framework Tutorial: 20.6.03 (1 day) EXCEL 2000 - niveau 2: 24 & 25.6.03 (2 jours) Siemens SIMATIC Training: Introduction to STEP7: 3 & 4.6.03 (2 days) STEP7 Programming: 16 - 20.6.03 (5 days) Simatic Net Network: 26 & 27.6.03 (2 days) These courses will be given...

  19. PLACES AVAILABLE

    CERN Multimedia

    Monique Duval

    2002-01-01

    Places are available in the following courses: LabView Hands-on (bilingue/bilingual - gratuit/free of charge) : 13.9.02 (a.m.) LabView DAQ Hands-on (bilingue/bilingual - gratuit/free of charge) : 13.9.02 (p.m.) AutoCAD 2002 - niveau 1 : 19, 20, 26, 27.9.02 (4 jours) LabView Base 1 : 23 - 25.9.02 (3 jours) LabView DAQ (E) : 26 - 27.9.02 (2 days) AutoCAD Mechanical 6 PowerPack (F) : 30.9, 1, 2, 9, 10, 11.10.02 (6 jours) CLEAN-2002 : Working in a Cleanroom (free of charge) : 10.10.02 (half-day, p.m.) AutoCAD 2002 - niveau 2 : 14 - 15.10.02 (2 jours) AutoCAD 2002 - Level 1 : 17, 18, 24, 25.10.02 (4 days) If you wish to participate in one of these courses, please discuss with your supervisor and apply electronically directly from the course description pages that can be found on the Web at : Technical Training or fill in an 'application for training' form available from your Divisional Secretariat or from your DTO (Divisional Training Of...

  20. PLACES AVAILABLE

    CERN Multimedia

    Monique Duval

    2002-01-01

    Places are available in the following courses: Introduction to Oracle 8i : SQL and PL/SQL:  7 - 11.10.02  (5 days) CLEAN-2002 : Working in a Cleanroom (free of charge):  10.10.02  (half-day, p.m.) AutoCAD 2002 - niveau 2 :  14 - 15.10.02  (2 jours) Introduction à DesignSpace :  16.10.02  (1 journée) Introduction to DesignSpace:  17.10.02  (1 day) AutoCAD 2002 - Level 1:  17, 18, 24, 25.10.02  (4 days) AutoCAD Mechanical 6 PowerPack (F) :  21, 22, 23.10 et 4, 5, 6.11.02  (6 jours) Introduction à ANSYS/Introduction to ANSYS (langue à définir suivant demande/ Language to be chosen according to demand):  21 - 25.10.02  (5 jours/days) HREF-2002: Helium Refrigeration Techniques (English-French, bilingual) :  21 - 25.10.2002  (7 half days) HREF-2002: Techniques de la Réfri...

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    CERN Document Server

    2003-01-01

    Places are available in the following courses : The CERN EDMS for Local Administrators : 24 & 25.9.03 (2 days, free of charge) HeREF-2003 : Techniques de la réfrigération Hélium (cours en français avec support en anglais) : 6 - 10.10.2003 (7 demi-journées) The Java Programming Language Level 1 : 6 - 7.10.2003 (2 days) Java 2 Enterprise Edition - Part 2 : Enterprise JavaBeans : 8 - 10.10.2003 (3 days) FileMaker - niveau 1 : 9 & 10.10.03 (2 jours) EXCEL 2000 - niveau 1 : 20 & 22.10.03 (2 jours) AutoCAD 2002 - niveau 1 : 20, 21, 27, 28.10.03 (4 jours) CLEAN-2002 : Working in a Cleanroom : 23.10.03 (half day, free of charge) AutoCAD 2002 - Level 1 : 3, 4, 12, 13.11.03 (4 days) AutoCAD 2002 - niveau 2 : 10 & 11.11.03 (2 jours) ACCESS 2000 - niveau 1 : 13 & 14.11.03 (2 jours) AutoCAD Mechanical 6 PowerPack (E) : 17, 18, 24, 25.11 & 1, 2.12.03 (6...

  2. PLACES AVAILABLE

    CERN Multimedia

    Monique Duval

    2002-01-01

    Places are available in the following courses: Introduction à DesignSpace :  16.10.02  (1 journée) AutoCAD Mechanical 6 PowerPack (F) :  21, 22, 23.10 et 4, 5, 6.11.02  (6 jours) Introduction à ANSYS 21 - 25.10.02  (5 jours/days) HREF-2002: Helium Refrigeration Techniques (English-French, bilingual) :  21 - 25.10.2002  (7 half days) LabVIEW Basics 1 (English):  21 - 23.10.02  (3 days) LabVIEW Basics 2 (English):  24 & 25.10.02  (2 days) Oracle 8i : Access the Database with Java:  7 & 8.11.02  (2 days) AutoCAD 2002 - niveau 2 :  7 & 8.11.02  (2 jours) AutoCAD 2002 - Level 1:  14, 15, 21, 22.11.02  (4 days) LabVIEW - Advanced (English) :  18 - 20.11.2002  (3 days) AutoCAD 2002 - niveau 1 :  19, 20, 25, 26.11.02 (4 jours) Oracle iDS Designer: First Class:&...

  3. Places available**

    CERN Document Server

    2003-01-01

    Places are available in the following courses: CLEAN-2002 : Travailler en salle blanche (séminaire gratuit) : 4.9.03 (une demi-journée) The CERN EDMS for Local Administrators (free of charge) : 24 & 25.9.03 (2 days) HeREF-2003 : Techniques de la réfrigération Hélium (cours en français avec support en anglais) : 6 - 10.10.2003 (7 demi-journées) The Java Programming Language Level 1 : 6 - 7.10.2003 (2 days) Java 2 Enterprise Edition - Part 2 : Enterprise JavaBeans : 8 - 10.10.2003 (3 days) FileMaker - niveau 1 : 9 & 10.10.03 (2 jours) EXCEL 2000 - niveau 1 : 20 & 22.10.03 (2 jours) AutoCAD 2002 - niveau 1 : 20, 21, 27, 28.10.03 (4 jours) CLEAN-2002 : Working in a Cleanroom (free of charge) : 23.10.03 (half day) AutoCAD Mechanical 6 PowerPack (E) : 23, 24, 30, 31.10 & 12, 13.11.03 (6 days) AutoCAD 2002 - niveau 2 : 10 & 11.11.03 (2 jours)...

  4. Places available**

    CERN Multimedia

    2003-01-01

    Places are available in the following courses: The CERN EDMS for Local Administrators : 24 & 25.9.03 (2 days, free of charge) HeREF-2003 : Techniques de la réfrigération Hélium cours en français avec support en anglais) : 6 - 10.10.2003 (7 demi-journées) The Java Programming Language Level 1 : 6 - 7.10.2003 (2 days) Java 2 Enterprise Edition - Part 2 : Enterprise JavaBeans : 8 - 10.10.2003 (3 days) FileMaker - niveau 1 : 9 & 10.10.03 (2 jours) EXCEL 2000 - niveau 1 : 20 & 22.10.03 (2 jours) AutoCAD 2002 - niveau 1 : 20, 21, 27, 28.10.03 (4 jours) CLEAN-2002 : Working in a Cleanroom : 23.10.03 (half day, free of charge) AutoCAD 2002 - Level 1 : 3, 4, 12, 13.11.03 (4 days) AutoCAD 2002 - niveau 2 : 10 & 11.11.03 (2 jours) ACCESS 2000 - niveau 1 : 13 & 14.11.03 (2 jours) AutoCAD Mechanical 6 PowerPack (E) : 17, 18, 24, 25.11 & 1, 2.12.03 (6 days) FrontPage 2000 - niveau 1 : 20 & 21.11.03 (2 jours) MAGNE-03 : Magnétisme pour l'électrotechnique : 25 - 27.11.03 (3 jours) ...

  5. PLACES AVAILABLE

    CERN Multimedia

    Monique Duval

    2002-01-01

    Places are available in the following courses: LabView hands-on (bilingue/bilingual): 5.11.02 (matin/morning) LabView DAQ hands-on (bilingue/bilingual):  5.11.02  (après-midi afternoon) Introduction au PC et Windows 2000 au CERN:  6 & 7.11.02  (2 jours) Oracle 8i : Access the Database with Java:  7 & 8.11.02  (2 days) AutoCAD 2002 - niveau 2:  7 & 8.11.02  (2 jours) Introduction to PVSS (free of charge):  11.11.2002 pm  (1/2 day) Basic PVSS:  12 - 14.11.02  (3 days) EXCEL 2000 - niveau 1:  12 & 13.11.02  (2 jours) CLEAN-2002: Working in a Cleanroom (English, free of charge):  13.11.2002  (afternoon) LabView Base 1 :  13 - 15.11.02  (3 jours) AutoCAD 2002 - Level 1:  14, 15, 21, 22.11.2002  (4 days) LabVIEW - Advanced:  18 - 20.11.02  (3 days) Auto...

  6. Places available**

    CERN Multimedia

    2003-01-01

    Places are available in the following courses: PIPES-2003 - Pratique du sertissage de tubes métalliques et multicouches :26.8.03(stage pratique) The CERN EDMS for Engineers (free of charge) : 27.8.03 (1 day) CLEAN-2002 : Travailler en salle blanche (séminaire gratuit) : 4.9.03(une demi-journée) The CERN EDMS for Local Administrators (free of charge) : 24 & 25.9.03 (2 days) HeREF-2003 : Techniques de la réfrigération Hélium (cours en français avec support en anglais) : 6 - 10.10.2003 (7 demi-journées) The Java Programming Language Level 1 : 6 - 7.10.2003 (2 days) Java 2 Enterprise Edition - Part 2 : Enterprise JavaBeans : 8 - 10.10.2003 (3 days) FileMaker - niveau 1 : 9 & 10.10.03 (2 jours) EXCEL 2000 - niveau 1 : 20 & 22.10.03 (2 jours) AutoCAD 2002 - niveau 1 : 20, 21, 27, 28.10.03 (4 jours) CLEAN-2002 : Working in a Cleanroom (free of charge) : 23.10.03 (half day) AutoCAD Mechanical 6 PowerPack (E) : 23, 24, 30, 31.10 & 12, 13.11.03 (6 days) AutoCAD 2002 - niveau 2...

  7. Places available**

    CERN Multimedia

    2003-01-01

    Places are available in the following courses: The CERN EDMS for Local Administrators (free of charge) : 24 & 25.9.03 (2 days) HeREF-2003 : Techniques de la réfrigération Hélium (cours en français avec support en anglais) : 6 - 10.10.2003 (7 demi-journées) The Java Programming Language Level 1 : 6 - 7.10.2003 (2 days) Java 2 Enterprise Edition - Part 2 : Enterprise JavaBeans : 8 - 10.10.2003 (3 days) FileMaker - niveau 1 : 9 & 10.10.03 (2 jours) EXCEL 2000 - niveau 1 : 20 & 22.10.03 (2 jours) AutoCAD 2002 - niveau 1 : 20, 21, 27, 28.10.03 (4 jours) CLEAN-2002 : Working in a Cleanroom (free of charge) : 23.10.03 (half day) AutoCAD Mechanical 6 PowerPack (E) : 23, 24, 30, 31.10 & 12, 13.11.03 (6 days) AutoCAD 2002 - niveau 2 : 10 & 11.11.03 (2 jours) ACCESS 2000 - niveau 1 : 13 & 14.11.03 (2 jours) FrontPage 2000 - niveau 1 : 20...

  8. PLACES AVAILABLE

    CERN Multimedia

    Monique Duval

    2002-01-01

    Places are available in the following courses: October 2002   Introduction to the CERN Engineering Data Management System (free of charge):  29.10.2002  (1 day) The CERN EDMS for Advanced users (free of charge):  30.10.2002  (1 day) November 2002   LabView hands-on (bilingue/bilingual): 5.11.02 (matin/morning) LabView DAQ hands-on (bilingue/bilingual):  5.11.02  (après-midi afternoon) Introduction au PC et Windows 2000 au CERN :  6 & 7.11.02  (2 jours) Oracle 8i : Access the Database with Java:  7 & 8.11.02  (2 days) AutoCAD 2002 - niveau 2 :  7 & 8.11.02  (2 jours) Introduction to PVSS (free of charge):  11.11.2002 pm  (1/2 day) Basic PVSS:  12 - 14.11.02  (3 days) EXCEL 2000 - niveau 1 :  12 & 13.11.02  (2 jours) CLEAN-2002: Working in a Cleanroom (English, free ...

  9. PLACES AVAILABLE

    CERN Multimedia

    Monique Duval

    2002-01-01

    Places are available in the following courses: Introduction to Oracle 8i : SQL and PL/SQL:  7 - 11.10.02  (5 days) CLEAN-2002 : Working in a Cleanroom (free of charge):  10.10.02  (half-day, p.m.) LabView Hands-on (bilingue/bilingual) : 10.10.02 (matin/morning) LabView DAQ Hands-on (bilingue/bilingual)  10.10.02 (après-midi /afternoon) Introduction à DesignSpace :  16.10.02  (1 journée) Introduction to DesignSpace:  17.10.02  (1 day) AutoCAD Mechanical 6 PowerPack (F) :  21, 22, 23.10 et 4, 5, 6.11.02  (6 jours) Introduction à ANSYS/Introduction to ANSYS (langue à définir suivant demande/ Language to be chosen according to demand):  21 - 25.10.02  (5 jours/days) HREF-2002: Helium Refrigeration Techniques (English-French, bilingual) :  21 - 25.10.2002  (7 half days) HREF-2002: Techniques de la...

  10. PLACES AVAILABLE

    CERN Multimedia

    Technical Training; Tel 74924

    2002-01-01

    Places are available in the following courses: LabView hands-on : 21.01.02 (1/2 journée) LabView DAQ hands-on : 21.01.02 (1/2 journée) FileMaker Pro : 22 - 25.1.02 (4 jours) MS-Project 2000 : 24 & 25.01.02 (2 jours) Introduction au PC et à Windows 2000 au CERN : 29 - 30.1.02 (2 jours) LabView Base 1 : 4 - 6.2.02 (3 jours) LabView DAQ (E) : 7 & 8.02.02 (2 days) Hands-on Object-Oriented Design & Programming with Java : 11 - 13.02.02 (3 days) C++ for Particle Physicists : 11 - 15.3.2002 (6 * 3 hour lectures) Cours sur la migration AutoCAD : AutoCAD : Mise à jour AutoCAD r-14 vers 2002 (2 jours) AutoCAD Mechanical PowerPack 6 basé sur AutoCAD 2002 (5 jours) If you wish to participate in one of these courses, please discuss with your supervisor and apply electronically directly from the course description pages that can be found on the Web at : Technical Training or fill in an 'application for training' form available from your Divisional Secretariat or from your DTO ...

  11. PLACES AVAILABLE

    CERN Multimedia

    Enseignement Technique; Tél. 74924; Technical Training; Monique Duval; Tel. 74924

    2000-01-01

    Places are available in the following courses : Premiers pas avec votre PC 12 - 15.9.00 (4 demi-journées) WORD 20, 21 et 26, 27.9.2000 (4 jours) JAVA programming level 1 25 - 26.9.2000 (2 days) Gaz inflammables 1 26.9.2000 (1 journée) Advanced aspects of PERL 5 6.10.2000 (1 day) Initiation au WWW 10 - 12.10.00 (3 demi-journées) WORD : importer et manipuler des images 16.10.2000 (1 journée) FileMaker 17, 18 et 24, 25.10.00 (4 jours) Nouveautés de WORD 19 et 20.10.2000 (2 jours) ACCESS 1er niveau 30 - 31.10.00 (2 jours)Introduction à PowerPoint 6.11.00 (1 journée)Nouveautés d’EXCEL 7.11.2000(4 demi-journées)Excel 13, 14 et 20, 21.11.00 (4 jours) LabView hands-on 13.11.2000(4 hours)LabView Basics 1 14 - 16.11.2000 (3 days) MS-Project 1er niveau 14-17.11.00 (4 demi-journées) If you wish to participate in one of these courses, please discuss with your supervisor and apply elec...

  12. PLACES AVAILABLE

    CERN Multimedia

    TECHNICAL TRAINING; Tel. 74460

    2001-01-01

    Places are available in the following courses: MS-Project 1er niveau : 20 - 23.2.01 (4 matins) Architecture d'automatisme : 20 - 21.2.01 (2 jours) Introduction à PowerPoint : 26.2.01 (1 journée) Programmation TSX Premium 1 (Schneider) : 26.2 - 2.3.01 (5 jours) Premiers pas avec votre PC : 27.2 - 2.3.01 (4 matins) C++ for Particle Physicists : 5 - 9.3.01 (6*3 hour lectures) EXCEL : 6, 7 et 13, 14.3.01 (4 jours) The JAVA programming language level 2 :  12 - 14.3.01 (3 days) Nouveautés de FileMaker :  20 - 23.03.01 (4 matins) If you wish to participate in one of these courses, please discuss with your supervisor and apply electronically directly from the course description pages that can be found on the Web at : http://www.cern.ch/Training/ or fill in an 'application for training' form available from your Divisional Secretariat or from your DTO (Divisional Training Officer). Applications will be accepted in the order of their receipt.

  13. PLACES AVAILABLE

    CERN Multimedia

    Technical Training; Tel. 74924

    2002-01-01

    Places are available in the following courses: LabView hands-on : 21.01.02 (1/2 journée) LabView DAQ hands-on : 21.01.02 (1/2 journée) FileMaker Pro : 22 - 25.1.02 (4 jours) MS-Project 2000 : 22, 24 & 25.01.02 (3 jours) Introduction au PC et à Windows 2000 au CERN : 29 - 30.1.02 (2 jours) LabView Base 1 : 4 - 6.2.02 (3 jours) LabView DAQ  (E) :  7 & 8.02.02 (2 days) Hands-on Object-Oriented Design & Programming with Java :  11 - 13.02.02 (3 days) PVSS basics :  11 - 15.2.02 (5 days) Introduction à Windows 2000 : 18.2.02 (1 demi-journée) Introduction to the CERN Engineering Data Management System :  20.2.02 (1 day) The CERN Engineering Data Management System for Advanced users :  21.2.02  (1 day) C++ for Particle Physicists :  11 - 15.3.2002  (6 * 3 hour lectures) Cours sur la migration AutoCAD : AutoCAD : Mise à...

  14. PLACES AVAILABLE

    CERN Multimedia

    Technical Training; Tel. 74924

    2001-01-01

    Places are available in the following courses: LabVIEW - Basics 1 :  10 - 12.12.01 (3 days) Introduction to XML :  12 & 13.12.01 (2 days) Introduction au PC et Windows 2000 : 12 & 14.12.01 (2 jours) LabVIEW - Basics 2 :  13 - 14.12.01 (2 days) Habilitation électrique : superviseurs : 17.12.2001 (1/2 journée) MS-Project 2000 : 10 & 11.01.02 (2 jours) EXCEL 2000 - niveau 2 : 15 - 16.1.02 (2 jours) Sécurité dans les installations cryogéniques: 15-17.1.2002 (2 demi-journées) C++ Programming Level 2 - Traps and Pitfalls :  15 - 18.1.2002  (4 days) ELEC-2002 Winter Term: Readout and system electronics for Physics  15.1.2002 - 7.2.2002 (8 half- days) Nouveautés de WORD 2000 : 18.1.02 (1/2 journée) LabView hands-on : 21.01.02 (1/2 journée) LabView DAQ hands-on : 21.01.02 (1/2 journée) FileMaker Pro : 22 -...

  15. PLACES AVAILABLE

    CERN Multimedia

    Enseignement Technique; Tel. 74924

    2001-01-01

    Places are available in the following courses: MS-Project 2000 : 10 & 11.01.02 (2 jours) EXCEL 2000 - niveau 2 : 15 - 16.1.02 (2 jours) Sécurité dans les installations cryogéniques: 15-17.1.2002 (2 demi-journées) C++ Programming Level 2 - Traps and Pitfalls :  15 - 18.1.2002  (4 days) ELEC-2002 Winter Term: Readout and system electronics for Physics  15.1.2002 - 7.2.2002 (8 half- days) Nouveautés de WORD 2000 : 18.1.02 (1/2 journée) LabView hands-on : 21.01.02 (1/2 journée) LabView DAQ hands-on : 21.01.02 (1/2 journée) FileMaker Pro : 22 - 25.1.02 (4 jours) MS-Project 2000 : 24 & 25.01.02 (2 jours) Introduction au PC et à Windows 2000 au CERN : 29 - 30.1.02 (2 jours) LabView Base 1 : 4 - 6.2.02 (3 jours) LabView DAQ  (E) :  7 & 8.02.02 (2 days) Hands-on Object-Oriented Design & Programming with Java :&nbs...

  16. Places available**

    CERN Multimedia

    2003-01-01

    Places are available in the following courses : CLEAN-2002 : Working in a cleanroom (free course, registration required) : 2.4.03 (half-day, afternoon) LabView base 1/LabView Basics 1 (Langue à définir/ language to be decided) : 9 - 11.4.03 (3 jours/3 days) DISP-2003 - Spring II Term : Advanced Digital Signal Processing : 30.4, 7, 14, 21.5.03 (4 X 2-hour lectures) AutoCAD 2002 - niveau 1 : 29, 30.4 et 7, 8.5.03 (4 jours) AutoCAD 2002 - niveau 2 : 5 & 6.5.03 (2 jours) AutoCAD Mechanical 6 PowerPack (F) : 12, 13, 20, 21, 27 & 28.5.03(6 jours) Formation Siemens SIMATIC /Siemens SIMATIC Training : Introduction à STEP7 /Introduction to STEP7 : 3 & 4.6.03 (2 jours/2 days) Programmation STEP7/STEP7 Programming : 31.3 - 4.4.03 / 16 - 20.6.03 (5 jours/5 days) Réseau Simatic Net /Simatic Net Network : 15 & 16.4.03 / 26 & 27.6.03 These courses will be given in French or English following the requests. Cours de sécurité : Etre TSO au CERN : 3 sessions sont programmées pour 2003 : 25...

  17. Places available **

    CERN Multimedia

    2003-01-01

    Places are available in the following courses : CLEAN-2002 : Working in a cleanroom (free course, registration required): 11.4.03 (half-day, afternoon, ) LabView Basics 2 : 10 - 11.4.03 (3 days) DISP-2003 - Spring II Term : Advanced Digital Signal Processing : 30.4, 7, 14, 21.5.03 (4 X 2-hour lectures) AutoCAD 2002 - niveau 1 : 29, 30.4 et 7, 8.5.03 (4 jours) Oracle iDS Reports : Build Internet Reports : 5 - 9.5.03 (5 days) AutoCAD 2002 - niveau 2 : 5 & 6.5.03 (2 jours) AutoCAD Mechanical 6 PowerPack (F) : 12, 13, 20, 21, 27 & 28.5.03 (6 jours) Formation Siemens SIMATIC /Siemens SIMATIC Training : Introduction à STEP7 /Introduction to STEP7 : 3 & 4.6.03 (2 jours/2 days) Programmation STEP7/STEP7 Programming : 31.3 - 4.4.03 / 16 - 20.6.03 (5 jours/5 days) Réseau Simatic Net /Simatic Net Network : 15 & 16.4.03 / 26 & 27.6.03 These courses will be given in French or English following the requests. Cours de sécurité : Etre TSO au CERN : Prochaines sessions : 24, 25 & 27.6....

  18. Places available**

    CERN Multimedia

    2003-01-01

    Places are available in the following courses : DISP-2003 - Spring II Term : Advanced Digital Signal Processing : 30.4, 7, 14, 21.5.03 (4 X 2-hour lectures) Oracle iDS Reports : Build Internet Reports : 5 - 9.5.03 (5 days) LabView DAQ (language to be defined) : 8 & 9.5.03 AutoCAD Mechanical 6 PowerPack (F) : 12, 13, 20, 21, 27 & 28.5.03 (6 jours) AutoCAD 2002 - niveau 2 : 3 & 4.6.03 (2 jours) LabView DSC (language to be defined) : 19 & 20.6.03 Siemens SIMATIC Training : Introduction to STEP7 : 3 & 4.6.03 (2 days) STEP7 Programming : 16 - 20.6.03 (5 days) Simatic Net Network : 15 & 16.4.03 / 26 & 27.6.03 (sessions of 2 days) These courses will be given in French or English following the requests. Cours de sécurité : Etre TSO au CERN : Prochaines sessions : 24, 25 & 27.6.03 - 4, 5 & 7.11.03 (session de 3 jours) If you wish to participate in one of these courses, please discuss with your supervisor and apply electronically directly from the course description ...

  19. PLACES AVAILABLE

    CERN Multimedia

    Monique Duval

    2002-01-01

    Places are available in the following courses: Habilitation électrique : recyclage HT/BT : 11 - 15.3.2002  (2 * 2 heures) PVSS Basics :  8 - 12.4.02  (5 days) ELEC-2002 : Spring Term :  9, 11, 16, 18, 23, 25, 30.4.02 (7 * 2.5 hours) LabVIEW base 1 : 22 - 24.4.02 (3 jours) LabVIEW DSC (F) 25 & 26.4.02 (2 jours) LabVIEW Basics 2 : 13 & 14.5.02 (2 days) LabVIEW DAQ (F) : 15 & 16.5.02 (2 jours) Cours sur la migration AutoCAD :   AutoCAD : Mise à jour AutoCAD r-14 vers 2002 (2 jours) AutoCAD Mechanical PowerPack 6 basé sur AutoCAD 2002 (5 jours) If you wish to participate in one of these courses, please discuss with your supervisor and apply electronically directly from the course description pages that can be found on the Web at : Technical Training or fill in an 'application for training' form available from your Divisional Secretariat or from your DTO (Divisional Training Officer). Applica...

  20. Places available**

    CERN Multimedia

    2003-01-01

    Places are available in the following courses : CLEAN-2002 : Working in a cleanroom (free course, registration required): 11.4.03 (half-day, afternoon, ) LabView Basics 2 : 10 - 11.4.03 (3 days) DISP-2003 - Spring II Term : Advanced Digital Signal Processing : 30.4, 7, 14, 21.5.03 (4 X 2-hour lectures) AutoCAD 2002 - niveau 1 : 29, 30.4 et 7, 8.5.03 (4 jours) Oracle iDS Reports : Build Internet Reports : 5 - 9.5.03 (5 days) AutoCAD 2002 - niveau 2 : 5 & 6.5.03 (2 jours) AutoCAD Mechanical 6 PowerPack (F) : 12, 13, 20, 21, 27 & 28.5.03(6 jours) Formation Siemens SIMATIC /Siemens SIMATIC Training : Introduction à STEP7 /Introduction to STEP7 : 3 & 4.6.03 (2 jours/2 days) Programmation STEP7/STEP7 Programming : 31.3 - 4.4.03 / 16 - 20.6.03 (5 jours/5 days) Réseau Simatic Net /Simatic Net Network : 15 & 16.4.03 / 26 & 27.6.03 These courses will be given in French or English following the requests. Cours de sécurité : Etre TSO au CERN : Prochaines sessions : 24, 25 & 27.6...

  1. Places available**

    CERN Multimedia

    2003-01-01

    Places are available in the following courses : DISP-2003 - Spring II Term : Advanced Digital Signal Processing : 30.4, 7, 14, 21.5.03 (4 X 2-hour lectures) Programmation de pilotes périphériques : 5 - 8.5.03 (4 jours) Oracle iDS Reports : Build Internet Reports : 5 - 9.5.03 (5 days) LabView DAQ (language to be defined) : 8 & 9.5.03 AutoCAD Mechanical 6 PowerPack (F) : 12, 13, 20, 21, 27 & 28.5.0 (6 jours) FrontPage 2000 - niveau 1 : 20 & 21.5.03 (2 jours) AutoCAD 2002 - niveau 2 : 3 & 4.6.03 (2 jours) EXCEL 2000 - niveau 1 : 10 & 11.6.03 (2 jours) EXCEL 2000 - level 1 : 12 & 13.6.03 (2 days) PowerPoint 2000 (F) : 17 & 18.6.03 (2 jours) FrontPage 2000 - niveau 2 : 19 & 20.6.03 (2 jours) LabView DSC (langue à décider/language to be defined) : 19 & 20.6.03 EXCEL 2000 - niveau 2 : 24 & 25.6.03 (2 jours) Siemens SIMATIC Training : Introduction to STEP7 : 3 & 4.6.03 (2 days) STEP7 Programming : 16 - 20.6.03 (5 days) Simatic Net Network : 26 & 27.6.03 ...

  2. Places available**

    CERN Multimedia

    2003-01-01

    Places are available in the following courses : CLEAN-2002 : Working in a cleanroom (free course, registration required): 11.4.03 (half-day, afternoon) LabView Basics 2 : 10 - 11.4.03 (3 days) DISP-2003 - Spring II Term : Advanced Digital Signal Processing : 30.4, 7, 14, 21.5.03 (4 X 2-hour lectures) AutoCAD 2002 - niveau 1 : 29, 30.4 et 7, 8.5.03 (4 jours) Oracle iDS Reports : Build Internet Reports : 5 - 9.5.03 (5 days) AutoCAD 2002 - niveau 2 : 5 & 6.5.03 (2 jours) AutoCAD Mechanical 6 PowerPack (F) : 12, 13, 20, 21, 27 & 28.5.03(6 jours) Formation Siemens SIMATIC /Siemens SIMATIC Training : Introduction à STEP7 /Introduction to STEP7 : 3 & 4.6.03 (2 jours/2 days) Programmation STEP7/STEP7 Programming : 16 - 20.6.03 (5 jours/5 days) Réseau Simatic Net /Simatic Net Network : 15 & 16.4.03 / 26 & 27.6.03 These courses will be given in French or English following the requests. Cours de sécurité : Etre TSO au CERN : Prochaines sessions : 24, 25 & 27.6.03 - 4, 5 & 7....

  3. Places available**

    CERN Multimedia

    2003-01-01

    Places are available in the following courses : Introduction to PVSS : 10.3.03 (half-day, afternoon) CLEAN-2002 : Working in a cleanroom : 2.4.03 (half-day, afternoon, free course, registration required) LabView Basics 1 : 9 - 11.4.03 (3 days) Language to be decided. DISP-2003 - Spring II Term : Advanced Digital Signal Processing : 30.4, 7, 14, 21.5.03 (4 X 2-hour lectures). AutoCAD 2002 - niveau 1 : 29, 30.4 et 7, 8.5.03 (4 jours) AutoCAD 2002 - niveau 2 : 5 & 6.5.03 (2 jours) AutoCAD Mechanical 6 PowerPack (F) : 12, 13, 20, 21, 27 & 28.5.03 (6 jours) Siemens SIMATIC Training: Introduction to STEP7 : 3 & 4.6.03 (2 days) STEP7 Programming : 31.3 - 4.4.03 / 16 - 20.6.03 (5 days) Simatic Net Network : 15 & 16.4.03 / 26 & 27.6.03 These courses will be given in French or English following the requests. Cours de sécurité: Etre TSO au CERN : 3 sessions sont programmées pour 2003 : 25, 26 & 28.3.03 - 24, 25 & 27.6.03 - 4, 5 & 7.11.03 (sessions de 3 jours) ** The number o...

  4. PLACES AVAILABLE

    CERN Multimedia

    Monique Duval

    2002-01-01

    Places are available in the following courses: November 2002   Hands-on Object-Oriented Design and Programming with C++:  19 - 21.11.02  (3 days)  December 2002   LabVIEW - DSC (English) :  2 - 3.12.02  (2 days) AutoCAD 2002 - niveau 2 :  2 & 3.12.02  (2 jours) FileMaker (Français) :  2 - 5.12.02  (4 jours) PCAD Schémas - Débutants :  5 & 6.12.02  (2 jours) PCAD PCB - Débutants :  9 - 11.12.02  (3 jours) FrontPage 2000 - level 1:  9 & 10.12.02  (2 days) If you wish to participate in one of these courses, please discuss with your supervisor and apply electronically directly from the course description pages that can be found on the Web at : Technical Training or fill in an 'application for training' form available from your Divisional Secretariat or from your DTO (Divisiona...

  5. PLACES AVAILABLE

    CERN Multimedia

    Monique Duval

    2002-01-01

    Places are available in the following courses: November 2002   Java Programming Language level 1 :  28 & 29.11.02  (2 days) December 2002   LabVIEW - DSC (English) :  2 - 3.12.02  (2 days) FileMaker (Français) :  2 - 5.12.02  (4 jours) PCAD Schémas - Débutants :  5 & 6.12.02  (2 jours) PCAD PCB - Débutants :  9 - 11.12.02  (3 jours) FrontPage 2000 - level 1:  9 & 10.12.02  (2 days) If you wish to participate in one of these courses, please discuss with your supervisor and apply electronically directly from the course description pages that can be found on the Web at : Technical Training or fill in an 'application for training' form available from your Divisional Secretariat or from your DTO (Divisional Training Officer). Applications will be accepted in the order of their receipt. Technical Training M...

  6. PLACES AVAILABLE

    CERN Multimedia

    Monique Duval

    2002-01-01

    Places are available in the following courses: November 2002   Introduction to PVSS (free of charge): 11.11.02  (afternoon) EXCEL 2000 - niveau 1 :  12 & 13.11.02  (2 jours) CLEAN-2002: Working in a Cleanroom (English, free of charge):  13.11.2002  (afternoon) AutoCAD 2002 - niveau 1 :  14, 15, 21, 22.11.02  (4 jours) Hands-on Object-Oriented Design and Programming with C++:  19 - 21.11.02  (3 days)  EXCEL 2000 - niveau 2 :  25 & 26.11.02  (2 jours) FrontPage 2000 - niveau 1 :  27 & 28.11.02  (2 jours) December 2002   LabVIEW - DSC (English) :  2 - 3.12.02  (2 days) AutoCAD 2002 - niveau 2 :  2 & 3.12.02  (2 jours) FileMaker (Français) :  2 - 5.12.02  (4 jours) PCAD Schémas - Débutants :  5 & 6.12.02 ...

  7. PLACES AVAILABLE

    CERN Multimedia

    Technical training; Tel. 74924

    2001-01-01

    Places are available in the following courses: PROFIBUS : 25 - 26.9.01 (2 jours) PROFIBUS : 27 - 28.9.01 (2 days) Automates et réseaux de terrain : 3 - 4.10.2001 (2 jours) PCAD Schémas - débutants : 4 - 5.10.01 (2 jours) PCAD PCB - débutants : 8 - 10.10.01 (3 jours) Programmation TSX Premium 1 : 15 - 19.10.01 (5 jours) Programmation TSX Premium 1 : 22 - 26.10.01 (5 jours) Programming TSX Premium 2: 19 - 23.11.01 (5 days) Programmation TSX Premium 2 : 26 - 30.11.01 (5 jours) Autocad Migration support courses: a detailed calendar will be published shortly for this series of sessions which will start on 15.10.2001. Registration is already open AutoCAD : Mise à jour AutoCAD r-14 vers 2002 (2 jours) AutoCAD Mechanical PowerPack 6 basé sur AutoCAD 2002 (5 jours) The following LabView courses will be given in either English or French according to demand LabVIEW - Base 1 / LabVIEW - Basics 1 : 10 - 12.9.01 (3 jours / 3 days)...

  8. PLACES AVAILABLES

    CERN Multimedia

    Technical Training; Tel. 74924

    2001-01-01

    Places are available in the following courses: PVSS Basics : 20 - 24.8.01 (5 days) PROFIBUS : 25 - 26.9.01 (2 jours) PROFIBUS : 27 - 28.9.01 (2 days) PCAD Schémas - débutants : 4 - 5.10.01 (2 jours) PCAD PCB - débutants : 8 - 10.10.01 (3 jours) Programming TSX Premium 1: 15 - 19.10.01 (5 days) Programmation TSX Premium 1 : 22 - 26.10.01 (5 jours) Programming TSX Premium 2: 19 - 23.11.01 (5 days) Programmation TSX Premium 2 : 26 - 30.11.01 (5 jours) The following LabView courses will be given in either English or French according to demand LabVIEW - Base 1 / LabVIEW - Basics 1 : 10 - 12.9.01 (3 jours / 3 days) LabVIEW - DAQ / LabVIEW - DAQ : 13 - 14.9.01 (2 jours / 2 days) LabVIEW - Base 1 / LabVIEW - Basics 1 : 15 - 17.10.01 (3 jours / 3 days) LabVIEW - Base 2 / LabVIEW - Basics 2 : 18 - 19.10.01 (2 jours / 2 days) LabVIEW - Base 1 / LabVIEW - Basics 1 : 12 - 14.11.01 (3 jours / 3 days) LabVIEW - DAQ / LabVIEW - DAQ : 15 - 16.11.01 (2 jours / 2...

  9. PLACES AVAILABLE

    CERN Multimedia

    Monique Duval

    2002-01-01

    Places are available in the following courses: November 2002   LabView hands-on (bilingue/bilingual): 5.11.02 (matin/morning) LabView DAQ hands-on (bilingue/bilingual):  5.11.02  (après-midi afternoon) PCAD Schémas - Débutants :  5 & 6.11.02  (2 jours) PCAD PCB - Débutants :  9 - 11.11.02  (3 jours) Introduction au PC et Windows 2000 au CERN :  6 & 7.11.02  (2 jours) Oracle 8i : Access the Database with Java :  7 & 8.11.02  (2 days) Introduction to PVSS (free of charge):  11.11.2002 pm  (1/2 day) Basic PVSS:  12 - 14.11.02  (3 days) EXCEL 2000 - niveau 1 :  12 & 13.11.02  (2 jours) CLEAN-2002: Working in a Cleanroom (English, free of charge):  13.11.2002  (afternoon) LabView Base 1 :  13 - 15.11.02  (3 jours) AutoCAD 2002 - niveau 1 :  14, 15, 21, 22.11.02  (4 jours) LabVIEW - Advanced:  18 - 20.11.02  (3 days) Hands-on Object-Oriented Design and Programming with C++ :  19 - 21.11.02  (3 days)  LabVIEW - Basics 2:  21 - 22.11.02 ...

  10. Places available**

    CERN Multimedia

    2003-01-01

    Places are available in the following courses : EXCEL 2000 - niveau 1 : 10 & 11.6.03 (2 jours) Conception de PCB rapides dans le flot Cadence : 11.6.03 (matin) EXCEL 2000 - level 1 : 12 & 13.6.03 (2 days) Introduction to PVSS : 16.6.03 (p.m.) Basic PVSS : 17 - 19.6.03 (3 days) Réalisation de PCB rapides dans le flot Cadence : 17.6.03 (matin) PVSS - JCOP Framework Tutorial : 20.6.03 (1 day) EXCEL 2000 - niveau 2 : 24 & 25.6.03 (2 jours) Siemens SIMATIC Training : Introduction to STEP7 : 3 & 4.6.03 (2 jours/2 days) STEP7 Programming : 16 - 20.6.03 (5 jours/5 days) Simatic Net Network : 26 & 27.6.03 (2 jours/2 days) These courses will be given in French or English following the requests. Programmation automate Schneider : Programmation automate Schneider TSX Premium - 1er niveau : 10 - 13.6.03 (4 jours) - audience : toute personne qui veux maitriser la msie en uvre et la programmation d'un automate TSX Premium - objectifs : maitriser la mise en uvre et la programmation d'un autom...

  11. Places available**

    CERN Multimedia

    2003-01-01

    Places are available in the following courses : FrontPage 2000 - niveau 1 : 20 & 21.5.03 (2 jours) PIPES-2003 : Pratique du sertissage de tubes métalliques et multicouches : 21.5.03 (1 jour) Introduction à la CAO Cadence : de la saisie de schéma Concept-HDL au PCB : 20 & 22.5.03 (2 jours) AutoCAD 2002 - niveau 2 : 3 & 4.6.03 (2 jours) AutoCAD Mechanical 6 PowerPack (F) : 5, 6, 12, 13, 26, 27.6.03 (6 jours) EXCEL 2000 - niveau 1 : 10 & 11.6.03 (2 jours) Conception de PCB rapides dans le flot Cadence : 11.6.03 (matin) EXCEL 2000 - level 1 : 12 & 13.6.03 (2 days) PowerPoint 2000 (F) : 17 & 18.6.03 (2 jours) Réalisation de PCB rapides dans le flot Cadence : 17.6.03 (matin) FrontPage 2000 - niveau 2 : 19 & 20.6.03 (2 jours) LabView DSC (langue à décider/language to be defined) : 19 & 20.6.03 EXCEL 2000 - niveau 2 : 24 & 25.6.03 (2 jours) Siemens SIMATIC Training: Introduction to STEP7 : 3 & 4.6.03 (2 days) STEP7 Programming : 16 - 20.6.03 (5 days) Simatic...

  12. PLACES AVAILABLE

    CERN Multimedia

    Technical Training; Tel. 74924

    2001-01-01

    Places are available in the following courses: PVSS Basics : 20 - 24.8.01 (5 days) PROFIBUS : 25 - 26.9.01 (2 jours) PROFIBUS : 27 - 28.9.01 (2 days) PCAD Schémas - débutants : 4 - 5.10.01 (2 jours) PCAD PCB - débutants : 8 - 10.10.01 (3 jours) Programming TSX Premium 1: 15 - 19.10.01 (5 days) Programmation TSX Premium 1 : 22 - 26.10.01 (5 jours) Programming TSX Premium 2: 19 - 23.11.01 (5 days) Programmation TSX Premium 2 : 26 - 30.11.01 (5 jours) The following LabView courses will be given in either English or French according to demand LabVIEW - Base 1 / LabVIEW - Basics 1 : 10 - 12.9.01 (3 jours / 3 days) LabVIEW - DAQ / LabVIEW - DAQ : 13 - 14.9.01 (2 jours / 2 days) LabVIEW - Base 1 / LabVIEW - Basics 1 : 15 - 17.10.01 (3 jours / 3 days) LabVIEW - Base 2 / LabVIEW - Basics 2 : 18 - 19.10.01 (2 jours / 2 days) LabVIEW - Base 1 / LabVIEW - Basics 1 : 12 - 14.11.01 (3 jours / 3 days) LabVIEW - DAQ / LabVIEW - DAQ : 15 - 16.11.01 (2 jours / 2...

  13. PLACES AVAILABLE

    CERN Multimedia

    Technical Training; Tel. 74924

    2001-01-01

    Places are available in the following courses: Introduction à Windows 2000 au CERN : 2 sessions de _ journée les 24 et 25.9.01 PROFIBUS : 25 - 26.9.01 (2 jours) PROFIBUS : 27 - 28.9.01 (2 days) PowerPoint 2000 : 1 et 2.10.01 (2 jours) EXCEL 2000 - niveau 1 : 3 et 4.10.01 (2 jours) Automates et réseaux de terrain : 3 - 4.10.2001 (2 jours) PCAD Schémas - débutants : 4 - 5.10.01 (2 jours) Introduction à Outlook : 5.10.01 (1 journée) Frontpage 2000 - niveau 1 : 8 et 9.10.01 (2 jours) PCAD PCB - débutants : 8 - 10.10.01 (3 jours) C++ for Particle Physicists : 8 - 12.10.01 (6 3-hour lectures) MS-Project 2000 - niveau 1 : 15 - 18.10.01 (4 demi-journées) LabView Basics 1 :  15 - 17.10.01  (3 days) Programmation TSX Premium 1 : 15 - 19.10.01 (5 jours) WORD 2000 : importer et manipuler des images : 19.10.01 (1 journée) Programmation TSX Premium 1 : 22 - 26.10.01...

  14. PLACES AVAILABLE

    CERN Multimedia

    Technical Training; Tel. 74924

    2001-01-01

    Places are available in the following courses: Cadence Board Design tools : Upgrading to release 14 :  3 1-day sessions on 9, 10 & 11.10.01 MS-Project 2000 - niveau 1 : 15 - 18.10.01 (4 demi-journées) LabView Base 2 : 18 & 19.10.01 (2 jours) WORD 2000 : importer et manipuler des images : 19.10.01 (1 journée) Contract Follow-up (F) :  30.10.01 (1/2 journée) The CERN Engineering Data Management System for Electronics Design :  30.10.01 (1 day) UNIX pour non-programmeurs : 5 - 7.11.01 (3 jours) The Java programming language Level 1: 8 - 9.11.01 (2 days) LabView Base 1 : 12 - 14.11.01 (3 jours) Introduction to PERL 5 :  15 - 16.11.01  (2 days) Introduction to XML :  19 - 20.11.01 (2 days) Programming TSX Premium 1 :  19 - 23.11.01  (5 days) Introduction to C Programming :  21- 23.11.01 (3 days) The Java programming language Level 2:  26 - 28.11.01 (...

  15. PLACES AVAILABLE

    CERN Multimedia

    Technical Training; Tel. 74924

    2001-01-01

    Places are available in the following courses: Introduction à Windows 2000 au CERN : 2 sessions de _ journée les 24 et 25.9.01 PROFIBUS : 25 - 26.9.01 (2 jours) PROFIBUS : 27 - 28.9.01 (2 days) EXCEL 2000 - niveau 1 : 3 et 4.10.01 (2 jours) Automates et réseaux de terrain : 3 - 4.10.2001 (2 jours) Introduction à Outlook : 5.10.01 (1 journée) Frontpage 2000 - niveau 1 : 8 et 9.10.01 (2 jours) C++ for Particle Physicists : 8 - 12.10.01 (6 lectures) MS-Project 2000 - niveau 1 : 15 - 18.10.01 (4 demi-journées) Programmation TSX Premium 1 : 15 - 19.10.01 (5 jours) WORD 2000 : importer et manipuler des images : 19.10.01 (1 journée) Programmation TSX Premium 1 : 22 - 26.10.01 (5 jours) UNIX pour non-programmeurs : 5 - 7.11.01 (3 jours) The Java programming language Level 1: 8 - 9.11.01 (2 days) Introduction to PERL 5 :  15 - 16.11.01  (2 days) Introduction to XML :  19 - 20.11.01 (2...

  16. PLACES AVAILABLE

    CERN Multimedia

    Technical Training; Tel. 74924

    2001-01-01

    Places are available in the following courses: EXCEL 2000 - niveau 1 : 3 et 4.10.01 (2 jours) Automates et réseaux de terrain : 3 - 4.10.2001 (2 jours) Introduction à Outlook : 5.10.01 (1 journée) C++ for Particle Physicists : 8 - 12.10.01 (6 lectures) Cadence Board Design tools : Upgrading to release 14 : 3 1-day sessions on 9, 10 & 11.10.01 MS-Project 2000 - niveau 1 : 15 - 18.10.01 (4 demi-journées) LabView Base 2 : 18 & 19.10.01 (2 jours) WORD 2000 : importer et manipuler des images : 19.10.01 (1 journée) The CERN Engineering Data Management System for Electronics Design :  30.10.01 (1 day) UNIX pour non-programmeurs : 5 - 7.11.01 (3 jours) The Java programming language Level 1: 8 - 9.11.01 (2 days) Introduction to PERL 5 :  15 - 16.11.01  (2 days) Introduction to XML :  19 - 20.11.01 (2 days) Programming TSX Premium 1 :  19 - 23.11.01  (5 days) Introd...

  17. PLACES AVAILABLE

    CERN Multimedia

    Technical Training; Tel. 74924

    2001-01-01

    Places are available in the following courses: MS-Project 2000 - niveau 1 : 15 - 18.10.01 (4 demi-journées) LabView Base 2 : 18 & 19.10.01 (2 jours) WORD 2000 : importer et manipuler des images : 19.10.01 (1 journée) Contract Follow-up (F) : 30.10.01 (1/2 journée) The CERN Engineering Data Management System for Electronics Design :  30.10.01 (1 day) UNIX pour non-programmeurs : 5 - 7.11.01 (3 jours) The Java programming language Level 1: 8 - 9.11.01 (2 days) LabView Base 1 : 12 - 14.11.01 (3 jours) Automates et réseaux de terrain : 13 & 14.11.01 (2 jours) Introduction to PERL 5 :  15 - 16.11.01  (2 days) Introduction to XML :  19 - 20.11.01 (2 days) Programming TSX Premium 1 :  19 - 23.11.01  (5 days) Introduction to C Programming :  21- 23.11.01 (3 days) The Java programming language Level 2:  26 - 28.11.01 (3 days) Programmation TSX Premium 2 : 26 ...

  18. PLACES AVAILABLE

    CERN Multimedia

    Monique Duval

    2002-01-01

    Places are available in the following courses: LabView Base 1 :  23 - 25.9.02  (3 jours) Object-Oriented Analysis & Design using UML:  25 - 27.9.02  (3 days) LabView DAQ (E):  26 - 27.9.02  (2 days) Introduction to Oracle 8i : SQL and PL/SQL:  7 - 11.10.02  (5 days) CLEAN-2002 : Working in a Cleanroom (free of charge):  10.10.02  (half-day, p.m.) AutoCAD 2002 - niveau 2 :  14 - 15.10.02  (2 jours) Introduction à DesignSpace :  16.10.02  (1 journée) Introduction to DesignSpace:  17.10.02  (1 day) AutoCAD 2002 - Level 1:  17, 18, 24, 25.10.02  (4 days) AutoCAD Mechanical 6 PowerPack (F) :  21, 22, 23.10 et 4, 5, 6.11.02  (6 jours) Introduction à ANSYS/Introduction to ANSYS (langue à définir suivant demande/ Language to be chosen according to demand):...

  19. PLACES AVAILABLE

    CERN Multimedia

    Monique Duval

    2002-01-01

    Places are available in the following courses: Java 2 Enterprise Edition - Part 2: Enterprise JavaBeans:  18 - 20.9.02  (3 days) AutoCAD 2002 - niveau 1 :  19, 20, 26, 27.9.02  (4 jours) LabView Base 1 :  23 - 25.9.02  (3 jours) Object-Oriented Analysis & Design using UML:  25 - 27.9.02  (3 days) LabView DAQ (E):  26 - 27.9.02  (2 days) Introduction to Oracle 8i : SQL and PL/SQL:  7 - 11.10.02  (5 days) CLEAN-2002 : Working in a Cleanroom (free of charge):  10.10.02  (half-day, p.m.) AutoCAD 2002 - niveau 2 :  14 - 15.10.02  (2 jours) Introduction à DesignSpace :  16.10.02  (1 journée) Introduction to DesignSpace:  17.10.02  (1 day) AutoCAD 2002 - Level 1:  17, 18, 24, 25.10.02  (4 days) AutoCAD Mechanical 6 PowerPack (F) :  21, 22, 23.10 et 4, 5, 6.11....

  20. PLACES AVAILABLE

    CERN Multimedia

    Technical Training; Tel. 74924

    2001-01-01

    Places are available in the following courses: Automates et réseaux de terrain : 13 & 14.11.01 (3 jours) Introduction à Windows 2000 au CERN : 12 - 14.11.01 (1/2 journée) Introduction to Windows 2000 at CERN :  14.11.01  (half-day) Introduction to PERL 5 :  15 - 16.11.01  (2 days) Sécurité dans les installations cryogéniques : 21 - 22.11.2001 (2 demi-journées) Introduction to C Programming :  21- 23.11.01 (3 days) Programmation TSX Premium 2 : 26 - 30.11.01 (5 jours) Contract Follow-up (F) : 26.11.01 (1/2 journée) Object-Oriented Analysis and Design :  27 - 30.11.2001  (4 days) Introduction to the CERN Engineering Data Management System :  30.11.2001 (1 day) Electromagnetic Compatibility (EMC): Introduction (bilingual) :  3.12.01 (half-day) Introduction to the CERN Engineering Data Management System : 07.12.2001...

  1. PLACES AVAILABLE

    CERN Multimedia

    Technical Training; Tel. 74924

    2001-01-01

    Places are available in the following courses: Contract Follow-up (F) : 30.10.01 (1/2 journée) The CERN Engineering Data Management System for Electronics Design :  30.10.01 (1 day) UNIX pour non-programmeurs : 5 - 7.11.01 (3 jours) Nouveautés d'EXCEL : 5.11.01 (1/2 journée) Introduction a Windows 2000 au CERN : 6.11.01 (1/2 journée) The Java programming language Level 1: 8 - 9.11.01 (2 days) LabView Base 1 : 12 - 14.11.01 (3 jours) Automates et réseaux de terrain : 13 & 14.11.01 (2 jours) Introduction to PERL 5 :  15 - 16.11.01  (2 days) Introduction to XML :  19 - 20.11.01 (2 days) Programming TSX Premium 1 :  19 - 23.11.01  (5 days) Introduction to C Programming :  21- 23.11.01 (3 days) The Java programming language Level 2:  26 - 28.11.01 (3 days) Programmation TSX Premium 2 : 26 - 30.11.01 (5 jours) Autocad Migration support courses: a detail...

  2. PLACES AVAILABLE

    CERN Multimedia

    Technical Training; Tel. 74924

    2001-01-01

    Places are available in the following courses: Contract Follow-up (F) : 30.10.01 (1/2 journée) The CERN Engineering Data Management System for Electronics Design :  30.10.01 (1 day) Nouveautés d'Excel 2000 : 5.11.01 (1/2 journée) UNIX pour non-programmeurs : 5 - 7.11.01 (3 jours) Introduction à Windows 2000 au CERN : 6.11.01 (1/2 journée) The Java programming language Level 1: 8 - 9.11.01 (2 days) LabView Base 1 : 12 - 14.11.01 (3 jours) LabVIEW DAQ (F) : 15 & 16.11.01 (2 jours) Automates et réseaux de terrain : 13 & 14.11.01 (2 jours) Introduction to PERL 5 :  15 - 16.11.01  (2 days) LabVIEW - DAQ : 15 - 16.11.01 (2 jours) Introduction to XML :  19 - 20.11.01 (2 days) Introduction to C Programming :  21- 23.11.01 (3 days) Programmation TSX Premium 2 : 26 - 30.11.01 (5 jours) Object-Oriented Analysis and Design :  27 - 30.11.2001 (4 days) Hands...

  3. PLACES AVAILABLE

    CERN Multimedia

    Technical Training; Tel. 74924

    2001-01-01

    Places are available in the following courses: Nouveautés d'EXCEL : 5.11.01 (1/2 journée) Introduction a Windows 2000 au CERN : 6.11.01 (1/2 journée) UNIX pour non-programmeurs : 5 - 7.11.01 (3 jours) Design Patterns :  7 - 8.11.01 (2 days) The Java programming language Level 1: 8 - 9.11.01 (2 days) Automates et réseaux de terrain : 13 & 14.11.01 (3 jours) Introduction à Windows 2000 au CERN : 12 - 14.11.01 (1/2 journée) Introduction to Windows 2000 at CERN :  14.11.01  (half-day) Introduction to PERL 5 :  15 - 16.11.01  (2 days) Introduction to C Programming :  21- 23.11.01 (3 days) Programmation TSX Premium 2 : 26 - 30.11.01 (5 jours) Contract Follow-up (F) : 26.11.01 (1/2 journée) Object-Oriented Analysis and Design :  27 - 30.11.2001  (4 days) Hands-on Object-Oriented Design and Programming with C++ :  11 - 13.12.2...

  4. PLACES AVAILABLE

    CERN Multimedia

    Monique Duval

    2002-01-01

    Places are available in the following courses: ELEC-2002 : Spring Term :  9, 11, 16, 18, 23, 25, 30.4.02 (7 * 2.5 hours) Object-Oriented Analysis & Design: 16 - 19.4.02  (4 days) The CERN Engineering Data Management System for Advanced users:  16.4.02  (1 day) Migration from AutoCAD 14 towards AutoCAD Mechanical6 PowerPack:  17 - 19.4 and 2 &3.5.02  (5 days) AutoCAD - niveau 1 : 22, 23, 29, 30.4 et 6, 7.5.02 (6 jours) LabVIEW base 1 : 22 - 24.4.02 (3 jours) CLEAN 2002 : working in a cleanroom:  24.4.02  (half-day, pm) LabVIEW DSC (F) 25 & 26.4.02 (2 jours) AutoCAD : Mise à jour AutoCAD r-14 vers 2002 : 25 & 26.4.02 (2 jours) Cotations selon les normes GPS de l'ISO : 29 - 30.4.02 (2 jours) Introduction to the CERN Engineering Data Management System:  7.5.02  (1 day) LabVIEW Basics 2 : 13 & 14.5.02 (2 days) AutoCAD Mechanical 6 PowerPack (F) : 13-...

  5. PLACES AVAILABLE

    CERN Multimedia

    Monique Duval

    2002-01-01

    Places are available in the following courses: Introduction to the CERN Engineering Data Management System:  7.5.02  (1 day) LabVIEW Basics 2: 13 & 14.5.02 (2 days) AutoCAD Mechanical 6 PowerPack (F) : 13-14, 17, 21, 27-28.5.02 (6 jours) WorldFIP - Généralités : 14.5.2002 (1/2 journée) WorldFIP - Développer avec MicroFIP HANDLER : 14.5 - après-midi, 15.5.02 - matin (1 jour) WorldFIP - FullFIP FDM : FIP Device Manager (F) : 15.5 - après-midi, 16.5.02 - matin (1 jour) LabVIEW DAQ (F) : 15 & 16.5.02 (2 jours) EXCEL 2000 - niveau 2 : 22 & 23.5.02 (2 jours) The CERN Engineering Data Management System for Advanced users:  30.5.02  (1 day) LabVIEW Basics 1:  3 - 5.6.02  (3 days) AutoCAD 2002 - condensé : 4 - 6.6.02 (3 jours) LabVIEW DAQ (E):  6 & 7.6.02  (2 days) AutoCAD 2002 - Level 1:  10 - ...

  6. PLACES AVAILABLE

    CERN Multimedia

    Monique Duval

    2002-01-01

    Places are available in the following courses: The CERN Engineering Data Management System for Advanced users : 16.4.02  (1 day) Migration from AutoCAD 14 towards AutoCAD Mechanical6 PowerPack:  17 - 19.4 and 2 &3.5.02  (5 days) AutoCAD - niveau 1 : 22, 23, 29, 30.4 et 6, 7.5.02 (6 jours) LabVIEW base 1 : 22 - 24.4.02 (3 jours) CLEAN 2002 : working in a cleanroom:  24.4.02  (half-day, pm) LabVIEW DSC (F) 25 & 26.4.02 (2 jours) AutoCAD : Mise à jour AutoCAD r-14 vers 2002 : 25 & 26.4.02 (2 jours) Cotations selon les normes GPS de l'ISO : 29 - 30.4.02 (2 jours) Introduction to the CERN Engineering Data Management System:  7.5.02  (1 day) LabVIEW Basics 2: 13 & 14.5.02 (2 days) AutoCAD Mechanical 6 PowerPack (F) : 13-14, 17, 21, 27-28.5.02 (6 jours) WorldFIP - Généralités : 14.5.2002 (1/2 journée) WorldFIP - Développer avec Micr...

  7. PLACES AVAILABLE

    CERN Multimedia

    Monique Duval

    2002-01-01

    Places are available in the following courses: LabVIEW Basics 2: 13 & 14.5.02 (2 days) WorldFIP - Généralités : 14.5.2002 (1/2 journée) WorldFIP - Développer avec MicroFIP HANDLER : 14.5 - après-midi, 15.5.02 - matin (1 jour) WorldFIP - FullFIP FDM : FIP Device Manager (F) : 15.5 - après-midi, 16.5.02 - matin (1 jour) LabVIEW DAQ (F) : 15 & 16.5.02 (2 jours) EXCEL 2000 - niveau 2 : 22 & 23.5.02 (2 jours) The CERN Engineering Data Management System for Advanced users:  30.5.02  (1 day) LabVIEW Basics 1:  3 - 5.6.02  (3 days) AutoCAD 2002 - condensé : 4 - 6.6.02 (3 jours) LabVIEW DAQ (E):  6 & 7.6.02  (2 days) AutoCAD 2002 - Level 1:  10 - 12 and 24 - 26.6.02  (6 days) If you wish to participate in one of these courses, please discuss with your supervisor and apply electronically directly from the c...

  8. PLACES AVAILABLE

    CERN Multimedia

    Monique Duval

    2002-01-01

    Places are available in the following courses: LabVIEW base 1 : 22 - 24.4.02 (3 jours) CLEAN 2002 : working in a cleanroom:  24.4.02  (half-day, pm) LabVIEW DSC (F) 25 & 26.4.02 (2 jours) AutoCAD : Mise à jour AutoCAD r-14 vers 2002 : 25 & 26.4.02 (2 jours) Cotations selon les normes GPS de l'ISO : 29 - 30.4.02 (2 jours) Introduction to the CERN Engineering Data Management System:  7.5.02  (1 day) LabVIEW Basics 2: 13 & 14.5.02 (2 days) AutoCAD Mechanical 6 PowerPack (F) : 13-14, 17, 21, 27-28.5.02 (6 jours) WorldFIP - Généralités : 14.5.2002 (1/2 journée) WorldFIP - Développer avec MicroFIP HANDLER : 14.5 - après-midi, 15.5.02 - matin (1 jour) WorldFIP - FullFIP FDM : FIP Device Manager (F) : 15.5 - après-midi, 16.5.02 - matin (1 jour) LabVIEW DAQ (F) : 15 & 16.5.02 (2 jours) EXCEL 2000 - niveau 2 : 22 & 23.5.02 (2 jours)...

  9. ‘We are a community [but] that takes a certain amount of energy’: Exploring shared visions, social action, and resilience in place-based community-led energy initiatives

    International Nuclear Information System (INIS)

    Parkhill, K.A.; Shirani, F.; Butler, C.; Henwood, K.L.; Groves, C.; Pidgeon, N.F.

    2015-01-01

    Highlights: • We engage with conceptual characteristics of 3 community-led energy case studies. • We examine data from interviews to explore the issues community energy groups face. • Shared visions, social action and social resilience are important to community energy. • Creating and maintaining shared visions, social action and social resilience is extremely challenging. - Abstract: In UK energy policy, community-led energy initiatives are increasingly being imbued with transformative power to facilitate low carbon transitions. The ways that such expectations for communities are manifesting in practice remains, however, relatively poorly understood. In particular, key conceptual developments in unpacking what constitutes ‘community’ that highlight the significance of ‘place’ along with important characteristics, such as shared visions, collective social action, and resilience, have yet to be comprehensively explored in the context of community-led energy initiatives. This paper uses an interpretive stance to engage with these conceptual ideas about community and provides insights into the nature of community and its meaning for developing energy-related initiatives and realising the wider goals of energy policy. The paper draws on data from in-depth qualitative, longitudinal interviews undertaken in two residential communities and one purely workplace-based community, which are engaged in community energy initiatives. We argue that there are difficulties and ambiguities in creating shared visions, achieving social action, and developing resilience that are related to the specificities of community in place, but that all three characteristics are likely to be important for the making of sustainable places

  10. Studies into laser ignition of confined pyrotechnics

    Energy Technology Data Exchange (ETDEWEB)

    Ahmad, S.R.; Russell, D.A. [Centre for Applied Laser Spectroscopy, DASSR, Defence Academy, Cranfield University, Shrivenham, Swindon (United Kingdom)

    2008-10-15

    Ignition tests were carried out on three different pyrotechnics using laser energy from the multimode output from an Ar-Ion laser (av) at 500 nm and a near-IR diode laser pigtailed to a fibre optic cable and operating at 808 nm. The pyrotechnics investigated were: G20 black powder, SR44 and SR371C. The confined ignition tests were conducted in a specially designed ignition chamber. Pyrotechnics were ignited by a free space beam entering the chamber through an industrial sapphire window in the case of the Ar-ion laser. For the NIR diode laser, fibre was ducted through a block into direct contact with the pyrotechnic. The Ar-Ion laser was chosen as this was found to ignite all three pyrotechnics in the unconfined condition. It also allowed for a direct comparison of confined/unconfined results to be made. The threshold laser flux densities to initiate reproducible ignitions at this wavelength were found to be between {proportional_to}12.7 and {proportional_to}0.16 kW cm{sup -2}. Plotted on the ignition maps are the laser flux densities versus the start of ignition times for the three confined pyrotechnics. It was found from these maps that the times for confined ignition were substantially lower than those obtained for unconfined ignition under similar experimental conditions. For the NIR diode laser flux densities varied between {proportional_to}6.8 and {proportional_to}0.2 kW cm{sup -2}. The minimum ignition times for the NIR diode laser for SR371C ({proportional_to}11.2 ms) and G20 ({proportional_to}17.1 ms) were faster than those achieved by the use of the Ar-ion laser. However, the minimum ignition time was shorter ({proportional_to}11.7 ms) with the Ar-ion laser for SR44. (Abstract Copyright [2008], Wiley Periodicals, Inc.)

  11. Pulse length assessment of compact ignition tokamak designs

    International Nuclear Information System (INIS)

    Stotler, D.P.; Pomphrey, N.

    1989-07-01

    A time-dependent zero-dimensional code has been developed to assess the pulse length and auxiliary heating requirements of Compact Ignition Tokamak (CIT) designs. By taking a global approach to the calculation, parametric studies can be easily performed. The accuracy of the procedure is tested by comparing with the Tokamak Simulation Code which uses theory-based thermal diffusivities. A series of runs is carried out at various levels of energy confinement for each of three possible CIT configurations. It is found that for cases of interest, ignition or an energy multiplication factor Q /approxreverse arrowgt/ 7 can be attained within the first half of the planned five-second flattop with 10--40 MW of auxiliary heating. These results are supported by analytic calculations. 18 refs., 7 figs., 2 tabs

  12. Electron Shock Ignition of Inertial Fusion Targets

    International Nuclear Information System (INIS)

    Shang, W. L.; Betti, R.; Hu, S. X.; Woo, K.; Hao, L.

    2017-01-01

    Here, it is shown that inertial fusion targets designed with low implosion velocities can be shock ignited using laser–plasma interaction generated hot electrons (hot-e) to obtain high-energy gains. These designs are robust to multimode asymmetries and are predicted to ignite even for significantly distorted implosions. Electron shock ignition requires tens of kilojoules of hot-e, which can only be produced on a large laser facility like the National Ignition Facility, with the laser to hot-e conversion efficiency greater than 10% at laser intensities ~10 16 W/cm 2 .

  13. Brand new authentic places

    DEFF Research Database (Denmark)

    Stender, Marie

    the relation and interplay between the two. This study strives to fill this gap by ethnographically tracing the process from design to occupancy including the role of branding as a means to create authenticity. The concept of authenticity is often associated with old houses and neighbourhoods, but also in new......How are places and material surroundings ascribed with meaning when new residential neighbourhoods are designed, branded and taken into use? Existing research on housing, neighbourhoods and urban design tends to take the perspective of either the architect or the user rather than to explore...... neighbourhoods stories of authenticity seems to be of great importance giving value and identity to place and people. By way of design and branding new places are implied with notions of the real, the original and the unique referring to e.g. its historical past, architectural uniqueness, sustainability or sense...

  14. Ignition of turbulent swirling n-heptane spray flames using single and multiple sparks

    Energy Technology Data Exchange (ETDEWEB)

    Marchionea, T.; Ahmeda, S.F.; Mastorakos, E. [Department of Engineering, University of Cambridge (United Kingdom)

    2009-01-15

    This paper examines ignition processes of an n-heptane spray in a flow typical of a liquid-fuelled burner. The spray is created by a hollow-cone pressure atomiser placed in the centre of a bluff body, around which swirling air induces a strong recirculation zone. Ignition was achieved by single small sparks of short duration (2 mm; 0.5 ms), located at various places inside the flow so as to identify the most ignitable regions, or larger sparks of longer duration (5 mm; 8 ms) repeated at 100 Hz, located close to the combustion chamber enclosure so as to mimic the placement and characteristics of a gas turbine combustor surface igniter. The air and droplet velocities, the droplet diameter, and the total (i.e. liquid plus vapour) equivalence ratio were measured in inert flow by phase Doppler anemometry and sampling respectively. Fast camera imaging suggested that successful ignition events were associated with flamelets that propagated back towards the spray nozzle. Measurements of ignition probability with the single spark showed that localised ignition inside the spray is more likely to result in successful flame establishment when the spark is located in a region of negative velocity, relatively small droplet Sauter mean diameter, and mean equivalence ratio within the flammability limits. Ignition with the single spark was not possible at the location where the multiple spark experiments were performed. For those, the multiple spark sequence lasted approximately 1 to 5 s. It was found that a long spark sequence increases the ignition efficiency, which reached a maximum of 100% at the axial distance where the recirculation zone had maximum width. Ignition was not feasible with the spark downstream of about two burner diameters. Visualisation showed that small flame kernels emanate very often from the spark, which can be stretched as far as 20 mm from the electrodes by the turbulent velocity fluctuations. These kernels survive very little time. Successful overall

  15. Places disponibles/Places available

    CERN Multimedia

    2004-01-01

    Si vous désirez participer à l'un des cours suivants, veuillez en discuter avec votre superviseur et vous inscrire électroniquement en direct depuis les pages de description des cours dans le Web que vous trouvez à l'adresse : http://www.cern.ch/Training/ ou remplissez une « demande de formation » disponible auprès du Secrétariat de votre Division ou de votre DTO (Délégué divisionnaire à la formation). Les places seront attribuées dans l'ordre de réception des inscriptions. If you wish to participate in one of the following courses, please discuss with your supervisor and apply electronically directly from the course description pages that can be found on the Web at: http://www.cern.ch/Training/ or fill in an "application for training" form available from your Divisional Secretariat or from your DTO (Divisional Training Off...

  16. Effects of ignition parameters on combustion process of a rotary engine fueled with natural gas

    International Nuclear Information System (INIS)

    Fan, Baowei; Pan, Jianfeng; Liu, Yangxian; Zhu, Yuejin

    2015-01-01

    rate. However, the drawback of this improved combustion was the slight increase in NO emissions. Under the computational condition, when the trailing spark plug scheme of case C coupled with an ignition timing of 50 °CA (BTDC) was compared with the spark plug location and the ignition timing of the original engine, it showed a 27.4% increase in the peak pressure. Taking the limited increase of NO exhaust into consideration it was the best ignition allocation scheme under the computational condition. This study provided a theoretical foundation for the determination of best ignition position and ignition timing under different working conditions

  17. Physical characteristics of welding arc ignition process

    Science.gov (United States)

    Shi, Linan; Song, Yonglun; Xiao, Tianjiao; Ran, Guowei

    2012-07-01

    The existing research of welding arc mainly focuses on the stable combustion state and the research on the mechanism of welding arc ignition process is quite lack. The tungsten inert gas(TIG) touch arc ignition process is observed via a high speed camera and the high time resolution spectral diagnosis system. The changing phenomenon of main ionized element provided the electrons in the arc ignition is found. The metallic element is the main contributor to provide the electrons at the beginning of the discharging, and then the excitated shielding gas element replaces the function of the metallic element. The electron density during the period of the arc ignition is calculated by the Stark-broadened lines of Hα. Through the discussion with the repeatability in relaxation phenomenon, the statistical regularity in the arc ignition process is analyzed. The similar rules as above are observed through the comparison with the laser-assisted arc ignition experiments and the metal inert gas(MIG) arc ignition experiments. This research is helpful to further understanding on the generation mechanism of welding arc ignition and also has a certain academic and practical significance on enriching the welding physical theoretical foundation and improving the precise monitoring on automatic arc welding process.

  18. Modelling piloted ignition of wood and plastics

    NARCIS (Netherlands)

    Blijderveen, M.; Bramer, Eduard A.; Brem, Gerrit

    2012-01-01

    To gain insight in the startup of an incinerator, this article deals with piloted ignition. A newly developed model is described to predict the piloted ignition times of wood, PMMA and PVC. The model is based on the lower flammability limit and the adiabatic flame temperature at this limit. The

  19. Heating and ignition of small wood cylinders

    Science.gov (United States)

    Wallace L. Fons

    1950-01-01

    The literature provides limited information on the time of ignition of wood under conditions of rapid heating such as occur in forest and structure fires. An investigation was made of ease of ignition as affected by such physical properties of wood as initial temperature, size, and moisture content and by temperature of ambient gas or rate of heating. Temperature-time...

  20. ARIANE 5 upper-stage ignition conditions improvement, and return to operation with ''Envisat'' payload

    Science.gov (United States)

    Dutheil, J. Ph.; Langel, G.

    2003-08-01

    ARIANE 5 experienced a flight anomaly with the 10 th model mission (F 510), having placed its both satellites in a lower orbit than the planned GTO. Only one satellite (Artemis) could be retrieved due to its own propulsion systems. Arianespace, CNES and Astrium-GmbH (former DaimlerChrysler Aerospace Dasa) immediately set up a recovery team, combining forces for carrying deep and schedule-driven investigations, and later qualifying recovery measures. A failure in such an important program: is immediately triggering a large "post-shock" reaction from the ARIANE community implied in the relevant business and technology. The investigation fields are summarised in the following chapters, showing how failure analysis, engineering investigations and basic research have been combined in order to have a schedule and methodic efficient approach. The combination of all available European resources in space vehicle design has been implemented, involving industry, agency technical centers and research laboratories. The investigation methodology applied has been driven by the particular situation of a flight anomaly investigation, which has to take into account the reduced amount of measurement available in flight and the necessary combination with ground test data for building a strategy to reach identification of possible failure scenario. From the investigations and from extensive sensitivity characterisation test of EPS engine (AESTUS) ignition transient, stability margins have been deeply investigated and introduced in the post-anomaly upgraded stage design. The identification and implementation of recovery measures, extended as well to - potential ignition margin reduction factors even beyond the observed flight anomaly allowed to establish a robust complementary qualification status, thus allowing resuming of operational flight, starting with the valuable "Envisat" payload of European Space Agency, dedicated to earth and climate monitoring, on flight 511, the 28

  1. Isochoric Implosions for Fast Ignition

    International Nuclear Information System (INIS)

    Clark, D S; Tabak, M

    2007-01-01

    Various gain models have shown the potentially great advantages of Fast Ignition (FI) Inertial Confinement Fusion (ICF) over its conventional hot spot ignition counterpart [e.g., S. Atzeni, Phys. Plasmas 6, 3316 (1999); M. Tabak et al., Fusion Sci. and Technology 49, 254 (2006)]. These gain models, however, all assume nearly uniform-density fuel assemblies. In contrast, conventional ICF implosions yield hollowed fuel assemblies with a high-density shell of fuel surrounding a low-density, high-pressure hot spot. Hence, to realize fully the advantages of FI, an alternative implosion design must be found which yields nearly isochoric fuel assemblies without substantial hot spots. Here, it is shown that a self-similar spherical implosion of the type originally studied by Guderley [Luftfahrtforschung 19, 302 (1942)] may be employed to yield precisely such quasi-isochoric imploded states. The difficulty remains, however, of accessing these self-similarly imploding configurations from initial conditions representing an actual ICF target, namely a uniform, solid-density shell at rest. Furthermore, these specialized implosions must be realized for practicable drive parameters and at the scales and energies of interest in ICF. A direct-drive implosion scheme is presented which meets all of these requirements and reaches a nearly isochoric assembled density of 300 g=cm 3 and areal density of 2.4 g=cm 2 using 485 kJ of laser energy

  2. Laser-assisted homogeneous charge ignition in a constant volume combustion chamber

    Science.gov (United States)

    Srivastava, Dhananjay Kumar; Weinrotter, Martin; Kofler, Henrich; Agarwal, Avinash Kumar; Wintner, Ernst

    2009-06-01

    Homogeneous charge compression ignition (HCCI) is a very promising future combustion concept for internal combustion engines. There are several technical difficulties associated with this concept, and precisely controlling the start of auto-ignition is the most prominent of them. In this paper, a novel concept to control the start of auto-ignition is presented. The concept is based on the fact that most HCCI engines are operated with high exhaust gas recirculation (EGR) rates in order to slow-down the fast combustion processes. Recirculated exhaust gas contains combustion products including moisture, which has a relative peak of the absorption coefficient around 3 μm. These water molecules absorb the incident erbium laser radiations ( λ=2.79 μm) and get heated up to expedite ignition. In the present experimental work, auto-ignition conditions are locally attained in an experimental constant volume combustion chamber under simulated EGR conditions. Taking advantage of this feature, the time when the mixture is thought to "auto-ignite" could be adjusted/controlled by the laser pulse width optimisation, followed by its resonant absorption by water molecules present in recirculated exhaust gas.

  3. What is taking place in science classrooms?: A case study analysis of teaching and learning in seventh-grade science of one Alabama school and its impact on African American student learning

    Science.gov (United States)

    Norman, Lashaunda Renea

    This qualitative case study investigated the teaching strategies that improve science learning of African American students. This research study further sought the extent the identified teaching strategies that are used to improve African American science learning reflect culturally responsive teaching. Best teaching strategies and culturally responsive teaching have been researched, but there has been minimal research on the impact that both have on science learning, with an emphasis on the African American population. Consequently, the Black-White achievement gap in science persists. The findings revealed the following teaching strategies have a positive impact on African American science learning: (a) lecture-discussion, (b) notetaking, (c) reading strategies, (d) graphic organizers, (e) hands-on activities, (f) laboratory experiences, and (g) cooperative learning. Culturally responsive teaching strategies were evident in the seventh-grade science classrooms observed. Seven themes emerged from this research data: (1) The participating teachers based their research-based teaching strategies used in the classroom on all of the students' learning styles, abilities, attitudes towards science, and motivational levels about learning science, with no emphasis on the African American student population; (2) The participating teachers taught the state content standards simultaneously using the same instructional model daily, incorporating other content areas when possible; (3) The participating African American students believed their seventh-grade science teachers used a variety of teaching strategies to ensure science learning took place, that science learning was fun, and that science learning was engaging; (4) The participating African American students genuinely liked their teacher; (5) The participating African American students revealed high self-efficacy; (6) The African American student participants' parents value education and moved to Success Middle School

  4. Ignition of a Droplet of Composite Liquid Fuel in a Vortex Combustion Chamber

    Science.gov (United States)

    Valiullin, T. R.; Vershinina, K. Yu; Glushkov, D. O.; Strizhak, P. A.

    2017-11-01

    Experimental study results of a droplet ignition and combustion were obtained for coal-water slurry containing petrochemicals (CWSP) prepared from coal processing waste, low-grade coal and waste petroleum products. A comparative analysis of process characteristics were carried out in different conditions of fuel droplet interaction with heated air flow: droplet soars in air flow in a vortex combustion chamber, droplet soars in ascending air flow in a cone-shaped combustion chamber, and droplet is placed in a thermocouple junction and motionless in air flow. The size (initial radii) of CWSP droplet was varied in the range of 0.5-1.5 mm. The ignition delay time of fuel was determined by the intensity of the visible glow in the vicinity of the droplet during CWSP combustion. It was established (under similar conditions) that ignition delay time of CWSP droplets in the combustion chamber is lower in 2-3.5 times than similar characteristic in conditions of motionless droplet placed in a thermocouple junction. The average value of ignition delay time of CWSP droplet is 3-12 s in conditions of oxidizer temperature is 600-850 K. Obtained experimental results were explained by the influence of heat and mass transfer processes in the droplet vicinity on ignition characteristics in different conditions of CWSP droplet interaction with heated air flow. Experimental results are of interest for the development of combustion technology of promising fuel for thermal power engineering.

  5. Take heart!

    CERN Multimedia

    Alizée Dauvergne

    2010-01-01

    Recently, ten new semi-automatic defibrillators were installed at various locations around CERN. This is a preventive measure intended to provide cardiac arrest victims with the best possible response. The first responder could be you!   The Director-General has welcomed the initiative of the Medical Service and Fire Brigade for the installation of ten new semi-automatic defibrillators. You have probably seen them on your way to the restaurant, for example:  brand new semi-automatic defibrillators, ready for an emergency. Housed in a white wall-mounted case, the bright red defibrillators are marked with a white heart symbol crossed by a lightning bolt (see photo). The defibrillator is designed so that anyone can use it. “Anyone can use it, you don’t need to be a health professional,” says Dr Reymond from CERN's Medical Service. Together with the CERN Fire Brigade, he is behind the initiative to have these units put in place. And with good reason, as the unit...

  6. Taking Leave?

    CERN Multimedia

    2000-01-01

    Planning a holiday? Then if you're a member of the personnel, you'll need to use the Laboratory's new leave system that will be put in place on 1 October. Leave allocations don't change - you are entitled to just as much holiday as before - but instead of being credited annually, your leave will be credited on a monthly basis, and this information will be communicated on your salary slip. The reason for the change is that with the various new leave schemes such as Recruitment by Saved Leave (RSL) and the Progressive Retirement Programme (PRP), a streamlined procedure was required for dealing with all kinds of leave. In the new system, each member of the personnel will have leave accounts to which leave will be credited monthly from the payroll and debited each time an absence is registered in the CERN Electronic Document Handling system (EDH). Leave balances will appear on monthly pay slips, and full details of leave transactions and balances will be available through EDH at all times. As the leave will be c...

  7. National Ignition Facility site requirements

    International Nuclear Information System (INIS)

    1996-07-01

    The Site Requirements (SR) provide bases for identification of candidate host sites for the National Ignition Facility (NIF) and for the generation of data regarding potential actual locations for the facilities. The SR supplements the NIF Functional Requirements (FR) with information needed for preparation of responses to queries for input to HQ DOE site evaluation. The queries are to include both documents and explicit requirements for the potential host site responses. The Sr includes information extracted from the NIF FR (for convenience), data based on design approaches, and needs for physical and organization infrastructure for a fully operational NIF. The FR and SR describe requirements that may require new construction or may be met by use or modification of existing facilities. The SR do not establish requirements for NIF design or construction project planning. The SR document does not constitute an element of the NIF technical baseline

  8. Definition of Ignition in Inertial Confinement Fusion

    Science.gov (United States)

    Christopherson, A. R.; Betti, R.

    2017-10-01

    Defining ignition in inertial confinement fusion (ICF) is an unresolved problem. In ICF, a distinction must be made between the ignition of the hot spot and the propagation of the burn wave in the surrounding dense fuel. Burn propagation requires that the hot spot is robustly ignited and the dense shell exhibits enough areal density. Since most of the energy gain comes from burning the dense shell, in a scale of increasing yields, hot-spot ignition comes before high gains. Identifying this transition from hot-spot ignition to burn-wave propagation is key to defining ignition in general terms applicable to all fusion approaches that use solid DT fuel. Ad hoc definitions such as gain = 1 or doubling the temperature are not generally valid. In this work, we show that it is possible to identify the onset of ignition through a unique value of the yield amplification defined as the ratio of the fusion yield including alpha-particle deposition to the fusion yield without alphas. Since the yield amplification is a function of the fractional alpha energy fα =EαEα 2Ehs 2Ehs (a measurable quantity), it appears possible not only to define ignition but also to measure the onset of ignition by the experimental inference of the fractional alpha energy and yield amplification. This material is based upon work supported by the Department of Energy Office of Fusion Energy Services under Award Number DE-FC02-04ER54789 and National Nuclear Security Administration under Award Number DE-NA0001944.

  9. Approach to ignition of tokamak reactors

    International Nuclear Information System (INIS)

    Sigmar, D.J.

    1981-02-01

    Recent transport modeling results for JET, INTOR, and ETF are reviewed and analyzed with respect to existing uncertainties in the underlying physics, the self-consistency of the very large numerical codes, and the margin for ignition. The codes show ignition to occur in ETF/INTOR-sized machines if empirical scaling can be extrapolated to ion temperatures (and beta values) much higher than those presently achieved, if there is no significant impurity accumulation over the first 7 s, and if the known ideal and resistive MHD instabilities remain controllable for the evolving plasma profiles during ignition startup

  10. Overview of the Compact Ignition Tokamak

    International Nuclear Information System (INIS)

    Flanagan, C.A.

    1986-01-01

    The mission of CIT is to realize, study, and optimize fully ignited plasma discharges. The physics requirements have been established to provide reasonable assurance that the mission will be achieved: (1) plasma confinement guidelines consider all present scaling laws; ohmic, auxiliary heated L-mode, auxiliary heated H-mode, (2) figure-of-merit established: X = aB/q; this is proportional to ignition margin; X must be >25, (3) burn pulse duration set at ten times tau-E; an additional two times tau-E specified to heat to ignition, and (4) capability to operate both in limiter and divertor mode

  11. Development status of the ignition system for Vinci

    NARCIS (Netherlands)

    Frenken, G.; Vermeulen, E.; Bouquet, F.; Sanders, H.M.

    2002-01-01

    The development status of ignition system for the new cryogenic upper stage engine Vinci is presented. The concept differs from existing upper stage ignition systems as its functioning is engine independent. The system consists of a spark torch igniter, a highpressure igniter feed system and an

  12. National Ignition Facility Cryogenic Target Systems Interim Management Plan

    International Nuclear Information System (INIS)

    Warner, B

    2002-01-01

    Restricted availability of funding has had an adverse impact, unforeseen at the time of the original decision to projectize the National Ignition Facility (NIF) Cryogenic Target Handling Systems (NCTS) Program, on the planning and initiation of these efforts. The purpose of this document is to provide an interim project management plan describing the organizational structure and management processes currently in place for NCTS. Preparation of a Program Execution Plan (PEP) for NCTS has been initiated, and a current draft is provided as Attachment 1 to this document. The National Ignition Facility is a multi-megajoule laser facility being constructed at Lawrence Livermore National Laboratory (LLNL) by the National Nuclear Security Administration (NNSA) in the Department of Energy (DOE). Its primary mission is to support the Stockpile Stewardship Program (SSP) by performing experiments studying weapons physics, including fusion ignition. NIF also supports the missions of weapons effects, inertial fusion energy, and basic science in high-energy-density physics. NIF will be operated by LLNL under contract to the University of California (UC) as a national user facility. NIF is a low-hazard, radiological facility, and its operation will meet all applicable federal, state, and local Environmental Safety and Health (ES and H) requirements. The NCTS Interim Management Plan provides a summary of primary design criteria and functional requirements, current organizational structure, tracking and reporting procedures, and current planning estimates of project scope, cost, and schedule. The NIF Director controls the NIF Cryogenic Target Systems Interim Management Plan. Overall scope content and execution schedules for the High Energy Density Physics Campaign (SSP Campaign 10) are currently undergoing rebaselining and will be brought into alignment with resources expected to be available throughout the NNSA Future Years National Security Plan (FYNSP). The revised schedule for

  13. A comparative experimental study on engine operating on premixed charge compression ignition and compression ignition mode

    Directory of Open Access Journals (Sweden)

    Bhiogade Girish E.

    2017-01-01

    Full Text Available New combustion concepts have been recently developed with the purpose to tackle the problem of high emissions level of traditional direct injection Diesel engines. A good example is the premixed charge compression ignition combustion. A strategy in which early injection is used causing a burning process in which the fuel burns in the premixed condition. In compression ignition engines, soot (particulate matter and NOx emissions are an extremely unsolved issue. Premixed charge compression ignition is one of the most promising solutions that combine the advantages of both spark ignition and compression ignition combustion modes. It gives thermal efficiency close to the compression ignition engines and resolves the associated issues of high NOx and particulate matter, simultaneously. Premixing of air and fuel preparation is the challenging part to achieve premixed charge compression ignition combustion. In the present experimental study a diesel vaporizer is used to achieve premixed charge compression ignition combustion. A vaporized diesel fuel was mixed with the air to form premixed charge and inducted into the cylinder during the intake stroke. Low diesel volatility remains the main obstacle in preparing premixed air-fuel mixture. Exhaust gas re-circulation can be used to control the rate of heat release. The objective of this study is to reduce exhaust emission levels with maintaining thermal efficiency close to compression ignition engine.

  14. I could never take the place of your man

    DEFF Research Database (Denmark)

    Andersen, Poul Houman; Munksgaard, Kristin B.

    We explore the dynamic tensions between the strategic change intentions by business actors and the rigidities of routines in business networks. We capture strategic change acts using the recent advances in the literature on network pictures as way to understand the value creation logics of managers...... and we coin the term network picturing to describe this process. We develop a theoretical framework that links network pictures and the patterned processes of interaction in business network routines. Here, we argue that the resistance managers' meet in their change efforts is likely, even if the change...... efforts do not directly rival or contradict that of other actors in the exchange party in a resource-dependency sense, but may be caused simply by disrupting the existing business network. We use three case studies to illustrate and further explore the tensions between network picturing and network...

  15. How Does Photosynthesis Take Place in Our Oceans?

    OpenAIRE

    Ghosh, Tonmoy; Mishra, Sandhya

    2017-01-01

    The food we eat ultimately comes from plants, either directly or indirectly. The importance of plants as the global kitchen can never be underestimated. Plants “eat” sunlight and carbon dioxide to produce their own food and food for the millions of other organisms dependent on them. A molecule, chlorophyll (Chl), is crucial for this process, since it absorbs sunlight. However, the way land plants produce their food is very different from the way plants in the oceans produce their food. Since ...

  16. When radionuclides take the place of vital elements

    International Nuclear Information System (INIS)

    Rouffignac, Ch. de; Poncy, J.L.; Martin, M.

    2003-01-01

    The radiosensitivity of the kidneys is a major factor restricting the applications of chemoradiotherapy. However, improved knowledge of the mechanisms involved has allowed new treatments to be developed that attenuate the effects of the irradiation or delay its consequences. Certain radioactive elements can behave in the body like calcium, and so exhibit a special affinity for bone structures. The skin is the first tissue that is damaged by external exposure to ionising radiation. The early and late responses to irradiation in this complex organ are still poorly understood. Thanks to DNA micro-arrays, the response of skin cells to irradiation, and in particular that of epidermal stem cells, can now be studied globally. (authors)

  17. Does the measurement take place when nobody observes it

    Energy Technology Data Exchange (ETDEWEB)

    Gurvitz, Shmuel [Department of Particle Physics and Astrophysics, Weizmann Institute of Science, Rehovot (Israel); Beijing Computational Science Research Center, Beijing (China)

    2017-06-15

    We consider non-selective continuous measurements of a particle tunneling to a reservoir of finite band-width (Λ). The particle is continuously monitored by frequent projective measurements (''quantum trajectory''), separated by a time-interval τ. A simple analytical expression for the decay rate has been obtained. For Markovian reservoirs (Λ → ∞), no effect of the measurements is found. Otherwise for a finite Λ, the decay rate always depends on the measurement time τ. This result is compared with alternative calculations, with no intermediate measurements, but when the measurement device is included in the Schroedinger evolution. We found that the detector affects the system by the decoherence rate (Γ{sub d}), related to the detector's signal. Although both treatments are different, the final results become very close for τ = 2/Γ{sub d}. This τ corresponds to the minimal time for which the detector's signal can be distinguished by an ''observer''. This indicates a fundamental role of information in quantum motion and can be used for the extension of the quantum trajectory method for non-Markovian environments. (copyright 2016 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  18. BP-Mobil partnership. The common network takes place

    International Nuclear Information System (INIS)

    Anon.

    1997-01-01

    After the partnership between BP and Mobil was signed, the program of transformation of the petrol stations network started in November 1996 in the UK and concern 3300 stations in Europe and 800 stations in France. About 9100 stations will be transformed by the end of 1998. BP France is the operator for petroleum products (petrol, fuel, bitumens, LPG..) with a 70% share holding (30% for Mobil) while Mobil is the major shareholder (51%) for the lubricants and special products activities. The chemical, aviation nd maritime activities are not concerned. Thanks to the fusion of their down-file activities in Europe, the benefits of the partnership should reach 600 to 700 million of US Dollars each year. However the restructuring cost should reach 740 millions of US Dollars in two years, which doubles the initial estimation. Short paper. (J.S.)

  19. Ignition in Convective-Diffusive Systems

    National Research Council Canada - National Science Library

    Law, Chung

    1999-01-01

    ... efficiency as well as the knock and emission characteristics. The ignition event is clearly controlled by the chemical reactions of fuel oxidation and the fluid mechanics of convective and diffusive transport...

  20. Ignition properties of nuclear grade activated carbons

    International Nuclear Information System (INIS)

    Freeman, W.P.; Hunt, J.R.; Kovach, J.L.

    1983-01-01

    The ignition property of new activated carbons used in air cleaning systems of nuclear facilities has been evaluated in the past, however very little information has been generated on the behavior of aged, weathered carbons which have been exposed to normal nuclear facility environment. Additionally the standard procedure for evaluation of ignition temperature of carbon is performed under very different conditions than those used in the design of nuclear air cleaning systems. Data were generated evaluating the ageing of activated carbons and comparing their CH 3 131 I removal histories to their ignition temperatures. A series of tests were performed on samples from one nuclear power reactor versus use time, a second series evaluated samples from several plants showing the variability of atmospheric effects. The ignition temperatures were evaluated simulating the conditions existing in nuclear air cleaning systems, such as velocity, bed depth, etc., to eliminate potential confusion resulting from artifically set current standard conditions

  1. Plasma igniter for internal-combustion engines

    Science.gov (United States)

    Breshears, R. R.; Fitzgerald, D. J.

    1978-01-01

    Hot ionized gas (plasma) ignites air/fuel mixture in internal combustion engines more effectively than spark. Electromagnetic forces propel plasma into combustion zone. Combustion rate is not limited by flame-front speed.

  2. Perspective Taking in Workplaces

    Directory of Open Access Journals (Sweden)

    Zappalà Salvatore

    2014-07-01

    Full Text Available Workplaces are often described as places in which individuals are motivated by their self-interests and in which negative events like time pressure, anxiety, conflict with co-workers, miscomprehensions, difficulties in solving problems, not-transmitted or not-exchanged information that lead to mistakes, and in some cases to injuries, stress or control, are part of everyday life (Dormann & Zapf, 2002; Schabracq, Winnubst and Cooper, 2003. Such situations are often the result of the limited comprehension of needs, skills, or information available to colleagues, supervisors, subordinates, clients or providers. However, workplaces are also places in which employees take care of clients, support colleagues and subordinates (Rhoades & Eisenberger, 2002, are enthusiastic about their job (Bakker et al., 2008, are motivated by leaders that encourage employees to transcend their own self-interests for the good of the group or the organization and provide them with the confidence to perform beyond expectations (Bass, 1997. Thus positive relationships at work are becoming a new interdisciplinary domain of inquiry (Dutton & Ragins, 2006. Within this positive relationships framework, in this paper we focus on a positive component of workplaces, and particularly on an individual cognitive and emotional process that has an important role in the workplace because it facilitates interpersonal relations and communications: it is the perspective taking process. In order to describe perspective taking, we will refer to some empirical studies and particularly to the review published by Parker, Atkins and Axtell in 2008 on the International Review of Industrial and Organizational Psychology.

  3. Test plan for core drilling ignitability testing

    International Nuclear Information System (INIS)

    Witwer, K.S.

    1996-01-01

    The objective of this testing is to determine if ignition occurs while core drilling in a flammable gas environment. Drilling parameters are chosen so as to provide bounding conditions for the core sampling environment. If ignition does not occur under the conditions set forth in this test, then a satisfactory level of confidence will be obtained which would allow field operations under the normal drilling conditions

  4. Dynamic Regime of Ignition of Solid Propellant

    Directory of Open Access Journals (Sweden)

    Zolotorev Nikolay

    2016-01-01

    Full Text Available This article presents a dynamic regime of exposure of the radiant flux on the sample of gun-cotton. Obtained time the ignition of gun-cotton in the heating conditions of increasing heat flux in the range from 0.2 W/cm2 to 22 W/cm2. A comparison of the delay times of the ignition when heated variable and constant heat flux.

  5. The National Ignition Facility Project. Revision 1

    International Nuclear Information System (INIS)

    Paisner, J.A.; Campbell, E.M.; Hogan, W.J.

    1994-01-01

    The mission of the National Ignition Facility is to achieve ignition and gain in inertial confinement fusion targets in the laboratory. The facility will be used for defense applications such as weapons physics and weapons effects testing, and for civilian applications such as fusion energy development and fundamental studies of matter at high temperatures and densities. This paper reviews the design, schedule, and costs associated with the construction project

  6. Confinement scaling and ignition in tokamaks

    International Nuclear Information System (INIS)

    Perkins, F.W.; Sun, Y.C.

    1985-10-01

    A drift wave turbulence model is used to compute the scaling and magnitude of central electron temperature and confinement time of tokamak plasmas. The results are in accord with experiment. Application to ignition experiments shows that high density (1 to 2) . 10 15 cm -3 , high field, B/sub T/ > 10 T, but low temperature T approx. 6 keV constitute the optimum path to ignition

  7. Physics parameter space of tokamak ignition devices

    International Nuclear Information System (INIS)

    Selcow, E.C.; Peng, Y.K.M.; Uckan, N.A.; Houlberg, W.A.

    1985-01-01

    This paper describes the results of a study to explore the physics parameter space of tokamak ignition experiments. A new physics systems code has been developed to perform the study. This code performs a global plasma analysis using steady-state, two-fluid, energy-transport models. In this paper, we discuss the models used in the code and their application to the analysis of compact ignition experiments. 8 refs., 8 figs., 1 tab

  8. Plasma transport in a compact ignition tokamak

    International Nuclear Information System (INIS)

    Singer, C.E.; Ku, L.P; Bateman, G.

    1987-02-01

    Nominal predicted plasma conditions in a compact ignition tokamak are illustrated by transport simulations using experimentally calibrated plasma transport models. The range of uncertainty in these predictions is explored by using various models which have given almost equally good fits to experimental data. Using a transport model which best fits the data, thermonuclear ignition occurs in a Compact Ignition Tokamak design with major radius 1.32 m, plasma half-width 0.43 m, elongation 2.0, and toroidal field and plasma current ramped in six seconds from 1.7 to 10.4 T and 0.7 to 10 MA, respectively. Ignition is facilitated by 20 MW of heating deposited off the magnetic axis near the 3 He minority cyclotron resonance layer. Under these conditions, sawtooth oscillations are small and have little impact on ignition. Tritium inventory is minimized by preconditioning most discharges with deuterium. Tritium is injected, in large frozen pellets, only after minority resonance preheating. Variations of the transport model, impurity influx, heating profile, and pellet ablation rates, have a large effect on ignition and on the maximum beta that can be achieved

  9. Does charge transfer correlate with ignition probability?

    International Nuclear Information System (INIS)

    Holdstock, Paul

    2008-01-01

    Flammable or explosive atmospheres exist in many industrial environments. The risk of ignition caused by electrostatic discharges is very real and there has been extensive study of the incendiary nature of sparks and brush discharges. It is clear that in order to ignite a gas, an amount of energy needs to be delivered to a certain volume of gas within a comparatively short time. It is difficult to measure the energy released in an electrostatic discharge directly, but it is possible to approximate the energy in a spark generated from a well defined electrical circuit. The spark energy required to ignite a gas, vapour or dust cloud can be determined by passing such sparks through them. There is a relationship between energy and charge in a capacitive circuit and so it is possible to predict whether or not a spark discharge will cause an ignition by measuring the charge transferred in the spark. Brush discharges are in many ways less well defined than sparks. Nevertheless, some work has been done that has established a relationship between charge transferred in brush discharges and the probability of igniting a flammable atmosphere. The question posed by this paper concerns whether such a relationship holds true in all circumstances and if there is a universal correlation between charge transfer and ignition probability. Data is presented on discharges from textile materials that go some way to answering this question.

  10. TOPICAL REVIEW: Plasma assisted ignition and combustion

    Science.gov (United States)

    Starikovskaia, S. M.

    2006-08-01

    In recent decades particular interest in applications of nonequilibrium plasma for the problems of plasma-assisted ignition and plasma-assisted combustion has been observed. A great amount of experimental data has been accumulated during this period which provided the grounds for using low temperature plasma of nonequilibrium gas discharges for a number of applications at conditions of high speed flows and also at conditions similar to automotive engines. The paper is aimed at reviewing the data obtained and discusses their treatment. Basic possibilities of low temperature plasma to ignite gas mixtures are evaluated and historical references highlighting pioneering works in the area are presented. The first part of the review discusses plasmas applied to plasma-assisted ignition and combustion. The paper pays special attention to experimental and theoretical analysis of some plasma parameters, such as reduced electric field, electron density and energy branching for different gas discharges. Streamers, pulsed nanosecond discharges, dielectric barrier discharges, radio frequency discharges and atmospheric pressure glow discharges are considered. The second part depicts applications of discharges to reduce the ignition delay time of combustible mixtures, to ignite transonic and supersonic flows, to intensify ignition and to sustain combustion of lean mixtures. The results obtained by different authors are cited, and ways of numerical modelling are discussed. Finally, the paper draws some conclusions on the main achievements and prospects of future investigations in the field.

  11. Numerical research of heat and mass transfer during low-temperature ignition of a coal particle

    Directory of Open Access Journals (Sweden)

    Glushkov Dmitrii O.

    2015-01-01

    Full Text Available Numerical researches have been carried out to study the influence of air flow temperature and a fossil fuel particle rate on sufficient conditions of ignition in a “coal particle - air” system. Developed mathematical model takes into account interconnected processes of heat transfer in a coal particle and gas area, thermal decomposition of organic material, diffusion and gas-phase oxidation of volatiles, heating of a coke (carbon and its heterogeneous ignition. The effect of low-temperature (about 600 K ignition for a single coal particle is impossible even at variation of its rate (radius from 0.05 mm to 0.5 mm. Nevertheless this process is possible for group of particles (two, three, et al. situated at close-range from each other. The physical aspects of the problem are discussed.

  12. Reaction-in-flight neutrons as a signature for shell mixing in National Ignition Facility capsules

    International Nuclear Information System (INIS)

    Hayes, A. C.; Bradley, P. A.; Grim, G. P.; Jungman, Gerard; Wilhelmy, J. B.

    2010-01-01

    Analytic calculations and results from computational simulations are presented that suggest that reaction-in-flight (RIF) neutrons can be used to diagnose mixing of the ablator shell material into the fuel in deuterium-tritium (DT) capsules designed for the National Ignition Facility (NIF) [J. A. Paisner, J. D. Boyes, S. A. Kumpan, W. H. Lowdermilk, and M. S. Sorem, Laser Focus World 30, 75 (1994)]. Such mixing processes in NIF capsules are of fundamental physical interest and can have important effects on capsule performance, quenching the total thermonuclear yield. The sensitivity of RIF neutrons to hydrodynamical mixing arises through the dependence of RIF production on charged-particle stopping lengths in the mixture of DT fuel and ablator material. Since the stopping power in the plasma is a sensitive function of the electron temperature and density, it is also sensitive to mix. RIF production scales approximately inversely with the degree of mixing taking place, and the ratio of RIF to down-scattered neutrons provides a measure of the mix fraction and/or the mixing length. For sufficiently high-yield capsules, where spatially resolved RIF images may be possible, neutron imaging could be used to map RIF images into detailed mix images.

  13. Ignition delay times of Gasoline Distillation Cuts measured with Ignition Quality Tester

    KAUST Repository

    Naser, Nimal

    2017-04-21

    Tailoring fuel properties to maximize the efficiency of internal combustion engines is a way towards achieving cleaner combustion systems. In this work, the ignition properties of various gasoline fuel distillation cuts are analyzed to better understand fuel properties of the full boiling range fuel. An advanced distillation column (ADC) provides a more realistic representation of volatility characteristics, which can be modeled using equilibrium thermodynamic methods. The temperature reported is that of the liquid, as opposed to the vapor temperature in conventional ASTM D86 distillation standard. Various FACE (fuels for advanced combustion engines) gasolines were distilled and various cuts were obtained. The separated fractions were then tested in an ignition quality tester (IQT) to see the effect of chemical composition of different fractions on their ignition delay time. Fuels with lower aromatic content showed decreasing ignition delay time with increasing boiling point (i.e., molecular weight). However, fuels with higher aromatic content showed an initial decrease in ignition delay time with increasing boiling point, followed by drastic increase in ignition delay time due to fractions containing aromatics. This study also provides an understanding on contribution of different fractions to the ignition delay time of the fuel, which provides insights into fuel stratification utilized in gasoline compression ignition (GCI) engines to tailor heat release rates.

  14. Recent progress in ignition fusion research on the National Ignition Facility

    International Nuclear Information System (INIS)

    Leeper, Ramon J.

    2011-01-01

    This paper will review the ignition fusion research program that is currently being carried out on the National Ignition Facility (NIF) located at Lawrence Livermore National Laboratory. This work is being conducted under the auspices of the National Ignition Campaign (NIC) that is a broad collaboration of national laboratories and universities that together have developed a detailed research plan whose goal is ignition in the laboratory. The paper will begin with a description of the NIF facility and associated experimental facilities. The paper will then focus on the ignition target and hohlraum designs that will be tested in the first ignition attempts on NIF. The next topic to be introduced will be a description of the diagnostic suite that has been developed for the initial ignition experiments on NIF. The paper will then describe the experimental results that were obtained in experiments conducted during the fall of 2009 on NIF. Finally, the paper will end with a description of the detailed experimental plans that have been developed for the first ignition campaign that will begin later this year. (author)

  15. On the possibility of D-3He fusion based on fast - ignition inertial confinement scheme

    International Nuclear Information System (INIS)

    Nakao, Y.; Hegi, K.; Ohmura, T.; Katsube, M.; Kudo, K.; Johzaki, T.; Ohta, M.

    2007-01-01

    Although nuclear fusion reactors adopting D 3 He fuel could provide many advantages, such as low neutron generation and efficient conversion of output fusion energy, the achievement of ignition is a difficult problem. It is therefore of particular importance to find some methods or schemes that relax the ignition requirements. In inertial confinement scheme, the use of pure D 3 He fuel is impractical because of the excessive requirement on driver energy. A small amount of DT fuel as 'igniter' is hence indispensable [1]. Our previous burn simulation [1] for DT/D 3 He fuels compressed to 5000 times the liquid density showed that substantial fuel gains (∼500) are obtained from fuels having parameters ρ R D T = 3 g/cm 2 , ρ R t otal 14 g/cm 2 and a central spark temperature of 5 keV. The driver energy needed to achieve these gains is estimated to be ∼30 MJ when the coupling efficiency is 10%; in this case the target gain is ∼50. Subsequent implosion simulation [2], however, showed that after void closure the central DT fuel is ignited while the bulk of the main D 3 He fuel is still imploding with high velocities. This pre-ignition of DT fuel leads to a low compression of the main fuel and prevents the DT/D 3 He fuel from obtaining required gain. These difficulties associated with the pre-ignition of DT fuel could be resolved or mitigated if other ignition schemes such as fast-ignition [3] and/or impact-ignition [4] are adopted, because in these schemes compression and ignition phases are separated. Furthermore, the reduction of driver energy can be expected. In the present study, we examine the possibility of D 3 He fusion in the fast-ignition scheme. Simulations until now have been made for a DT/D 3 He fuel compressed to 5000 times the liquid density by using FIBMET (2D fusion ignition and burning code) [5] and a newly developed neutron diffusion code. DT igniter was assumed to be placed at a corner of the compressed fuel. The ρ R values and temperature of

  16. Antiproton fast ignition for inertial confinement fusion

    International Nuclear Information System (INIS)

    Perkins, L.J.

    1999-01-01

    With 180 MJ/microg, antiprotons offer the highest stored energy per unit mass of any known entity. The use of antiprotons to promote fast ignition in an inertial confinement fusion (ICF) capsule and produce high target gains with only modest compression of the main fuel is investigated. Unlike standard fast ignition where the ignition energy is supplied by energetic, short pulse laser, the energy here is supplied through the ionization energy deposited when antiprotons annihilate at the center of a compressed fuel capsule. This can be considered in-situ fast ignition as it obviates the need for the external injection of the ignition energy. In the first of two candidate schemes, the antiproton package is delivered by a low-energy ion beam. In the second, autocatalytic scheme, the antiprotons are preemplaced at the center of the capsule prior to compression. In both schemes, the author estimates that ∼10 12 antiprotons are required to initiate fast ignition in a typical ICF capsule and show that incorporation of a thin, heavy metal shell is desirable to enhance energy deposition within the ignitor zone. In addition to eliminating the need for a second, energetic fast laser and vulnerable final optics, this scheme would achieve central ignition without reliance on laser channeling through halo plasma or Hohlraum debris. However, in addition to the practical difficulties of storage and manipulation of antiprotons at low energy, the other large uncertainty for the practicality of such a speculative scheme is the ultimate efficiency of antiproton production in an external, optimized facility. Estimates suggest that the electrical wall plug energy per pulse required for the separate production of the antiprotons is of the same order as that required for the conventional slow compression driver

  17. Ignition parameters and early flame kernel development of laser-ignited combustible gas mixtures

    International Nuclear Information System (INIS)

    Kopecek, H.; Wintner, E.; Ruedisser, D.; Iskra, K.; Neger, T.

    2002-01-01

    Full text: Laser induced breakdown of focused pulsed laser radiation, the subsequent plasma formation and thermalization offers a possibility of ignition of combustible gas mixtures free from electrode interferences, an arbitrary choice of the location within the medium and exact timing regardless of the degree of turbulence. The development and the decreasing costs of solid state laser technologies approach the pay-off for the higher complexity of such an ignition system due to several features unique to laser ignition. The feasability of laser ignition was demonstrated in an 1.5 MW(?) natural gas engine, and several investigations were performed to determine optimal ignition energies, focus shapes and laser wavelengths. The early flame kernel development was investigated by time resolved planar laser induced fluorescence of the OH-radical which occurs predominantly in the flame front. The flame front propagation showed typical features like toroidal initial flame development, flame front return and highly increased flame speed along the laser focus axis. (author)

  18. 3rd Conference on Ignition Systems for Gasoline Engines

    CERN Document Server

    Sens, Marc

    2017-01-01

    The volume includes selected and reviewed papers from the 3rd Conference on Ignition Systems for Gasoline Engines in Berlin in November 2016. Experts from industry and universities discuss in their papers the challenges to ignition systems in providing reliable, precise ignition in the light of a wide spread in mixture quality, high exhaust gas recirculation rates and high cylinder pressures. Classic spark plug ignition as well as alternative ignition systems are assessed, the ignition system being one of the key technologies to further optimizing the gasoline engine.

  19. Ion beam heating for fast ignition

    International Nuclear Information System (INIS)

    Gus'kov, S.Yu.; Limpouch, J.; Klimo, O.

    2010-01-01

    Complete text of publication follows. The characteristics features of the formation of the spatial distribution of the energy transferred to the plasma from a beam of ions with different initial energies, masses and charges under fast ignition conditions are determined. The motion of the Bragg peak is extended with respect to the spatial distribution of the temperature of the ion-beam-heated medium. The parameters of the ion beams are determined to initiate different regimes of fast ignition of thermonuclear fuel precompressed to a density of 300-500 g/cm 3 - the edge regime, in which the ignition region is formed at the outer boundary of the fuel, and the internal regime, in which the ignition region is formed in central parts of the fuel. The conclusion on the requirements for fast ignition by light and heavy ion beams is presented. It is shown that the edge heating with negative temperature gradient is described by a self-similar solution. Such a temperature distribution is the reason of the fact that the ignited beam energy at the edge heating is larger than the minimal ignition energy by factor 1.65. The temperature Bragg peak may be produced by ion beam heating in the reactor scale targets with pR-parameter larger than 3-4 g/cm 2 . In particular, for central ignition of the targets with pR-parameters in the range of 4-8 g/cm 2 the ion beam energy should be, respectively, from 5 to 7 times larger than the minimal ignition energy. The work by S.Ye. Gus'kov, D.V. Il'in, and V.E. Sherman was supported by the Ministry of Education and Science of the Russian Federation under the program 'Development of the Scientific Potential of High Education for 2009-2010' (project no. 2.1.1/1505) and the Russian Foundation for Basic Research (project no. 08-02-01394 a ). The work by J. Limpouch and O. Klimo was supported by the Czech Ministry of Education (project no. LC528, MSM6840770022).

  20. Dark Matter Ignition of Type Ia Supernovae.

    Science.gov (United States)

    Bramante, Joseph

    2015-10-02

    Recent studies of low redshift type Ia supernovae (SN Ia) indicate that half explode from less than Chandrasekhar mass white dwarfs, implying ignition must proceed from something besides the canonical criticality of Chandrasekhar mass SN Ia progenitors. We show that 1-100 PeV mass asymmetric dark matter, with imminently detectable nucleon scattering interactions, can accumulate to the point of self-gravitation in a white dwarf and collapse, shedding gravitational potential energy by scattering off nuclei, thereby heating the white dwarf and igniting the flame front that precedes SN Ia. We combine data on SN Ia masses with data on the ages of SN Ia-adjacent stars. This combination reveals a 2.8σ inverse correlation between SN Ia masses and ignition ages, which could result from increased capture of dark matter in 1.4 vs 1.1 solar mass white dwarfs. Future studies of SN Ia in galactic centers will provide additional tests of dark-matter-induced type Ia ignition. Remarkably, both bosonic and fermionic SN Ia-igniting dark matter also resolve the missing pulsar problem by forming black holes in ≳10  Myr old pulsars at the center of the Milky Way.

  1. Low power arcjet thruster pulse ignition

    Science.gov (United States)

    Sarmiento, Charles J.; Gruber, Robert P.

    1987-01-01

    An investigation of the pulse ignition characteristics of a 1 kW class arcjet using an inductive energy storage pulse generator with a pulse width modulated power converter identified several thruster and pulse generator parameters that influence breakdown voltage including pulse generator rate of voltage rise. This work was conducted with an arcjet tested on hydrogen-nitrogen gas mixtures to simulate fully decomposed hydrazine. Over all ranges of thruster and pulser parameters investigated, the mean breakdown voltages varied from 1.4 to 2.7 kV. Ignition tests at elevated thruster temperatures under certain conditions revealed occasional breakdowns to thruster voltages higher than the power converter output voltage. These post breakdown discharges sometimes failed to transition to the lower voltage arc discharge mode and the thruster would not ignite. Under the same conditions, a transition to the arc mode would occur for a subsequent pulse and the thruster would ignite. An automated 11 600 cycle starting and transition to steady state test demonstrated ignition on the first pulse and required application of a second pulse only two times to initiate breakdown.

  2. Physics aspects of the Compact Ignition Tokamak

    International Nuclear Information System (INIS)

    Post, D.; Bateman, G.; Houlberg, W.

    1986-11-01

    The Compact Ignition Tokamak (CIT) is a proposed modest-size ignition experiment designed to study the physics of alpha-particle heating. The basic concept is to achieve ignition in a modest-size minimum cost experiment by using a high plasma density to achieve the condition of ntau/sub E/ ∼ 2 x 10 20 sec m -3 required for ignition. The high density requires a high toroidal field (10 T). The high toroidal field allows a large plasma current (10 MA) which improves the energy confinement, and provides a high level of ohmic heating. The present CIT design also has a gigh degree of elongation (k ∼ 1.8) to aid in producing the large plasma current. A double null poloidal divertor and a pellet injector are part of the design to provide impurity and particle control, improve the confinement, and provide flexibility for impurity and particle control, improve the confinement, and provide flexibility for improving the plasma profiles. Since auxiliary heating is expected to be necessary to achieve ignition, 10 to 20 MW of Ion Cyclotron Radio Frequency (ICRF) is to be provided

  3. Analytical model for fast-shock ignition

    International Nuclear Information System (INIS)

    Ghasemi, S. A.; Farahbod, A. H.; Sobhanian, S.

    2014-01-01

    A model and its improvements are introduced for a recently proposed approach to inertial confinement fusion, called fast-shock ignition (FSI). The analysis is based upon the gain models of fast ignition, shock ignition and considerations for the fast electrons penetration into the pre-compressed fuel to examine the formation of an effective central hot spot. Calculations of fast electrons penetration into the dense fuel show that if the initial electron kinetic energy is of the order ∼4.5 MeV, the electrons effectively reach the central part of the fuel. To evaluate more realistically the performance of FSI approach, we have used a quasi-two temperature electron energy distribution function of Strozzi (2012) and fast ignitor energy formula of Bellei (2013) that are consistent with 3D PIC simulations for different values of fast ignitor laser wavelength and coupling efficiency. The general advantages of fast-shock ignition in comparison with the shock ignition can be estimated to be better than 1.3 and it is seen that the best results can be obtained for the fuel mass around 1.5 mg, fast ignitor laser wavelength ∼0.3  micron and the shock ignitor energy weight factor about 0.25

  4. Ignition modes of nanosecond discharge with bubbles in distilled water

    International Nuclear Information System (INIS)

    Hamdan, Ahmad; Cha, Min Suk

    2015-01-01

    Here, we present the microscopic physical characteristics of nanosecond discharges with an array of bubbles in distilled water. In particular, applying a single high-voltage pulse, four delayed intensified charge-coupled device cameras successfully visualized four successive images during a single discharge event. We identified three distinctive modes of ignition inside a bubble, depending on the relative location of the bubble with respect to pin-to-hollow needle electrodes when a single bubble was located in an inter-electrode gap of 1 mm: anode-driven ignition, cathode-driven ignition, and co-ignition near both electrodes. Anode- and cathode-driven ignitions evolved into either a complete propagation of the streamer or an incomplete propagation, which were limited in location by proximity to an ignition location, while co-ignitions consistently showed complete propagation. When we increased the gap to 2 mm to accommodate multiple bubbles in the gap, an ignited bubble near the cathode was able to cause the ignition of an upper adjacent bubble. Bubble–bubble interface zones can also be spots of ignition, such that we observed simultaneous co-ignitions in the zones of bubble–bubble interfaces and near electrodes with triple bubbles. We compared the experimental results of discharge propagation with different ignition modes between Ar, He, and N 2 bubbles. In addition, numerical simulations for static electric fields reasonably supported observed ignition behavior such that field intensity was locally enhanced. (paper)

  5. Chemical Kinetics of Hydrocarbon Ignition in Practical Combustion Systems

    International Nuclear Information System (INIS)

    Westbrook, C.K.

    2000-01-01

    Chemical kinetic factors of hydrocarbon oxidation are examined in a variety of ignition problems. Ignition is related to the presence of a dominant chain branching reaction mechanism that can drive a chemical system to completion in a very short period of time. Ignition in laboratory environments is studied for problems including shock tubes and rapid compression machines. Modeling of the laboratory systems are used to develop kinetic models that can be used to analyze ignition in practical systems. Two major chain branching regimes are identified, one consisting of high temperature ignition with a chain branching reaction mechanism based on the reaction between atomic hydrogen with molecular oxygen, and the second based on an intermediate temperature thermal decomposition of hydrogen peroxide. Kinetic models are then used to describe ignition in practical combustion environments, including detonations and pulse combustors for high temperature ignition, and engine knock and diesel ignition for intermediate temperature ignition. The final example of ignition in a practical environment is homogeneous charge, compression ignition (HCCI) which is shown to be a problem dominated by the kinetics intermediate temperature hydrocarbon ignition. Model results show why high hydrocarbon and CO emissions are inevitable in HCCI combustion. The conclusion of this study is that the kinetics of hydrocarbon ignition are actually quite simple, since only one or two elementary reactions are dominant. However, there are many combustion factors that can influence these two major reactions, and these are the features that vary from one practical system to another

  6. Hot-Spot Ignition Mechanisms for Explosives and Propellants

    Science.gov (United States)

    Field, J. E.; Bourne, N. K.; Palmer, S. J. P.; Walley, S. M.

    1992-05-01

    This paper describes the response of explosives to stress and impact and in particular the mechanisms of `hot-spot' production. Samples in the form of single crystals, powder layers, pressed pellets, gels, polymer bonded explosives (PBXs) and propellants have been studied. Techniques used include a drop-weight facility with transparent anvils which allows photography at microsecond framing intervals, an instrumented drop-weight machine, a miniaturized Hopkinson bar system for high strain rate property measurement, laser speckle for studying the deformation and fracture of PBXs, an automated system for analysing speckle patterns and heat sensitive film for recording the positions and temperatures of hot spots. Polishing and staining methods have been developed to observe the microstructure of PBXs and failure during quasi-static loading. Ignition, when it occurred, took place at local hot-spot sites. Evidence is discussed for a variety of ignition mechanisms including adiabatic shear of the explosive, adiabatic heating of trapped gases during cavity collapse, viscous flow, friction, fracture and shear of added particles and triboluminescent discharge.

  7. Improving the ignition quality of fuels

    KAUST Repository

    Sarathy, Mani

    2017-06-08

    Provided herein are compounds and methods of producing compounds for improving ignition quality and combustion efficiency of fuels, for example fossil fuels. In various aspects we generate highly oxygenated compounds from hydrocarbon feedstocks. The feedstock can be a branched alkane or n-alkane having a chain length greater than or equal to 6, a cycloalkane with a 5 or 6 membered ring structure, or a alkylated cycloalkane with 5 or more carbon atoms. The reactant can be fed in the gas- phase to a partial oxidation reactor (with or without a catalyst), and at a fixed temperature, mixture composition, and residence time. The reactant can be converted to a mixture of products including keto hydroperoxides, diketo hydroperoxides, keto dihydroperoxides, hydroperoxyl cyclic ethers, and alkenyl hydroperoxides. The compounds are inherently unstable and can quickly decompose to highly reactive radical species that can be used to improve the ignition quality of a fuel and advance ignition in an engine.

  8. Progress on LMJ targets for ignition

    Energy Technology Data Exchange (ETDEWEB)

    Cherfils-Clerouin, C; Boniface, C; Bonnefille, M; Dattolo, E; Galmiche, D; Gauthier, P; Giorla, J; Laffite, S; Liberatore, S; Loiseau, P; Malinie, G; Masse, L; Masson-Laborde, P E; Monteil, M C; Poggi, F; Seytor, P; Wagon, F; Willien, J L, E-mail: catherine.cherfils@cea.f [CEA, DAM, DIF, F-91297 Arpajon (France)

    2009-12-15

    Targets designed to produce ignition on the Laser Megajoule (LMJ) are being simulated in order to set specifications for target fabrication. The LMJ experimental plans include the attempt of ignition and burn of an ICF capsule with 160 laser beams, delivering up to 1.4 MJ and 380 TW. New targets needing reduced laser energy with only a small decrease in robustness have then been designed for this purpose. Working specifically on the coupling efficiency parameter, i.e. the ratio of the energy absorbed by the capsule to the laser energy, has led to the design of a rugby-ball shaped cocktail hohlraum; with these improvements, a target based on the 240-beam A1040 capsule can be included in the 160-beam laser energy-power space. Robustness evaluations of these different targets shed light on critical points for ignition, which can trade off by tightening some specifications or by preliminary experimental and numerical tuning experiments.

  9. Progress on LMJ targets for ignition

    International Nuclear Information System (INIS)

    Cherfils-Clerouin, C; Boniface, C; Bonnefille, M; Fremerye, P; Galmiche, D; Gauthier, P; Giorla, J; Lambert, F; Laffite, S; Liberatore, S; Loiseau, P; Malinie, G; Masse, L; Masson-Laborde, P E; Monteil, M C; Poggi, F; Seytor, P; Wagon, F; Willien, J L

    2010-01-01

    Targets designed to produce ignition on the Laser MegaJoule are presented. The LMJ experimental plans include the attempt of ignition and burn of an ICF capsule with 160 laser beams, delivering up to 1.4MJ and 380TW. New targets needing reduced laser energy with only a small decrease in robustness have then been designed for this purpose. Working specifically on the coupling efficiency parameter, i.e. the ratio of the energy absorbed by the capsule to the laser energy, has led to the design of a rugby-shaped cocktail hohlraum. 1D and 2D robustness evaluations of these different targets shed light on critical points for ignition, that can be traded off by tightening some specifications or by preliminary experimental and numerical tuning experiments.

  10. Progress on LMJ targets for ignition

    Energy Technology Data Exchange (ETDEWEB)

    Cherfils-Clerouin, C; Boniface, C; Bonnefille, M; Fremerye, P; Galmiche, D; Gauthier, P; Giorla, J; Lambert, F; Laffite, S; Liberatore, S; Loiseau, P; Malinie, G; Masse, L; Masson-Laborde, P E; Monteil, M C; Poggi, F; Seytor, P; Wagon, F; Willien, J L, E-mail: catherine.cherfils@cea.f [CEA, DAM, DIF, F-91297 Arpajon (France)

    2010-08-01

    Targets designed to produce ignition on the Laser MegaJoule are presented. The LMJ experimental plans include the attempt of ignition and burn of an ICF capsule with 160 laser beams, delivering up to 1.4MJ and 380TW. New targets needing reduced laser energy with only a small decrease in robustness have then been designed for this purpose. Working specifically on the coupling efficiency parameter, i.e. the ratio of the energy absorbed by the capsule to the laser energy, has led to the design of a rugby-shaped cocktail hohlraum. 1D and 2D robustness evaluations of these different targets shed light on critical points for ignition, that can be traded off by tightening some specifications or by preliminary experimental and numerical tuning experiments.

  11. Progress on LMJ targets for ignition

    International Nuclear Information System (INIS)

    Cherfils-Clerouin, C; Boniface, C; Bonnefille, M; Dattolo, E; Galmiche, D; Gauthier, P; Giorla, J; Laffite, S; Liberatore, S; Loiseau, P; Malinie, G; Masse, L; Masson-Laborde, P E; Monteil, M C; Poggi, F; Seytor, P; Wagon, F; Willien, J L

    2009-01-01

    Targets designed to produce ignition on the Laser Megajoule (LMJ) are being simulated in order to set specifications for target fabrication. The LMJ experimental plans include the attempt of ignition and burn of an ICF capsule with 160 laser beams, delivering up to 1.4 MJ and 380 TW. New targets needing reduced laser energy with only a small decrease in robustness have then been designed for this purpose. Working specifically on the coupling efficiency parameter, i.e. the ratio of the energy absorbed by the capsule to the laser energy, has led to the design of a rugby-ball shaped cocktail hohlraum; with these improvements, a target based on the 240-beam A1040 capsule can be included in the 160-beam laser energy-power space. Robustness evaluations of these different targets shed light on critical points for ignition, which can trade off by tightening some specifications or by preliminary experimental and numerical tuning experiments.

  12. The National Ignition Facility and Industry

    Science.gov (United States)

    Harri, J. G.; Paisner, J. A.; Lowdermilk, W. H.; Boyes, J. D.; Kumpan, S. A.; Sorem, M. S.

    1994-09-01

    The mission of the National Ignition Facility is to achieve ignition and gain in inertial confinement fusion targets in the laboratory. The facility will be used for defense applications such as weapons physics and weapons effects testing, and for civilian applications such as fusion energy development and fundamental studies of matter at high temperatures and densities. The National Ignition Facility construction project will require the best of our construction industries and its success will depend on the best products offered by hundreds of the nation's high technology companies. Three-fourths of the construction costs will be invested in industry. This article reviews the design, cost and schedule, and required industrial involvement associated with the construction project.

  13. The National Ignition Facility and industry

    International Nuclear Information System (INIS)

    Harri, J.G.; Lowdermilk, W.H.; Paisner, J.A.; Boyes, J.D.; Kumpan, S.A.; Sorem, M.S.

    1994-01-01

    The mission of the National Ignition Facility is to achieve ignition and gain in inertial confinement fusion targets in the laboratory. The facility will be used for defense applications such as weapons physics and weapons effects testing, and for civilian applications such as fusion energy development and fundamental studies of matter at high temperatures and densities. The National Ignition Facility construction project will require the best of national construction industries and its success will depend on the best products offered by hundreds of the nation's high technology companies. Three-fourths of the construction costs will be invested in industry. This article reviews the design, cost and schedule, and required industrial involvement associated with the construction project

  14. Target Visualization at the National Ignition Facility

    Energy Technology Data Exchange (ETDEWEB)

    Potter, Daniel Abraham [Univ. of California, Davis, CA (United States)

    2011-01-01

    As the National Ignition Facility continues its campaign to achieve ignition, new methods and tools will be required to measure the quality of the targets used to achieve this goal. Techniques have been developed to measure target surface features using a phase-shifting diffraction interferometer and Leica Microsystems confocal microscope. Using these techniques we are able to produce a detailed view of the shell surface, which in turn allows us to refine target manufacturing and cleaning processes. However, the volume of data produced limits the methods by which this data can be effectively viewed by a user. This paper introduces an image-based visualization system for data exploration of target shells at the National Ignition Facility (NIF) at Lawrence Livermore National Laboratory. It aims to combine multiple image sets into a single visualization to provide a method of navigating the data in ways that are not possible with existing tools.

  15. Ignition in the next step tokamak

    International Nuclear Information System (INIS)

    Johner, J.

    1990-07-01

    A 1/2-D model for thermal equilibrium of a thermonuclear plasma with transport described by an empirical global energy confinement time is described. Ignition in NET and ITER is studied for a number of energy confinement time scaling expressions. Ignited operation of these machines at the design value of the neutron wall load is shown to satisfy both beta and density constraints. The value of the confinement time enhancement factor required for such operation is found to be lower for the more recently proposed scaling expressions than it is for the oldest ones. With such new scalings, ignition could be obtained in H-mode in NET and ITER even with relatively flat density profiles

  16. Laser ignited engines: progress, challenges and prospects.

    Science.gov (United States)

    Dearden, Geoff; Shenton, Tom

    2013-11-04

    Laser ignition (LI) has been shown to offer many potential benefits compared to spark ignition (SI) for improving the performance of internal combustion (IC) engines. This paper outlines progress made in recent research on laser ignited IC engines, discusses the potential advantages and control opportunities and considers the challenges faced and prospects for its future implementation. An experimental research effort has been underway at the University of Liverpool (UoL) to extend the stratified speed/load operating region of the gasoline direct injection (GDI) engine through LI research, for which an overview of some of the approaches, testing and results to date are presented. These indicate how LI can be used to improve control of the engine for: leaner operation, reductions in emissions, lower idle speed and improved combustion stability.

  17. Improving the ignition quality of fuels

    KAUST Repository

    Sarathy, Mani; Wang, Zhandong; Shankar, Vijai Shankar Bhavani

    2017-01-01

    Provided herein are compounds and methods of producing compounds for improving ignition quality and combustion efficiency of fuels, for example fossil fuels. In various aspects we generate highly oxygenated compounds from hydrocarbon feedstocks. The feedstock can be a branched alkane or n-alkane having a chain length greater than or equal to 6, a cycloalkane with a 5 or 6 membered ring structure, or a alkylated cycloalkane with 5 or more carbon atoms. The reactant can be fed in the gas- phase to a partial oxidation reactor (with or without a catalyst), and at a fixed temperature, mixture composition, and residence time. The reactant can be converted to a mixture of products including keto hydroperoxides, diketo hydroperoxides, keto dihydroperoxides, hydroperoxyl cyclic ethers, and alkenyl hydroperoxides. The compounds are inherently unstable and can quickly decompose to highly reactive radical species that can be used to improve the ignition quality of a fuel and advance ignition in an engine.

  18. National Ignition Facility Target Chamber

    International Nuclear Information System (INIS)

    Wavrik, R W; Cox, J R; Fleming, P J

    2000-01-01

    On June 11, 1999 the Department of Energy dedicated the single largest piece of the National Ignition Facility (NIF) at Lawrence Livermore National Laboratory (LLNL) in Livermore, California. The ten (10) meter diameter aluminum target high vacuum chamber will serve as the working end of the largest laser in the world. The output of 192 laser beams will converge at the precise center of the chamber. The laser beams will enter the chamber in two by two arrays to illuminate 10 millimeter long gold cylinders called hohlraums enclosing 2 millimeter capsule containing deuterium, tritium and isotopes of hydrogen. The two isotopes will fuse, thereby creating temperatures and pressures resembling those found only inside stars and in detonated nuclear weapons, but on a minute scale. The NIF Project will serve as an essential facility to insure safety and reliability of our nation's nuclear arsenal as well as demonstrating inertial fusion's contribution to creating electrical power. The paper will discuss the requirements that had to be addressed during the design, fabrication and testing of the target chamber. A team from Sandia National Laboratories (SNL) and LLNL with input from industry performed the configuration and basic design of the target chamber. The method of fabrication and construction of the aluminum target chamber was devised by Pitt-Des Moines, Inc. (PDM). PDM also participated in the design of the chamber in areas such as the Target Chamber Realignment and Adjustment System, which would allow realignment of the sphere laser beams in the event of earth settlement or movement from a seismic event. During the fabrication of the target chamber the sphericity tolerances had to be addressed for the individual plates. Procedures were developed for forming, edge preparation and welding of individual plates. Construction plans were developed to allow the field construction of the target chamber to occur parallel to other NIF construction activities. This was

  19. Transport simulations of ohmic ignition experiment: IGNITEX

    International Nuclear Information System (INIS)

    Uckan, N.A.; Howe, H.C.

    1987-01-01

    The IGNITEX device, proposed by Rosenbluth et al., is a compact, super-high-field, high-current, copper-coil tokamak envisioned to reach ignition with ohmic (OH) heating alone. Several simulations of IGNITEX were made with a 0-D global model and with the 1-D PROCTR transport code. It is shown that OH ignition is a sensitive function of the assumptions about density profile, wall reflectivity of synchrotron radiation, impurity radiation, plasma edge conditions, and additional anomalous losses. In IGNITEX, OH ignition is accessible with nearly all scalings based on favorable OH confinement (such as neo-Alcator). Also, OH ignition appears to be accessible for most (not all) L-mode scalings (such as Kaye-Goldston), provided that the density profile is not too broad (parabolic or more peaked profiles are needed), Z/sub eff/ is not too large (≤2), and anomalous radiation and alpha losses and/or other enhanced transport losses (/eta//sub i/ modes, edge convective energy losses, etc.) are not present. In IGNITEX, because the figure-of-merit parameters (aB 0 2 /q* /approximately/ IB 0 , etc.) are large, ignition can be accessed (either with OH heating alone or with the aid of a small amount of auxiliary power) at relatively low beta, far from stability limits. Once the plasma is ignited, thermal runaway is prevented naturally by a combination of increased synchrotron radiation, burnout of the fuel in the plasma core and replacement by thermal alphas, and the reduction in the thermal plasma confinement assumed in L-mode-like scalings. 12 refs., 5 figs., 1 tab

  20. Transport simulations of ohmic ignition experiment: IGNITEX

    International Nuclear Information System (INIS)

    Uckan, N.A.; Howe, H.C.

    1987-12-01

    The IGNITEX device, proposed by Rosenbluth et al., is a compact, super-high-field, high-current, copper-coil tokamak envisioned to reach ignition with ohmic (OH) heating alone. Several simulations of IGNITEX were made with a 0-D global model and with the 1-D PROCTR transport code. It is shown that OH ignition is a sensitive function of the assumptions about density profile, wall reflectivity of synchrotron radiation, impurity radiation, plasma edge conditions, and additional anomalous losses. In IGNITEX, OH ignition is accessible with nearly all scalings based on favorable OH confinement (such as neo-Alcator). Also, OH ignition appears to be accessible for most (not all) L-mode scalings (such as Kaye-Goldston), provided that the density profile is not too broad (parabolic or more peaked profiles are needed), Z/sub eff/ is not too large, and anomalous radiation and alpha losses and/or other enhanced transport losses (eta/sub i/ modes, edge convective energy losses, etc.) are not present. In IGNITEX, because the figure-of-merit parameters are large, ignition can be accessed (either with OH heating alone or with the aid of a small amount of auxiliary power) at relatively low beta, far from stability limits. Once the plasma is ignited, thermal runaway is prevented naturally by a combination of increased synchrotron radiation, burnout of the fuel in the plasma core and replacement by thermal alphas, and the reduction in the thermal plasma confinement assumed in L-mode-like scalings. 12 refs., 5 figs., 1 tab

  1. Robustness studies of ignition targets for the National Ignition Facility in two dimensions

    International Nuclear Information System (INIS)

    Clark, Daniel S.; Haan, Steven W.; Salmonson, Jay D.

    2008-01-01

    Inertial confinement fusion capsules are critically dependent on the integrity of their hot spots to ignite. At the time of ignition, only a certain fractional perturbation of the nominally spherical hot spot boundary can be tolerated and the capsule still achieve ignition. The degree to which the expected hot spot perturbation in any given capsule design is less than this maximum tolerable perturbation is a measure of the ignition margin or robustness of that design. Moreover, since there will inevitably be uncertainties in the initial character and implosion dynamics of any given capsule, all of which can contribute to the eventual hot spot perturbation, quantifying the robustness of that capsule against a range of parameter variations is an important consideration in the capsule design. Here, the robustness of the 300 eV indirect drive target design for the National Ignition Facility [Lindl et al., Phys. Plasmas 11, 339 (2004)] is studied in the parameter space of inner ice roughness, implosion velocity, and capsule scale. A suite of 2000 two-dimensional simulations, run with the radiation hydrodynamics code LASNEX, is used as the data base for the study. For each scale, an ignition region in the two remaining variables is identified and the ignition cliff is mapped. In accordance with the theoretical arguments of Levedahl and Lindl [Nucl. Fusion 37, 165 (1997)] and Kishony and Shvarts [Phys. Plasmas 8, 4925 (2001)], the location of this cliff is fitted to a power law of the capsule implosion velocity and scale. It is found that the cliff can be quite well represented in this power law form, and, using this scaling law, an assessment of the overall (one- and two-dimensional) ignition margin of the design can be made. The effect on the ignition margin of an increase or decrease in the density of the target fill gas is also assessed

  2. An Additively Manufactured Torch Igniter for Liquid Propellants

    Data.gov (United States)

    National Aeronautics and Space Administration — Consistent and reliable rocket engine ignition has yet to be proven through an additively manufactured torch igniter for liquid propellants. The coupling of additive...

  3. National Ignition Facility project acquisition plan revision 1

    International Nuclear Information System (INIS)

    Clobes, A.R.

    1996-01-01

    The purpose of this National Ignition Facility Acquisition Plan is to describe the overall procurement strategy planned for the National Ignition Facility M Project. It was prepared for the NIP Prood Office by the NIF Procurement Manager

  4. Impact of fuel molecular structure on auto-ignition behavior – Design rules for future high performance gasolines

    KAUST Repository

    Boot, Michael D.

    2016-12-29

    At a first glance, ethanol, toluene and methyl tert-butyl ether look nothing alike with respect to their molecular structures. Nevertheless, all share a similarly high octane number. A comprehensive review of the inner workings of such octane boosters has been long overdue, particularly at a time when feedstocks for transport fuels other than crude oil, such as natural gas and biomass, are enjoying a rapidly growing market share. As high octane fuels sell at a considerable premium over gasoline, diesel and jet fuel, new entrants into the refining business should take note and gear their processes towards knock resistant compounds if they are to maximize their respective bottom lines. Starting from crude oil, the route towards this goal is well established. Starting from biomass or natural gas, however, it is less clear what dots on the horizon to aim for. The goal of this paper is to offer insight into the chemistry behind octane boosters and to subsequently distill from this knowledge, taking into account recent advances in engine technology, multiple generic design rules that guarantee good anti-knock performance. Careful analysis of the literature suggests that highly unsaturated (cyclic) compounds are the preferred octane boosters for modern spark-ignition engines. Additional side chains of any variety will dilute this strong performance. Multi-branched paraffins come in distant second place, owing to their negligible sensitivity. Depending on the type and location of functional oxygen groups, oxygenates can have a beneficial, neutral or detrimental impact on anti-knock quality.

  5. Thermonuclear ignition in the next generation tokamaks

    International Nuclear Information System (INIS)

    Johner, J.

    1989-04-01

    The extrapolation of experimental rules describing energy confinement and magnetohydrodynamic - stability limits, in known tokamaks, allow to show that stable thermonuclear ignition equilibria should exist in this configuration, if the product aB t x of the dimensions by a magnetic-field power is large enough. Quantitative application of this result to several next-generation tokamak projects show that those kinds of equilibria could exist in such devices, which would also have enough additional heating power to promote an effective accessible ignition

  6. Nova Upgrade program: ignition and beyond

    International Nuclear Information System (INIS)

    Storm, E.; Campbell, E.M.; Hogan, W.J.; Lindl, J.D.

    1993-01-01

    The Lawrence Livermore National Laboratory (LLNL) Inertial Confinement Fusion (ICF) Program is addressing the critical physics and technology issues directed toward demonstrating and exploiting ignition and propagating burn to high gain with ICF targets for both defense and civilian applications. Nova is the primary U.S. facility employed in the study of the X-ray-driven (indirect drive) approach to ICF. Nova's principal objective is to demonstrate that laser-driven hohlraums can achieve the conditions of driver-target coupling efficiency, driver irradiation symmetry, driver pulseshaping, target preheat, and hydrodynamic stability required by hot-spot ignition and fuel compression to realize a fusion gain. (author)

  7. Structural features of the Compact Ignition Tokamak

    International Nuclear Information System (INIS)

    Citrolo, J.; Brown, G.; Rogoff, P.

    1987-01-01

    The Compact Ignition Tokamak (CIT) is undergoing preliminary structural design and definitions. It will be relatively inexpensive with ignition capabilities. During the definition phase it was concluded that the TF coil should be assembled from the laminate copper-Inconel plates since copper alone cannot sustain the expected magnetic and thermal loads. An extensive test program is being initiated to investigate the various materials, and their elastic and inelastic response and to develop the constitutive equations required for the selection of design criteria and for the stress analysis of this device. Finite element analysis nonlinear material capabilities are being used to study, predict and correlate the machine behavior

  8. Plasma igniter for internal combustion engine

    Science.gov (United States)

    Fitzgerald, D. J.; Breshears, R. R. (Inventor)

    1978-01-01

    An igniter for the air/fuel mixture used in the cylinders of an internal combustion engine is described. A conventional spark is used to initiate the discharge of a large amount of energy stored in a capacitor. A high current discharge of the energy in the capacitor switched on by a spark discharge produces a plasma and a magnetic field. The resultant combined electromagnetic current and magnetic field force accelerates the plasma deep into the combustion chamber thereby providing an improved ignition of the air/fuel mixture in the chamber.

  9. Chaotic combustion in spark ignition engines

    International Nuclear Information System (INIS)

    Wendeker, Miroslaw; Czarnigowski, Jacek; Litak, Grzegorz; Szabelski, Kazimierz

    2003-01-01

    We analyse the combustion process in a spark ignition engine using the experimental data of an internal pressure during the combustion process and show that the system can be driven to chaotic behaviour. Our conclusion is based on the observation of unperiodicity in the time series, suitable stroboscopic maps and a complex structure of a reconstructed strange attractor. This analysis can explain that in some circumstances the level of noise in spark ignition engines increases considerably due to nonlinear dynamics of a combustion process

  10. Place Branding in Systems of Place

    DEFF Research Database (Denmark)

    Zenker, Sebastian; Andéhn, Mikael

    2015-01-01

    , this presents a challenge, since the role of a place in this system of geographical abstractions constitutes a piece of information more vital than any other in defining the place. Our understanding of places cannot be separated from their scale, and any effort at managing the reputation and meaning.......g. the European Union or Africa). Using the example of nation branding for Sudan and Slovenia, one can identify supranational places such as “sub-Saharan Africa” or “Eastern Europe”, carrying their own highly salient and often negative meaning in much of the Western world. We explore how association to a system...

  11. Performance metrics for Inertial Confinement Fusion implosions: aspects of the technical framework for measuring progress in the National Ignition Campaign

    International Nuclear Information System (INIS)

    Spears, B.K.; Glenzer, S.; Edwards, M.J.; Brandon, S.; Clark, D.; Town, R.; Cerjan, C.; Dylla-Spears, R.; Mapoles, E.; Munro, D.; Salmonson, J.; Sepke, S.; Weber, S.; Hatchett, S.; Haan, S.; Springer, P.; Moses, E.; Mapoles, E.; Munro, D.; Salmonson, J.; Sepke, S.

    2011-01-01

    The National Ignition Campaign (NIC) uses non-igniting 'THD' capsules to study and optimize the hydrodynamic assembly of the fuel without burn. These capsules are designed to simultaneously reduce DT neutron yield and to maintain hydrodynamic similarity with the DT ignition capsule. We will discuss nominal THD performance and the associated experimental observables. We will show the results of large ensembles of numerical simulations of THD and DT implosions and their simulated diagnostic outputs. These simulations cover a broad range of both nominal and off nominal implosions. We will focus on the development of an experimental implosion performance metric called the experimental ignition threshold factor (ITFX). We will discuss the relationship between ITFX and other integrated performance metrics, including the ignition threshold factor (ITF), the generalized Lawson criterion (GLC), and the hot spot pressure (HSP). We will then consider the experimental results of the recent NIC THD campaign. We will show that we can observe the key quantities for producing a measured ITFX and for inferring the other performance metrics. We will discuss trends in the experimental data, improvement in ITFX, and briefly the upcoming tuning campaign aimed at taking the next steps in performance improvement on the path to ignition on NIF.

  12. Performance metrics for Inertial Confinement Fusion implosions: aspects of the technical framework for measuring progress in the National Ignition Campaign

    Energy Technology Data Exchange (ETDEWEB)

    Spears, B K; Glenzer, S; Edwards, M J; Brandon, S; Clark, D; Town, R; Cerjan, C; Dylla-Spears, R; Mapoles, E; Munro, D; Salmonson, J; Sepke, S; Weber, S; Hatchett, S; Haan, S; Springer, P; Moses, E; Mapoles, E; Munro, D; Salmonson, J; Sepke, S

    2011-12-16

    The National Ignition Campaign (NIC) uses non-igniting 'THD' capsules to study and optimize the hydrodynamic assembly of the fuel without burn. These capsules are designed to simultaneously reduce DT neutron yield and to maintain hydrodynamic similarity with the DT ignition capsule. We will discuss nominal THD performance and the associated experimental observables. We will show the results of large ensembles of numerical simulations of THD and DT implosions and their simulated diagnostic outputs. These simulations cover a broad range of both nominal and off nominal implosions. We will focus on the development of an experimental implosion performance metric called the experimental ignition threshold factor (ITFX). We will discuss the relationship between ITFX and other integrated performance metrics, including the ignition threshold factor (ITF), the generalized Lawson criterion (GLC), and the hot spot pressure (HSP). We will then consider the experimental results of the recent NIC THD campaign. We will show that we can observe the key quantities for producing a measured ITFX and for inferring the other performance metrics. We will discuss trends in the experimental data, improvement in ITFX, and briefly the upcoming tuning campaign aimed at taking the next steps in performance improvement on the path to ignition on NIF.

  13. Ignition experiment in a single-turn-coil tokamak

    International Nuclear Information System (INIS)

    Carrera, R.; Driga, M.; Gully, J.H.

    1989-01-01

    A novel concept for a fusion ignition experiment, IGNITEX proposed along the lines of previous ideas for a compact thermonuclear device is analyzed. A single-turn-coil tokamak is analyzed. A single-turn-coil tokamak supplied by homopolar generators can ohmically heat a DT plasma to ignition conditions and maintain a thermally stable ignited phase for about ten energy confinement times. The IGNITEX experiment can provide a simple and relatively inexpensive way to produce and control ignited plasmas for scientific study

  14. Maintenance features of the Compact Ignition Tokamak fusion reactor

    International Nuclear Information System (INIS)

    Spampinato, P.T.; Hager, E.R.

    1987-01-01

    The Compact Ignition Tokamak (CIT) is envisaged to be the next experimental machine in the US Fusion Program. Its use of deuterium/tritium fuel requires the implementation of remote handling technology for maintenance and disassembly operations. The reactor is surrounded by a close-proximity nuclear shield which is designed to permit personnel access within the test cell, one day after shutdown. With the shield in place, certain maintenance activities in the cell may be done hands-on. Maintenance on the reactor is accomplished remotely using a boom-mounted manipulator after disassembling the shield. Maintenance within the plasma chamber is accomplished with two articulated boom manipulators that are capable of operating in a vacuum environment. They are stored in a vacuum enclosure behind movable shield plugs

  15. Analysis of cyclic variations during mode switching between spark ignition and controlled auto-ignition combustion operations

    OpenAIRE

    Chen, T; Zhao, H; Xie, H; He, B

    2014-01-01

    © IMechE 2014. Controlled auto-ignition, also known as homogeneous charge compression ignition, has been the subject of extensive research because of their ability to provide simultaneous reductions in fuel consumption and NOx emissions from a gasoline engine. However, due to its limited operation range, switching between controlled auto-ignition and spark ignition combustion is needed to cover the complete operating range of a gasoline engine for passenger car applications. Previous research...

  16. Design of a deuterium and tritium-ablator shock ignition target for the National Ignition Facility

    International Nuclear Information System (INIS)

    Terry, Matthew R.; Perkins, L. John; Sepke, Scott M.

    2012-01-01

    Shock ignition presents a viable path to ignition and high gain on the National Ignition Facility (NIF). In this paper, we describe the development of the 1D design of 0.5 MJ class, all-deuterium and tritium (fuel and ablator) shock ignition target that should be reasonably robust to Rayleigh-Taylor fluid instabilities, mistiming, and hot electron preheat. The target assumes “day one” NIF hardware and produces a yield of 31 MJ with reasonable allowances for laser backscatter, absorption efficiency, and polar drive power variation. The energetics of polar drive laser absorption require a beam configuration with half of the NIF quads dedicated to launching the ignitor shock, while the remaining quads drive the target compression. Hydrodynamic scaling of the target suggests that gains of 75 and yields 70 MJ may be possible.

  17. Ignition delay times of Gasoline Distillation Cuts measured with Ignition Quality Tester

    KAUST Repository

    Naser, Nimal; Singh, Eshan; Ahmed, Ahfaz; Sarathy, Mani

    2017-01-01

    Tailoring fuel properties to maximize the efficiency of internal combustion engines is a way towards achieving cleaner combustion systems. In this work, the ignition properties of various gasoline fuel distillation cuts are analyzed to better

  18. Modelling auto ignition of hydrogen in a jet ignition pre-chamber

    Energy Technology Data Exchange (ETDEWEB)

    Boretti, Alberto A. [School of Science and Engineering, University of Ballarat, PO Box 663, Ballarat, Victoria 3353 (Australia)

    2010-04-15

    Spark-less jet ignition pre-chambers are enablers of high efficiencies and load control by quantity of fuel injected when coupled with direct injection of main chamber fuel, thus permitting always lean burn bulk stratified combustion. Towards the end of the compression stroke, a small quantity of hydrogen is injected within the pre-chamber, where it mixes with the air entering from the main chamber. Combustion of the air and fuel mixture then starts within the pre-chamber because of the high temperature of the hot glow plug, and then jets of partially combusted hot gases enter the main chamber igniting there in the bulk, over multiple ignition points, lean stratified mixtures of air and fuel. The paper describes the operation of the spark-less jet ignition pre-chamber coupling CFD and CAE engine simulations to allow component selection and engine performance evaluation. (author)

  19. National Ignition Facility Title II Design Plan

    International Nuclear Information System (INIS)

    Kumpan, S

    1997-01-01

    This National Ignition Facility (NIF) Title II Design Plan defines the work to be performed by the NIF Project Team between November 1996, when the U.S. Department of Energy (DOE) reviewed Title I design and authorized the initiation of Title H design and specific long-lead procurements, and September 1998, when Title 11 design will be completed

  20. Physics of ignition for ICF capsules

    International Nuclear Information System (INIS)

    Lindl, J.D.

    1989-01-01

    The implosion of an ICF capsule must accomplish both compression of the main fuel to several hundred grams per cubic centimeter and heating and compression of the central region of the fuel to ignition. This report discusses the physics of these conditions

  1. Tests of an experimental slash ignition unit

    Science.gov (United States)

    James L. Murphy; Harry E. Schimke

    1965-01-01

    A prototype ignition package containing an incendiary powder and designed for slash and brush burning jobs showed some promise, but the unit tested was not superior to such conventional devices as fusees, diesel backpack type flamethrowers, Very pistols, and drip torches.

  2. Impacts assessment for the National Ignition Facility

    Energy Technology Data Exchange (ETDEWEB)

    Bay Area Economics

    1996-12-01

    This report documents the economic and other impacts that will be created by the National Ignition Facility (NIF) construction and ongoing operation, as well as the impacts that may be created by new technologies that may be developed as a result of NIF development and operation.

  3. Piloted ignition of live forest fuels

    Science.gov (United States)

    S. McAllister; I. Grenfell; A. Hadlow; W. M. Jolly; M. Finney; J. Cohen

    2012-01-01

    The most unpredictable and uncontrollable wildfires are those that burn in the crowns of live vegetation. The fuels that feed these crown fires are mostly live, green foliage. Unfortunately, little is known about how live fuels combust. To understand how live fuels burn, piloted ignition experiments were performed with lodgepole pine and Douglas-fir. The thermal...

  4. Plasma ignition for medium calibre ammunition

    NARCIS (Netherlands)

    Driel, C.A. van; Schilt, A.; Simor, M.; Schaffers, P.; Weise, T.

    2012-01-01

    Gun performance is usually affected by the operating temperature of the ammunition or weapon. This is caused by several factors, amongst which the temperature dependency of the propellant ignition and combustion processes. Compensation of temperature effects on weapon or ammunition performance is

  5. National Ignition Facility design focuses on optics

    International Nuclear Information System (INIS)

    Hogan, W.J.; Atherton, L.J.; Paisner, J.A.

    1996-01-01

    Sometime in the year 2002, scientists at the National Ignition Facility (NIF) will focus 192 separate high-power ultraviolet laser beams onto a tiny capsule of deuterium and tritium, heating and compressing the material until it ignites and burns with a burst of fusion energy. The mission of NIF, which will contain the largest laser in the world, is to obtain fusion ignition and gain and to use inertial confinement fusion capabilities in nuclear weapons science experiments. The physics data provided by NIF experiments will help scientists ensure nuclear weapons reliability without the need for actual weapons tests; basic sciences such as astrophysics will also benefit. The facility faces stringent weapons-physics user requirements demanding peak pulse powers greater than 750 TW at 0.35 microm (only 500 TW is required for target ignition), pulse durations of 0.1 to 20 ns, beam steering on the order of several degrees, and target isolation from residual 1- and 0.5-microm radiation. Additional requirements include 50% fractional encircled beam energy in a 100-microm-diameter spot, with 95% encircled in a 200-microm spot. The weapons-effects community requires 1- and 0.5-microm light on target, beam steering to widely spaced targets, a target chamber accommodating oversized objects, well-shielded diagnostic areas, and elimination of stray light in the target chamber. The beamline design, amplifier configuration and requirements for optics are discussed here

  6. Diagnosing ignition with DT reaction history

    International Nuclear Information System (INIS)

    Wilson, D. C.; Bradley, P. A.; Herrmann, H. W.; Cerjan, C. J.; Salmonson, J. D.; Spears, B. K.; Hatchet, S. P. II; Glebov, V. Yu.

    2008-01-01

    A full range DT reaction history of an ignition capsule, from 10 9 to 10 20 neutrons/ns, offers the opportunity to diagnose fuel conditions hundreds of picoseconds before and during burn. The burn history begins with a sharp rise when the first shock reaches the center of the capsule. The level of this jump reflects the combined shock strength and the adiabat of DT fuel. Changes to the four laser pulses driving the capsule implosion which are large enough to degrade the yield make measurable changes to the reaction history. Low mode asymmetries grow during convergence but change the reaction history during the final ∼100 ps. High mode asymmetry or turbulence mixing affects only the reaction history within ∼50 ps of peak burn rate. A capsule with a tritium fuel layer containing a small amount of deuterium (∼1%) creates a reaction history similar to the ignition capsule, but without the final ignition burn. A combination of gas Cerenkov detectors and the neutron temporal diagnostic could be capable of diagnosing the full history of ignition and tritium rich capsules.

  7. Physics evaluation of compact tokamak ignition experiments

    International Nuclear Information System (INIS)

    Uckan, N.A.; Houlberg, W.A.; Sheffield, J.

    1985-01-01

    At present, several approaches for compact, high-field tokamak ignition experiments are being considered. A comprehensive method for analyzing the potential physics operating regimes and plasma performance characteristics of such ignition experiments with O-D (analytic) and 1-1/2-D (WHIST) transport models is presented. The results from both calculations are in agreement and show that there are regimes in parameter space in which a class of small (R/sub o/ approx. 1-2 m), high-field (B/sub o/ approx. 8-13 T) tokamaks with aB/sub o/ 2 /q/sub */ approx. 25 +- 5 and kappa = b/a approx. 1.6-2.0 appears ignitable for a reasonable range of transport assumptions. Considering both the density and beta limits, an evaluation of the performance is presented for various forms of chi/sub e/ and chi/sub i/, including degradation at high power and sawtooth activity. The prospects of ohmic ignition are also examined. 16 refs., 13 figs

  8. Power conditioning for the National Ignition Facility

    International Nuclear Information System (INIS)

    Larson, D.W.; Anderson, R.; Boyes, J.

    1994-01-01

    A cost-effective, 320-MJ power-conditioning system has been completed for the proposed National Ignition Facility (NIF). The design features include metallized dielectric capacitors, a simple topology, and large (1.6-MJ) module size. Experimental results address the technical risks associated with the design

  9. Understanding Biomass Ignition in Power Plant Mills

    DEFF Research Database (Denmark)

    Schwarzer, Lars; Jensen, Peter Arendt; Glarborg, Peter

    2017-01-01

    Converting existing coal fired power plants to biomass is a readily implemented strategy to increase the share of renewable energy. However, changing from one fuel to another is not straightforward: Experience shows that wood pellets ignite more readily than coal in power plant mills or storages...

  10. Ignition of Propellants Through Nanostructured Materials

    Science.gov (United States)

    2016-03-31

    aluminum nano-particles and solid oxidizers such as ammonium perchlorate on the photo-ignition characteristics. We found that by mixing carbon...sensitive microphone (Piezotronic Inc. model S05692) for detection of any photo-acoustic signal, and an XYZ traversing stage with a filter wheel for

  11. National Ignition Facility frequency converter development

    International Nuclear Information System (INIS)

    Barker, C.E.; Auerbach, J.M.; Adams, C.H.

    1996-01-01

    A preliminary error budget for the third harmonic converter for the National Ignition Facility (NIF) laser driver has been developed using a root-sum-square-accumulation of error sources. Such a budget sets an upper bound on the allowable magnitude of the various effects that reduce conversion efficiency. Development efforts on crystal mounting technology and crystal quality studies are discussed

  12. Lubricant induced pre-ignition in an optical spark-ignition engine

    OpenAIRE

    Dingle, Simon Frederick

    2014-01-01

    This thesis was submitted for the award of Doctor of Philosophy and was awarded by Brunel University London This work focuses on the introduction of lubricant into the combustion chamber and the effect that this has on pre-ignition. Apparently for the first time, the work presented provides detailed full-bore optical data for lubricant induced pre-ignition and improves understanding of the super-knock phenomena that affects modern downsized gasoline engines. A new single-cylinder optical r...

  13. New designs of LMJ targets for early ignition experiments

    International Nuclear Information System (INIS)

    Clerouin, C; Bonnefille, M; Dattolo, E; Fremerye, P; Galmiche, D; Gauthier, P; Giorla, J; Laffite, S; Liberatore, S; Loiseau, P; Malinie, G; Masse, L; Poggi, F; Seytor, P

    2008-01-01

    The LMJ experimental plans include the attempt of ignition and burn of an ICF capsule with 40 laser quads, delivering up to 1.4MJ and 380TW. New targets needing reduced laser energy with only a small decrease in robustness are then designed for this purpose. A first strategy is to use scaled-down cylindrical hohlraums and capsules, taking advantage of our better understanding of the problem, set on theoretical modelling, simulations and experiments. Another strategy is to work specifically on the coupling efficiency parameter, i.e. the ratio of the energy absorbed by the capsule to the laser energy, which is with parametric instabilities a crucial drawback of indirect drive. An alternative design is proposed, made up of the nominal 60 quads capsule, named A1040, in a rugby-shaped hohlraum. Robustness evaluations of these different targets are in progress

  14. New designs of LMJ targets for early ignition experiments

    Energy Technology Data Exchange (ETDEWEB)

    Clerouin, C; Bonnefille, M; Dattolo, E; Fremerye, P; Galmiche, D; Gauthier, P; Giorla, J; Laffite, S; Liberatore, S; Loiseau, P; Malinie, G; Masse, L; Poggi, F; Seytor, P [Commissariat a l' Energie Atomique, DAM-Ile de France, BP 12 91680 Bruyeres-le-Chatel (France)], E-mail: catherine.cherfils@cea.fr

    2008-05-15

    The LMJ experimental plans include the attempt of ignition and burn of an ICF capsule with 40 laser quads, delivering up to 1.4MJ and 380TW. New targets needing reduced laser energy with only a small decrease in robustness are then designed for this purpose. A first strategy is to use scaled-down cylindrical hohlraums and capsules, taking advantage of our better understanding of the problem, set on theoretical modelling, simulations and experiments. Another strategy is to work specifically on the coupling efficiency parameter, i.e. the ratio of the energy absorbed by the capsule to the laser energy, which is with parametric instabilities a crucial drawback of indirect drive. An alternative design is proposed, made up of the nominal 60 quads capsule, named A1040, in a rugby-shaped hohlraum. Robustness evaluations of these different targets are in progress.

  15. Relating the octane numbers of fuels to ignition delay times measured in an ignition quality tester (IQT)

    KAUST Repository

    Naser, Nimal; Yang, Seung Yeon; Kalghatgi, Gautam; Chung, Suk-Ho

    2016-01-01

    an ignition quality tester. A baseline data of ignition delay times were determined using an ignition quality tester at a charge pressure of 21.3 bar between 770 and 850 K and an equivalence ratio of 0.7 for various primary reference fuels (PRFs, mixtures

  16. Improvements to the Composition of Fusel Oil and Analysis of the Effects of Fusel Oil–Gasoline Blends on a Spark-Ignited (SI Engine’s Performance and Emissions

    Directory of Open Access Journals (Sweden)

    Suleyman Simsek

    2018-03-01

    Full Text Available With the increase of energy needs and environmental pollution, alcohol-based alternative fuels are used in spark-ignited (SI engines. Fusel oil, which is a by-product obtained through distillation of ethanol, contains some valuable alcohols. As alcohols are high-octane, they have an important place among the alternative fuels. Fusel also takes its place among those alternatives as it is high-octane and low on exhaust emissions. In this research, the effects of using blends of unleaded gasoline and improved fusel oil on engine performance and exhaust emissions were analyzed experimentally. A four-stroke, single-cylinder, spark-ignited engine was used in the experiments. The tests were conducted at a fixed speed and under different loads. The test fuels were blended supplying with fusel oil at rates incremented by 10%, up to 50%. Under each load, the engine’s performance and emissions were measured. Throughout the experiments, it has been observed that engine torque and specific fuel consumption increases as the amount of fusel oil in the blend is increased. Nitrogen oxide (NOx, carbon monoxide (CO, and hydrocarbon (HC emissions are reduced as the amount of fusel oil in the blends is increased.

  17. Fundamental Studies of Ignition Process in Large Natural Gas Engines Using Laser Spark Ignition

    Energy Technology Data Exchange (ETDEWEB)

    Azer Yalin; Bryan Willson

    2008-06-30

    Past research has shown that laser ignition provides a potential means to reduce emissions and improve engine efficiency of gas-fired engines to meet longer-term DOE ARES (Advanced Reciprocating Engine Systems) targets. Despite the potential advantages of laser ignition, the technology is not seeing practical or commercial use. A major impediment in this regard has been the 'open-path' beam delivery used in much of the past research. This mode of delivery is not considered industrially practical owing to safety factors, as well as susceptibility to vibrations, thermal effects etc. The overall goal of our project has been to develop technologies and approaches for practical laser ignition systems. To this end, we are pursuing fiber optically coupled laser ignition system and multiplexing methods for multiple cylinder engine operation. This report summarizes our progress in this regard. A partial summary of our progress includes: development of a figure of merit to guide fiber selection, identification of hollow-core fibers as a potential means of fiber delivery, demonstration of bench-top sparking through hollow-core fibers, single-cylinder engine operation with fiber delivered laser ignition, demonstration of bench-top multiplexing, dual-cylinder engine operation via multiplexed fiber delivered laser ignition, and sparking with fiber lasers. To the best of our knowledge, each of these accomplishments was a first.

  18. Progress in the indirect-drive National Ignition Campaign

    International Nuclear Information System (INIS)

    Landen, O L; Benedetti, R; Bleuel, D; Bradley, D K; Caggiano, J A; Callahan, D A; Celliers, P M; Cerjan, C J; Clark, D; Collins, G W; Dewald, E L; Dixit, S N; Doeppner, T; Eggert, J; Farley, D; Glenn, S M; Boehly, T R; Edgell, D; Glebov, V; Frenje, J A

    2012-01-01

    We have carried out precision optimization of inertial confinement fusion ignition scale implosions. We have achieved hohlraum temperatures in excess of the 300 eV ignition goal with hot-spot symmetry and shock timing near ignition specs. Using slower rise pulses to peak power and extended pulses resulted in lower hot-spot adiabat and higher main fuel areal density at about 80% of the ignition goal. Yields are within a factor of 5–6 of that required to initiate alpha dominated burn. It is likely we will require thicker shells (+15–20%) to reach ignition velocity without mixing of ablator material into the hot spot. (paper)

  19. Experimental results pertaining to the performance of thermal igniters

    International Nuclear Information System (INIS)

    Carmel, M.K.

    1989-10-01

    This report summarizes the results of various experimental programs regarding the performance of thermal igniters for the deliberate ignition of hydrogen in light water reactors. Experiments involving both premixed combustion and combustion with continuous hydrogen injection are reviewed. Combustion characteristics examined include flammability limits of hydrogen:air and hydrogen:air:steam mixtures, combustion pressure rises, combustion completeness, flame speeds, and heat transfer aspects. Comparisons of igniter type and igniter reliability under simulated reactor accident conditions are included. The results of the research programs provide a broad data base covering nearly all aspects of hydrogen combustion related to the performance of deliberate ignition systems

  20. Continuing bonds and place.

    Science.gov (United States)

    Jonsson, Annika; Walter, Tony

    2017-08-01

    Where do people feel closest to those they have lost? This article explores how continuing bonds with a deceased person can be rooted in a particular place or places. Some conceptual resources are sketched, namely continuing bonds, place attachment, ancestral places, home, reminder theory, and loss of place. The authors use these concepts to analyze interview material with seven Swedes and five Britons who often thought warmly of the deceased as residing in a particular place and often performing characteristic actions. The destruction of such a place, by contrast, could create a troubling, haunting absence, complicating the deceased's absent-presence.

  1. Ignition of Cellulosic Paper at Low Radiant Fluxes

    Science.gov (United States)

    White, K. Alan

    1996-01-01

    The ignition of cellulosic paper by low level thermal radiation is investigated. Past work on radiative ignition of paper is briefly reviewed. No experimental study has been reported for radiative ignition of paper at irradiances below 10 Watts/sq.cm. An experimental study of radiative ignition of paper at these low irradiances is reported. Experimental parameters investigated and discussed include radiant power levels incident on the sample, the method of applying the radiation (focussed vs. diffuse Gaussian source), the presence and relative position of a separate pilot ignition source, and the effects of natural convection (buoyancy) on the ignition process in a normal gravity environment. It is observed that the incident radiative flux (in W/sq.cm) has the greatest influence on ignition time. For a given flux level, a focussed Gaussian source is found to be advantageous to a more diffuse, lower amplitude, thermal source. The precise positioning of a pilot igniter relative to gravity and to the fuel sample affects the ignition process, but the precise effects are not fully understood. Ignition was more readily achieved and sustained with a horizontal fuel sample, indicating the buoyancy plays a role in the ignition process of cellulosic paper. Smoldering combustion of doped paper samples was briefly investigated, and results are discussed.

  2. Comprehensive study of ignition and combustion of single wooden particles

    DEFF Research Database (Denmark)

    Momenikouchaksaraei, Maryam; Yin, Chungen; Kær, Søren Knudsen

    2013-01-01

    How quickly large biomass particles can ignite and burn out when transported into a pulverized-fuel (pf) furnace and suddenly exposed to a hot gas flow containing oxygen is very important in biomass co-firing design and optimization. In this paper, the ignition and burnout of the largest possible...... for all the test conditions. As the particle is further heated up and the volume-weighted average temperature reaches the onset of rapid decomposition of hemicellulose and cellulose, a secondary homogeneous ignition occurs. The model-predicted ignition delays and burnout times show a good agreement...... with the experimental results. Homogeneous ignition delays are found to scale with specific surface areas while heterogeneous ignition delays show less dependency on the areas. The ignition and burnout are also affected by the process conditions, in which the oxygen concentration is found to have a more pronounced...

  3. Development of a pre-ignition submodel for hydrogen engines

    Energy Technology Data Exchange (ETDEWEB)

    Al-Baghdadi, Sadiq [University of Babylon (Iraq). Dept. of Mechanical Engineering

    2005-10-15

    In hydrogen-fuelled spark ignition engine applications, the onset of pre-ignition remains one of the prime limitations that needs to be addressed to avoid its incidence and achieve superior performance. This paper describes a new pre-ignition submodel for engine modelling codes. The effects of changes in key operating variables, such as compression ratio, spark timing, intake pressure, and temperature on pre-ignition limiting equivalence ratios are established both analytically and experimentally. With the established pre-ignition model, it is possible not only to investigate whether pre-ignition is observed with changing operating and design parameters, but also to evaluate those parameters' effects on the maximum possible pre-ignition intensity. (author)

  4. Ignition characteristics of coal blends in an entrained flow furnace

    Energy Technology Data Exchange (ETDEWEB)

    J. Faundez; B. Arias; F. Rubiera; A. Arenillas; X. Garcia; A.L. Gordon; J.J. Pis [Universidad de Concepcion, Concepcion (Chile)

    2007-09-15

    Ignition tests were carried out on blends of three coals of different rank - subbituminous, high volatile and low volatile bituminous - in two entrained flow reactors. The ignition temperatures were determined from the gas evolution profiles (CO, CO{sub 2}, NO, O{sub 2}), while the mechanism of ignition was elucidated from these profiles and corroborated by high-speed video recording. Under the experimental conditions of high carbon loading, clear interactive effects were observed for all the blends. Ignition of the lower rank coals (subbituminous, high volatile bituminous) enhanced the ignition of the higher rank coal (low volatile bituminous) in the blends. The ignition temperatures of the blends of the low rank coals (subbituminous-high volatile bituminous) were additive. However, for the rest of the blends the ignition temperatures were always closer to the lower rank coal in the blend. 21 refs., 8 figs.

  5. Ignition analysis for burn control and diagnostic developments in ITER

    International Nuclear Information System (INIS)

    Mitarai, O.; Muraoka, K.

    1997-01-01

    The temporal evolutions of the operating point during the ignition access and ignited operation phases are analysed on the basis of zero dimensional (0-D) equations in order to clarify the requirements for safe control of ignited operation and for the development of diagnostic systems in ITER. A stable and safe method of reaching the ignited operating point is identified as the 'higher temperature access' method, being compatible with the H mode power threshold constraints. It is found that the ignition boundary can be experimentally determined by a 'thermonuclear oscillation' of the operating point without knowing the power balance equation. On the other hand, the ignition boundary determined by the power balance equation has a larger error bar depending on the accuracy of the diagnostic system. The plasma waveform response to sudden changes in the various plasma parameters during ignited operation is also calculated, and fusion power regulation is demonstrated by feedback control of the fuelling and auxiliary heating power. (author)

  6. Temperature analysis of laser ignited metalized material using spectroscopic technique

    Science.gov (United States)

    Bassi, Ishaan; Sharma, Pallavi; Daipuriya, Ritu; Singh, Manpreet

    2018-05-01

    The temperature measurement of the laser ignited aluminized Nano energetic mixture using spectroscopy has a great scope in in analysing the material characteristic and combustion analysis. The spectroscopic analysis helps to do in depth study of combustion of materials which is difficult to do using standard pyrometric methods. Laser ignition was used because it consumes less energy as compared to electric ignition but ignited material dissipate the same energy as dissipated by electric ignition and also with the same impact. Here, the presented research is primarily focused on the temperature analysis of energetic material which comprises of explosive material mixed with nano-material and is ignited with the help of laser. Spectroscopy technique is used here to estimate the temperature during the ignition process. The Nano energetic mixture used in the research does not comprise of any material that is sensitive to high impact.

  7. EXPERIMENTS AND COMPUTATIONAL MODELING OF PULVERIZED-COAL IGNITION; FINAL

    International Nuclear Information System (INIS)

    Samuel Owusu-Ofori; John C. Chen

    1999-01-01

    Under typical conditions of pulverized-coal combustion, which is characterized by fine particles heated at very high rates, there is currently a lack of certainty regarding the ignition mechanism of bituminous and lower rank coals as well as the ignition rate of reaction. furthermore, there have been no previous studies aimed at examining these factors under various experimental conditions, such as particle size, oxygen concentration, and heating rate. Finally, there is a need to improve current mathematical models of ignition to realistically and accurately depict the particle-to-particle variations that exist within a coal sample. Such a model is needed to extract useful reaction parameters from ignition studies, and to interpret ignition data in a more meaningful way. The authors propose to examine fundamental aspects of coal ignition through (1) experiments to determine the ignition temperature of various coals by direct measurement, and (2) modeling of the ignition process to derive rate constants and to provide a more insightful interpretation of data from ignition experiments. The authors propose to use a novel laser-based ignition experiment to achieve their first objective. Laser-ignition experiments offer the distinct advantage of easy optical access to the particles because of the absence of a furnace or radiating walls, and thus permit direct observation and particle temperature measurement. The ignition temperature of different coals under various experimental conditions can therefore be easily determined by direct measurement using two-color pyrometry. The ignition rate-constants, when the ignition occurs heterogeneously, and the particle heating rates will both be determined from analyses based on these measurements

  8. Assessing the prospects for achieving double-shell ignition on the National Ignition Facility using vacuum hohlraums

    International Nuclear Information System (INIS)

    Amendt, Peter; Cerjan, C.; Hamza, A.; Hinkel, D. E.; Milovich, J. L.; Robey, H. F.

    2007-01-01

    The goal of demonstrating ignition on the National Ignition Facility [J. D. Lindl et al., Phys. Plasmas 11, 339 (2003)] has motivated a revisit of double-shell (DS) targets as a complementary path to the cryogenic baseline approach. Expected benefits of DS ignition targets include noncryogenic deuterium-tritium (DT) fuel preparation, minimal hohlraum-plasma-mediated laser backscatter, low threshold-ignition temperatures (≅4 keV) for relaxed hohlraum x-ray flux asymmetry tolerances, and minimal (two-) shock timing requirements. On the other hand, DS ignition presents several formidable challenges, encompassing room-temperature containment of high-pressure DT (≅790 atm) in the inner shell, strict concentricity requirements on the two shells ( 2 nanoporous aerogels with suspended Cu particles. A prototype demonstration of an ignition DS is planned for 2008, incorporating the needed novel nanomaterials science developments and the required fabrication tolerances for a realistic ignition attempt after 2010

  9. My Place Is Not Your Place

    DEFF Research Database (Denmark)

    Zenker, Sebastian; Beckmann, Suzanne C.

    2013-01-01

    Purpose – Cities increasingly compete with each other for attracting tourists, investors, companies, or residents. Marketers therefore focus on establishing the city as a brand, disregarding that the perception and knowledge of a city differ dramatically between the target audiences. Hence, place...... branding should emphasize much more the perceptions of the different target groups and develop strategies for advanced place brand management. The aim of this paper is to assess the important discrepancies between the city brand perceptions of different target groups with the help of network analysis......-ended-question survey with 334 participants. Findings – Structural differences for the city brand perceptions of two different target groups and the differences between perceptions of an external and internal target group are highlighted. The results and the managerial implications for place marketers are discussed...

  10. Utilisation of VOC in Diesel Engines. Ignition and combustion of VOC released in crude oil tankers

    International Nuclear Information System (INIS)

    Melhus, Oeyvin

    2002-01-01

    The emission of VOC (Volatile Organic Compound) is a significant source of hydrocarbon pollution. In Norway, the offshore oil industry represents a major source. This emission represents both an energy loss and an environmental problem. Gas tankers have used boil-off gas from the cargo tanks as fuel for some time. However, for the current VOC project a new fuel injection concept is designed for tankers to take advantage of the energy present in the VOC evaporated from crude oil. The VOC is mixed with inert gas in these tankers, and thus the utilisation of this gas represents new challenges. The VOC project uses the concept of ''Condensate Diesel Process'' with pilot ignition. An experimental study of ignition and combustion of VOC Fuels reported here was initiated by the time it was decided to start a pilot project converting propulsion engines in shuttle tankers to use VOC Fuel. It is an experimental study carried out at the Marine Technology Centre (MTS). The objective was to study ignition and combustion of the chosen process in comparison with an ordinary diesel process. The experimental results have been discussed and compared with theoretical considerations of injection, ignition and combustion. For experiments on combustion, a rapid compression machine ''DyFo'' was redesigned to use VOC Fuel. The DyFo test rig was initially designed to study ignition and early combustion of spark ignited homogeneous gas/air charges. To study the ignition and early combustion of VOC Fuel injected at high pressure and ignited by pilot diesel fuel, a redesign was necessary. An important feature of the DyFo, is the visualisation of the combustion. The advantage of the DyFo test rig over an engine, is its simplicity and controllability. In an engine the visualisation would suffer from combustion deposits disturbing the view through the quartz glasses, making the images more difficult to interpret. The simplicity is on the other side a drawback. Correct thermal conditions inside

  11. Place branding, embeddedness and endogenous rural development

    NARCIS (Netherlands)

    Donner, Mechthild; Horlings, Lummina; Fort, Fatiha; Vellema, Sietze

    2017-01-01

    This article deals with place branding on the regional scale, in the rural context of food and tourism networks in Europe. Place branding is linked to the concepts of endogenous rural development, territory and embeddedness, by analysing how the valorisation of specific rural assets takes shape.

  12. Populated Places of Iowa

    Data.gov (United States)

    Iowa State University GIS Support and Research Facility — This coverage contains points that represent populated places, ie. cities, towns, villages or any other named place where people live. The coverage was developed...

  13. Ignition on the National Ignition Facility: a path towards inertial fusion energy

    International Nuclear Information System (INIS)

    Moses, Edward I.

    2009-01-01

    The National Ignition Facility (NIF), the world's largest and most powerful laser system for inertial confinement fusion (ICF) and experiments studying high-energy-density (HED) science, is nearing completion at Lawrence Livermore National Laboratory (LLNL). NIF, a 192-beam Nd-glass laser facility, will produce 1.8 MJ, 500 TW of light at the third-harmonic, ultraviolet light of 351 nm. The NIF project is scheduled for completion in March 2009. Currently, all 192 beams have been operationally qualified and have produced over 4.0 MJ of light at the fundamental wavelength of 1053 nm, making NIF the world's first megajoule laser. The principal goal of NIF is to achieve ignition of a deuterium-tritium (DT) fuel capsule and provide access to HED physics regimes needed for experiments related to national security, fusion energy and for broader scientific applications. The plan is to begin 96-beam symmetric indirect-drive ICF experiments early in FY2009. These first experiments represent the next phase of the National Ignition Campaign (NIC). This national effort to achieve fusion ignition is coordinated through a detailed plan that includes the science, technology and equipment such as diagnostics, cryogenic target manipulator and user optics required for ignition experiments. Participants in this effort include LLNL, General Atomics, Los Alamos National Laboratory, Sandia National Laboratory and the University of Rochester Laboratory for Energetics (LLE). The primary goal for NIC is to have all of the equipment operational and integrated into the facility soon after project completion and to conduct a credible ignition campaign in 2010. When the NIF is complete, the long-sought goal of achieving self-sustaining nuclear fusion and energy gain in the laboratory will be much closer to realization. Successful demonstration of ignition and net energy gain on NIF will be a major step towards demonstrating the feasibility of inertial fusion energy (IFE) and will likely focus

  14. Ignition on the National Ignition Facility: a path towards inertial fusion energy

    Science.gov (United States)

    Moses, Edward I.

    2009-10-01

    The National Ignition Facility (NIF), the world's largest and most powerful laser system for inertial confinement fusion (ICF) and experiments studying high-energy-density (HED) science, is nearing completion at Lawrence Livermore National Laboratory (LLNL). NIF, a 192-beam Nd-glass laser facility, will produce 1.8 MJ, 500 TW of light at the third-harmonic, ultraviolet light of 351 nm. The NIF project is scheduled for completion in March 2009. Currently, all 192 beams have been operationally qualified and have produced over 4.0 MJ of light at the fundamental wavelength of 1053 nm, making NIF the world's first megajoule laser. The principal goal of NIF is to achieve ignition of a deuterium-tritium (DT) fuel capsule and provide access to HED physics regimes needed for experiments related to national security, fusion energy and for broader scientific applications. The plan is to begin 96-beam symmetric indirect-drive ICF experiments early in FY2009. These first experiments represent the next phase of the National Ignition Campaign (NIC). This national effort to achieve fusion ignition is coordinated through a detailed plan that includes the science, technology and equipment such as diagnostics, cryogenic target manipulator and user optics required for ignition experiments. Participants in this effort include LLNL, General Atomics, Los Alamos National Laboratory, Sandia National Laboratory and the University of Rochester Laboratory for Energetics (LLE). The primary goal for NIC is to have all of the equipment operational and integrated into the facility soon after project completion and to conduct a credible ignition campaign in 2010. When the NIF is complete, the long-sought goal of achieving self-sustaining nuclear fusion and energy gain in the laboratory will be much closer to realization. Successful demonstration of ignition and net energy gain on NIF will be a major step towards demonstrating the feasibility of inertial fusion energy (IFE) and will likely focus

  15. Test report for core drilling ignitability testing

    International Nuclear Information System (INIS)

    Witwer, K.S.

    1996-01-01

    Testing was carried out with the cooperation of Westinghouse Hanford Company and the United States Bureau of Mines at the Pittsburgh Research Center in Pennsylvania under the Memorandum of Agreement 14- 09-0050-3666. Several core drilling equipment items, specifically those which can come in contact with flammable gasses while drilling into some waste tanks, were tested under conditions similar to actual field sampling conditions. Rotary drilling against steel and rock as well as drop testing of several different pieces of equipment in a flammable gas environment were the specific items addressed. The test items completed either caused no ignition of the gas mixture, or, after having hardware changes or drilling parameters modified, produced no ignition in repeat testing

  16. Fast ignition schemes for inertial confinement fusion

    International Nuclear Information System (INIS)

    Deutsch, C.

    2003-01-01

    The controlled production of a local hot spot in super-compressed deuterium + tritium fuel is examined in details. Relativistic electron beams (REB) in the MeV and proton beams in the few tens MeV energy range produced by PW-lasers are respectively considered. A strong emphasis is given to the propagation issues due to large density gradients in the outer core of compressed fuel. A specific attention is also paid to the final and complete particle stopping resulting in hot spot generation as well as to the interplay of collective vs. particle stopping at the entrance channel on the low density side in plasma target. Moreover, REB production and fast acceleration mechanisms are also given their due attention. Proton fast ignition looks promising as well as the wedged (cone angle) approach circumventing most of transport uncertainties between critical layer and hot spot. Global engineering perspectives for fast ignition scenario (FIS) driven inertial confinement fusion are also detailed. (author)

  17. Ignition system for an internal combustion engine

    Energy Technology Data Exchange (ETDEWEB)

    Imhof, G

    1977-05-12

    The invention pertains to ignition systems for internal combustion engines; in particular, these are used in the engines of modern small motorcycles, where power is supplied by means of a so-called flywheel magneto, so that there is no need for an additional battery. The invention will prevent back-kicking. This is achieved by the following means: in the right direction of rotation of the internal combustion engine, due to an axial magnetic unsymmetry of the rotor, a voltage component that can switch the electronic switch will occur only in one of the two parts of the control winding at the point of ignition. In the wrong direction of rotation, on the other hand, this voltage component will only occur in the other part of the control winding and will act in direction on a diode connected in parallel to this part of the winding.

  18. Integrated thermodynamic model for ignition target performance

    Directory of Open Access Journals (Sweden)

    Springer P.T.

    2013-11-01

    Full Text Available We have derived a 3-dimensional synthetic model for NIF implosion conditions, by predicting and optimizing fits to a broad set of x-ray and nuclear diagnostics obtained on each shot. By matching x-ray images, burn width, neutron time-of-flight ion temperature, yield, and fuel ρr, we obtain nearly unique constraints on conditions in the hotspot and fuel in a model that is entirely consistent with the observables. This model allows us to determine hotspot density, pressure, areal density (ρr, total energy, and other ignition-relevant parameters not available from any single diagnostic. This article describes the model and its application to National Ignition Facility (NIF tritium–hydrogen–deuterium (THD and DT implosion data, and provides an explanation for the large yield and ρr degradation compared to numerical code predictions.

  19. Ignitability and explosibility of gases and vapors

    CERN Document Server

    Ma, Tingguang

    2015-01-01

    The book provides a systematic view on flammability and a collection of solved engineering problems in the fields of dilution and purge, mine gas safety, clean burning safety and gas suppression modeling. For the first time, fundamental principles of energy conservation are used to develop theoretical flammability diagrams and are then explored to understand various safety-related mixing problems. This provides the basis for a fully-analytical solution to any flammability problem. Instead of the traditional view that flammability is a fundamental material property, here flammability is discovered to be a result of the explosibility of air and the ignitability of fuel, or a process property. By exploring the more fundamental concepts of explosibility and ignitability, the safety targets of dilution and purge can be better defined and utilized for guiding safe operations in process safety. This book provides various engineering approaches to mixture flammability, benefiting not only the safety students, but al...

  20. Transport Simulations for Fast Ignition on NIF

    Energy Technology Data Exchange (ETDEWEB)

    Strozzi, D J; Tabak, M; Grote, D P; Cohen, B I; Shay, H D; Town, R J; Kemp, A J; Key, M

    2009-10-26

    We are designing a full hydro-scale cone-guided, indirect-drive FI coupling experiment, for NIF, with the ARC-FIDO short-pulse laser. Current rad-hydro designs with limited fuel jetting into cone tip are not yet adequate for ignition. Designs are improving. Electron beam transport simulations (implicit-PIC LSP) show: (1) Magnetic fields and smaller angular spreads increase coupling to ignition-relevant 'hot spot' (20 um radius); (2) Plastic CD (for a warm target) produces somewhat better coupling than pure D (cryogenic target) due to enhanced resistive B fields; and (3) The optimal T{sub hot} for this target is {approx} 1 MeV; coupling falls by 3x as T{sub hot} rises to 4 MeV.

  1. Radiological assessments for the National Ignition Facility

    International Nuclear Information System (INIS)

    Hong, Kou-John; Lazaro, M.A.

    1996-01-01

    The potential radiological impacts of the National Ignition Facility (NIF), a proposed facility for fusion ignition and high energy density experiments, were assessed for five candidate sites to assist in site selection. The GENII computer program was used to model releases of radionuclides during normal NIF operations and a postulated accident and to calculate radiation doses to the public. Health risks were estimated by converting the estimated doses into health effects using a standard cancer fatality risk factor. The greatest calculated radiation dose was less than one thousandth of a percent of the dose received from natural background radiation; no cancer fatalities would be expected to occur in the public as the result of normal operations. The highest dose conservatively estimated to result from a postulated accident could lead to one in one million risk of cancer

  2. Activation analysis of the compact ignition tokamak

    International Nuclear Information System (INIS)

    Selcow, E.C.

    1986-01-01

    The US fusion program has completed the conceptual design of a compact tokamak device that achieves ignition. The high neutron wall loadings associated with this compact deuterium-tritium-burning device indicate that radiation-related issues may be significant considerations in the overall system design. Sufficient shielding will be requied for the radiation protection of both reactor components and occupational personnel. A close-in igloo shield has been designed around the periphery of the tokamak structure to permit personnel access into the test cell after shutdown and limit the total activation of the test cell components. This paper describes the conceptual design of the igloo shield system and discusses the major neutronic concerns related to the design of the Compact Ignition Tokamak

  3. The physics basis for ignition using indirect-drive targets on the National Ignition Facility

    International Nuclear Information System (INIS)

    Lindl, John D.; Amendt, Peter; Berger, Richard L.; Glendinning, S. Gail; Glenzer, Siegfried H.; Haan, Steven W.; Kauffman, Robert L.; Landen, Otto L.; Suter, Laurence J.

    2004-01-01

    The 1990 National Academy of Science final report of its review of the Inertial Confinement Fusion Program recommended completion of a series of target physics objectives on the 10-beam Nova laser at the Lawrence Livermore National Laboratory as the highest-priority prerequisite for proceeding with construction of an ignition-scale laser facility, now called the National Ignition Facility (NIF). These objectives were chosen to demonstrate that there was sufficient understanding of the physics of ignition targets that the laser requirements for laboratory ignition could be accurately specified. This research on Nova, as well as additional research on the Omega laser at the University of Rochester, is the subject of this review. The objectives of the U.S. indirect-drive target physics program have been to experimentally demonstrate and predictively model hohlraum characteristics, as well as capsule performance in targets that have been scaled in key physics variables from NIF targets. To address the hohlraum and hydrodynamic constraints on indirect-drive ignition, the target physics program was divided into the Hohlraum and Laser-Plasma Physics (HLP) program and the Hydrodynamically Equivalent Physics (HEP) program. The HLP program addresses laser-plasma coupling, x-ray generation and transport, and the development of energy-efficient hohlraums that provide the appropriate spectral, temporal, and spatial x-ray drive. The HEP experiments address the issues of hydrodynamic instability and mix, as well as the effects of flux asymmetry on capsules that are scaled as closely as possible to ignition capsules (hydrodynamic equivalence). The HEP program also addresses other capsule physics issues associated with ignition, such as energy gain and energy loss to the fuel during implosion in the absence of alpha-particle deposition. The results from the Nova and Omega experiments approach the NIF requirements for most of the important ignition capsule parameters, including

  4. A mechanistic approach to safe igniter implementation for hydrogen mitigation

    International Nuclear Information System (INIS)

    Breitung, W.; Dorofeev, S.B.; Travis, J.R.

    1997-01-01

    A new methodology for safe igniter implementation in a full-scale 3-d containment is described. The method consists of the following steps: determination of bounding H 2 /steam sources; high-resolution analysis of the 3-d transport and mixing processes; evaluation of the detonation potential at the time of ignition; optimization of the igniter system such that only early ignition and nonenergetic combustion occurs; and modelling of the continuous deflagration processes during H 2 -release. The method was implemented into the GASFLOW code. The principle and the feasibility is demonstrated for a single room geometry. A full-scale 3-d reactor case is analyzed without and with deliberate ignition, assuming a severe dry H 2 release sequence (1200 kg). In the unmitigated case significant DDT potential in the whole containment develops, including the possibility of global detonations. The analysis with igniters in different positions predicted deflagration or detonation in the break compartment, depending on the igniter location. Igniter positions were found which lead to early ignition, effective H 2 -removal, and negligible pressure loads. The approach can be used to determine number, position and frequency of a safe igniter system for a given large dry containment. (author)

  5. Heavy ion fusion targets; issues for fast ignition

    International Nuclear Information System (INIS)

    Bangerter, Roger O.

    2014-01-01

    During the last 36 years researchers have suggested and evaluated a large number of target designs for heavy ion inertial fusion. The different target designs can be classified according to their mode of ignition, their method of implosion, and their size. Ignition modes include hot-spot ignition and fast ignition. Methods of implosion include direct drive and indirect drive. Historically there has been significant work on indirectly driven targets with hot-spot ignition. Recently there has been increasing interest in directly driven targets with ion driven fast ignition. In principle, fast ignition might lead to improved target performance. On the other hand, fast ignition imposes stringent requirements on accelerators and beam physics. Furthermore, fast ignition magnifies the importance of a number of traditional target physics issues associated with ion beam energy deposition and fuel preheat. This paper will discuss the advantages and disadvantages of the various classes of targets. It will also discuss some issues that must be resolved to assess the feasibility of ion fast ignition

  6. Ignition of a combustible half space

    Science.gov (United States)

    Olmstead, W. E.

    1983-01-01

    A half space of combustible material is subjected to an arbitrary energy flux at the boundary where convection heat loss is also allowed. An asymptotic analysis of the temperature growth reveals two conditions necessary for ignition to occur. Cases of both large and order unity Lewis number are shown to lead to a nonlinear integral equation governing the thermal runaway. Some global and asymptotic properties of the integral equation are obtained.

  7. Prechamber Compression-Ignition Engine Performance

    Science.gov (United States)

    Moore, Charles S; Collins, John H , Jr

    1938-01-01

    Single-cylinder compression-ignition engine tests were made to investigate the performance characteristics of prechamber type of cylinder head. Certain fundamental variables influencing engine performance -- clearance distribution, size, shape, and direction of the passage connecting the cylinder and prechamber, shape of prechamber, cylinder clearance, compression ratio, and boosting -- were independently tested. Results of motoring and of power tests, including several typical indicator cards, are presented.

  8. IGNITION IMPROVEMENT OF LEAN NATURAL GAS MIXTURES

    Energy Technology Data Exchange (ETDEWEB)

    Jason M. Keith

    2005-02-01

    This report describes work performed during a thirty month project which involves the production of dimethyl ether (DME) on-site for use as an ignition-improving additive in a compression-ignition natural gas engine. A single cylinder spark ignition engine was converted to compression ignition operation. The engine was then fully instrumented with a cylinder pressure transducer, crank shaft position sensor, airflow meter, natural gas mass flow sensor, and an exhaust temperature sensor. Finally, the engine was interfaced with a control system for pilot injection of DME. The engine testing is currently in progress. In addition, a one-pass process to form DME from natural gas was simulated with chemical processing software. Natural gas is reformed to synthesis gas (a mixture of hydrogen and carbon monoxide), converted into methanol, and finally to DME in three steps. Of additional benefit to the internal combustion engine, the offgas from the pilot process can be mixed with the main natural gas charge and is expected to improve engine performance. Furthermore, a one-pass pilot facility was constructed to produce 3.7 liters/hour (0.98 gallons/hour) DME from methanol in order to characterize the effluent DME solution and determine suitability for engine use. Successful production of DME led to an economic estimate of completing a full natural gas-to-DME pilot process. Additional experimental work in constructing a synthesis gas to methanol reactor is in progress. The overall recommendation from this work is that natural gas to DME is not a suitable pathway to improved natural gas engine performance. The major reasons are difficulties in handling DME for pilot injection and the large capital costs associated with DME production from natural gas.

  9. Investigating antennas as ignition aid for automotive HID lamps

    International Nuclear Information System (INIS)

    Bergner, A; Engelhardt, M; Bienholz, S; Ruhrmann, C; Hoebing, T; Groeger, S; Mentel, J; Awakowicz, P

    2015-01-01

    This paper considers the ignition of mercury-free high-intensity discharge (HID) lamps for car headlights. Due to safety reasons, these lamps need to have a fast run-up phase which is ensured, amongst other things, by a high Xe pressure of roughly 15 bar (cold) in the discharge vessel. The high Xe pressure causes an increased ignition voltage compared with former mercury-containing automotive HID lamps or low-pressure lamps used for general-lighting applications. The increase in ignition voltage can be limited if the electric field in front of the electrodes is raised by an uplifting of the electrical conductivity along the outer wall of the inner bulb either by a conductive layer on its surface or by a dielectric barrier discharge (DBD) within the outer bulb. This paper considers on the one hand conventional antennas deposited by physical vapour deposition (PVD) and on the other hand a combination of these antennas with a DBD within the outer-bulb operated in 100 mbar Ar as ignition aids. In both cases the antenna potential and antenna width are varied. Additionally, the effects of antenna thickness and antenna material are investigated. The ignition voltage, ignition current and light emission during ignition are measured on a nanosecond timescale. Furthermore, for the very first time, the ignition process is recorded in four consecutive intensified charge-coupled device images using a high-speed camera system with a time resolution in the range of nanoseconds. It was found that antennas strongly reduce the ignition voltage of automotive HID lamps. Active antennas reduce the ignition voltage significantly more than passive antennas, proportional to the conductance of the antenna. Combining conventional antennas with an outer-bulb discharge reduces the ignition voltage from 19 kV without any ignition aid to the intrinsic ignition voltage of the lamp below 10 kV, in the best case. (paper)

  10. The importance of places and place branding

    NARCIS (Netherlands)

    Kovács, Z.; Musterd, S.; Musterd, S.; Kovács, Z.

    2013-01-01

    In the analytical part of this study, we highlight that, despite globalisation and growing uniformity, there is still an important role for place itself in the location decisions of economic players. Part III of this volume deals with this. Even though city-regions across the world have become

  11. A woman's rightful place?

    Science.gov (United States)

    1993-04-01

    Rural development projects in sub-Saharan Africa tend not to succeed because they do not consider women's role and their significance, even though women constitute 70% of agricultural workers, 80% of food producers, 100% of people who prepare meals, and 60-90% do food marketing. Development specialists ignore women because they are not involved in political activities and in decision making. As long as women and women's contributions are not considered, rural development projects will remain inefficient and development will not take place. Thus, projects must include women as agents and beneficiaries of development in key sectors of the economy. Rural development specialists must also consider the effect male labor emigration has on rural women. For example, drought has forced many men to leave their villages, leaving a work force consisting of 95% women to fight desertification. All too often, women have no or limited land ownership rights, thereby keeping them from improving the land, e.g., planting perennial fruit crops. They also tend to be hired hands rather than food producers. They cannot obtain bank loans because they do not own land, and because they are often illiterate (over 90% female illiteracy in 28 African countries), they can neither understand nor complete bank loan forms. Rural development projects further alienate women by aiming training programs to men or by using male agricultural extension agents. Women react to this alienation by rejecting projects that do not benefit them and follow more profitable activities which sometimes interfere with projects. Thus, rural development programs need to invest in women to ensure viable and efficient sustainable development.

  12. The national ignition facility performance status

    Energy Technology Data Exchange (ETDEWEB)

    Haynam, C.; Auerbach, J.; Bowers, M.; Di-Nicola, J.M.; Dixit, S.; Erbert, G.; Heestand, G.; Henesian, M.; Jancaitis, K.; Manes, K.; Marshall, C.; Mehta, N.; Nostrand, M.; Orth, C.; Sacks, R.; Shaw, M.; Sutton, S.; Wegner, P.; Williams, W.; Widmayer, C.; White, R.; Yang, S.; Van Wonterghem, B. [Lawrence Livermore National Laboratory, Livermore, CA (United States)

    2006-06-15

    The National Ignition Facility (NIF) laser has been designed to support high energy density science, including the demonstration of fusion ignition through Inertial Confinement. NIF operated a single 'quad' of 4 beams from December 2002 through October 2004 in order to gain laser operations experience, support target experiments, and demonstrate laser performance consistent with NIF's design requirement. During this two-year period, over 400 Main Laser shots were delivered at 1{omega} to calorimeters for diagnostic calibration purposes, at 3{omega} to the Target Chamber, and at 1{omega}, 2{omega}, and 3{omega} to the precision diagnostic system (PDS). The PDS includes its own independent single beam transport system, NIF design frequency conversion hardware and optics, and laser sampling optics that deliver light to a broad range of laser diagnostics. Highlights of NIF laser performance will be discussed including the results of high energy 2{omega} and 3{omega} experiments, the use of multiple focal spot beam conditioning techniques, the reproducibility of laser performance on multiple shots, the generation on a single beam of a 3{omega} temporally shaped ignition pulse at full energy and power, and recent results on full bundle (8 beamline) performance. NIF's first quad laser performance meets or exceeds NIF's design requirements. (authors)

  13. The National Ignition Facility Performance Status

    Energy Technology Data Exchange (ETDEWEB)

    Haynam, C; Auerbach, J; Nicola, J D; Dixit, S; Heestand, G; Henesian, M; Jancaitis, K; Manes, K; Marshall, C; Mehta, N; Nostrand, M; Orth, C; Sacks, R; Shaw, M; Sutton, S; Wegner, P; Williams, W; Widmayer, C; White, R; Yang, S; Van Wonterghem, B

    2005-08-30

    The National Ignition Facility (NIF) laser has been designed to support high energy density science (HEDS), including the demonstration of fusion ignition through Inertial Confinement. NIF operated a single ''quad'' of 4 beams from December 2002 through October 2004 in order to gain laser operations experience, support target experiments, and demonstrate laser performance consistent with NIF's design requirement. During this two-year period, over 400 Main Laser shots were delivered at 1{omega} to calorimeters for diagnostic calibration purposes, at 3{omega} to the Target Chamber, and at 1{omega}, 2{omega}, and 3{omega} to the Precision Diagnostics System (PDS). The PDS includes its own independent single beam transport system, NIF design frequency conversion hardware and optics, and laser sampling optics that deliver light to a broad range of laser diagnostics. Highlights of NIF laser performance will be discussed including the results of high energy 2{omega} and 3{omega} experiments, the use of multiple focal spot beam conditioning techniques, the reproducibility of laser performance on multiple shots, the generation on a single beam of a 3{omega} temporally shaped ignition pulse at full energy and power, and recent results on full bundle (8 beamline) performance. NIF's first quad laser performance meets or exceeds NIF's design requirements.

  14. Innovative ICF scheme-impact fast ignition

    International Nuclear Information System (INIS)

    Murakami, M.; Nagatomo, H.; Sakaiya, T.; Karasik, M.; Gardner, J.; Bates, J.

    2007-01-01

    A totally new ignition scheme for ICF, impact fast ignition (IFI), is proposed [1], in which the compressed DT main fuel is to be ignited by impact collision of another fraction of separately imploded DT fuel, which is accelerated in the hollow conical target. Two-dimensional hydrodynamic simulation results in full geometry are presented, in which some key physical parameters for the impact shell dynamics such as 10 8 cm/s of the implosion velocity, 200- 300 g/cm 3 of the compressed density, and the converted temperature beyond 5 keV are demonstrated. As the first step toward the proof-of-principle of IFI, we have conducted preliminary experiments under the operation of GEKKO XII/HYPER laser system to achieve a hyper-velocity of the order of 108 cm/s. As a result we have observed a highest velocity, 6.5 x 10 7 cm/s, ever achieved. Furthermore, we have also done the first integrated experiments using the target and observed substantial amount of neutron yields. Reference: [1] M. Murakami and Nagatomo, Nucl. Instrum. Meth. Phys. Res. A 544(2005) 67

  15. Ultrasonically triggered ignition at liquid surfaces.

    Science.gov (United States)

    Simon, Lars Hendrik; Meyer, Lennart; Wilkens, Volker; Beyer, Michael

    2015-01-01

    Ultrasound is considered to be an ignition source according to international standards, setting a threshold value of 1mW/mm(2) [1] which is based on theoretical estimations but which lacks experimental verification. Therefore, it is assumed that this threshold includes a large safety margin. At the same time, ultrasound is used in a variety of industrial applications where it can come into contact with explosive atmospheres. However, until now, no explosion accidents have been reported in connection with ultrasound, so it has been unclear if the current threshold value is reasonable. Within this paper, it is shown that focused ultrasound coupled into a liquid can in fact ignite explosive atmospheres if a specific target positioned at a liquid's surface converts the acoustic energy into a hot spot. Based on ignition tests, conditions could be derived that are necessary for an ultrasonically triggered explosion. These conditions show that the current threshold value can be significantly augmented. Copyright © 2014 Elsevier B.V. All rights reserved.

  16. Opportunities for Integrated Fast Ignition program

    International Nuclear Information System (INIS)

    Mackinnon, A. J.; Key, M. H.; Hatchett, S. P.; Tabak, M.; Town, R.; Gregori, G.; Patel, P. K.; Snavely, R.; Freeman, R. R.; Stephens, R. B.; Beg, F.

    2005-01-01

    Experiments designed to investigate the physics of particle transport and heating of dense plasmas have been carried out in an number of facilities around the world since the publication of the fast ignition concept in 1997. To date a number of integrated experiments, examining the capsule implosion and subsequent heating have been carried out on the Gekko facility at the Institute of Laser Engineering (ILE) Osaka, Japan. The coupling of energy by the short pulse into the pre-compressed core in these experiments was very encouraging. More facilities capable of carrying out integrated experiments are currently under construction: Firex at ILEm the Omega EP facility at the University of Rochester, Z PW at Sandia National Lab, LIL in France and eventually high energy PW beams on the NIF. This presentation will review the current status of experiments in this area and discuss the capabilities of integrated fast ignition research that will be required to design the proof of principle and scaling experiments for fast ignition to be carried on the NIF. (Author)

  17. Laser spark distribution and ignition system

    Science.gov (United States)

    Woodruff, Steven [Morgantown, WV; McIntyre, Dustin L [Morgantown, WV

    2008-09-02

    A laser spark distribution and ignition system that reduces the high power optical requirements for use in a laser ignition and distribution system allowing for the use of optical fibers for delivering the low peak energy pumping pulses to a laser amplifier or laser oscillator. An optical distributor distributes and delivers optical pumping energy from an optical pumping source to multiple combustion chambers incorporating laser oscillators or laser amplifiers for inducing a laser spark within a combustion chamber. The optical distributor preferably includes a single rotating mirror or lens which deflects the optical pumping energy from the axis of rotation and into a plurality of distinct optical fibers each connected to a respective laser media or amplifier coupled to an associated combustion chamber. The laser spark generators preferably produce a high peak power laser spark, from a single low power pulse. The laser spark distribution and ignition system has application in natural gas fueled reciprocating engines, turbine combustors, explosives and laser induced breakdown spectroscopy diagnostic sensors.

  18. FABRICATION AND CHARACTERIZATION OF FAST IGNITION TARGETS

    International Nuclear Information System (INIS)

    HILL, D.W; CASTILLO, E; CHEN, K.C; GRANT, S.E; GREENWOOD, A.L; KAAE, J.L; NIKROO, A; PAGUIO, S.P; SHEARER, C; SMITH, J.N Jr.; STEPHENS, R.B; STEINMAN, D.A; WALL, J.

    2003-09-01

    OAK-B135 Fast ignition is a novel scheme for achieving laser fusion. A class of these targets involves cone mounted CH shells. The authors have been fabricating such targets with shells with a wide variety of diameters and wall thicknesses for several years at General Atomics. In addition, recently such shells were needed for implosion experiments at Laboratory for Laser Energetics (LLE) that for the first time were required to be gas retentive. Fabrication of these targets requires producing appropriate cones and shells, assembling the targets, and characterization of the assembled targets. The cones are produced using micromachining and plating techniques. The shells are fabricated using the depolymerizable mandrel technique followed by micromachining a hole for the cone. The cone and the shell then need to be assembled properly for gas retention and precisely in order to position the cone tip at the desired position within the shell. Both are critical for the fast ignition experiments. The presence of the cone in the shell creates new challenges in characterization of the assembled targets. Finally, for targets requiring a gas fill, the cone-shell assembly needs to be tested for gas retention and proper strength at the glue joint. This paper presents an overview of the developmental efforts and technical issues addressed during the fabrication of fast ignition targets

  19. Dopant-induced ignition of helium nanoplasmas—a mechanistic study

    Science.gov (United States)

    Heidenreich, Andreas; Schomas, Dominik; Mudrich, Marcel

    2017-12-01

    Helium (He) nanodroplets irradiated by intense near-infrared laser pulses form a nanoplasma by avalanche-like electron impact ionizations (EIIs) even at lower laser intensities where He is not directly field ionized, provided that the droplets contain a few dopant atoms which provide seed electrons for the EII avalanche. In this theoretical paper on calcium and xenon doped He droplets we elucidate the mechanism which induces ionization avalanches, termed ignition. We find that the partial loss of seed electrons from the activated droplets starkly assists ignition, as the Coulomb barrier for ionization of helium is lowered by the electric field of the dopant cations, and this deshielding of the cation charges enhances their electric field. In addition, the dopant ions assist the acceleration of the seed electrons (slingshot effect) by the laser field, supporting EIIs of He and also causing electron loss by catapulting electrons away. The dopants’ ability to lower the Coulomb barriers at He as well as the slingshot effect decrease with the spatial expansion of the dopant, causing a dependence of the dopants’ ignition capability on the dopant mass. Here, we develop criteria (impact count functions) to assess the ignition capability of dopants, based on (i) the spatial overlap of the seed electron cloud with the He atoms and (ii) the overlap of their kinetic energy distribution with the distribution of Coulomb barrier heights at He. The relatively long time delays between the instants of dopant ionization and ignition (incubation times) for calcium doped droplets are determined to a large extent by the time it takes to deshield the dopant ions.

  20. Effect of oxygen content on n-heptane auto-ignition characteristics in a HCCI engine

    International Nuclear Information System (INIS)

    Wu, Zhijun; Kang, Zhe; Deng, Jun; Hu, Zongjie; Li, Liguang

    2016-01-01

    Highlights: • n-Heptane HCCI combustion under air and oxygen intake was compared. • n-Heptane auto-ignition postponed due to higher specific heat capacity as oxygen increase. • The increment of heat release fraction during low temperature reaction is studied. • Oxygen enrichment lead to suppressed negative temperature coefficient. • The mechanism of low temperature reaction enhancement as oxygen increase is investigated. - Abstract: To take maximum advantage of the high efficiency of homogeneous charge compression ignition combustion mode and internal combustion Rankine cycle concept, in this study, the n-heptane auto-ignition characteristics have been investigated using a compression ignition internal combustion Rankine cycle engine test bench and a zero-dimensional thermodynamic model coupled with a detailed kinetic model. The n-heptane auto-ignition process shows that under both air and oxygen intake, a typical two-stage combustion in which oxygen enrichment has very minor effects on the n-heptane high temperature reaction. The higher specific heat capacity of oxygen compared with nitrogen leads to an overall increased specific heat capacity, which lowers the in-cylinder temperature during compression stroke, thereby delaying the low temperature reaction initial timing. The higher oxygen content also improves the H-atom abstraction, first O_2 addition, second O_2 addition and peroxyalkylhydroperoxide isomerization, thereby improving the overall reaction rate and the heat release fraction of low temperature reaction. As a result, the in-cylinder temperature at the end of low temperature reaction also increases, thereby shortening significantly the negative temperature coefficient duration compared with a combustion cycle using air as oxidizer.

  1. Taking warfarin (Coumadin)

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/patientinstructions/000292.htm Taking warfarin (Coumadin) To use the sharing features on this ... form a clot or have bleeding problems. Taking Warfarin It is important that you take warfarin exactly ...

  2. Take Charge. Take the Test. PSA (:30)

    Centers for Disease Control (CDC) Podcasts

    As part of the Take Charge. Take the Test. campaign, this 30 second PSA encourages African American women to get tested for HIV. Locations for a free HIV test can be found by visiting hivtest.org/takecharge or calling 1-800-CDC-INFO (1-800-232-4636).

  3. Ignition and devolatilization of pulverized coals in lower oxygen content O{sub 2}/CO{sub 2} atmosphere

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Xiaohong; Li, Jing; Liu, Zhaohui; Yang, Ming; Wang, Dingbang; Zheng, Chuguang [Huazhong Univ. of Science and Technology, Wuhan (China). State Key Lab. of Coal Combustion

    2013-07-01

    High speed camera is employed to capture the transient images of the burning particle in a flat-flame entrained flow reactor, some information of the burning particle, such as the optical intensity and the residence time, are obtained through analysis of transient images. The ignition and devolatilization behavior of different rank coals at 1,670, 1,770 and 1,940 K over a range of 2-30% O{sub 2} in both N{sub 2} and CO{sub 2} diluent gases are researched. The results indicate that the laws of ignition and devolatilization of pulverized coals in low oxygen O{sub 2}/CO{sub 2} atmosphere are consistent with the literature, which focus on the environments of high oxygen contents (10-30%) or lower temperate (900-1,500 K). With the gas temperature and oxygen content increased, the ignition delay time and devolatilization time for the lower oxygen content cases decreased for both N{sub 2} and CO{sub 2} atmosphere. With the use CO{sub 2} in place of N{sub 2} in low oxygen content, the ignition delay was retarded and the duration of devolatilization was increased. The effect of CO{sub 2} on coal particle ignition is explained by its higher molar specific heat. And the effect of CO{sub 2} on devolatilization results from its effect on the diffusion rates of volatile fuel and oxygen.

  4. Place in Transition

    DEFF Research Database (Denmark)

    Mikkelsen, Jacob Bjerre; Lange, Ida Sofie Gøtzsche

    from the 'Everyday World'. Within mobilities studies, research has focused on different aspects and consequences of the post-oil society (see Dennis & Urry 2009, Urry 2013). This paper discusses the conception of place within the enclosed 'Oil World' with point of departure in relocation...... and redefinition of oil rigs from an urban design perspective. The paper constitutes a theoretical basis for future design scenarios - exemplified through visionary urban design proposals for a specific site in the city of Esbjerg, Denmark. Relocating rigs to an urban context initiates discussions of conception...... of 'Place' questioning the fixity of 'Place' (Jensen 2010). Scoped through a relational sense of place (Massey 1993) and the potential of exploring new relations between places (Burns & Kahn 2005), the paper challenges the notion of 'Place as God' (Hvattum 2010). These places in transition contest...

  5. Taking climate to the market

    International Nuclear Information System (INIS)

    Boyle, S.

    1998-01-01

    Since the 1997 Kyoto Protocol set binding targets for greenhouse gas reductions, there has been a rapid increase in interest in emissions trading. This is based on the premise that reduction options may be cheaper in countries such as those of eastern Europe and the developing world, than in others such as the USA and Norway. As long as real emission reductions take place, and given that climate change is a global problem, setting up an emissions trading market should provide a much cheaper option than reductions applied solely at a national level. The real prospects for a viable market, what it will look like, and the deals already taking place are examined. (UK)

  6. A Survey of Studies on Ignition and Burn of Inertially Confined Fuels

    Science.gov (United States)

    Atzeni, Stefano

    2016-10-01

    A survey of studies on ignition and burn of inertial fusion fuels is presented. Potentials and issues of different approaches to ignition (central ignition, fast ignition, volume ignition) are addressed by means of simple models and numerical simulations. Both equimolar DT and T-lean mixtures are considered. Crucial issues concerning hot spot formation (implosion symmetry for central ignition; igniting pulse parameters for fast ignition) are briefly discussed. Recent results concerning the scaling of the ignition energy with the implosion velocity and constrained gain curves are also summarized.

  7. A Comparative Study of Cycle Variability of Laser Plug Ignition vs Classical Spark Plug Ignition in Combustion Engines

    Science.gov (United States)

    Done, Bogdan

    2017-10-01

    Over the past 30 years numerous studies and laboratory experiments have researched the use of laser energy to ignite gas and fuel-air mixtures. The actual implementation of this laser application has still to be fully achieved in a commercial automotive application. Laser Plug Ignition as a replacement for Spark Plug Ignition in the internal combustion engines of automotive vehicles, offers several potential benefits such as extending lean burn capability, reducing the cyclic variability between combustion cycles and decreasing the total amount of ignition costs, and implicitly weight and energy requirements. The paper presents preliminary results of cycle variability study carried on a SI Engine equipped with laser Plug Ignition system. Versus classic ignition system, the use of the laser Plug Ignition system assures the reduction of the combustion process variability, reflected in the lower values of the coefficient of variability evaluated for indicated mean effective pressure, maximum pressure, maximum pressure angle and maximum pressure rise rate. The laser plug ignition system was mounted on an experimental spark ignition engine and tested at the regime of 90% load and 2800 rev/min, at dosage of λ=1.1. Compared to conventional spark plug, laser ignition assures the efficiency at lean dosage.

  8. Effect of flow velocity and temperature on ignition characteristics in laser ignition of natural gas and air mixtures

    Science.gov (United States)

    Griffiths, J.; Riley, M. J. W.; Borman, A.; Dowding, C.; Kirk, A.; Bickerton, R.

    2015-03-01

    Laser induced spark ignition offers the potential for greater reliability and consistency in ignition of lean air/fuel mixtures. This increased reliability is essential for the application of gas turbines as primary or secondary reserve energy sources in smart grid systems, enabling the integration of renewable energy sources whose output is prone to fluctuation over time. This work details a study into the effect of flow velocity and temperature on minimum ignition energies in laser-induced spark ignition in an atmospheric combustion test rig, representative of a sub 15 MW industrial gas turbine (Siemens Industrial Turbomachinery Ltd., Lincoln, UK). Determination of minimum ignition energies required for a range of temperatures and flow velocities is essential for establishing an operating window in which laser-induced spark ignition can operate under realistic, engine-like start conditions. Ignition of a natural gas and air mixture at atmospheric pressure was conducted using a laser ignition system utilizing a Q-switched Nd:YAG laser source operating at 532 nm wavelength and 4 ns pulse length. Analysis of the influence of flow velocity and temperature on ignition characteristics is presented in terms of required photon flux density, a useful parameter to consider during the development laser ignition systems.

  9. Laser imprint and implications for direct drive ignition with the National Ignition Facility

    International Nuclear Information System (INIS)

    Weber, S.V.; Glendinning, S.G.; Kalantar, D.H.; Remington, B.A.; Rothenberg, J.E.

    1996-01-01

    For direct drive ICF, nonuniformities in laser illumination can seed ripples at the ablation front in a process called imprint. Such nonuniformities will grow during the capsule implosion and can penetrate the capsule shell impede ignition, or degrade burn. We have simulated imprint for a number of experiments on tile Nova laser. Results are in generally good agreement with experimental data. We leave also simulated imprint upon National Ignition Facility (NIF) direct drive ignition capsules. Imprint modulation amplitude comparable to the intrinsic surface finish of ∼40 nm is predicted for a laser bandwidth of 0.5 THz. Ablation front modulations experience growth factors up to several thousand, carrying modulation well into the nonlinear regime. Saturation modeling predicts that the shell should remain intact at the time of peak velocity, but penetration at earlier times appears more marginal

  10. Fast ignition: Physics progress in the US fusion energy program and prospects for achieving ignition

    International Nuclear Information System (INIS)

    Key, M.; Andersen, C.; Cowan, T.

    2003-01-01

    Fast ignition (FI) has significant potential advantages for inertial fusion energy and it is therefore being studied as an exploratory concept in the US fusion energy program. FI is based on short pulse isochoric heating of pre-compressed DT by intense beams of laser accelerated MeV electrons or protons. Recent experimental progress in the study of these two heating processes is discussed. The goal is to benchmark new models in order to predict accurately the requirements for full-scale fast ignition. An overview is presented of the design and experimental testing of a cone target implosion concept for fast ignition. Future prospects and conceptual designs for larger scale FI experiments using planned high energy petawatt upgrades of major lasers in the US are outlined. A long-term road map for FI is defined. (author)

  11. Experimental investigations of the minimum ignition energy and the minimum ignition temperature of inert and combustible dust cloud mixtures

    International Nuclear Information System (INIS)

    Addai, Emmanuel Kwasi; Gabel, Dieter; Krause, Ulrich

    2016-01-01

    Highlights: • Ignition sensitivity of a highly flammable dust decreases upon addition of inert dust. • Minimum ignition temperature of a highly flammable dust increases when inert concentration increase. • Minimum ignition energy of a highly flammable dust increases when inert concentration increase. • The permissible range for the inert mixture to minimize the ignition risk lies between 60 to 80%. - Abstract: The risks associated with dust explosions still exist in industries that either process or handle combustible dust. This explosion risk could be prevented or mitigated by applying the principle of inherent safety (moderation). This is achieved by adding an inert material to a highly combustible material in order to decrease the ignition sensitivity of the combustible dust. The presented paper deals with the experimental investigation of the influence of adding an inert dust on the minimum ignition energy and the minimum ignition temperature of the combustible/inert dust mixtures. The experimental investigation was done in two laboratory scale equipment: the Hartmann apparatus and the Godbert-Greenwald furnace for the minimum ignition energy and the minimum ignition temperature test respectively. This was achieved by mixing various amounts of three inert materials (magnesium oxide, ammonium sulphate and sand) and six combustible dusts (brown coal, lycopodium, toner, niacin, corn starch and high density polyethylene). Generally, increasing the inert materials concentration increases the minimum ignition energy as well as the minimum ignition temperatures until a threshold is reached where no ignition was obtained. The permissible range for the inert mixture to minimize the ignition risk lies between 60 to 80%.

  12. Experimental investigations of the minimum ignition energy and the minimum ignition temperature of inert and combustible dust cloud mixtures

    Energy Technology Data Exchange (ETDEWEB)

    Addai, Emmanuel Kwasi, E-mail: emmanueladdai41@yahoo.com; Gabel, Dieter; Krause, Ulrich

    2016-04-15

    Highlights: • Ignition sensitivity of a highly flammable dust decreases upon addition of inert dust. • Minimum ignition temperature of a highly flammable dust increases when inert concentration increase. • Minimum ignition energy of a highly flammable dust increases when inert concentration increase. • The permissible range for the inert mixture to minimize the ignition risk lies between 60 to 80%. - Abstract: The risks associated with dust explosions still exist in industries that either process or handle combustible dust. This explosion risk could be prevented or mitigated by applying the principle of inherent safety (moderation). This is achieved by adding an inert material to a highly combustible material in order to decrease the ignition sensitivity of the combustible dust. The presented paper deals with the experimental investigation of the influence of adding an inert dust on the minimum ignition energy and the minimum ignition temperature of the combustible/inert dust mixtures. The experimental investigation was done in two laboratory scale equipment: the Hartmann apparatus and the Godbert-Greenwald furnace for the minimum ignition energy and the minimum ignition temperature test respectively. This was achieved by mixing various amounts of three inert materials (magnesium oxide, ammonium sulphate and sand) and six combustible dusts (brown coal, lycopodium, toner, niacin, corn starch and high density polyethylene). Generally, increasing the inert materials concentration increases the minimum ignition energy as well as the minimum ignition temperatures until a threshold is reached where no ignition was obtained. The permissible range for the inert mixture to minimize the ignition risk lies between 60 to 80%.

  13. Ignition and combustion characteristics of metallized propellants

    Science.gov (United States)

    Turns, Stephen R.; Mueller, D. C.

    1993-01-01

    Experimental and analytical investigations focusing on secondary atomization and ignition characteristics of aluminum/liquid hydrocarbon slurry propellants were conducted. Experimental efforts included the application of a laser-based, two-color, forward-scatter technique to simultaneously measure free-flying slurry droplet diameters and velocities for droplet diameters in the range of 10-200 microns. A multi-diffusion flame burner was used to create a high-temperature environment into which a dilute stream of slurry droplets could be introduced. Narrowband measurements of radiant emission were used to determine if ignition of the aluminum in the slurry droplet had occurred. Models of slurry droplet shell formation were applied to aluminum/liquid hydrocarbon propellants and used to ascertain the effects of solids loading and ultimate particle size on the minimum droplet diameter that will permit secondary atomization. For a 60 weight-percent Al slurry, the limiting critical diameter was predicted to be 34.7 microns which is somewhat greater than the 20-25 micron limiting diameters determined in the experiments. A previously developed model of aluminum ignition in a slurry droplet was applied to the present experiments and found to predict ignition times in reasonable agreement with experimental measurements. A model was also developed that predicts the mechanical stress in the droplet shell and a parametric study was conducted. A one-dimensional model of a slurry-fueled rocket combustion chamber was developed. This model includes the processes of liquid hydrocarbon burnout, secondary atomization, aluminum ignition, and aluminum combustion. Also included is a model for radiant heat transfer from the hot aluminum oxide particles to the chamber walls. Exercising this model shows that only a modest amount of secondary atomization is required to reduce residence times for aluminum burnout, and thereby maintain relatively short chamber lengths. The model also predicts

  14. Short-wavelength and three-dimensional instability evolution in National Ignition Facility ignition capsule designs

    International Nuclear Information System (INIS)

    Clark, D. S.; Haan, S. W.; Cook, A. W.; Edwards, M. J.; Hammel, B. A.; Koning, J. M.; Marinak, M. M.

    2011-01-01

    Ignition capsule designs for the National Ignition Facility (NIF) [G. H. Miller, E. I. Moses, and C. R. Wuest, Opt. Eng. 443, 2841 (2004)] have continued to evolve in light of improved physical data inputs, improving simulation techniques, and, most recently, experimental data from a growing number of NIF sub-ignition experiments. This paper summarizes a number of recent changes to the cryogenic capsule design and some of our latest techniques in simulating its performance. Specifically, recent experimental results indicated harder x-ray drive spectra in NIF hohlraums than were predicted and used in previous capsule optimization studies. To accommodate this harder drive spectrum, a series of high-resolution 2-D simulations, resolving Legendre mode numbers as high as 2000, were run and the germanium dopant concentration and ablator shell thicknesses re-optimized accordingly. Simultaneously, the possibility of cooperative or nonlinear interaction between neighboring ablator surface defects has motivated a series of fully 3-D simulations run with the massively parallel HYDRA code. These last simulations include perturbations seeded on all capsule interfaces and can use actual measured shell surfaces as initial conditions. 3-D simulations resolving Legendre modes up to 200 on large capsule sectors have run through ignition and burn, and higher resolution simulations resolving as high as mode 1200 have been run to benchmark high-resolution 2-D runs. Finally, highly resolved 3-D simulations have also been run of the jet-type perturbation caused by the fill tube fitted to the capsule. These 3-D simulations compare well with the more typical 2-D simulations used in assessing the fill tube's impact on ignition. Coupled with the latest experimental inputs from NIF, our improving simulation capability yields a fuller and more accurate picture of NIF ignition capsule performance.

  15. Implementation of a near backscattering imaging system on the National Ignition Facility

    International Nuclear Information System (INIS)

    Mackinnon, A.J.; McCarville, T.; Piston, K.; Niemann, C.; Jones, G.; Reinbachs, I.; Costa, R.; Celeste, J.; Holtmeier, G.; Griffith, R.; Kirkwood, R.; MacGowan, B.; Glenzer, S.H.; Latta, M.R.

    2004-01-01

    A near backscattering imaging diagnostic system is being implemented on the first quad of beams on the National Ignition Facility. This diagnostic images diffusing scatter plates, placed around the final focus lenses on the National Ignition Facility target chamber, to quantitatively measure the fraction of light backscattered outside of the focusing cone angle of incident laser beam. A wide-angle imaging system relays an image of light scattered outside the lens onto a gated charge coupled device camera, providing 3 mm resolution over a 2 m field of view. To account for changes of the system throughput due to exposure to target debris the system will be routinely calibrated in situ at 532 and 355 nm using a dedicated pulsed laser source

  16. Hot-spot mix in ignition-scale inertial confinement fusion targets.

    Science.gov (United States)

    Regan, S P; Epstein, R; Hammel, B A; Suter, L J; Scott, H A; Barrios, M A; Bradley, D K; Callahan, D A; Cerjan, C; Collins, G W; Dixit, S N; Döppner, T; Edwards, M J; Farley, D R; Fournier, K B; Glenn, S; Glenzer, S H; Golovkin, I E; Haan, S W; Hamza, A; Hicks, D G; Izumi, N; Jones, O S; Kilkenny, J D; Kline, J L; Kyrala, G A; Landen, O L; Ma, T; MacFarlane, J J; MacKinnon, A J; Mancini, R C; McCrory, R L; Meezan, N B; Meyerhofer, D D; Nikroo, A; Park, H-S; Ralph, J; Remington, B A; Sangster, T C; Smalyuk, V A; Springer, P T; Town, R P J

    2013-07-26

    Mixing of plastic ablator material, doped with Cu and Ge dopants, deep into the hot spot of ignition-scale inertial confinement fusion implosions by hydrodynamic instabilities is diagnosed with x-ray spectroscopy on the National Ignition Facility. The amount of hot-spot mix mass is determined from the absolute brightness of the emergent Cu and Ge K-shell emission. The Cu and Ge dopants placed at different radial locations in the plastic ablator show the ablation-front hydrodynamic instability is primarily responsible for hot-spot mix. Low neutron yields and hot-spot mix mass between 34(-13,+50)  ng and 4000(-2970,+17 160)  ng are observed.

  17. Capsule performance optimization in the national ignition campaign

    International Nuclear Information System (INIS)

    Landen, O L; MacGowan, B J; Haan, S W; Edwards, J

    2010-01-01

    A capsule performance optimization campaign will be conducted at the National Ignition Facility [1] to substantially increase the probability of ignition. The campaign will experimentally correct for residual uncertainties in the implosion and hohlraum physics used in our radiation-hydrodynamic computational models before proceeding to cryogenic-layered implosions and ignition attempts. The required tuning techniques using a variety of ignition capsule surrogates have been demonstrated at the Omega facility under scaled hohlraum and capsule conditions relevant to the ignition design and shown to meet the required sensitivity and accuracy. In addition, a roll-up of all expected random and systematic uncertainties in setting the key ignition laser and target parameters due to residual measurement, calibration, cross-coupling, surrogacy, and scale-up errors has been derived that meets the required budget.

  18. Capsule performance optimization in the National Ignition Campaigna)

    Science.gov (United States)

    Landen, O. L.; Boehly, T. R.; Bradley, D. K.; Braun, D. G.; Callahan, D. A.; Celliers, P. M.; Collins, G. W.; Dewald, E. L.; Divol, L.; Glenzer, S. H.; Hamza, A.; Hicks, D. G.; Hoffman, N.; Izumi, N.; Jones, O. S.; Kirkwood, R. K.; Kyrala, G. A.; Michel, P.; Milovich, J.; Munro, D. H.; Nikroo, A.; Olson, R. E.; Robey, H. F.; Spears, B. K.; Thomas, C. A.; Weber, S. V.; Wilson, D. C.; Marinak, M. M.; Suter, L. J.; Hammel, B. A.; Meyerhofer, D. D.; Atherton, J.; Edwards, J.; Haan, S. W.; Lindl, J. D.; MacGowan, B. J.; Moses, E. I.

    2010-05-01

    A capsule performance optimization campaign will be conducted at the National Ignition Facility [G. H. Miller et al., Nucl. Fusion 44, 228 (2004)] to substantially increase the probability of ignition by laser-driven hohlraums [J. D. Lindl et al., Phys. Plasmas 11, 339 (2004)]. The campaign will experimentally correct for residual uncertainties in the implosion and hohlraum physics used in our radiation-hydrodynamic computational models before proceeding to cryogenic-layered implosions and ignition attempts. The required tuning techniques using a variety of ignition capsule surrogates have been demonstrated at the OMEGA facility under scaled hohlraum and capsule conditions relevant to the ignition design and shown to meet the required sensitivity and accuracy. In addition, a roll-up of all expected random and systematic uncertainties in setting the key ignition laser and target parameters due to residual measurement, calibration, cross-coupling, surrogacy, and scale-up errors has been derived that meets the required budget.

  19. Capsule performance optimization in the national ignition campaign

    Science.gov (United States)

    Landen, O. L.; MacGowan, B. J.; Haan, S. W.; Edwards, J.

    2010-08-01

    A capsule performance optimization campaign will be conducted at the National Ignition Facility [1] to substantially increase the probability of ignition. The campaign will experimentally correct for residual uncertainties in the implosion and hohlraum physics used in our radiation-hydrodynamic computational models before proceeding to cryogenic-layered implosions and ignition attempts. The required tuning techniques using a variety of ignition capsule surrogates have been demonstrated at the Omega facility under scaled hohlraum and capsule conditions relevant to the ignition design and shown to meet the required sensitivity and accuracy. In addition, a roll-up of all expected random and systematic uncertainties in setting the key ignition laser and target parameters due to residual measurement, calibration, cross-coupling, surrogacy, and scale-up errors has been derived that meets the required budget.

  20. Capsule performance optimization in the National Ignition Campaign

    International Nuclear Information System (INIS)

    Landen, O. L.; Bradley, D. K.; Braun, D. G.; Callahan, D. A.; Celliers, P. M.; Collins, G. W.; Dewald, E. L.; Divol, L.; Glenzer, S. H.; Hamza, A.; Hicks, D. G.; Izumi, N.; Jones, O. S.; Kirkwood, R. K.; Michel, P.; Milovich, J.; Munro, D. H.; Robey, H. F.; Spears, B. K.; Thomas, C. A.

    2010-01-01

    A capsule performance optimization campaign will be conducted at the National Ignition Facility [G. H. Miller et al., Nucl. Fusion 44, 228 (2004)] to substantially increase the probability of ignition by laser-driven hohlraums [J. D. Lindl et al., Phys. Plasmas 11, 339 (2004)]. The campaign will experimentally correct for residual uncertainties in the implosion and hohlraum physics used in our radiation-hydrodynamic computational models before proceeding to cryogenic-layered implosions and ignition attempts. The required tuning techniques using a variety of ignition capsule surrogates have been demonstrated at the OMEGA facility under scaled hohlraum and capsule conditions relevant to the ignition design and shown to meet the required sensitivity and accuracy. In addition, a roll-up of all expected random and systematic uncertainties in setting the key ignition laser and target parameters due to residual measurement, calibration, cross-coupling, surrogacy, and scale-up errors has been derived that meets the required budget.

  1. Kinetic mechanism of plasma-assisted ignition of hydrocarbons

    International Nuclear Information System (INIS)

    Kosarev, I N; Aleksandrov, N L; Kindysheva, S V; Starikovskaia, S M; Starikovskii, A Yu

    2008-01-01

    Ignition of hydrocarbon-containing gaseous mixtures has been studied experimentally and numerically under the action of a high-voltage nanosecond discharge at elevated temperatures. Ignition delay times were measured behind a reflected shock wave in stoichiometric C n H 2n+2 : O 2 mixtures (10%) diluted with Ar (90%) for n = 1-5. It was shown that the application of the gas discharge leads to more than an order of magnitude decrease in ignition delay time for all hydrocarbons under consideration. The measured values of ignition delay time agree well with the results of a numerical simulation of the ignition based on the calculation of atom and radical production during the discharge and in its afterglow. The analysis of simulation results showed that a non-equilibrium plasma favours the ignition mainly due to O atoms produced in the active phase of the discharge. (fast track communication)

  2. Capsule Performance Optimization in the National Ignition Campaign

    Energy Technology Data Exchange (ETDEWEB)

    Landen, O L; MacGowan, B J; Haan, S W; Edwards, J

    2009-10-13

    A capsule performance optimization campaign will be conducted at the National Ignition Facility to substantially increase the probability of ignition. The campaign will experimentally correct for residual uncertainties in the implosion and hohlraum physics used in our radiation-hydrodynamic computational models before proceeding to cryogenic-layered implosions and ignition attempts. The required tuning techniques using a variety of ignition capsule surrogates have been demonstrated at the Omega facility under scaled hohlraum and capsule conditions relevant to the ignition design and shown to meet the required sensitivity and accuracy. In addition, a roll-up of all expected random and systematic uncertainties in setting the key ignition laser and target parameters due to residual measurement, calibration, cross-coupling, surrogacy, and scale-up errors has been derived that meets the required budget.

  3. Gain curves and hydrodynamic modeling for shock ignition

    International Nuclear Information System (INIS)

    Lafon, M.; Ribeyre, X.; Schurtz, G.

    2010-01-01

    Ignition of a precompressed thermonuclear fuel by means of a converging shock is now considered as a credible scheme to obtain high gains for inertial fusion energy. This work aims at modeling the successive stages of the fuel time history, from compression to final thermonuclear combustion, in order to provide the gain curves of shock ignition (SI). The leading physical mechanism at work in SI is pressure amplification, at first by spherical convergence, and by collision with the shock reflected at center during the stagnation process. These two effects are analyzed, and ignition conditions are provided as functions of the shock pressure and implosion velocity. Ignition conditions are obtained from a non-isobaric fuel assembly, for which we present a gain model. The corresponding gain curves exhibit a significantly lower ignition threshold and higher target gains than conventional central ignition.

  4. Place-Specific Computing

    DEFF Research Database (Denmark)

    Messeter, Jörn

    2009-01-01

    An increased interest in the notion of place has evolved in interaction design based on the proliferation of wireless infrastructures, developments in digital media, and a ‘spatial turn’ in computing. In this article, place-specific computing is suggested as a genre of interaction design that add......An increased interest in the notion of place has evolved in interaction design based on the proliferation of wireless infrastructures, developments in digital media, and a ‘spatial turn’ in computing. In this article, place-specific computing is suggested as a genre of interaction design...... that addresses the shaping of interactions among people, place-specific resources and global socio-technical networks, mediated by digital technology, and influenced by the structuring conditions of place. The theoretical grounding for place-specific computing is located in the meeting between conceptions...... of place in human geography and recent research in interaction design focusing on embodied interaction. Central themes in this grounding revolve around place and its relation to embodiment and practice, as well as the social, cultural and material aspects conditioning the enactment of place. Selected...

  5. The National Ignition Facility. The path to ignition and inertial fusion energy

    International Nuclear Information System (INIS)

    Eric Storm

    2010-01-01

    Complete text of publication follows. The National Ignition Facility (NIF), the world's largest and most energetic laser system built for studying inertial confinement fusion (ICF) and high-energy-density (HED) science, is now operational at Lawrence Livermore National Laboratory (LLNL). NIF's 192 beams are capable of producing 1.8 MJ and 500 TW of ultraviolet light and are configured to create pressures as high as 100 GB, matter temperatures approaching 10 9 and densities over 1000 g/cm 3 . With these capabis70lities, the NIF will enable exploring scientific problems in strategic defense, basic science and fusion energy. One of the early NIF campaigns is focusing on demonstrating laboratory-scale thermonuclear ignition and burn to produce net fusion energy gains of 10-20 with 1.2 to 1.4 MJ of 0.35 μm light. NIF ignition experiments began late in FY2009 as part of the National Ignition Campaign (NIC). Participants of NIC include LLNL, General Atomics, Los Alamos National Laboratory, Sandia National Laboratory, and the University of Rochester Laboratory for Energetics (LLE) as well as variety of national and international collaborators. The results from these initial experiments show great promise for the relatively near-term achievement of ignition. Capsule implosion experiments at energies up to 1.2 MJ have demonstrated laser energetics, radiation temperatures, and symmetry control that scale to ignition conditions. Of particular importance is the demonstration of peak hohlraum temperatures near 300 eV with low overall backscatter less than 10%. Cryogenic target capability and additional diagnostics are being installed in preparation for layered target deuterium-tritium implosions to be conducted later in 2010. The goal for NIC is to demonstrate a predictable fusion experimental platform by the end of 2012. Successful demonstration of ignition and net energy gain on NIF will be a major step towards demonstrating the feasibility of Inertial Fusion Energy (IFE) and

  6. From sense of place to visualization of place: examining people-place relationships for insight on developing geovisualizations.

    Science.gov (United States)

    Newell, Robert; Canessa, Rosaline

    2018-02-01

    Effective resource planning incorporates people-place relationships, allowing these efforts to be inclusive of the different local beliefs, interests, activities and needs. 'Geovisualizations' can serve as potentially powerful tools for facilitating 'place-conscious' resource planning, as they can be developed with high degrees of realism and accuracy, allowing people to recognize and relate to them as 'real places'. However, little research has been done on this potential, and the place-based applications of these visual tools are poorly understood. This study takes steps toward addressing this gap by exploring the relationship between sense of place and 'visualization of place'. Residents of the Capital Regional District of BC, Canada, were surveyed about their relationship with local coastal places, concerns for the coast, and how they mentally visualize these places. Factor analysis identified four sense of place dimensions - nature protection values, community and economic well-being values, place identity and place dependence, and four coastal concerns dimensions - ecological, private opportunities, public space and boating impacts. Visualization data were coded and treated as dependent variables in a series of logistic regressions that used sense of place and coastal concerns dimensions as predictors. Results indicated that different aspects of sense of place and (to a lesser degree) concerns for places influence the types of elements people include in their mental visualization of place. In addition, sense of place influenced the position and perspective people assume in these visualizations. These findings suggest that key visual elements and perspectives speak to different place relationships, which has implications for developing and using geovisualizations in terms of what elements should be included in tools and (if appropriate) depicted as affected by potential management or development scenarios.

  7. Internal combustion engine report: Spark ignited ICE GenSet optimization and novel concept development

    Energy Technology Data Exchange (ETDEWEB)

    Keller, J.; Blarigan, P. Van [Sandia National Labs., Livermore, CA (United States)

    1998-08-01

    In this manuscript the authors report on two projects each of which the goal is to produce cost effective hydrogen utilization technologies. These projects are: (1) the development of an electrical generation system using a conventional four-stroke spark-ignited internal combustion engine generator combination (SI-GenSet) optimized for maximum efficiency and minimum emissions, and (2) the development of a novel internal combustion engine concept. The SI-GenSet will be optimized to run on either hydrogen or hydrogen-blends. The novel concept seeks to develop an engine that optimizes the Otto cycle in a free piston configuration while minimizing all emissions. To this end the authors are developing a rapid combustion homogeneous charge compression ignition (HCCI) engine using a linear alternator for both power take-off and engine control. Targeted applications include stationary electrical power generation, stationary shaft power generation, hybrid vehicles, and nearly any other application now being accomplished with internal combustion engines.

  8. Management and communication courses – Places available

    CERN Multimedia

    2012-01-01

    There are places available in some management and communication courses taking place in the period January to March 2013.   For more information on the course, click on the course title, which will bring you to the training catalogue. You can then sign-up on-line. For advice, you can contact: Erwin Mosselmans, tel. 74125, erwin.mosselmans@cern.ch Nathalie Dumeaux, tel. 78144, nathalie.dumeaux@cern.ch Courses in English (or bilingual) Session Duration Language Availability How to get, as a supervisor, the most out of the annual interview 21 January 1 day English 2 places Project Engineering 24 and 25 January 2 days English 6 places How to get, as a supervisor, the most out of the annual interview 31 January 1 day English 6 places Conflict Resolution for Managers 19 and 20 February 2 days English One more place Project Scheduling & Costing 6 and 7 March 2 days English 2 places Communicati...

  9. Hydrodynamic modeling and simulations of shock ignition thresholds

    Directory of Open Access Journals (Sweden)

    Lafon M.

    2013-11-01

    Full Text Available The Shock Ignition (SI scheme [1] offers to reduce the laser requirements by relaxing the implosion phase to sub-ignition velocities and later adding an intense laser spike. Depending on laser energy, target characteristics and implosion velocity, high gains are expected [2,3]. Relevant intensities for scaled targets imploded in the velocity range from 150 to 400 km/s are defined at ignition thresholds. A range of moderate implosion velocities is specified to match safe implosions. These conditions for target design are then inferred for relevant NIF and LMJ shock-ignited targets.

  10. Review of the National Ignition Campaign 2009-2012

    International Nuclear Information System (INIS)

    Lindl, John; Landen, Otto; Edwards, John; Moses, Ed

    2014-01-01

    The National Ignition Campaign (NIC) was a multi-institution effort established under the National Nuclear Security Administration of DOE in 2005, prior to the completion of the National Ignition Facility (NIF) in 2009. The scope of the NIC was the planning and preparation for and the execution of the first 3 yr of ignition experiments (through the end of September 2012) as well as the development, fielding, qualification, and integration of the wide range of capabilities required for ignition. Besides the operation and optimization of the use of NIF, these capabilities included over 50 optical, x-ray, and nuclear diagnostic systems, target fabrication facilities, experimental platforms, and a wide range of NIF facility infrastructure. The goal of ignition experiments on the NIF is to achieve, for the first time, ignition and thermonuclear burn in the laboratory via inertial confinement fusion and to develop a platform for ignition and high energy density applications on the NIF. The goal of the NIC was to develop and integrate all of the capabilities required for a precision ignition campaign and, if possible, to demonstrate ignition and gain by the end of FY12. The goal of achieving ignition can be divided into three main challenges. The first challenge is defining specifications for the target, laser, and diagnostics with the understanding that not all ignition physics is fully understood and not all material properties are known. The second challenge is designing experiments to systematically remove these uncertainties. The third challenge is translating these experimental results into metrics designed to determine how well the experimental implosions have performed relative to expectations and requirements and to advance those metrics toward the conditions required for ignition. This paper summarizes the approach taken to address these challenges, along with the progress achieved to date and the challenges that remain. At project completion in 2009, NIF lacked

  11. An assessment of two off-shore igniter concepts

    International Nuclear Information System (INIS)

    Guenette, C. C.

    1997-01-01

    On June 12, 1996, two controlled in-situ oil spill burns (ISB), using a response-prepared ISB system, were conducted in the North Sea, 40 miles off the U. K. coast. The first burn involved fresh crude oil and was ignited with a hand-held igniter using a standard gelled fuel mixture. In the second burn an emulsified crude was used, ignited with a prototype emulsion breaking igniter (EBI) deployed using the Helitorch. The objective was to determine operational practicalities under realistic conditions when responding to a weathered oil situation in an offshore location. This paper is devoted to an assessment of the two igniter systems used during the trials. Results showed that oil aged by 12 hours with a 25 per cent water content burned down to a three-to-four per cent residue. The fire burn survived the two burns intact. The hand-held ignition system worked with fresh oil and the Helitorch lit emulsified oil using EBI. These trials were the first time that the EBI was deployed from a Helitorch slung beneath a helicopter. It was concluded that (1) the simplicity of the logistics required for the hand-held igniter would favour its use over the Helitorch method for fresh or lightly weathered oil, (2) more heavily weathered oils would require the use of an emulsion-breaking type igniter, and (3) aerial deployment of igniters offer the advantage of allowing more accurate positioning. 10 refs.,5 tabs., 3 figs

  12. Target designs for energetics experiments on the National Ignition Facility

    International Nuclear Information System (INIS)

    Meezan, N B; Glenzer, S H; Suter, L J

    2008-01-01

    The goal of the first hohlraum energetics experiments on the National Ignition Facility (NIF) [G. H. Miller et al, Optical Eng. 43, 2841 (2004)] is to select the hohlraum design for the first ignition experiments. Sub-scale hohlraums heated by 96 of the 192 laser beams on the NIF are used to emulate the laser-plasma interaction behavior of ignition hohlraums. These 'plasma emulator' targets are 70% scale versions of the 1.05 MJ, 300 eV ignition hohlraum and have the same energy-density as the full-scale ignition designs. Radiation-hydrodynamics simulations show that the sub-scale target is a good emulator of plasma conditions inside the ignition hohlraum, reproducing density n e within 10% and temperature T e within 15% along a laser beam path. Linear backscatter gain analysis shows the backscatter risk to be comparable to that of the ignition target. A successful energetics campaign will allow the National Ignition Campaign to focus its efforts on optimizing ignition hohlraums with efficient laser coupling

  13. Elements of a method to scale ignition reactor Tokamak

    International Nuclear Information System (INIS)

    Cotsaftis, M.

    1984-08-01

    Due to unavoidable uncertainties from present scaling laws when projected to thermonuclear regime, a method is proposed to minimize these uncertainties in order to figure out the main parameters of ignited tokamak. The method mainly consists in searching, if any, a domain in adapted parameters space which allows Ignition, but is the least sensitive to possible change in scaling laws. In other words, Ignition domain is researched which is the intersection of all possible Ignition domains corresponding to all possible scaling laws produced by all possible transports

  14. Ignition of an overheated, underdense, fusioning tokamak plasma

    International Nuclear Information System (INIS)

    Singer, C.E.; Jassby, D.L.; Hovey, J.

    1979-08-01

    Methods of igniting an overheated but underdense D-T plasma core with a cold plasma blanket are investigated using a simple two-zone model with a variety of transport scaling laws, and also using a one-dimensional transport code. The power consumption of neutral-beam injectors required to produce ignition can be reduced significantly if the underdense core plasma is heated to temperatures much higher than the final equilibrium ignition values, followed by fueling from a cold plasma blanket. It is also found that the allowed impurity concentration in the initial hot core can be greater than normally permitted for ignition provided that the blanket is free from impurities

  15. Take Charge. Take the Test. PSA (:30)

    Centers for Disease Control (CDC) Podcasts

    2012-03-07

    As part of the Take Charge. Take the Test. campaign, this 30 second PSA encourages African American women to get tested for HIV. Locations for a free HIV test can be found by visiting hivtest.org/takecharge or calling 1-800-CDC-INFO (1-800-232-4636).  Created: 3/7/2012 by National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention (NCHHSTP).   Date Released: 3/7/2012.

  16. Numerical Analysis of the Interaction between Thermo-Fluid Dynamics and Auto-Ignition Reaction in Spark Ignition Engines

    Science.gov (United States)

    Saijyo, Katsuya; Nishiwaki, Kazuie; Yoshihara, Yoshinobu

    The CFD simulations were performed integrating the low-temperature oxidation reaction. Analyses were made with respect to the first auto-ignition location in the case of a premixed-charge compression auto-ignition in a laminar flow field and in the case of the auto-ignition in an end gas during an S. I. Engine combustion process. In the latter simulation, the spatially-filtered transport equations were solved to express fluctuating temperatures in a turbulent flow in consideration of strong non-linearity to temperature in the reaction equations. It is suggested that the first auto-ignition location does not always occur at higher-temperature locations and that the difference in the locations of the first auto-ignition depends on the time period during which the local end gas temperature passes through the region of shorter ignition delay, including the NTC region.

  17. The value of place

    Science.gov (United States)

    Dentzau, Michael W.

    2014-03-01

    This commentary seeks to expand the dialogue on place-based science education presented in Katie Lynn Brkich's article, where the connections fifth grade students make between their formal earth science curriculum and their lived experiences are highlighted. The disconnect between the curriculum the students are offered and their immediate environment is clear, and we are presented with examples of how they strive to make connections between the content and what they are familiar with—namely their surroundings. "Place" is identified as a term with complex meanings and interpretations, even in the scope of place-based science education, and understanding how the term is used in any given scenario is essential to understanding the implications of place-based education. Is place used as a location, locale or a sense of place? To understand "place" is to acknowledge that for the individual, it is highly situational, cultural and personal. It is just such attributes that make place-based education appealing, and potentially powerful, pedagogically on one hand, yet complex for implementation on the other. The argument is posed that place is particularly important in the context of education about the environment, which in its simplest manifestation, connects formal science curriculum to resources that are local and tangible to students. The incorporation of place in such a framework seeks to bridge the gap between formal school science subjects and students' lived experiences, yet acknowledges the tensions that can arise between accommodating place meanings and the desire to acculturate students into the language of the scientific community. The disconnect between guiding policy frameworks and the reality of the Next Generation Science Standards is addressed opening an avenue for further discussion of the importance of socio-cultural frameworks of science learning in an ever increasing era of accountability.

  18. Experimental investigations of the minimum ignition energy and the minimum ignition temperature of inert and combustible dust cloud mixtures.

    Science.gov (United States)

    Addai, Emmanuel Kwasi; Gabel, Dieter; Krause, Ulrich

    2016-04-15

    The risks associated with dust explosions still exist in industries that either process or handle combustible dust. This explosion risk could be prevented or mitigated by applying the principle of inherent safety (moderation). This is achieved by adding an inert material to a highly combustible material in order to decrease the ignition sensitivity of the combustible dust. The presented paper deals with the experimental investigation of the influence of adding an inert dust on the minimum ignition energy and the minimum ignition temperature of the combustible/inert dust mixtures. The experimental investigation was done in two laboratory scale equipment: the Hartmann apparatus and the Godbert-Greenwald furnace for the minimum ignition energy and the minimum ignition temperature test respectively. This was achieved by mixing various amounts of three inert materials (magnesium oxide, ammonium sulphate and sand) and six combustible dusts (brown coal, lycopodium, toner, niacin, corn starch and high density polyethylene). Generally, increasing the inert materials concentration increases the minimum ignition energy as well as the minimum ignition temperatures until a threshold is reached where no ignition was obtained. The permissible range for the inert mixture to minimize the ignition risk lies between 60 to 80%. Copyright © 2016 Elsevier B.V. All rights reserved.

  19. Computational characterization of ignition regimes in a syngas/air mixture with temperature fluctuations

    KAUST Repository

    Pal, Pinaki; Valorani, Mauro; Arias, Paul G.; Im, Hong G.; Wooldridge, Margaret S.; Ciottoli, Pietro P.; Galassi, Riccardo M.

    2016-01-01

    ) was applied to characterize the auto-ignition phenomena. All results supported that the observed ignition behaviors were consistent with the expected ignition regimes predicted by the theory of the regime diagram. This work provides new high-fidelity data

  20. A trial of ignition innovation of gasoline engine by nanosecond pulsed low temperature plasma ignition

    International Nuclear Information System (INIS)

    Shiraishi, Taisuke; Urushihara, Tomonori; Gundersen, Martin

    2009-01-01

    Application of nanosecond pulsed low temperature plasma as an ignition technique for automotive gasoline engines, which require a discharge under conditions of high back pressure, has been studied experimentally using a single-cylinder engine. The nanosecond pulsed plasma refers to the transient (non-equilibrated) phase of a plasma before the formation of an arc discharge; it was obtained by applying a high voltage with a nanosecond pulse (FWHM of approximately 80 or 25 ns) between coaxial cylindrical electrodes. It was confirmed that nanosecond pulsed plasma can form a volumetric multi-channel streamer discharge at an energy consumption of 60 mJ cycle -1 under a high back pressure of 1400 kPa. It was found that the initial combustion period was shortened compared with the conventional spark ignition. The initial flame visualization suggested that the nanosecond pulsed plasma ignition results in the formation of a spatially dispersed initial flame kernel at a position of high electric field strength around the central electrode. It was observed that the electric field strength in the air gap between the coaxial cylindrical electrodes was increased further by applying a shorter pulse. It was also clarified that the shorter pulse improved ignitability even further.

  1. A trial of ignition innovation of gasoline engine by nanosecond pulsed low temperature plasma ignition

    Science.gov (United States)

    Shiraishi, Taisuke; Urushihara, Tomonori; Gundersen, Martin

    2009-07-01

    Application of nanosecond pulsed low temperature plasma as an ignition technique for automotive gasoline engines, which require a discharge under conditions of high back pressure, has been studied experimentally using a single-cylinder engine. The nanosecond pulsed plasma refers to the transient (non-equilibrated) phase of a plasma before the formation of an arc discharge; it was obtained by applying a high voltage with a nanosecond pulse (FWHM of approximately 80 or 25 ns) between coaxial cylindrical electrodes. It was confirmed that nanosecond pulsed plasma can form a volumetric multi-channel streamer discharge at an energy consumption of 60 mJ cycle-1 under a high back pressure of 1400 kPa. It was found that the initial combustion period was shortened compared with the conventional spark ignition. The initial flame visualization suggested that the nanosecond pulsed plasma ignition results in the formation of a spatially dispersed initial flame kernel at a position of high electric field strength around the central electrode. It was observed that the electric field strength in the air gap between the coaxial cylindrical electrodes was increased further by applying a shorter pulse. It was also clarified that the shorter pulse improved ignitability even further.

  2. Biomass ignition in mills and storages – is it explained by conventional thermal ignition theory?

    DEFF Research Database (Denmark)

    Schwarzer, Lars; Jensen, Peter Arendt; Glarborg, Peter

    of the process, which can then be incorporated into refined models of self-ignition for biomass and other organic solids. In the present study, the slow, transient heating of several lignocellulosic biomasses and a bituminous coal from ambient temperature to around 300° C were investigated in a lab scale tube...

  3. Development of a simulation model for compression ignition engine running with ignition improved blend

    Directory of Open Access Journals (Sweden)

    Sudeshkumar Ponnusamy Moranahalli

    2011-01-01

    Full Text Available Department of Automobile Engineering, Anna University, Chennai, India. The present work describes the thermodynamic and heat transfer models used in a computer program which simulates the diesel fuel and ignition improver blend to predict the combustion and emission characteristics of a direct injection compression ignition engine fuelled with ignition improver blend using classical two zone approach. One zone consists of pure air called non burning zone and other zone consist of fuel and combustion products called burning zone. First law of thermodynamics and state equations are applied in each of the two zones to yield cylinder temperatures and cylinder pressure histories. Using the two zone combustion model the combustion parameters and the chemical equilibrium composition were determined. To validate the model an experimental investigation has been conducted on a single cylinder direct injection diesel engine fuelled with 12% by volume of 2- ethoxy ethanol blend with diesel fuel. Addition of ignition improver blend to diesel fuel decreases the exhaust smoke and increases the thermal efficiency for the power outputs. It was observed that there is a good agreement between simulated and experimental results and the proposed model requires low computational time for a complete run.

  4. Development of fast ignition integrated interconnecting code (FI3) for fast ignition scheme

    International Nuclear Information System (INIS)

    Nagatomo, H.; Johzaki, T.; Mima, K.; Sunahara, A.; Nishihara, K.; Izawa, Y.; Sakagami, H.; Nakao, Y.; Yokota, T.; Taguchi, T.

    2005-01-01

    The numerical simulation plays an important role in estimating the feasibility and performance of the fast ignition. There are two key issues in numerical analysis for the fast ignition. One is the controlling the implosion dynamics to form a high density core plasma in non-spherical implosion, and the other is heating core plasma efficiency by the short pulse high intense laser. From initial laser irradiation to final fusion burning, all the physics are coupling strongly in any phase, and they must be solved consistently in computational simulation. However, in general, it is impossible to simulate laser plasma interaction and radiation hydrodynamics in a single computational code, without any numerical dissipation, special assumption or conditional treatment. Recently, we have developed 'Fast Ignition Integrated Interconnecting code' (FI 3 ) which consists of collective Particle-in-Cell code, Relativistic Fokker-Planck hydro code, and 2-dimensional radiation hydrodynamics code. And those codes are connecting with each other in data-flow bases. In this paper, we will present detail feature of the FI 3 code, and numerical results of whole process of fast ignition. (author)

  5. Influence of several factors on ignition lag in a compression-ignition engine

    Science.gov (United States)

    Gerrish, Harold C; Voss, Fred

    1932-01-01

    This investigation was made to determine the influence of fuel quality, injection advance angle, injection valve-opening pressure, inlet-air pressure, compression ratio, and engine speed on the time lag of auto-ignition of a Diesel fuel oil in a single-cylinder compression-ignition engine as obtained from an analysis of indicator diagrams. Three cam-operated fuel-injection pumps, two pumps cams, and an automatic injection valve with two different nozzles were used. Ignition lag was considered to be the interval between the start of injection of the fuel as determined with a Stroborama and the start of effective combustion as determined from the indicator diagram, the latter being the point where 4.0 x 10(exp-6) pound of fuel had been effectively burned. For this particular engine and fuel it was found that: (1) for a constant start and the same rate of fuel injection up the point of cut-off, a variation in fuel quantity from 1.2 x 10(exp-4) to 4.1 x 10(exp-4) pound per cycle has no appreciable effect on the ignition lag; (2) injection advance angle increases or decreases the lag according to whether density, temperature, or turbulence has the controlling influence; (3) increase in valve-opening pressure slightly increases the lag; and (4) increase of inlet-air pressure, compression ratio, and engine speed reduces the lag.

  6. Technical training: places available

    CERN Multimedia

    HR Department

    2007-01-01

    CERN Technical Training: Open Courses (April - June 2007) The following course sessions are currently scheduled in the framework of the CERN Technical Training Programme 2007:   AutoCAD 2006 - niveau 1 (course in French): 25.4.- 26.4.2007 & 2.5. - 3.5.2007 (4 days in 2 modules, 5 places available) AutoCAD 2006 - niveau 1 (course in French): 27.6.- 28.6.2007 & 3.7. - 4.7.2007 (4 days in 2 modules, 5 places available) AutoCAD Mechanical 2006 (course in French) 21.6.-22.6.2007 (2 days, 8 places available) * NEW COURSE* Automate de securite S7 (course in French) 14.5.-16.5.2007 (3 days, 4 places available) * NEW COURSE* Automate de securite S7 (course in French): 9.5.-11.5.2007 (3 days, 4 places available) JCOP - Joint PVSS-JCOP Frameswork (course in English): 21.5.-25.5.2007 (5 days, 12 places available) JCOP - Finite State Machines in the JCOP Frameswork (course in English): 12.6.-14.6.2007 (3 days, 12 places available) LabVIEW Basics 1 (in English): 2.-4.5.2007 (3 days, 7 places ...

  7. A Sense of Place

    Directory of Open Access Journals (Sweden)

    Rachel Black

    2012-09-01

    Full Text Available People increasingly want to know where their food and wine comes from and who produces it. This is part of developing a taste of place, or what the French call terroir. The academic and industry debates surrounding the concept of terroir are explored, and the efforts of Massachusetts wine producers to define their sense of place are discussed.

  8. Place in transition

    DEFF Research Database (Denmark)

    Mikkelsen, Jacob Bjerre; Lange, Ida Sofie Gøtzsche

    2017-01-01

    World. This paper discusses the conception of place in the Oil World, with the relocation and transformation of oil rigs from an urban design perspective as its point of departure, using Esbjerg, Denmark, as a case study. Combining a theoretical understanding of places as relational with a design...

  9. The Case for Place

    Science.gov (United States)

    Thomas, Lisa Carlucci

    2012-01-01

    Bookstores, record stores, libraries, Facebook: these places--both physical and virtual--demonstrate an established and essential purpose as centers of community, expertise, convenience, immediacy, and respect. Yet as digital, mobile, and social shifts continue to transform culture and interactions, these spaces and places transform, too.…

  10. Non-Place

    DEFF Research Database (Denmark)

    formulation. The anthology contains 17 articles engaged directly in the application, retrofitting and broadening of the concept of the non-place to a range of literary and media texts, as well as the merging of this concept to other theoretical concepts by e.g. Michel Foucault, Gilles Deleuze, Alain Badiou......We spend more and more of our everyday lives in what Marc Augé calls non-places – homogenous, but bland places of transit. This anthology addresses the representations of non-places in literature, culture and media, and critiques and re-actualizes Augé’s work twenty years after its initial...... Jutland, and many others. This anthology is the seventh publication in the IRGiC series and it springs from a research seminar held at Aalborg University in May 2013: “Non-Place in Literature, Media and Culture”....

  11. Place-Specific Computing

    DEFF Research Database (Denmark)

    Messeter, Jörn; Johansson, Michael

    project place- specific computing is explored through design oriented research. This article reports six pilot studies where design students have designed concepts for place-specific computing in Berlin (Germany), Cape Town (South Africa), Rome (Italy) and Malmö (Sweden). Background and arguments...... for place-specific computing as a genre of interaction design are described. A total number of 36 design concepts designed for 16 designated zones in the four cities are presented. An analysis of the design concepts is presented indicating potentials, possibilities and problems as directions for future......An increased interest in the notion of place has evolved in interaction design. Proliferation of wireless infrastructure, developments in digital media, and a ‘spatial turn’ in computing provides the base for place-specific computing as a suggested new genre of interaction design. In the REcult...

  12. Technical training - places available

    CERN Multimedia

    2012-01-01

    If you would like more information on a course, or for any other inquiry/suggestions, please contact Technical.Training@cern.ch Valeria Perez Reale, Learning Specialist, Technical Programme Coordinator (Tel.: 62424) Eva Stern and Elise Romero, Technical Training Administration (Tel.: 74924) HR Department »Electronics design Next Session Duration Language Availability Comprehensive VHDL for FPGA Design 08-Oct-12 to 12-Oct-12 5 days English 3 places available Foundations of Electromagnetism and Magnet Design (EMAG) 14-Nov-12 to 27-Nov-12 6 days English 20 places available Impacts de la suppression du plomb (RoHS) en électronique 26-Oct-12 to 26-Oct-12 8 hours French 15 places available Introduction to VHDL 10-Oct-12 to 11-Oct-12 2 days English 7 places available LabVIEW Real Time and FPGA 13-Nov-12 to 16-Nov-12 5 days French 5 places available »Mechanical design Next Se...

  13. 'Crescent'-shaped tokamak for compact ignition

    International Nuclear Information System (INIS)

    Yamazaki, K.; Reiersen, W.T.

    1985-12-01

    A compact high-beta tokamak configuration with ''crescent''-shaped (or ''boomerang''-shaped) cross-section is proposed as a next-generation ignition machine. This configuration with a small indentation but a large triangularity is more compact than the normal dee-shaped design because of its high-beta characteristics in the first-second transition regime of stability. This may also be a more reliable next-generation compact device than the bean-shaped design with large indentation and small triangularity, because this design dose not rely on the second stability and is easily extendable from the present dee-shaped design. (author)

  14. 'Crescent'-shaped tokamak for compact ignition

    International Nuclear Information System (INIS)

    Yamazaki, K.; Reiersen, W.T.

    1986-01-01

    A compact high-beta tokamak configuration with ''crescent''-shaped (or ''boomerang''-shaped) cross section is proposed as a next-generation ignition machine. This configuration with a small indentation but a large triangularity is more compact than the normal dee-shaped design because of its high-beta characteristics in the first-second transition regime of stability. This may also be a more reliable next-generation compact device than the bean-shaped design with large indentation and small triangularity, because this design does not rely on the second stability and is easily extendable from the present dee-shaped design. (author)

  15. Fast ignition studies at Osaka University

    International Nuclear Information System (INIS)

    Tanaka, K. A.

    2007-01-01

    After the invention of the chirped pulse amplification technique [1], the extreme conditions of matters have become available in laboratory spaces and can be studied with the use of ultra intense laser pulse (UILP) with a high energy. One such example is the fast ignition [2] where UILP is used to heat a highly compressed fusion fuel core within 1-10 pico-seconds before the core disassembles. It is predicted possible with use of 50-100 kJ lasers for both imploding the fuel and heating [2] to attain a large fusion gain. Fast ignition was shown to be a promising new scheme for laser fusion [3] with a PW (= 10 1 5 W) UILP and GEKKO XII laser systems at Osaka. Many new physics have been found with use of UILP in a relativistic parameter regime during the process of the fast ignition studies. UILP can penetrate into over-dense plasma for a couple hundred microns distance with a self-focusing and relativistic transparency effects. Hot electrons of 1-100 MeV can be easily created and are under studies for its spectral and emission angle controls. Strong magnetic fields of 10's of MGauss are created to guide these hot electrons along the target surface [4]. Based on these results, a new and largest UILP laser machine of 10 kJ energy at PW UILP peak power is under construction to test if we can achieve the sub-ignition fusion condition at Osaka University. The machine requires challenging optical technologies such as large size (0.9 m) gratings, tiling these gratings for UILP compression; segmenting four large UILP beams to obtain diffraction limited focal spot. We would like to over-view all of these activities. References [1]D. STRICKLAND and G. MOUROU, Opt. Commun., 56, 219 (1985) [2] S. ATZENI et al., Phys Plasmas, 6, 3316 (1999) [3] R. KODAMA, K.A. TANAKA et al., Nature, 418, 933 (2002) [4] A.L. LEI, K.A. TANAKA et al., Phys. Rev. Lett., 96, 255006(2006) ; H. HABARA, K.A. TANAKA et al., Phys. Rev. Lett., 97, 095004 (2006)

  16. Neutral beam system for an ignition tokamak

    International Nuclear Information System (INIS)

    Fasolo, J.; Fuja, R.; Jung, J.; Moenich, J.; Norem, J.; Praeg, W.; Stevens, H.

    1978-01-01

    We have attempted to make detailed designs of several neutral beam systems which would be applicable to a large machine, e.g. an ITR (Ignition Test Reactor), EPR (Experimental Power Reactor), or reactor. Detailed studies of beam transport to the reactor and neutron transport from the reactor have been made. We have also considered constraints imposed by the neutron radiation environment in the injectors, and the resulting shielding, radiation-damage, and maintenance problems. The effects of neutron heat loads on cryopanels and ZrAl getter panels have been considered. Design studies of power supplies, vacuum systems, bending magnets, and injector layouts are in progress and will be discussed

  17. Uncertainties associated with inertial-fusion ignition

    International Nuclear Information System (INIS)

    McCall, G.H.

    1981-01-01

    An estimate is made of a worst case driving energy which is derived from analytic and computer calculations. It will be shown that the uncertainty can be reduced by a factor of 10 to 100 if certain physical effects are understood. That is not to say that the energy requirement can necessarily be reduced below that of the worst case, but it is possible to reduce the uncertainty associated with ignition energy. With laser costs in the $0.5 to 1 billion per MJ range, it can be seen that such an exercise is worthwhile

  18. Effects of electrode geometry on transient plasma induced ignition

    International Nuclear Information System (INIS)

    Shukla, B; Gururajan, V; Eisazadeh-Far, K; Windom, B; Egolfopoulos, F N; Singleton, D; Gundersen, M A

    2013-01-01

    Achieving effective ignition of reacting mixtures using nanosecond pulsed discharge non-equilibrium transient plasma (TP), requires that the effects of several experimental parameters be quantified and understood. Among them are the electrode geometry, the discharge location especially in non-premixed systems, and the relative ignition performance by spark and TP under the same experimental conditions. In the present investigation, such issues were addressed experimentally using a cylindrical constant volume combustion chamber and a counterflow flame configuration coupled with optical shadowgraph that enables observation of how and where the ignition process starts. Results were obtained under atmospheric pressure and showed that the electrode geometry has a notable influence on ignition, with the needle-to-semicircle exhibiting the best ignition performance. Furthermore, it was determined that under non-premixed conditions discharging TP in the reactants mixing layer was most effective in achieving ignition. It was also determined that in the cases considered, the TP induced ignition initiates from the needle head where the electric field and electron densities are the highest. In the case of a spark, however, ignition was found to initiate always from the hot region between the two electrodes. Comparison of spark and TP discharges in only air (i.e. without fuel) and ignition phenomena induced by them also suggest that in the case of TP ignition is at least partly non-thermal and instead driven by the production of active species. Finally, it was determined that single pulsed TP discharges are sufficient to ignite both premixed and non-premixed flames of a variety of fuels ranging from hydrogen to heavy fuels including F-76 diesel and IFO380 bunker fuel even at room temperature. (paper)

  19. Laser driven inertial fusion: the physical basis of current and recently proposed ignition experiments

    International Nuclear Information System (INIS)

    Atzeni, S

    2009-01-01

    A brief overview of the inertial fusion principles and schemes is presented. The bases for the laser driven ignition experiments programmed for the near future at the National Ignition Facility are outlined. These experiments adopt indirect-drive and aim at central ignition. The principles of alternate approaches, based on direct-drive and different routes to ignition (fast ignition and shock ignition) are also discussed. Gain curves are compared and discussed.

  20. Where is 'place' in Aging in place?

    DEFF Research Database (Denmark)

    Blaakilde, Anne Leonora

    2015-01-01

    is influenced by universalism, aiming at equality in terms of access to health services and care. However, these welfare provisions seem to be deeply embedded in methodological nationalism, since only citizens with residence within the borders of Denmark have the right to live in public nursing homes or receive......The aim of this article is to contribute a transnational perspective to the field of environmental gerontology and the concept of aging in place. Seniors from the northern hemisphere, among them Danish citizens, are increasingly adapting to transnational lives as they move to warmer climates...... in-home help. It is argued that we should consider public solutions to the problems faced by frail Danish citizens in transnational settings, enhancing their opportunities to live abroad....

  1. Early-time radiation flux symmetry optimization and its effect on gas-filled hohlraum ignition targets on the National Ignition Facility

    Energy Technology Data Exchange (ETDEWEB)

    Milovich, J. L., E-mail: milovich1@llnl.gov; Dewald, E. L.; Pak, A.; Michel, P.; Town, R. P. J.; Bradley, D. K.; Landen, O.; Edwards, M. J. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)

    2016-03-15

    Achieving ignition on the National Ignition Facility (NIF) is tied to our ability to control and minimize deviations from sphericity of the capsule implosion. Low-mode asymmetries of the hot spot result from the combined effect of radiation drive asymmetries throughout the laser pulse and initial roughness on the capsule surface. In this paper, we report on simulations and experiments designed to assess, measure, and correct the drive asymmetries produced by the early-time (≈first 2 ns or “picket”) period of the laser pulse. The drive asymmetry during the picket is commonly thought to introduce distortions in the hot-spot shape at ignition time. However, a more subtle effect not previously considered is that it also leads to an asymmetry in shock velocity and timing, thereby increasing the fuel adiabat and reducing the margin for ignition. It is shown via hydrodynamic simulations that minimizing this effect requires that the early-time asymmetry be kept below 7.5% in the second Legendre mode (P{sub 2}), thus keeping the loss of performance margin below ≈10% for a layered implosion. Asymmetries during the picket of the laser pulse are measured using the instantaneous self-emission of a high-Z re-emission sphere in place of an ignition capsule in a hohlraum with large azimuthal diagnostic windows. Three dimensional simulations using the code HYDRA (to capture the effect of non-azimuthal hohlraum features) coupled to a cross-beam energy transfer model [Michel et al., Phys. Plasmas 17, 056305 (2010)] are used to establish the surrogacy of the re-emit target and to assess the early-time drive symmetry. Calculations using this model exhibit the same sensitivity to variations in the relative input powers between the different cones of NIF beams as measured for the “Rev5” CH target [Haan et al., Phys Plasmas 18, 051001 (2011)] and reported by Dewald et al. [Phys. Rev. Lett. 111, 235001 (2013)]. The same methodology applied to recently improved implosions

  2. Early-time radiation flux symmetry optimization and its effect on gas-filled hohlraum ignition targets on the National Ignition Facility

    International Nuclear Information System (INIS)

    Milovich, J. L.; Dewald, E. L.; Pak, A.; Michel, P.; Town, R. P. J.; Bradley, D. K.; Landen, O.; Edwards, M. J.

    2016-01-01

    Achieving ignition on the National Ignition Facility (NIF) is tied to our ability to control and minimize deviations from sphericity of the capsule implosion. Low-mode asymmetries of the hot spot result from the combined effect of radiation drive asymmetries throughout the laser pulse and initial roughness on the capsule surface. In this paper, we report on simulations and experiments designed to assess, measure, and correct the drive asymmetries produced by the early-time (≈first 2 ns or “picket”) period of the laser pulse. The drive asymmetry during the picket is commonly thought to introduce distortions in the hot-spot shape at ignition time. However, a more subtle effect not previously considered is that it also leads to an asymmetry in shock velocity and timing, thereby increasing the fuel adiabat and reducing the margin for ignition. It is shown via hydrodynamic simulations that minimizing this effect requires that the early-time asymmetry be kept below 7.5% in the second Legendre mode (P_2), thus keeping the loss of performance margin below ≈10% for a layered implosion. Asymmetries during the picket of the laser pulse are measured using the instantaneous self-emission of a high-Z re-emission sphere in place of an ignition capsule in a hohlraum with large azimuthal diagnostic windows. Three dimensional simulations using the code HYDRA (to capture the effect of non-azimuthal hohlraum features) coupled to a cross-beam energy transfer model [Michel et al., Phys. Plasmas 17, 056305 (2010)] are used to establish the surrogacy of the re-emit target and to assess the early-time drive symmetry. Calculations using this model exhibit the same sensitivity to variations in the relative input powers between the different cones of NIF beams as measured for the “Rev5” CH target [Haan et al., Phys Plasmas 18, 051001 (2011)] and reported by Dewald et al. [Phys. Rev. Lett. 111, 235001 (2013)]. The same methodology applied to recently improved implosions using

  3. Early-time radiation flux symmetry optimization and its effect on gas-filled hohlraum ignition targets on the National Ignition Facility

    Science.gov (United States)

    Milovich, J. L.; Dewald, E. L.; Pak, A.; Michel, P.; Town, R. P. J.; Bradley, D. K.; Landen, O.; Edwards, M. J.

    2016-03-01

    Achieving ignition on the National Ignition Facility (NIF) is tied to our ability to control and minimize deviations from sphericity of the capsule implosion. Low-mode asymmetries of the hot spot result from the combined effect of radiation drive asymmetries throughout the laser pulse and initial roughness on the capsule surface. In this paper, we report on simulations and experiments designed to assess, measure, and correct the drive asymmetries produced by the early-time (≈first 2 ns or "picket") period of the laser pulse. The drive asymmetry during the picket is commonly thought to introduce distortions in the hot-spot shape at ignition time. However, a more subtle effect not previously considered is that it also leads to an asymmetry in shock velocity and timing, thereby increasing the fuel adiabat and reducing the margin for ignition. It is shown via hydrodynamic simulations that minimizing this effect requires that the early-time asymmetry be kept below 7.5% in the second Legendre mode (P2), thus keeping the loss of performance margin below ≈10% for a layered implosion. Asymmetries during the picket of the laser pulse are measured using the instantaneous self-emission of a high-Z re-emission sphere in place of an ignition capsule in a hohlraum with large azimuthal diagnostic windows. Three dimensional simulations using the code HYDRA (to capture the effect of non-azimuthal hohlraum features) coupled to a cross-beam energy transfer model [Michel et al., Phys. Plasmas 17, 056305 (2010)] are used to establish the surrogacy of the re-emit target and to assess the early-time drive symmetry. Calculations using this model exhibit the same sensitivity to variations in the relative input powers between the different cones of NIF beams as measured for the "Rev5" CH target [Haan et al., Phys Plasmas 18, 051001 (2011)] and reported by Dewald et al. [Phys. Rev. Lett. 111, 235001 (2013)]. The same methodology applied to recently improved implosions using different

  4. Taking iron supplements

    Science.gov (United States)

    ... medlineplus.gov/ency/article/007478.htm Taking iron supplements To use the sharing features on this page, ... levels. You may also need to take iron supplements as well to rebuild iron stores in your ...

  5. Context in place

    DEFF Research Database (Denmark)

    Nordentoft, Helle Merete; Thomsen, Rie

    specifically argue for a more grounded approach to the conception of context - a topographic approach - in which the physical setting - i.e. 'the place' becomes an inevitable part of analyses of guidance practices in order to understand participants' sense-making processes. In the paper we draw on two case...... studies on interdisciplinary clinical supervision and work place guidance in which there appears to be a mismatch between intended outcomes and actual events. The analyses demonstrate and support that 'the place' seems - to influence partipants' responses in the guidance sessions and, therefore, must...

  6. Ignition delay time correlation of fuel blends based on Livengood-Wu description

    KAUST Repository

    Khaled, Fathi; Badra, Jihad; Farooq, Aamir

    2017-01-01

    observed for combustion phasing in homogeneous charge compression ignition (HCCI) predictions between simulations performed with detailed chemistry and calculations using the developed ignition delay correlation.

  7. Management and communication courses – Places available

    CERN Multimedia

    2013-01-01

    There are places available in some management and communication courses taking place in the period April to June 2013.   For more information on the course, click on the course title, this will bring you to the training catalogue. You can then sign-up online. For advice, you can contact: - Erwin Mosselmans, tel. 74125, erwin.mosselmans@cern.ch - Nathalie Dumeaux, tel. 78144, nathalie.dumeaux@cern.ch Courses in English (or bilingual) Sessions Duration Language Availability Managing stress 29 and 30 May 2 days English 3 places Making Presentations 30, 31 May & 25 June 3 days English 2 places Communicating Effectively - Residential course 4 to 6 June 3 days Bilingual 9 places Handling difficult conversations (Adapted from Dealing with Conflict) 7 and 14 June and 13 September 3 days English 6 places Voice and Nonverbal Behaviour in Speech Communication 17 and 18 June 1 day 4 hours English 7 plac...

  8. Recent progress on the Compact Ignition Tokamak (CIT)

    International Nuclear Information System (INIS)

    Ignat, D.W.

    1987-01-01

    This report describes work done on the Compact Ignition Tokamak (CIT), both at the Princeton Plasma Physics Laboratory (PPPL) and at other fusion laboratories in the United States. The goal of CIT is to reach ignition in a tokamak fusion device in the mid-1990's. Scientific and engineering features of the design are described, as well as projected cost and schedule

  9. Ignition and burn propagation with suprathermal electron auxiliary heating

    International Nuclear Information System (INIS)

    Han Shensheng; Wu Yanqing

    2000-01-01

    The rapid development in ultrahigh-intensity lasers has allowed the exploration of applying an auxiliary heating technique in inertial confinement fusion (ICF) research. It is hoped that, compared with the 'standard fast ignition' scheme, raising the temperature of a hot-spot over the ignition threshold based on the shock-heated temperature will greatly reduce the required output energy of an ignition ultrahigh-intensity pulse. One of the key issues in ICF auxiliary heating is: how can we transport the exogenous energy efficiently into the hot-spot of compressed DT fuel? A scheme is proposed with three phases. First, a partial-spherical-shell capsule, such as double-conical target, is imploded as in the conventional approach to inertial fusion to assemble a high-density fuel configuration with a hot-spot of temperature lower than the ignition threshold. Second, a hole is bored through the shell outside the hot-spot by suprathermal electron explosion boring. Finally, the fuel is ignited by suprathermal electrons produced in the high-intensity ignition laser-plasma interactions. Calculations with a simple hybrid model show that the new scheme can possibly lead to ignition and burn propagation with a total drive energy of a few tens of kilojoules and an output energy as low as hundreds of joules for a single ignition ultrahigh-intensity pulse. (author)

  10. Evaluation of the ignition behaviour of coals and blends

    Energy Technology Data Exchange (ETDEWEB)

    J. Faundez; F. Rubiera; X. Garcia; A. Arenillas; A.L. Gordon; J.J. Pis [CSIC, Instituto Nacional del Carbon, Oviedo (Spain). Department of Energy and Environment

    2003-07-01

    An experimental study about ignition of coals and blends was carried out by using an entrained flow reactor (EFR) with continuous feed. Seven coals of varying rank, from subbituminous to semianthracite, were tested and evolving gases (O{sub 2}, CO, CO{sub 2}, NO) were measured. The ignition temperature was evaluated from the evolution profiles of these gases, and correlated inversely to the reactivity of coals, as reflected by increasing values of ignition temperatures in the sequence subbituminous, high volatile bituminous, low volatile bituminous and semianthracite coals. Mechanism of ignition varied from an heterogeneous mechanism (for subbituminous, low volatile bituminous and semianthracite coals) to an homogeneous mechanism (for high volatile bituminous coal). Experiments with coal blends showed that if a low volatile bituminous coal is blended with a high volatile bituminous coal, the latter determines the value of the ignition temperature and ignition mechanism of the blend, when its percentage in the blend is 50% or higher. For blends of subbituminous and high volatile bituminous coals, the ignition mechanism of the blend is determined by the ignition mechanism of the coal with a higher content in the blend. 12 refs., 9 figs., 1 tab.

  11. Dynamic ignition regime of condensed system by radiate heat flux

    International Nuclear Information System (INIS)

    Arkhipov, V A; Zolotorev, N N; Korotkikh, A G; Kuznetsov, V T

    2017-01-01

    The main ignition characteristics of high-energy materials are the ignition time and critical heat flux allowing evaluation of the critical conditions for ignition, fire and explosive safety for the test solid propellants. The ignition process is typically studied in stationary conditions of heat input at constant temperature of the heating surface, environment or the radiate heat flux on the sample surface. In real conditions, ignition is usually effected at variable time-dependent values of the heat flux. In this case, the heated layer is formed on the sample surface in dynamic conditions and significantly depends on the heat flux change, i.e. increasing or decreasing falling heat flux in the reaction period of the propellant sample. This paper presents a method for measuring the ignition characteristics of a high-energy material sample in initiation of the dynamic radiant heat flux, which includes the measurement of the ignition time when exposed to a sample time varying radiant heat flux given intensity. In case of pyroxyline containing 1 wt. % of soot, it is shown that the ignition times are reduced by 20–50 % depending on the initial value of the radiant flux density in initiation by increasing or decreasing radiant heat flux compared with the stationary conditions of heat supply in the same ambient conditions. (paper)

  12. Shock Timing Plan for the National Ignition Campaign

    Science.gov (United States)

    Munro, D. H.; Robey, H. F.; Spears, B. K.; Boehly, T. R.

    2006-10-01

    We report progress on the design of the shock timing tuning procedure for the 2010 ignition campaign at the National Ignition Facility. Our keyhole target design provides adequate drive surrogacy for us to time the first three shocks empirically. The major risk to our plan is hard x-ray preheat, which can cause the diagnostic window to become opaque.

  13. Hot-wire ignition of AN-based emulsions

    Energy Technology Data Exchange (ETDEWEB)

    Turcotte, Richard; Goldthorp, Sandra; Badeen, Christopher M. [Canadian Explosives Research Laboratory, Natural Resources Canada, Ottawa, Ontario, K1A 0G1 (Canada); Chan, Sek Kwan [Orica Canada Inc., Brownsburg-Chatham, Quebec (Canada)

    2008-12-15

    Emulsions based on ammonium nitrate (AN) and water locally ignited by a heat source do not undergo sustained combustion when the pressure is lower than some threshold value usually called the Minimum Burning Pressure (MBP). This concept is now being used by some manufacturers as a basis of safety. However, before a technique to reliably measure MBP values can be designed, one must have a better understanding of the ignition mechanism. Clearly, this is required to avoid under ignitions which could lead to the erroneous interpretation of failures to ignite as failures to propagate. In the present work, facilities to prepare and characterize emulsions were implemented at the Canadian Explosives Research Laboratory. A calibrated hot-wire ignition system operated in a high-pressure vessel was also built. The system was used to study the ignition characteristics of five emulsion formulations as a function of pressure and ignition source current. It was found that these mixtures exhibit complicated pre-ignition stages and that the appearance of endotherms when the pressure is lowered below some threshold value correlates with the MBP. Thermal conductivity measurements using this hot-wire system are also reported. (Abstract Copyright [2008], Wiley Periodicals, Inc.)

  14. Influence of anomalous thermal losses of ignition conditions

    International Nuclear Information System (INIS)

    Coppi, B.; Tang, W.M.

    1986-05-01

    In the process of achieving ignition conditions, it is likely that microinstabilities, which lead to anomalous thermal transport of the fusing nuclei, will be present. When such phenomena are taken into account, an appropriate formulation of ignition criteria becomes necessary. In particular, a new type of plasma density limit is identified

  15. 14 CFR 25.981 - Fuel tank ignition prevention.

    Science.gov (United States)

    2010-01-01

    ... AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Powerplant Fuel System § 25.981 Fuel tank... system where catastrophic failure could occur due to ignition of fuel or vapors. This must be shown by... established, as necessary, to prevent development of ignition sources within the fuel tank system pursuant to...

  16. Remote control flare stack igniter for combustible gases

    Science.gov (United States)

    Ray, W. L.

    1972-01-01

    Device has been designed and developed for igniting nonrecoverable combustible gases and sustaining combustion of gases evolving from various gas vent stacks. Igniter is superior to existing systems because of simplicity of operation, low cost fabrication, installation, operational and maintainability features, and excellent reliability in all phases of required operations.

  17. Report on ignitability testing of ''no-flow'' push bit

    International Nuclear Information System (INIS)

    Witwer, K.S.

    1997-01-01

    Testing was done to determine if an ignition occurs during a sixty foot drop of a Universal Sampler onto a push-mode bit in a flammable gas environment. Ten drops each of the sampler using both a push-mode and rotary mode insert onto a push-mode bit were completed. No ignition occurred during any of the drops

  18. Combustion and operating characteristics of spark-ignition engines

    Science.gov (United States)

    Heywood, J. B.; Keck, J. C.; Beretta, G. P.; Watts, P. A.

    1980-01-01

    The spark-ignition engine turbulent flame propagation process was investigated. Then, using a spark-ignition engine cycle simulation and combustion model, the impact of turbocharging and heat transfer variations or engine power, efficiency, and NO sub x emissions was examined.

  19. The mechanism of char ignition in fluidized bed combustors

    NARCIS (Netherlands)

    Siemons, R.V.

    1987-01-01

    Knowledge about ignition processes of coal in fluidized beds is of importance for the start-up and dynamic control of these combustors. Initial experiments in a transparent fluidized bed scale model showed the existence of a considerable induction period for the ignition of char, especially at low

  20. Deuterium–tritium catalytic reaction in fast ignition: Optimum ...

    Indian Academy of Sciences (India)

    proton beam, the corresponding optimum interval values are proton average energy 3 ... contributions, into the study of the ignition and burn dynamics in a fast ignition frame- ..... choice of proton beam energy would fall in 3 ≤ Ep ≤ 10 MeV.

  1. Initial assessments of ignition spherical torus

    International Nuclear Information System (INIS)

    Peng, Y.K.M.; Borowski, S.K.; Bussell, G.T.

    1985-12-01

    Initial assessments of ignition spherical tori suggest that they can be highly cost effective and exceptionally small in unit size. Assuming advanced methods of current drive to ramp up the plasma current (e.g., via lower hybrid wave at modest plasma densities and temperatures), the inductive solenoid can largely be eliminated. Given the uncertainties in plasma energy confinement times and the effects of strong paramagnetism on plasma pressure, and allowing for the possible use of high-strength copper alloys (e.g., C-17510, Cu-Ni-Be alloy), ignition spherical tori with a 50-s burn are estimated to have major radii ranging from 1.0 to 1.6 m, aspect ratios from 1.4 to 1.7, vacuum toroidal fields from 2 to 3 T, plasma currents from 10 to 19 MA, and fusion power from 50 to 300 MW. Because of its modest field strength and simple poloidal field coil configuration, only conventional engineering approaches are needed in the design. A free-standing toroidal field coil/vacuum vessel structure is assessed to be feasible and relatively independent of the shield structure and the poloidal field coils. This exceptionally simple configuration depends significantly, however, on practical fabrication approaches of the center conductor post, about which there is presently little experience. 19 refs

  2. 8. High power laser and ignition facilities

    International Nuclear Information System (INIS)

    Bayramian, A.J.; Beach, R.J.; Bibeau, C.

    2002-01-01

    This document gives a review of the various high power laser projects and ignition facilities in the world: the Mercury laser system and Electra (Usa), the krypton fluoride (KrF) laser and the HALNA (high average power laser for nuclear-fusion application) project (Japan), the Shenguang series, the Xingguang facility and the TIL (technical integration line) facility (China), the Vulcan peta-watt interaction facility (UK), the Megajoule project and its feasibility phase: the LIL (laser integration line) facility (France), the Asterix IV/PALS high power laser facility (Czech Republic), and the Phelix project (Germany). In Japan the 100 TW Petawatt Module Laser, constructed in 1997, is being upgraded to the world biggest peta-watt laser. Experiments have been performed with single-pulse large aperture e-beam-pumped Garpun (Russia) and with high-current-density El-1 KrF laser installation (Russia) to investigate Al-Be foil transmittance and stability to multiple e-beam irradiations. An article is dedicated to a comparison of debris shield impacts for 2 experiments at NIF (national ignition facility). (A.C.)

  3. Safety overview of the National Ignition Facility

    International Nuclear Information System (INIS)

    Brereton, S.J.; McLouth, L.; Odell, B.; Singh, M.; Tobin, M.; Trent, M.

    1996-01-01

    The National Ignition Facility (NIF) is a proposed US Department of Energy inertial confinement laser fusion facility. The candidate sites for locating the NIF are: Los Alamos National Laboratory, Sandia National Laboratory, the Nevada Test Site, and Lawrence Livermore National Laboratory (LLNL), the preferred site. The NIF will operate by focusing 192 laser beams onto a tiny deuterium- tritium target located at the center of a spherical target chamber. The NIF mission is to achieve inertial confinement fusion (ICF) ignition, access physical conditions in matter of interest to nuclear weapons physics, provide an above ground simulation capability for nuclear weapons effects testing, and contribute to the development of inertial fusion for electrical power production. The NIF has been classified as a radiological, low hazard facility on the basis of a preliminary hazards analysis and according to the DOE methodology for facility classification. This requires that a safety analysis be prepared under DOE Order 5481.1B, Safety Analysis and Review System. A draft Preliminary Safety Analysis Report (PSAR) has been written, and this will be finalized later in 1996. This paper summarizes the safety issues associated with the operation of the NIF. It provides an overview of the hazards, estimates maximum routine and accidental exposures for the preferred site of LLNL, and concludes that the risks from NIF operations are low

  4. System studies of compact ignition tokamaks

    International Nuclear Information System (INIS)

    Galambos, J.D.; Peng, Y.K.M.; Blackfield, D.T.

    1986-01-01

    A new version of the FEDC Tokamak System Code (TSC) has been developed to analyze the Compact Ignition Tokamak (CIT). These proposed experiments have small (major radius F 1.5m) and high magnetic fields (B J 10T), and are characterized by reduced cost. Key design constraints of CIT include limits to the high stress levels in the magnetic coils, limits to the large temperature rises in the coils and on the first wall or divertor plate, minimizing power supply requirements, and assuring adequate plasma performance in fusion ignition and burn time consistent with the latest physics understanding. We present systems code level studies of CIT parameter space here for a range of design options with various design constraints. The present version of the TSC incorporates new models for key components of CIT. For example, new algorithms have been incorporated for calculating stress levels in the TFC and ohmic solenoid, temperature rise in the magnetic coils, peak power requirements, plasma MHD equilibrium and volt-second capability. The code also incorporates a numerical optimizer to find combinations of engineering quantities (device size, coil sizes, coil current densities etc.) and physics quantities (plasma density temperature, and beta, etc.) which satisfy all the constraints and can minimize or maximize a figure of merit (e.g., the major radius). This method was recently used in a mirror reactor system code (3) for the Minimara concept development

  5. Compact Ignition Tokamak conventional facilities optimization

    International Nuclear Information System (INIS)

    Commander, J.C.; Spang, N.W.

    1987-01-01

    A high-field ignition machine with liquid-nitrogen-cooled copper coils, designated the Compact Ignition Tokamak (CIT), is proposed for the next phase of the United States magnetically confined fusion program. A team of national laboratory, university, and industrial participants completed the conceptual design for the CIT machine, support systems and conventional facilities. Following conceptual design, optimization studies were conducted with the goal of improving machine performance, support systems design, and conventional facilities configuration. This paper deals primarily with the conceptual design configuration of the CIT conventional facilities, the changes that evolved during optimization studies, and the revised changes resulting from functional and operational requirements (F and ORs). The CIT conventional facilities conceptual design is based on two premises: (1) satisfaction of the F and ORs developed in the CIT building and utilities requirements document, and (2) the assumption that the CIT project will be sited at the Princeton Plasma Physics Laboratory (PPPL) in order that maximum utilization can be made of existing Tokamak Fusion Test Reactor (TFTR) buildings and utilities. The optimization studies required reevaluation of the F and ORs and a second look at TFTR buildings and utilities. Some of the high-cost-impact optimization studies are discussed, including the evaluation criteria for a change from the conceptual design baseline configuration. The revised conventional facilities configuration are described and the estimated cost impact is summarized

  6. Progress toward ignition with direct-drive

    International Nuclear Information System (INIS)

    McCrory, R.L. Jr.

    1993-01-01

    The goal of the direct-drive laser fusion program is to validate high-performance, direct-drive targets. A decision to construct a direct-drive capability on the proposed 1-to-2-MJ National Ignition Facility (NIF) in the USA will be based on target physics experiments conducted on the OMEGA Upgrade laser system now under construction at the LLE. The OMEGA Upgrade will provide up to 30 kJ of UV laser energy in precisely shaped pulses with irradiation nonuniformities in the range of 1 pc. to 2 pc. An understanding and predictive capability for direct-drive targets are required to assure reliable estimates of ignition and gain with 1-2 MJ of incident laser energy. This paper reviews the target physics efforts currently underway to assess the critical physics issues of direct-drive ICF; plans for the experimental program to be carried out on the OMEGA Upgrade laser are also presented. 14 figs., 15 refs

  7. National Ignition Facility project acquisition plan

    International Nuclear Information System (INIS)

    Callaghan, R.W.

    1996-04-01

    The purpose of this National Ignition Facility Acquisition Plan is to describe the overall procurement strategy planned for the National Ignition Facility (NIF) Project. The scope of the plan describes the procurement activities and acquisition strategy for the following phases of the NIF Project, each of which receives either plant and capital equipment (PACE) or other project cost (OPC) funds: Title 1 and 2 design and Title 3 engineering (PACE); Optics manufacturing facilitization and pilot production (OPC); Convention facility construction (PACE); Procurement, installation, and acceptance testing of equipment (PACE); and Start-up (OPC). Activities that are part of the base Inertial Confinement Fusion (ICF) Program are not included in this plan. The University of California (UC), operating Lawrence Livermore National Laboratory (LLNL) and Los Alamos National Laboratory, and Lockheed-Martin, which operates Sandia National Laboratory (SNL) and the University of Rochester Laboratory for Laser Energetics (UR-LLE), will conduct the acquisition of needed products and services in support of their assigned responsibilities within the NIF Project structure in accordance with their prime contracts with the Department of Energy (DOE). LLNL, designated as the lead Laboratory, will have responsibility for all procurements required for construction, installation, activation, and startup of the NIF

  8. Forced Ignition Study Based On Wavelet Method

    Science.gov (United States)

    Martelli, E.; Valorani, M.; Paolucci, S.; Zikoski, Z.

    2011-05-01

    The control of ignition in a rocket engine is a critical problem for combustion chamber design. Therefore it is essential to fully understand the mechanism of ignition during its earliest stages. In this paper the characteristics of flame kernel formation and initial propagation in a hydrogen-argon-oxygen mixing layer are studied using 2D direct numerical simulations with detailed chemistry and transport properties. The flame kernel is initiated by adding an energy deposition source term in the energy equation. The effect of unsteady strain rate is studied by imposing a 2D turbulence velocity field, which is initialized by means of a synthetic field. An adaptive wavelet method, based on interpolating wavelets is used in this study to solve the compressible reactive Navier- Stokes equations. This method provides an alternative means to refine the computational grid points according to local demands of the physical solution. The present simulations show that in the very early instants the kernel perturbed by the turbulent field is characterized by an increased burning area and a slightly increased rad- ical formation. In addition, the calculations show that the wavelet technique yields a significant reduction in the number of degrees of freedom necessary to achieve a pre- scribed solution accuracy.

  9. A 1-D Study of the Ignition Space for Magnetic Indirect (X-ray) Drive Targets

    Energy Technology Data Exchange (ETDEWEB)

    Cobble, James Allen [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Sinars, Daniel Brian [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2016-06-02

    The ICF program today is investigating three approaches to achieving multi-MJ fusion yields and ignition: (1) laser indirect (x-ray) drive on the National Ignition Facility (NIF), (2) laser direct drive (primarily on the Omega laser facility at the University of Rochester), and (3) magnetic direct drive on the Z pulsed power facility. In this white paper we briefly consider a fourth approach, magnetic indirect drive, in which pulsedpower- driven x-ray sources are used in place of laser driven sources. We first look at some of the x-ray sources studied on Z prior to 2007 before the pulsed power ICF program shifted to magnetic direct drive. We then show results from a series of 1D Helios calculations of double-shell capsules that suggest that these sources, scaled to higher temperatures, could be a promising path to achieving multi-MJ fusion yields and ignition. We advocate here that more detailed design calculations with widely accepted 2D/3D ICF codes should be conducted for a better assessment of the prospects.

  10. Technical training - Places available

    CERN Document Server

    2012-01-01

    If you would like more information on a course, or for any other inquiry/suggestions, please contact Technical.Training@cern.ch Valeria Perez Reale, Learning Specialist, Technical Programme Coordinator (Tel.: 62424) Eva Stern and Elise Romero, Technical Training Administration (Tel.: 74924)   Electronics design Next Session Duration Language Availability Certified LabVIEW Associate Developer (CLAD) 06-Dec-12 to 06-Dec-12 1 hour English One more place available Compatibilité électromagnetique (CEM): Applications 23-Nov-12 to 23-Nov-12 3.5 hours English 3 places available Compatibilité électromagnétique (CEM): Introduction 23-Nov-12 to 23-Nov-12 3 hours English 43 places available Effets des Radiations sur les composants et systèmes électroniques 11-Dec-12 to 12-Dec-12 1 day 4 hours French 9 places available LabVIEW for beginners ...

  11. History, Criticism and Place

    DEFF Research Database (Denmark)

    Hinds, Mat; Carter, Adrian; Malpas, Jeff

    2012-01-01

    Rory Spence and Richard Leplastrier shared a conversation and friendship that lasted 20years until Spence's death in 2004. The discussions focused largely upon issues of place, distilled through the practice of Leplastrier....

  12. Marine Place Names

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains the geographic place names for features in the U.S territorial waters and outer continental shelf. These names can be used to find or define a...

  13. Deriving forest fire ignition risk with biogeochemical process modelling.

    Science.gov (United States)

    Eastaugh, C S; Hasenauer, H

    2014-05-01

    Climate impacts the growth of trees and also affects disturbance regimes such as wildfire frequency. The European Alps have warmed considerably over the past half-century, but incomplete records make it difficult to definitively link alpine wildfire to climate change. Complicating this is the influence of forest composition and fuel loading on fire ignition risk, which is not considered by purely meteorological risk indices. Biogeochemical forest growth models track several variables that may be used as proxies for fire ignition risk. This study assesses the usefulness of the ecophysiological model BIOME-BGC's 'soil water' and 'labile litter carbon' variables in predicting fire ignition. A brief application case examines historic fire occurrence trends over pre-defined regions of Austria from 1960 to 2008. Results show that summer fire ignition risk is largely a function of low soil moisture, while winter fire ignitions are linked to the mass of volatile litter and atmospheric dryness.

  14. Deriving forest fire ignition risk with biogeochemical process modelling☆

    Science.gov (United States)

    Eastaugh, C.S.; Hasenauer, H.

    2014-01-01

    Climate impacts the growth of trees and also affects disturbance regimes such as wildfire frequency. The European Alps have warmed considerably over the past half-century, but incomplete records make it difficult to definitively link alpine wildfire to climate change. Complicating this is the influence of forest composition and fuel loading on fire ignition risk, which is not considered by purely meteorological risk indices. Biogeochemical forest growth models track several variables that may be used as proxies for fire ignition risk. This study assesses the usefulness of the ecophysiological model BIOME-BGC's ‘soil water’ and ‘labile litter carbon’ variables in predicting fire ignition. A brief application case examines historic fire occurrence trends over pre-defined regions of Austria from 1960 to 2008. Results show that summer fire ignition risk is largely a function of low soil moisture, while winter fire ignitions are linked to the mass of volatile litter and atmospheric dryness. PMID:26109905

  15. Variable valve timing in a homogenous charge compression ignition engine

    Science.gov (United States)

    Lawrence, Keith E.; Faletti, James J.; Funke, Steven J.; Maloney, Ronald P.

    2004-08-03

    The present invention relates generally to the field of homogenous charge compression ignition engines, in which fuel is injected when the cylinder piston is relatively close to the bottom dead center position for its compression stroke. The fuel mixes with air in the cylinder during the compression stroke to create a relatively lean homogeneous mixture that preferably ignites when the piston is relatively close to the top dead center position. However, if the ignition event occurs either earlier or later than desired, lowered performance, engine misfire, or even engine damage, can result. The present invention utilizes internal exhaust gas recirculation and/or compression ratio control to control the timing of ignition events and combustion duration in homogeneous charge compression ignition engines. Thus, at least one electro-hydraulic assist actuator is provided that is capable of mechanically engaging at least one cam actuated intake and/or exhaust valve.

  16. Ignition in net for different energy confinement time scalings

    International Nuclear Information System (INIS)

    Johner, J.; Prevot, F.

    1988-06-01

    A zero-dimensional profile dependent model is used to assess the feasibility of ignition in the extended version of NET. Five recent scalings for the energy confinement time (Goldston, Kaye All, Kaye Big, Shimomura-Odajima, Rebut-Lallia) are compared in the frame of two different scenarii, i.e., H-mode with a flat density profile or L-mode with a peaked density profile. For the flat density H-mode case, ignition is accessible with none of the scalings except Rebut-Lallia's. For the peaked density L-mode case, ignition is accessible with none of the scalings except Rebut-Lallia's. For the two Kaye's scalings, ignition is forbidden in H-mode even with the peaked density profile. For the Rebut-Lallia scaling, ignition is allowed in L-mode even with the flat density profile

  17. Self-Placing Concrete

    OpenAIRE

    ECT Team, Purdue

    2007-01-01

    Certain concrete pours have areas where the congestion of reinforcing bars make placement of concrete almost impossible. Using conventional placing and vibration techniques, the resulting concrete can have considerable honeycombing due to the development of voids. Self-placing concrete is a possible solution to the problem. Also known as self-compactable concrete, self-consolidating concrete, flowable concrete, and non-vibration concrete. These concretes eliminate the need for vibration in a ...

  18. 'A Place to Sit'

    DEFF Research Database (Denmark)

    Hvejsel, Marie Frier; Klok, Julie Skovgaard; Bøhnke, Mia Marker

    Published in 2014 on the occasion of the third 'A Place to Sit' exhibition as a reflection upon three years of teaching tectonic method in architecture using the furniture scale as a learning basis.......Published in 2014 on the occasion of the third 'A Place to Sit' exhibition as a reflection upon three years of teaching tectonic method in architecture using the furniture scale as a learning basis....

  19. Technical training - Places available

    CERN Multimedia

    2012-01-01

    If you would like more information on a course, or for any other inquiry/suggestions, please contact Technical.Training@cern.ch Valeria Perez Reale, Learning Specialist, Technical Programme Coordinator (Tel.: 62424) Eva Stern and Elise Romero, Technical Training Administration (Tel.: 74924) HR Department Electronic Design Next Session Duration Language Availability Comprehensive VHDL for FPGA Design 08-Oct-12 to 12-Oct-12 5 days English 4 places Electrostatique / Protection ESD 28-Sep-12 to 28-Sep-12 3 hours French 25 places Impacts de la suppression du plomb (RoHS) en électronique 26-Oct-12 to 26-Oct-12 8 hours French 14 places Introduction to VHDL 10-Oct-12 to 11-Oct-12 2 days English 9 places LabVIEW Real Time and FPGA 13-Nov-12 to 16-Nov-12 5 days French 5 places LabVIEW for Experts 24-Sep-12 to 28-Sep-12 5 days English 6 places LabVIEW for beginners 15-Oct-12 to 17-...

  20. Weathering Patterns of Ignitable Liquids with the Advanced Distillation Curve Method.

    Science.gov (United States)

    Bruno, Thomas J; Allen, Samuel

    2013-01-01

    One can take advantage of the striking similarity of ignitable liquid vaporization (or weathering) patterns and the separation observed during distillation to predict the composition of residual compounds in fire debris. This is done with the advanced distillation curve (ADC) metrology, which separates a complex fluid by distillation into fractions that are sampled, and for which thermodynamically consistent temperatures are measured at atmospheric pressure. The collected sample fractions can be analyzed by any method that is appropriate. Analytical methods we have applied include gas chromatography (with flame ionization, mass spectrometric and sulfur chemiluminescence detection), thin layer chromatography, FTIR, Karl Fischer coulombic titrimetry, refractometry, corrosivity analysis, neutron activation analysis and cold neutron prompt gamma activation analysis. We have applied this method on product streams such as finished fuels (gasoline, diesel fuels, aviation fuels, rocket propellants), crude oils (including a crude oil made from swine manure) and waste oils streams (used automotive and transformer oils). In this paper, we present results on a variety of ignitable liquids that are not commodity fuels, chosen from the Ignitable Liquids Reference Collection (ILRC). These measurements are assembled into a preliminary database. From this selection, we discuss the significance and forensic application of the temperature data grid and the composition explicit data channel of the ADC.