SKI's and SSI's review of SKB's safety report SR-Can

International Nuclear Information System (INIS)

Dverstorp, Bjoern; Stroemberg, Bo

2008-03-01

This report summarises SKI's and SSI's joint review of the Swedish Nuclear Fuel and Waste Management Co's (SKB) safety report SR-Can (SKB TR-06-09). SR-Can is the first assessment of post-closure safety for a KBS-3 spent nuclear fuel repository at the candidate sites Forsmark and Laxemar, respectively. The analysis builds on data from the initial stage of SKB's surface-based site investigations and on data from full-scale manufacturing and testing of buffer and copper canisters. SR-Can can be regarded as a preliminary version of the safety report that will be required in connection with SKB's planned licence application for a final repository in late 2009. The main purpose of the authorities' review is to provide feedback to SKB on their safety reporting as part of the pre-licensing consultation process. However, SR-Can is not part of the formal licensing process. In support of the authorities' review three international peer review teams were set up to make independent reviews of SR-Can from three perspectives, namely integration of site data, representation of the engineered barriers and safety assessment methodology, respectively. Further, several external experts and consultants have been engaged to review detailed technical and scientific issues in SR-Can. The municipalities of Oesthammar and Oskarshamn where SKB is conducting site investigations, as well NGOs involved in SKB's programme, have been invited to provide their views on SR-Can as input to the authorities' review. Finally, the authorities themselves, and with the help of consultants, have used independent models to reproduce part of SKB's calculations and to make complementary calculations. All supporting review documents are published in SKI's and SSI's report series. The main findings of the review are: -SKB's safety assessment methodology is overall in accordance with applicable regulations, but part of the methodology needs to be further developed for the licence application. -SKB's quality

Review of data types for the SKB site investigation programme

Energy Technology Data Exchange (ETDEWEB)

Klos, Richard

2002-11-01

SKB is currently undertaking a detailed site investigation programme (SIP) to characterise the geology and surface ecosystems in areas around potential sites for a planned repository for spent nuclear fuel. This report reviews site specific and generic data types needed to characterise biosphere processes relevant to the evaluation of long-term radiological safety in the context of assessments of future impacts arising from the deep geologic disposal of spent nuclear fuel. Focus is on the types of data that make up the different elements of radiological assessment models and how the data used relate to site-specific characteristics. The relevance of the SIP to the development of assessment models for long-term assessment is addressed, including the representation of the geosphere-biosphere interface. Reference to SKB's programme is made in order to determine how well the current programme will meet the needs of assessment models that will be developed and used in the assessment of long-term safety. The review also provides SSI with a basis for the planning of further SSI R and D work. The process, by which site-specific information is converted into a form suitable for use in numerical assessment models, can be quite complex. An overview of assessment model concepts is provided and the links between these and real-word site information considered. Focusing on the needs of assessment models, the review provides a summary of the main types of analyses and site-specific models that are needed for safety evaluations. Review of the SIP indicates that information from the programme feeds into a set of detailed site description models. However there is a gap between the descriptive components and the detailed model descriptions needed to configure numerical assessment models. Details of system evolution are not clearly dealt with in the programme. The SIP focuses on a detailed description of the site the present day. However, radiological impacts are not expected to

Review of data types for the SKB site investigation programme

International Nuclear Information System (INIS)

Klos, Richard

2002-11-01

SKB is currently undertaking a detailed site investigation programme (SIP) to characterise the geology and surface ecosystems in areas around potential sites for a planned repository for spent nuclear fuel. This report reviews site specific and generic data types needed to characterise biosphere processes relevant to the evaluation of long-term radiological safety in the context of assessments of future impacts arising from the deep geologic disposal of spent nuclear fuel. Focus is on the types of data that make up the different elements of radiological assessment models and how the data used relate to site-specific characteristics. The relevance of the SIP to the development of assessment models for long-term assessment is addressed, including the representation of the geosphere-biosphere interface. Reference to SKB's programme is made in order to determine how well the current programme will meet the needs of assessment models that will be developed and used in the assessment of long-term safety. The review also provides SSI with a basis for the planning of further SSI R and D work. The process, by which site-specific information is converted into a form suitable for use in numerical assessment models, can be quite complex. An overview of assessment model concepts is provided and the links between these and real-word site information considered. Focusing on the needs of assessment models, the review provides a summary of the main types of analyses and site-specific models that are needed for safety evaluations. Review of the SIP indicates that information from the programme feeds into a set of detailed site description models. However there is a gap between the descriptive components and the detailed model descriptions needed to configure numerical assessment models. Details of system evolution are not clearly dealt with in the programme. The SIP focuses on a detailed description of the site the present day. However, radiological impacts are not expected to reach

Quality Assurance Review of SKB's Copper Corrosion Experiments

Energy Technology Data Exchange (ETDEWEB)

Baldwin, Tamara D.; Hicks, Timothy W. (Galson Sciencies LTD. 5 Grosvenor House, Melton Road, Oakham (United Kingdom))

2010-06-15

SKB is preparing a license application for the construction of a final repository for spent nuclear fuel in Sweden. This application will be supported by the safety assessment SR-Site for the post-closure phase. The assessment of long-term safety is based on a broad range of experimental results from laboratory scale, intermediate scale and up to full scale experiments. It is essential that there is a satisfactory level of assurance that experiments have been carried out with sufficient quality, so that results can be considered to be reliable within the context of their use in safety assessment. The former named authority, SKI, has initiated a series of reviews of SKB's methods of quality assurance and their implementation. This quality assurance review is focused on the work of copper corrosion being conducted in at SKB's Hard Rock Laboratory (HRL) in Aespoe, LOT and Miniature canister (Minican) experiments. In order for the reviewers to get a broad understanding of the issue of copper corrosion both SKB reports as well as the viewpoint of MKG was collected prior to commencement of the actual review task. The purpose of this project is to assess SKB's quality assurance with the view of providing input for the preparation of the SR-Site safety assessment. This has been achieved by examination of the corrosion part of the LOT and Minican experiments using a check list, visits to the relevant facilities, and meetings with contractors and a few members of the SKB staff. The same approach for quality assurance reviews has been used earlier in similar review tasks. During the quality review of the selected projects, several QA- related issues of different degree of severity was noted by the reviewers. The most significant finding was that SKB has chosen to present only selected real-time corrosion monitoring data in TR-09-20. This was surprising and SSM expect that SKB will analyse the reason for this thoroughly. The reviewers also made other

SSI's review of SKB's RD and D programme 2001

Energy Technology Data Exchange (ETDEWEB)

Hedberg, Bjoern; Larsson, Carl-Magnus; Wiebert, Anders [and others

2002-08-01

In the report SSI's review of SKB's RD and D programme 2001 is presented. In the review SSI comments, among other things, the decision making process, the need for a strategy document, SKB's safety and system analysis and SKB's biosphere studies.

Near field studies within the SKB 91 Project

International Nuclear Information System (INIS)

Widen, H.; Bengtsson, A.; Grundfelt, B.

1991-06-01

A number of near field studies was preformed during the early part of the SKB91 project. This report summaries this work and includes: - Simulation of the steady release from the near field with different time for canister penetration. - Simulation of the release from a repository with 5300 canisters with different penetration times for different parts of the canisters due to manufacturing error, glaciations, inner over pressure and corrosion. - Calculation with a numerical model of the transient release of the instantaneously dissolvable species and the effect of different boundary conditions both at the canister/bentonite and the bentonite/rock interface. - Description of the implementation of a resistance network model for the calculation of the steady state transport resistances in the different pathways from the canisters. - Comparison of two analytical models for the calculation of the release of the instantaneously dissolvable species. (au)

Review of SKB's Quality Assurance Programme

Energy Technology Data Exchange (ETDEWEB)

Baldwin, Tamara D.; Hicks, Timothy W. (Galson Sciences LTD, Oakham, Rutland (United Kingdom))

2009-06-15

SKB is preparing a license application for the construction of a final repository for spent nuclear fuel in Sweden. This application will be supported by the safety assessment SR-Site for the post-closure phase. The assessment of long-term safety is based on a broad range of experimental results from laboratory scale, intermediate scale and up to full scale experiments. It is essential that there is a satisfactory level of assurance that experiments have been carried of with sufficient quality, so that results can be considered to be reliable within the context of their use in safety assessment. SSM has initiated a series of reviews of SKB's methods of quality assurance and their implementation. This project includes reviews of the quality assurance (QA) procedures and instructions that have been prepared for the SR-Site assessment as well as reviews of QA implementation at the canister and buffer/backfill laboratories in Oskarshamn, Sweden. The purpose of this project is to assess SKB's quality assurance with the view of providing a good basis for subsequent quality reviews in the context of future licensing. This has been achieved by examination of a number of SKB experiments using a check list, visits to the relevant facilities, and meetings with contractors and a few members of the SKB staff. Overall, the reviewed set of QA documents and instructions do provide reasonably comprehensive coverage of quality-affecting issues relating to the SR-Site safety assessment and, if implemented correctly, will generate confidence in the reliability of the safety assessment results. The results show that the efforts involving quality assurance are increasing within the SKB programme and in general appear to be satisfactory for ongoing experiments and measurements. However, progress in development of the QA documents and instructions has been relatively recent and it may be difficult for these to be fully implemented in the short period remaining before the planned

Assessment of SKB's proposal for encapsulation; Granskning av SKB:s foerslag till inkapslingsteknik

Energy Technology Data Exchange (ETDEWEB)

Lundin, M.; Gustafsson, Oskar; Broemsen, B. von; Troell, E. [IVF Industriforskning och utveckling AB, Moelndal (Sweden)

2001-01-01

This report accounts for an independent assessment of a proposal regarding manufacturing of copper canisters, which has been presented by SKB (Swedish Nuclear Fuel and Waste Management Co) in cooperation with MABU Consulting. IVF (The Swedish Institute for Production Engineering Research) has performed the assessment by commission of SKI (Swedish Nuclear Power Inspectorate). IVF generally believe that the proposed method, recommended manufacturing equipment and organisation will most likely mean that a functioning manufacturing of canisters can be realised. No significant deficiencies have been identified, which would mean serious problems during the manufacturing process. In some cases IVF recommends a further evaluation regarding proposed methods and/or equipment. Basically these concerns the welding processes. However, it should be stressed that SKB has emphasised that further investigation will be performed regarding this subject. Furthermore IVF recommend that proposed methods and equipment for machining of copper cylinders and for blasting of inserts should be further evaluated.

SKI's and SSI's joint review of SKB's safety assessment report, SR 97. Summary

International Nuclear Information System (INIS)

2001-01-01

The Swedish Nuclear Fuel and Waste Management Co (SKB) has a programme for the siting of a repository for spent nuclear fuel in Swedish bedrock. In 1996, the Swedish Government decided that SKB must perform an assessment of the repository's long-term safety before undertaking the next step of the programme which entails drilling in a minimum of two municipalities (site investigations). SKB has presented such a safety assessment in SR 97 Post-closure Safety (henceforth referred to as SR 97). SR 97 is one of the documents in the comprehensive reporting that SKB must provide when it proposes sites for investigation. The Swedish Nuclear Power Inspectorate (SKI) and the Swedish Radiation Protection Institute (SSI) have evaluated SR 97 in terms of its purposes which are to demonstrate a methodology for safety assessment, to show that Swedish bedrock can provide a safe repository using SKB's method, to provide a basis for specifying the factors that are important for site selection and to derive preliminary requirements on the function of the engineered barriers. The authorities have reached the following conclusions: SR 97 does not indicate any conditions that would mean that geological final disposal in accordance with SKB's method would have significant deficiencies in relation to the safety and radiation protection requirements of the authorities. SR 97 contains the elements required for a comprehensive assessment of safety and radiation protection. SKB's safety assessment methodology has improved within several important areas, such as the documentation of processes and properties that can affect repository performance and the development of models for safety assessment calculations. The methodology used in SR 97 has some deficiencies, for example, the specification of future events to be described in the safety assessment. SR 97 has not, to an adequate extent, dealt with unfavourable conditions that can affect the future safety of a repository. SKB states that the

SKI's evaluation of SKB's Supplement to RD and D Programme 92

International Nuclear Information System (INIS)

1995-05-01

On December 16, 1993, the Government decided (M93/2525/6), with regard to the 1992 Programme for Research, Development, Demonstration and Other Measures (RD and D Programme 92), compiled by the Swedish Nuclear Fuel and Waste Management Co (SKB) in accordance with Section 12 of the Act on Nuclear Activities, that RD and D Programme 92 should be supplemented by SKB in the manner specified in the decision. On August 19, 1992, SKB submitted the requested supplement to the Swedish Nuclear Power Inspectorate (SKI). SKI has examined the supplement and has requested and obtained comments from a large number of reviewing bodies. SKI hereby submits the documents on the matter along with its own review report. The review report contains an evaluation of SKB's supplement in relation to the government decision and certain recommendations for the structuring of the licensing procedure for planned facilities. These recommendations have taken into account the statements of the reviewing bodies

Kontribusi Motivasi Kerja dan Insentif terhadap Kinerja Pamong Belajar di SKB Kota Padang

Directory of Open Access Journals (Sweden)

Angre Dodi

2016-12-01

Full Text Available Based on the phenomenon in the field is seen that the performance of officials in SKB city of Padang is still a problem tutors poor performance of officials in lesson planning, lack of discipline officials in carrying out duties, poor performance of officials in the implementation of learning, low capacity of officials in mastering learning materials and lack of loyalty work pamong , This study aims to reveal: the contribution to the performance of work motivation SKB tutors in the city of Padang, the contribution to the performance incentive SKB tutors in the city of Padang, and the contribution of motivation and incentives together on the performance of tutors in SKB Padang. The research methodology used in this study is a quantitative method by using quantitative descriptive analysis approach. The population in this study were twenty five people and all sampled in this study. The data were analyzed using correlation techniques. Testing hypotheses using correlation and regression technique is simple and multiple regression assisted with SPSS version. The results showed: Work motivation to contribute to the performance of officials in the city of Padang SKB with the contribution of thirty-six point four percent. Incentives contribute to the performance of officials SKB Padang City with the amount of twenty-six point two percent. Motivation and incentives jointly contribute to the performance of officials in the city of Padang SKB fifty-five point two percent. It is clear that to improve the performance of officials is good and should ideally be done through motivation and incentives are adequate.

Evaluation of SKB/Posiva's report on the horizontal alternative of the KBS-3 method

International Nuclear Information System (INIS)

Apted, Michael J.; Bennet, David G.; Saario, Timtetr; Savage, David

2009-10-01

The KBS-3 method, based on multiple barriers, is the proposed spent fuel disposal method both in Sweden and Finland. The method has two design alternatives: the vertical (KBS-3V) and the horizontal (KBS-3H). In the KBS-3H concept, copper canisters loaded with spen nuclear fuel are encased in a compacted bentonite buffer with an outer supporting supercontainer composed of a mild steel basket, and the entire supercontainer is emplaced horizontally in long emplacement drifts. SKB and Posiva have conducted a joint research, development and demonstration (RDandD) programme in 2002-2007 with the overall aim of establishing whether the KBS-3H represents a feasible alternative to the reference alternative KBS-3V. The objectives have been to demonstrate that the horizontal deposition alternative is technically feasible and that it fulfils the same long-term safety requirement as the KBS-3V. Swedish Radiation Safety Authority (SSM) considers that it is a proper time to evaluate the work carried by SKB and Posiva when this period of joint research is ended and a relatively complete set of reporting is available. SSM therefore required its external expert group BRITE (the Barrier Review, Integration, Tracking and Evaluation) to evaluate the reporting. The aims of the evaluation are to investigate the differences between the horizontal and vertical design alternatives with respect to: Completeness: has SKB/Posiva identified the full set of key topics, and if not, what additional specific key topics should be evaluated; Depth-of-treatment: has SKB/Posiva analysed the key topics in sufficient depth, and if not, on what specific aspects in more detailed consideration required; Status of information: has SKB/ Posiva provided enough information on the current status of knowledge and uncertainties that impact the understanding of each key topic, and if not, what further information should be cited; Feasibility and practicality: for key issues related to the fabrication and

SKB annual report 1991. Including summaries of technical reports issued during 1991

International Nuclear Information System (INIS)

1992-05-01

This is the annual report on the activities of the Swedish Nuclear Fuel and Waste Management Co., SKB. SKB is the owner of CLAB, the central facility for interim storage of spent nuclear fuel, located at Oskarshamn. CLAB was taken into operation in July 1985 and to the end of 1991 in total 1514 tonnes of spent fuel (measured as uranium) have been received. Transportation from the nuclear sites to CLAB is made by a special ship, M/S Sigyn. At Forsmark the final repository for Radioactive Waste (SFR) was taken into operation in April 1988. The repository is situated in crystalline rock under the Baltic Sea. The first construction phase includes rock caverns for 60000 m 3 of waste. A second phase for additional 30000 m 3 is planned to be built and commissioned around the year 2000. At the end of 1991 a total of 7900 m 3 of waste have been deposited in SFR. SKB is in charge of a comprehensive research and development programme on geological disposal of nuclear waste. The total cost for R and D during 1991 was 182.7 MSEK of which 15.9 MSEK came from participants outside Sweden. Geological site-investigations are a substantial part of the programme. SKB is also the managing participant of the international Stripa-project under OECD/NEA. Cost calculations for the total nuclear waste management system, including decommissioning of all reactors, are updated annually. The total cost is estimated to 55 billion SEK. SKB also handles matters pertaining to prospecting and enrichment as well as stockpiling of uranium as strategic reserves for the Swedish nuclear power industry. Consulting service from SKB and associated expert groups are available on a commercial basis. Information activities are an integrated and important part of the Swedish radioactive waste management system. During 1991 successful public information activities have been carried out using mobile exhibitions in a tailor-made trailer and on the SKB ship M/S Sigyn. (au)

Assessment of SKB's proposal for encapsulation

International Nuclear Information System (INIS)

Lundin, M.; Gustafsson, Oskar; Broemsen, B. von; Troell, E.

2001-01-01

This report accounts for an independent assessment of a proposal regarding manufacturing of copper canisters, which has been presented by SKB (Swedish Nuclear Fuel and Waste Management Co) in cooperation with MABU Consulting. IVF (The Swedish Institute for Production Engineering Research) has performed the assessment by commission of SKI (Swedish Nuclear Power Inspectorate). IVF generally believe that the proposed method, recommended manufacturing equipment and organisation will most likely mean that a functioning manufacturing of canisters can be realised. No significant deficiencies have been identified, which would mean serious problems during the manufacturing process. In some cases IVF recommends a further evaluation regarding proposed methods and/or equipment. Basically these concerns the welding processes. However, it should be stressed that SKB has emphasised that further investigation will be performed regarding this subject. Furthermore IVF recommend that proposed methods and equipment for machining of copper cylinders and for blasting of inserts should be further evaluated

SKB annual report 1993. Including summaries of technical reports issued during 1993

International Nuclear Information System (INIS)

1994-05-01

This is the annual report on the activities of the Swedish Nuclear and Waste Management Co., SKB. It contains in part I an overview of SKB activities in different fields. Part II gives a description of the research and development work on nuclear waste disposal performed during 1993. Lectures and publications during 1993 as well as reports issued in the SKB technical series are listed in part III. Part IV contains the summaries of all technical reports issued during 1993. SKB is the owner of CLAB, the Central Facility for Interim Storage of Spent Nuclear Fuel, located at Oskarshamn. CLAB was taken into operation in July 1985 and to the end of 1993 in total 1 885 tonnes of spent fuel (measured as uranium) have been received. Transportation from the nuclear sites to CLAB is made by a special ship, M/S Sigyn. At Forsmark the final repository for Radioactive Waste - SFR - was taken into operation in April 1988. The repository is situated in crystalline rock under the Baltic Sea. At the end of 1993 a total of 13 000 m 3 of waste have been deposited in SFR. SKB is in charge of a comprehensive research and development programme on geological disposal of nuclear waste. Some of the main areas for SKB research are: Groundwater movements; Bedrock stability; Groundwater chemistry and nuclide migration; Methods and instruments for in situ characterization of crystalline bedrock; Characterization and leaching of spent nuclear fuel; Properties of bentonite for buffer, backfilling and sealing; Radionuclide transport in biosphere and dose evaluations; Development of performance and safety assessment methodology and assessment models; Construction of an underground research laboratory

SKI's and SSI's comments on SKB's RandD/RDandD Programme 1986-2007; SKI:s och SSI:s synpunkter paa SKB:s FoU/Fud-program 1986-2007

Energy Technology Data Exchange (ETDEWEB)

Toverud, Oeivind (Bromma Geokonsult (Sweden))

2010-10-15

SKB has since 1986 submitted RDandD program every three years to former Nuclear Power Inspectorate (SKI) for review and evaluation. SKI and former Radiation Protection Inst. (SSI) have commented on a large number of issues in connection with the audits. The authorities' goal has been to influence the SKB's design of the RDandD programs, inter alia with a view to future repository applications to fulfill the requirements they are tested against. SKB plans to submit applications for the final repository for spent Fuel first quarter of 2011 and it is therefore important for Radiation Safety Authority (SSM) to follow up on SKB's handling of critical comments on RDandD programs. A starting point for this monitoring is to establish how SKB has dealt with major issues raised by authorities in the audits of the RDandD programs and in consultation process which has been linked to the programs. The follow-up is expected to be an important contribution to the planning and implementation of the examination of applications for nuclear fuel repository

Dealing with the current permissibility application for constructing a spent fuel DGR in Sweden. SKB's license applications for a spent fuel repository

International Nuclear Information System (INIS)

Olsson, Olle

2014-01-01

The nuclear power utilities in Sweden were in 1976 obliged to demonstrate a safe method for final disposal of spent fuel in order to start operation of new reactors. This initiated a comprehensive research, development and demonstration programme and the development of the KBS-method for final disposal. A new Nuclear Activities Act in 1984 gave the reactor owners full technical and financial responsibility for the waste. They gave in turn SKB the responsibility for all nuclear waste management. Reprocessing was no longer required and direct disposal of the spent fuel has, since then, been the main alternative. Alternative methods for final disposal have been evaluated and compared to the KBS-3-method but it has remained the preferred alternative. A comprehensive research, development and demonstration programme to strengthen the scientific basis and to refine the KBS-3-method has been operated by SKB since then. The site selection process for the final repository for spent nuclear fuel was initiated in 1992. The work included general siting studies at the national and the municipal level and in 2002, SKB initiated site investigations for siting of a final repository on two sites: the Simpevarp and Laxemar areas and the Forsmark area. At the same time, the work on preparing license applications to construct and operate an encapsulation plant and a final repository for spent fuel was started. In June 2009, SKB announced Forsmark as the selected site for the final repository. This paper reviews the applicable legislation and describes the license application, the licensing review and the preparations for implementation

Evaluation of SKB/Posiva's report on the horizontal alternative of the KBS-3 method

Energy Technology Data Exchange (ETDEWEB)

Apted, Michael J.; Bennet, David G.; Saario, Timtetr; Savage, David

2009-10-15

The KBS-3 method, based on multiple barriers, is the proposed spent fuel disposal method both in Sweden and Finland. The method has two design alternatives: the vertical (KBS-3V) and the horizontal (KBS-3H). In the KBS-3H concept, copper canisters loaded with spen nuclear fuel are encased in a compacted bentonite buffer with an outer supporting supercontainer composed of a mild steel basket, and the entire supercontainer is emplaced horizontally in long emplacement drifts. SKB and Posiva have conducted a joint research, development and demonstration (RDandD) programme in 2002-2007 with the overall aim of establishing whether the KBS-3H represents a feasible alternative to the reference alternative KBS-3V. The objectives have been to demonstrate that the horizontal deposition alternative is technically feasible and that it fulfils the same long-term safety requirement as the KBS-3V. Swedish Radiation Safety Authority (SSM) considers that it is a proper time to evaluate the work carried by SKB and Posiva when this period of joint research is ended and a relatively complete set of reporting is available. SSM therefore required its external expert group BRITE (the Barrier Review, Integration, Tracking and Evaluation) to evaluate the reporting. The aims of the evaluation are to investigate the differences between the horizontal and vertical design alternatives with respect to: Completeness: has SKB/Posiva identified the full set of key topics, and if not, what additional specific key topics should be evaluated; Depth-of-treatment: has SKB/Posiva analysed the key topics in sufficient depth, and if not, on what specific aspects in more detailed consideration required; Status of information: has SKB/ Posiva provided enough information on the current status of knowledge and uncertainties that impact the understanding of each key topic, and if not, what further information should be cited; Feasibility and practicality: for key issues related to the fabrication and

Development of the KBS-3 method. Survey of SKB's research programs and safety assessments, reviews by Government authorities and SKB's international research cooperation

International Nuclear Information System (INIS)

2010-11-01

The purpose of this report is to outline the origin and development over the past 30 years (up to 2009) of the KBS-3 method proposed by the Swedish Nuclear Fuel and Waste Management Co (SKB) for final disposal of spent nuclear fuel. The KBS-3 method is based on three protective barriers. The spent nuclear fuel is encapsulated in impermeable copper canisters. The canisters are placed in crystalline basement rock at a depth of 400-700 metres, embedded in bentonite clay. After disposal the tunnels and rock caverns are sealed. The account does not claim to cover all parts of the extensive technical and scientific research and development work conducted by SKB in form of collecting data, refining methods and increasing process understanding. The report forms part of the background material which SKB has gathered as a basis for future applications regarding permits under the Environmental Code and the Nuclear Activities Act to build and operate facilities for encapsulation and final disposal of spent nuclear fuel. A prominent feature of the industrial development work on the final disposal of spent nuclear fuel has been an openness for a constant input of ideas and opinions from society and public bodies (the Government, national authorities, universities and other institutes of higher education, municipalities and various non-governmental organizations). The presentation sheds light on developments in a number of areas that are of central importance for safety in a KBS-3 repository. In SKB's RDandD Programme 2007, these areas go under the headings rock line, buffer line, canister line, backfilling line and closure line. Furthermore, attention has been given to issues related to the possible retrieval of deposited canisters, variants of KBS-3, deposition technology and safety assessment, as well as a number of interdisciplinary issues. The development of methods for the safety assessment has been an important part of the development of the KBS-3 method. The work with

SKB Annual Report 1994. Including summaries of technical reports issued during 1994

International Nuclear Information System (INIS)

1995-05-01

The report gives an overview of SKB activities in different fields, and a description of R and D on nuclear waste disposal performed during 1994. SKB is in charge of a comprehensive program on geological disposal of nuclear waste. The total cost for R and D 1994 was 186 MSEK of which 59 MSEK were investments in the Aespoe Hard Rock Laboratory. Some of the main areas for SKB research are: Groundwater movements; Bedrock stability; Groundwater chemistry and nuclide migration; Methods and instruments for in situ characterization of crystalline bedrock; Characterization and leaching of spent fuel; Properties of bentonite for buffer, backfilling and sealing; Radionuclide transport in biosphere and dose evaluation; Development of performance and safety assessment methodology and assessment models; Construction of an underground research laboratory. 66 figs, 6 tabs

SKB Annual Report 1994. Including summaries of technical reports issued during 1994

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-05-01

The report gives an overview of SKB activities in different fields, and a description of R and D on nuclear waste disposal performed during 1994. SKB is in charge of a comprehensive program on geological disposal of nuclear waste. The total cost for R and D 1994 was 186 MSEK of which 59 MSEK were investments in the Aespoe Hard Rock Laboratory. Some of the main areas for SKB research are: Groundwater movements; Bedrock stability; Groundwater chemistry and nuclide migration; Methods and instruments for in situ characterization of crystalline bedrock; Characterization and leaching of spent fuel; Properties of bentonite for buffer, backfilling and sealing; Radionuclide transport in biosphere and dose evaluation; Development of performance and safety assessment methodology and assessment models; Construction of an underground research laboratory. 66 figs, 6 tabs.

The feasibility of Backfilling a Repository of Spent Fuel: An Assessment of Recent Developments by SKB

International Nuclear Information System (INIS)

Bennett, David

2010-12-01

In the Review Statement and Evaluation of SKB's RDandD programme 2007 (SKI Report 2008:48E), the former Swedish Nuclear Power Inspectorate (SKI) commented that considerable work remained to be done for knowledge of both practical management issues on backfilling and analysis of long-term backfill evolution to reach the same level as for the canister and the buffer. SKI considered that the backfill material had not been thoroughly reported in the RDandD programme. More concrete plans were also needed relating to large-scale demonstration experiments to investigate the performance of the backfill in as realistic conditions as possible. In the spring of 2009, noting that SKB had changed its concept for backfilling several times over the last few years, and after having visited SKB's most recent backfilling trials at Aespoe, both SSM and SSM's expert group BRITE had strong concerns regarding SKB's programme for backfilling the repository tunnels. Although the BRITE expert group has been keeping a watching brief over SKB's development work on backfilling, SSM has not undertaken a systematic assessment of SKB's work in this area since the SR-Can Safety Report was reviewed in 2006. Dr David Bennett, a member and secretary of the BRITE expert group, was asked to do such an assessment. This report describes the assessment results

The feasibility of Backfilling a Repository of Spent Fuel: An Assessment of Recent Developments by SKB

Energy Technology Data Exchange (ETDEWEB)

Bennett, David (TerraSalus Limited, Rutland (United Kingdom))

2010-12-15

In the Review Statement and Evaluation of SKB's RDandD programme 2007 (SKI Report 2008:48E), the former Swedish Nuclear Power Inspectorate (SKI) commented that considerable work remained to be done for knowledge of both practical management issues on backfilling and analysis of long-term backfill evolution to reach the same level as for the canister and the buffer. SKI considered that the backfill material had not been thoroughly reported in the RDandD programme. More concrete plans were also needed relating to large-scale demonstration experiments to investigate the performance of the backfill in as realistic conditions as possible. In the spring of 2009, noting that SKB had changed its concept for backfilling several times over the last few years, and after having visited SKB's most recent backfilling trials at Aespoe, both SSM and SSM's expert group BRITE had strong concerns regarding SKB's programme for backfilling the repository tunnels. Although the BRITE expert group has been keeping a watching brief over SKB's development work on backfilling, SSM has not undertaken a systematic assessment of SKB's work in this area since the SR-Can Safety Report was reviewed in 2006. Dr David Bennett, a member and secretary of the BRITE expert group, was asked to do such an assessment. This report describes the assessment results

Joint SKI and SSI review of SKB preliminary safety assessment of repository for long-lived low- and intermediate-level waste. Review report

Energy Technology Data Exchange (ETDEWEB)

NONE

2001-03-01

SKI and SSI find that SKB's first proper safety assessment of the SFL 3-5 repositories provides a valuable springboard for continued efforts in this field. Even though the safety assessment is relatively limited in scope, it has numerous merits. The specific problems associated with the chosen repository concept for SFL 3-5 are discussed in a generally transparent manner. On the other hand, the authorities consider that SKB have only partly achieved the expressed goal of studying the significance of the current repository design and the choice of site. The greatest deficiency consists in that neither internal disturbances (such as considerable cracking or degradation of concrete structures) nor external disturbances (such as the effects of climate changes and glaciation) have been addressed in a thorough manner. A coherent report justifying the design choice from a long-term safety perspective is, in large part, not found here. SKI and SSI recommend that SKB provide a comparison with other possible SFL 3-5 repository designs. Depending upon, among other factors, what geospheric and biospheric conditions are assumed, SKB have shown that the calculated dose values could be relatively high for certain cases. More realistic assessments would be needed to draw reasonable comparisons between different sites, and to evaluate the importance of different nuclides in different contexts. Our review of SKBs preliminary safety assessment indicates that a great deal of research and development work remains to be done before the level of knowledge in this field is comparable with that associated with the final repository for spent fuel. This is reflected with unanimity in the international expert committee's review, and in the consultants' reviews. SKI and SSI wish to point out in particular the fact that comparison with SFR is of limited value, since the safety associated with SFL 3- 5 must be assessed on a much longer time scale. SKI and SSI find it remarkable

SKI's and SSI's review of SKB's safety report SR-Can

Energy Technology Data Exchange (ETDEWEB)

Dverstorp, Bjoern; Stroemberg, Bo (and others)

2008-03-15

This report summarises SKI's and SSI's joint review of the Swedish Nuclear Fuel and Waste Management Co's (SKB) safety report SR-Can (SKB TR-06-09). SR-Can is the first assessment of post-closure safety for a KBS-3 spent nuclear fuel repository at the candidate sites Forsmark and Laxemar, respectively. The analysis builds on data from the initial stage of SKB's surface-based site investigations and on data from full-scale manufacturing and testing of buffer and copper canisters. SR-Can can be regarded as a preliminary version of the safety report that will be required in connection with SKB's planned licence application for a final repository in late 2009. The main purpose of the authorities' review is to provide feedback to SKB on their safety reporting as part of the pre-licensing consultation process. However, SR-Can is not part of the formal licensing process. In support of the authorities' review three international peer review teams were set up to make independent reviews of SR-Can from three perspectives, namely integration of site data, representation of the engineered barriers and safety assessment methodology, respectively. Further, several external experts and consultants have been engaged to review detailed technical and scientific issues in SR-Can. The municipalities of Oesthammar and Oskarshamn where SKB is conducting site investigations, as well NGOs involved in SKB's programme, have been invited to provide their views on SR-Can as input to the authorities' review. Finally, the authorities themselves, and with the help of consultants, have used independent models to reproduce part of SKB's calculations and to make complementary calculations. All supporting review documents are published in SKI's and SSI's report series. The main findings of the review are: -SKB's safety assessment methodology is overall in accordance with applicable regulations, but part of the methodology needs to be

SSI's review of SKB's RDandD Program 2007

International Nuclear Information System (INIS)

Wiebert, Anders

2008-05-01

In this report, the Swedish Radiation Protection Authority (SSI) provides a review of the Swedish Nuclear Fuel and Waste Managements Company's (SKB) RDandD programme 2007. The report is a statement from SSI in the matter submitted earlier to SKI. In the review, SSI comments SKB's feedback to the continuous research and development program on the basis of the latest carried out safety analysis, SR-Can and the biosphere research. In the statement SSI points to a number of issues that need to be resolved before a licence application is handed in. SSI suggests that the Government asks for complements to the RDandD programme 2007. According to SSI, the programme concerning low and intermediate level waste and decommissioning of the nuclear power plants does not fulfil the requirements established by the Act on Nuclear Activities. Neither does the programme fulfil the expectations set by the Government decision regarding the RDandD programme 2004. SSI suggests that the programme should be complemented

Joint SKI and SSI review of SKB preliminary safety assessment of repository for long-lived low- and intermediate-level waste. Review report

International Nuclear Information System (INIS)

2001-03-01

SKI and SSI find that SKB's first proper safety assessment of the SFL 3-5 repositories provides a valuable springboard for continued efforts in this field. Even though the safety assessment is relatively limited in scope, it has numerous merits. The specific problems associated with the chosen repository concept for SFL 3-5 are discussed in a generally transparent manner. On the other hand, the authorities consider that SKB have only partly achieved the expressed goal of studying the significance of the current repository design and the choice of site. The greatest deficiency consists in that neither internal disturbances (such as considerable cracking or degradation of concrete structures) nor external disturbances (such as the effects of climate changes and glaciation) have been addressed in a thorough manner. A coherent report justifying the design choice from a long-term safety perspective is, in large part, not found here. SKI and SSI recommend that SKB provide a comparison with other possible SFL 3-5 repository designs. Depending upon, among other factors, what geospheric and biospheric conditions are assumed, SKB have shown that the calculated dose values could be relatively high for certain cases. More realistic assessments would be needed to draw reasonable comparisons between different sites, and to evaluate the importance of different nuclides in different contexts. Our review of SKBs preliminary safety assessment indicates that a great deal of research and development work remains to be done before the level of knowledge in this field is comparable with that associated with the final repository for spent fuel. This is reflected with unanimity in the international expert committee's review, and in the consultants' reviews. SKI and SSI wish to point out in particular the fact that comparison with SFR is of limited value, since the safety associated with SFL 3- 5 must be assessed on a much longer time scale. SKI and SSI find it remarkable that SKB have

Terminology report respect distance. The Use of the term respect distance in Posiva and SKB

International Nuclear Information System (INIS)

Lampinen, H.

2007-09-01

The term respect distance is used in some key publications of the Finnish Nuclear Waste Management Company, Posiva, and the Swedish Nuclear Waste Management Company, SKB (Svensk Kaernbrenslehantering). Posiva and SKB researchers use the same terms in their reports, and it is acknowledged that the terms used by both companies are not used in the same way, though the differences are often subtle. This report is a literature study of the term 'respect distance' and the terms immediately associated to it. Vital terms related to the respect distance and issues concerning the use of scale concepts in Posiva and SKB are gathered in the end of report. Posiva's respect distances consider the seismic, hydrological and mechanical properties of the deterministic deformation zones as important issues that constitute a risk for longterm safety. These requirements for respect distances are an interpretation of STUK's YVL 8.4 Guide. At present, Posiva's criteria regarding respect distances follow the instructions given in the Host Rock Classification system (HRC), whereas the size of a deformation zone to which respect distances are applied vary from the regional to local major and minor. This and other criteria that are given for respect distances may, however, change in the near future as Posiva's Rock Suitability Criteria (RSC) programme proceeds. SKB's considerations of respect distances acknowledge that the hydraulic and mechanical aspects of a deformation zone have an effect on the respect distance. However, the seismic risk is considered to overshadow the other effects on a regional scale. The respect distance defined for a deformation zone is coupled with the size of a fracture where secondary slip could occur. In the safety assessment it is assumed that this fracture cuts a deposition hole location. In SKB the respect distance is determined for regional and local major deformation zones. The trace length of such a zone is defined as being ≥ 3 km. For deformation zones

SKB's Project SAFE for the SFR 1 Repository. A Review by Consultants to SKI

International Nuclear Information System (INIS)

Chapman, N.A.; Maul, P.R.; Robinson, P.C.; Savage, D.

2002-06-01

The SFR 1 repository used for final disposal of low- and intermediate level radioactive waste produced by the Swedish nuclear power programme, industry, medicine and research. In 1992 it was granted a full-scale operating permit following additional reporting on long-term safety aspects by SKB, including the first in-depth safety assessment in 1991. It was stipulated as part of the full-scale licence for SFR 1 that a revised safety assessment should be carried out by SKB at least every ten years during the continued operation of the facility. The first 10-year SKB re-evaluation, called 'Project SAFE', was submitted to the regulators in 2001. The review of Project SAFE presented in this report is the culmination of several years' work with SKI including: 1. The extension and application of SKI's 'systems' approach to set up a description of the SFR 1 repository using Process Influence Diagrams (PIDs). 2. Participation in the development of a flexible Performance Assessment (PA) software tool (the AMBER code) that enables time-dependent analyses to be made of system behaviour. 3. Use of the PID database to explore, from first principles, issues that are likely to be important in the safety performance of SFR 1 and thereby to identify topics to be explored by PA modelling. 4. Peer review of the main SKB Project SAFE supporting documentation to evaluate quality, completeness and the implications of the results. 5. An independent PA exercise, using the AMBER code. 6. A review of an English translation of Section 5 of SKB's Project SAFE Final Safety Report. The present report covers only items 3 to 6, and a separate report provides a more detailed description of item 5. As a result of this review, the key issues that the regulatory authorities will need to address when reviewing SKB's safety case for SFR 1 have been identified as: 1. There is no clear statement of SKB's overall safety concept for SFR 1. It is therefore difficult to judge the results of the PA against

Development of the KBS-3 method. Survey of SKB's research programs and safety assessments, reviews by Government authorities and SKB's international research cooperation; Utvecklingen av KBS-3-metoden. Genomgaang av forskningsprogram, saekerhetsanalyser, myndighetsgranskningar samt SKB:s internationella forskningssamarbete

Energy Technology Data Exchange (ETDEWEB)

2010-11-15

The purpose of this report is to outline the origin and development over the past 30 years (up to 2009) of the KBS-3 method proposed by the Swedish Nuclear Fuel and Waste Management Co (SKB) for final disposal of spent nuclear fuel. The KBS-3 method is based on three protective barriers. The spent nuclear fuel is encapsulated in impermeable copper canisters. The canisters are placed in crystalline basement rock at a depth of 400-700 metres, embedded in bentonite clay. After disposal the tunnels and rock caverns are sealed. The account does not claim to cover all parts of the extensive technical and scientific research and development work conducted by SKB in form of collecting data, refining methods and increasing process understanding. The report forms part of the background material which SKB has gathered as a basis for future applications regarding permits under the Environmental Code and the Nuclear Activities Act to build and operate facilities for encapsulation and final disposal of spent nuclear fuel. A prominent feature of the industrial development work on the final disposal of spent nuclear fuel has been an openness for a constant input of ideas and opinions from society and public bodies (the Government, national authorities, universities and other institutes of higher education, municipalities and various non-governmental organizations). The presentation sheds light on developments in a number of areas that are of central importance for safety in a KBS-3 repository. In SKB's RDandD Programme 2007, these areas go under the headings rock line, buffer line, canister line, backfilling line and closure line. Furthermore, attention has been given to issues related to the possible retrieval of deposited canisters, variants of KBS-3, deposition technology and safety assessment, as well as a number of interdisciplinary issues. The development of methods for the safety assessment has been an important part of the development of the KBS-3 method. The work

The Swedish Nuclear Power Inspectorate's evaluation of SKB's RD and D Program 98. Review report

International Nuclear Information System (INIS)

1999-04-01

According to the Act (1984:3) on Nuclear Activities, the full responsibility for the safe management and final disposal of spent nuclear fuel and nuclear waste rests with the owners of the Swedish nuclear power reactors. In accordance with the Act (1992:1537) on the Financing of Future Expenses for Spent Nuclear Fuel etc., the owners are also responsible for ensuring that funds are set aside to cover the future expenses of the management and final disposal of spent nuclear fuel and nuclear waste. Furthermore, nuclear reactor owners must conduct, and every three years, submit a research and development programme for the management of the spent nuclear fuel and nuclear waste. The programme must also cover the measures which are necessary for the decommissioning and dismantling of the nuclear installations. SKI must submit the programme documents to the Government, along with its own statement. The owners of the nuclear power reactors have formed a joint company, SKB which, on behalf of the owners, fulfils the owners' statutory obligations with respect to the management and final disposal of spent nuclear fuel and nuclear waste and conducts related research and development. The programme now submitted by SKB is the latest in the series which started with RandD Programme 86. The current programme was submitted in September 1998 and is called RDandD Programme 98 (programme for Research, Development and Demonstration). In RDandD Programme 98, SKB has stated that it particularly welcomes viewpoints concerning: Whether deep disposal according to the KBS-3 method will continue to be the preferred method. The body of material that SKB is compiling in preparation for the selection of sites for site investigation. What is to be included in future Environmental Impact Statements (EIS). Compared to previous programmes, RDandD Programme 98 is focused to a greater extent on method and site selection and on issues relating to the decision-making process. In order to emphasise that

SKI review of SKB research programs 1992. Compilation of scientific reports

International Nuclear Information System (INIS)

1993-03-01

Swedish Nuclear Power Inspectorate (SKI) has reviewed the research programs 1992 of the Swedish Nuclear Fuel and Waste Management Co (SKB). This report presents the examination of the individual programs

The role of international cooperation regarding safety assessment development in the SKB research program

International Nuclear Information System (INIS)

Eng, T.; Ahlstrom, P.

1989-01-01

Cooperation and exchange of information with organizations in foreign countries regarding nuclear waste management constitutes an important part of the overall research and development activities of SKB. In the safety assessment of a repository for spent nuclear fuel natural phenomena have to be described with different kinds of models based on both general and site specific data. The international cooperation efforts to achieve models and methods for this type of descriptions, and where SKB are largely part, is summarized in this paper

Comparison of the SKI, SKB, and SKN geological and structural models of the Aespoe area

International Nuclear Information System (INIS)

Tiren, S.A.

1996-06-01

Three sets of geological and structural models produced by three different groups are compared. The same set of basic data has been available to each of the groups. The models, all of which are 2 by 2 km by 1 km deep - or smaller, are based entirely on surface-based investigations. The modelled area is centered on the island of Aespoe, where SKB has built the Hard Rock Laboratory (HRL) in plutonic bedrock at a depth of 500 m. SKB (Swedish Nuclear Fuel and Waste Management Co) has recorded the basic data during the period 1986 to 1991, before starting the underground work. One of the main tasks in the SKB characterization of the HRL rock mass was to predict which of the geological structures will have the greatest rock-mechanical and hydraulic significance. The National Board for Spent Nuclear Fuel (SKN) constructed alternative models in 1992 to verify the SKB model. However, the SKN models were subsequently modified and converted into a hydrogeological model. The Swedish Nuclear Inspectorate (SKI) chose Aespoe as a hypothetical site for storage of nuclear waste in their SITE 94 project. The objective of the project is to assist SKI in their future review of SKB's application for a license to dispose of spent nuclear fuel underground. The agreement of the three models is found to be best where the density of information is greatest. The main difference between the two geological models is related to the inferred effects of block faulting on the rock type distribution. The correlation of moderately to gently inclined zones between the models is relatively poor at depth

Comparison of the SKI, SKB, and SKN geological and structural models of the Aespoe area

Energy Technology Data Exchange (ETDEWEB)

Tiren, S.A. [Geosigma AB, Uppsala (Sweden)

1996-06-01

Three sets of geological and structural models produced by three different groups are compared. The same set of basic data has been available to each of the groups. The models, all of which are 2 by 2 km by 1 km deep - or smaller, are based entirely on surface-based investigations. The modelled area is centered on the island of Aespoe, where SKB has built the Hard Rock Laboratory (HRL) in plutonic bedrock at a depth of 500 m. SKB (Swedish Nuclear Fuel and Waste Management Co) has recorded the basic data during the period 1986 to 1991, before starting the underground work. One of the main tasks in the SKB characterization of the HRL rock mass was to predict which of the geological structures will have the greatest rock-mechanical and hydraulic significance. The National Board for Spent Nuclear Fuel (SKN) constructed alternative models in 1992 to verify the SKB model. However, the SKN models were subsequently modified and converted into a hydrogeological model. The Swedish Nuclear Inspectorate (SKI) chose Aespoe as a hypothetical site for storage of nuclear waste in their SITE 94 project. The objective of the project is to assist SKI in their future review of SKB`s application for a license to dispose of spent nuclear fuel underground. The agreement of the three models is found to be best where the density of information is greatest. The main difference between the two geological models is related to the inferred effects of block faulting on the rock type distribution. The correlation of moderately to gently inclined zones between the models is relatively poor at depth. 46 refs, 30 figs, 18 tabs.

Long-term development of the super-regional area of Olkiluoto/Forsmark/Laxemar. Minutes from the Posiva and SKB workshop

Energy Technology Data Exchange (ETDEWEB)

Lindborg, Tobias; Rubio Lind, Lotta (eds.)

2006-12-15

The siting program for a repository of spent fuel currently collects large data sets from the surface ecosystem, as well from the geosphere. For Sweden, the program for the surface ecosystem is described in the reports SKB-R--00-19 and SKB-R--03-06, and the general siting program in SKB-TR--01-29. Correspondingly, for Finland the Posiva programme is described in POSIVA--03-02, POSIVA--03-05 and POSIVA--05-03. The collected data is used in different kinds of modelling, mainly for the safety assessment for the repository and for environmental impact assessment (EIA). Since, Posiva and SKB (the nuclear waste management companies of Finland and Sweden, resp.) are sharing the same super regional area in terms of historical and future development, it is of great importance to coordinate the descriptions of this area and its properties to avoid discrepancies and to make better use of the data collected at both sites/countries. In order to accomplish this collaboration, a consensus was attained on which properties/parameters/variables that were important to consider and it was decided which references, models and equations to be use in the site descriptions. Furthermore, possible gaps in the understanding of the site were identified and discussed. A plan on how to handle these gaps was made, i.e. do we need to initiate more research? Participants from the site investigation program, the analysis group, safety assessment and research from Posiva and SKB were invited to the workshop. Besides the major aim of the workshop, other important objectives were to enhance the communication between Posiva and SKB, increase the awareness of different issues handled at the sites/subject area, and to build a better understanding for the models. Additional it should be mentioned that this is only a record of initial discussions and there might be changes in the practical implementation due to e.g. change of focus with advances in the programmes. The workshop and this report of the

Long-term development of the super-regional area of Olkiluoto/Forsmark/Laxemar. Minutes from the Posiva and SKB workshop

International Nuclear Information System (INIS)

Lindborg, Tobias; Rubio Lind, Lotta

2006-12-01

The siting program for a repository of spent fuel currently collects large data sets from the surface ecosystem, as well from the geosphere. For Sweden, the program for the surface ecosystem is described in the reports SKB-R--00-19 and SKB-R--03-06, and the general siting program in SKB-TR--01-29. Correspondingly, for Finland the Posiva programme is described in POSIVA--03-02, POSIVA--03-05 and POSIVA--05-03. The collected data is used in different kinds of modelling, mainly for the safety assessment for the repository and for environmental impact assessment (EIA). Since, Posiva and SKB (the nuclear waste management companies of Finland and Sweden, resp.) are sharing the same super regional area in terms of historical and future development, it is of great importance to coordinate the descriptions of this area and its properties to avoid discrepancies and to make better use of the data collected at both sites/countries. In order to accomplish this collaboration, a consensus was attained on which properties/parameters/variables that were important to consider and it was decided which references, models and equations to be use in the site descriptions. Furthermore, possible gaps in the understanding of the site were identified and discussed. A plan on how to handle these gaps was made, i.e. do we need to initiate more research? Participants from the site investigation program, the analysis group, safety assessment and research from Posiva and SKB were invited to the workshop. Besides the major aim of the workshop, other important objectives were to enhance the communication between Posiva and SKB, increase the awareness of different issues handled at the sites/subject area, and to build a better understanding for the models. Additional it should be mentioned that this is only a record of initial discussions and there might be changes in the practical implementation due to e.g. change of focus with advances in the programmes. The workshop and this report of the

Interface currents in topological superconductor–ferromagnet heterostructures

International Nuclear Information System (INIS)

Brydon, P M R; Timm, Carsten; Schnyder, Andreas P

2013-01-01

We propose the existence of a substantial charge current parallel to the interface between a noncentrosymmetric superconductor and a metallic ferromagnet. Our analysis focuses upon two complementary orbital-angular-momentum pairing states of the superconductor, exemplifying topologically nontrivial states which are gapped and gapless in the bulk, respectively. Utilizing a quasiclassical scattering theory, we derive an expression for the interface current in terms of Andreev reflection coefficients. Performing a systematic study of the current, we find stark qualitative differences between the gapped and gapless superconductors, which reflect the very different underlying topological properties. For the fully gapped superconductor, there is a sharp drop in the zero-temperature current as the system is tuned from a topologically nontrivial to a trivial phase. We explain this in terms of the sudden disappearance of the contribution to the current from the subgap edge states at the topological transition. The current in the gapless superconductor is characterized by a dramatic enhancement at low temperatures, and exhibits a singular dependence on the exchange-field strength in the ferromagnetic metal at zero temperature. This is caused by the energy shift of the strongly spin-polarized nondegenerate zero-energy flat bands due to their coupling to the exchange field. We argue that the interface current provides a novel test of the topology of the superconductor, and discuss prospects for the experimental verification of our predictions. (paper)

Conversion of spin current into charge current in a topological insulator: Role of the interface

Science.gov (United States)

Dey, Rik; Prasad, Nitin; Register, Leonard F.; Banerjee, Sanjay K.

2018-05-01

Three-dimensional spin current density injected onto the surface of a topological insulator (TI) produces a two-dimensional charge current density on the surface of the TI, which is the so-called inverse Edelstein effect (IEE). The ratio of the surface charge current density on the TI to the spin current density injected across the interface defined as the IEE length was shown to be exactly equal to the mean free path in the TI determined to be independent of the electron transmission rate across the interface [Phys. Rev. B 94, 184423 (2016), 10.1103/PhysRevB.94.184423]. However, we find that the transmission rate across the interface gives a nonzero contribution to the transport relaxation rate in the TI as well as to the effective IEE relaxation rate (over and above any surface hybridization effects), and the IEE length is always less than the original mean free path in the TI without the interface. We show that both the IEE relaxation time and the transport relaxation time in the TI are modified by the interface transmission time. The correction becomes significant when the transmission time across the interface becomes comparable to or less than the original momentum scattering time in the TI. This correction is similar to experimental results in Rashba electron systems in which the IEE relaxation time was found shorter in the case of direct interface with metal in which the interface transmission rate will be much higher, compared to interfaces incorporating insulating oxides. Our results indicate the continued importance of the interface to obtain a better spin-to-charge current conversion and a limitation to the conversion efficiency due to the quality of the interface.

Review of SKB's Safety Assessment SR-Can: Contributions in Support of SKI's and SSI's Review by External Consultants

International Nuclear Information System (INIS)

2008-03-01

The Swedish Nuclear Fuel and Waste Management Co (SKB) plans to submit a license application for the construction of a repository for spent nuclear fuel in Sweden 2010. In support of this application SKB will present a safety report, SR-Site, on the repository's long-term safety and radiological consequences. As a preparation for SR-Site, SKB published the preliminary safety assessment SR-Can in November 2006. The purposes were to document a first evaluation of long-term safety for the two candidate sites at Forsmark and Laxemar and to provide feedback to SKB's future programme of work. An important objective of the authorities' review of SR-Can is to provide guidance to SKB on the complete safety reporting for the license application. The authorities have engaged external experts for independent modelling, analysis and review, with the aim to provide a range of expert opinions related to the sufficiency and appropriateness of various aspects of SR-Can. The conclusions and judgments in this report are those of the authors and may not necessarily coincide with those of SKI and SSI. The authorities own review will be published separately (SKI Report 2008:23, SSI Report 2008:04 E). This report compiles contributions from several specific research projects. The separate reviews cover topics regarding the engineered barrier system, the quality assurance, the climate evolution and its effects, and the ecosystems and environmental impacts. All contributions are in English apart from the review concerning ecosystems and environmental impacts, which is presented in Swedish

The Swedish Nuclear Power Inspectorate's evaluation of SKB's RD and D Program 98. Review report

Energy Technology Data Exchange (ETDEWEB)

NONE

1999-04-01

According to the Act (1984:3) on Nuclear Activities, the full responsibility for the safe management and final disposal of spent nuclear fuel and nuclear waste rests with the owners of the Swedish nuclear power reactors. In accordance with the Act (1992:1537) on the Financing of Future Expenses for Spent Nuclear Fuel etc., the owners are also responsible for ensuring that funds are set aside to cover the future expenses of the management and final disposal of spent nuclear fuel and nuclear waste. Furthermore, nuclear reactor owners must conduct, and every three years, submit a research and development programme for the management of the spent nuclear fuel and nuclear waste. The programme must also cover the measures which are necessary for the decommissioning and dismantling of the nuclear installations. SKI must submit the programme documents to the Government, along with its own statement. The owners of the nuclear power reactors have formed a joint company, SKB which, on behalf of the owners, fulfils the owners' statutory obligations with respect to the management and final disposal of spent nuclear fuel and nuclear waste and conducts related research and development. The programme now submitted by SKB is the latest in the series which started with RandD Programme 86. The current programme was submitted in September 1998 and is called RDandD Programme 98 (programme for Research, Development and Demonstration). In RDandD Programme 98, SKB has stated that it particularly welcomes viewpoints concerning: Whether deep disposal according to the KBS-3 method will continue to be the preferred method. The body of material that SKB is compiling in preparation for the selection of sites for site investigation. What is to be included in future Environmental Impact Statements (EIS). Compared to previous programmes, RDandD Programme 98 is focused to a greater extent on method and site selection and on issues relating to the decision-making process. In order to emphasise

Tracer tests - possibilities and limitations. Experience from SKB fieldwork: 1977-2007

Energy Technology Data Exchange (ETDEWEB)

Loefgren, Martin; Crawford, James; Elert, Mark (Kemakta Konsult AB, Stockholm (SE))

2007-09-15

only for the tracer test configuration, but not separate them without introducing additional assumptions. Field scale tracer tests (in flowing fractures) alone cannot deliver individual transport parameters, such as effective diffusivity, flow-wetted surface, etc in the absence of additional supporting information. Lumped or individual transport parameters obtained from inverse modelling of tracer test data are not directly transferable to Safety Assessment flow conditions or timescales. In addition to the above findings, another objective of this report has been to describe and highlight a number of elaborate in situ tracer tests that SKB has performed and reported. Many of these experiments have contributed immeasurably to current process understanding although may not be widely known to the general reader

SKB studies of the periglacial environment - report from field studies in Kangerlussuaq, Greenland 2008 and 2010

International Nuclear Information System (INIS)

Clarhaell, Anders

2011-03-01

In order to reduce uncertainties in safety assessments of the planned repository of spent nuclear fuel, SKB identified the need to increase the understanding of glacial and periglacial environments. In collaboration with Posiva OY (Finland) and NWMO (Canada), SKB started the Greenland Analogue Project (GAP) in order to study the effect of climate cooling and glaciation on repository safety. GAP chose an area northeast of Kangerlussuaq, West Greenland, to be studied as a present-day analogue of a future glacial environment in both Scandinavia and Canada. The GAP, planned to run from 2009 until 2012, conducts in situ investigations of some of the parameters and processes needed to achieve a realistic understanding of how an ice sheet may impact a deep repository. In addition, the GAP will provide measurements, observations and data that may significantly improve safety assessments and risk analyses of glaciation scenarios /SKB 2011/. Issues regarding the periglacial surface environment are not included in GAP's primary focus, which has led SKB to initiate parallel activities in the same area. This new project is named The Greenland Analogue Surface Project (GRASP), and will conduct conceptual and numerical modelling of ecosystems, hydrology and near surface hydrogeology. Choosing the same investigation area for the two projects will facilitate common usage of base-line data and logistics in the field. Information from the GRASP will be applied for a better understanding of ecological and hydrological processes in a future periglacial environment in Forsmark. Annual and long-term dynamics of the permafrost are of special interest, as well as the impact of taliks on the transport of matter from the bedrock up towards the surface. This report primarily describes findings from the field season of 2010, but does also report on field work conducted by SKB in 2008. The report provides some background information on the area, describes preliminary results and set-up for

SKB studies of the periglacial environment - report from field studies in Kangerlussuaq, Greenland 2008 and 2010

Energy Technology Data Exchange (ETDEWEB)

Clarhaell, Anders

2011-03-15

In order to reduce uncertainties in safety assessments of the planned repository of spent nuclear fuel, SKB identified the need to increase the understanding of glacial and periglacial environments. In collaboration with Posiva OY (Finland) and NWMO (Canada), SKB started the Greenland Analogue Project (GAP) in order to study the effect of climate cooling and glaciation on repository safety. GAP chose an area northeast of Kangerlussuaq, West Greenland, to be studied as a present-day analogue of a future glacial environment in both Scandinavia and Canada. The GAP, planned to run from 2009 until 2012, conducts in situ investigations of some of the parameters and processes needed to achieve a realistic understanding of how an ice sheet may impact a deep repository. In addition, the GAP will provide measurements, observations and data that may significantly improve safety assessments and risk analyses of glaciation scenarios /SKB 2011/. Issues regarding the periglacial surface environment are not included in GAP's primary focus, which has led SKB to initiate parallel activities in the same area. This new project is named The Greenland Analogue Surface Project (GRASP), and will conduct conceptual and numerical modelling of ecosystems, hydrology and near surface hydrogeology. Choosing the same investigation area for the two projects will facilitate common usage of base-line data and logistics in the field. Information from the GRASP will be applied for a better understanding of ecological and hydrological processes in a future periglacial environment in Forsmark. Annual and long-term dynamics of the permafrost are of special interest, as well as the impact of taliks on the transport of matter from the bedrock up towards the surface. This report primarily describes findings from the field season of 2010, but does also report on field work conducted by SKB in 2008. The report provides some background information on the area, describes preliminary results and set-up for

Opinions on SKB's Safety Assessments SR 97 and SFL 3-5. A Review by SKI Consultants

Energy Technology Data Exchange (ETDEWEB)

NONE

2000-12-01

The Swedish Nuclear Fuel and Waste Management Co. (SKB) has presented their safety assessment 'Deep repository for spent nuclear fuel, SR 97 - Post-closure safety'. SKB's report is part of the documentation that has been required by the Government before the start of site investigations. The Swedish Nuclear Power Inspectorate (SKI) is reviewing SR 97 according to earlier Government decisions. In its review work SKI has asked several consultants, that recently have been performing research work for SKI, to give their opinions on SR 97. SKI and the Swedish Radiation Protection Institute (SSI) have used these reports from the consultants as one complementary basis for the formulation of the SKI/SSI review report. This is a compilation of the reports from the different consultants, and therefore the different contributions vary in length, style and language. Included are also two consultant reports, giving comments on SKB's preliminary safety assessment for SFL 3-5 (deep repository for long-lived low- and intermediate-level waste). The 17 contributions have all been separately indexed.

Opinions on SKB's Safety Assessments SR 97 and SFL 3-5. A Review by SKI Consultants

International Nuclear Information System (INIS)

2000-12-01

The Swedish Nuclear Fuel and Waste Management Co. (SKB) has presented their safety assessment 'Deep repository for spent nuclear fuel, SR 97 - Post-closure safety'. SKB's report is part of the documentation that has been required by the Government before the start of site investigations. The Swedish Nuclear Power Inspectorate (SKI) is reviewing SR 97 according to earlier Government decisions. In its review work SKI has asked several consultants, that recently have been performing research work for SKI, to give their opinions on SR 97. SKI and the Swedish Radiation Protection Institute (SSI) have used these reports from the consultants as one complementary basis for the formulation of the SKI/SSI review report. This is a compilation of the reports from the different consultants, and therefore the different contributions vary in length, style and language. Included are also two consultant reports, giving comments on SKB's preliminary safety assessment for SFL 3-5 (deep repository for long-lived low- and intermediate-level waste). The 17 contributions have all been separately indexed

Review of SKB's reporting of SR 97

International Nuclear Information System (INIS)

Tiren, S.A.

2000-01-01

The task of the safety assessment is to show 'that the repository has been designed with sufficient margins to be safe in spite of the incomplete knowledge available'. SKB mentions 'confidence in the results' as an important aspect. For the layman, confidence in the information presented is of the greatest importance. This means that the presentation of the safety assessment should be of a high visual standard with respect to descriptions of processes and events. SKB presented the purpose of SR 97 as four points. From a geological-structural geological viewpoint, the following can be mentioned: 1. Methodology for evaluating the geometry of the structural patterns of the bedrock at a depth of 500 m exists in general, but there are also certain deficiencies. Examples include determining the position of the individual structures and obtaining information. The importance of the bedrock is not completely clear. What is related to the rock type and what is related to the geological environment (including the geological evolution)? A clearer and more systematic compilation of data used in the safety assessment is required. 2. Work involving alternative models and evaluations of how well the models explain the collected data would be appropriate. The geological and structural models for a site are included as the base data in calculations and other modelling conducted in connection with the characterization of a site. 3. SR 97 does not provide any detailed information on site investigations. 4. The function of the bedrock as an external barrier is shown. However, to a certain extent, information on how this barrier can be affected by aseismic creep movements along fracture structures and the impact of selective erosion along such structures is lacking. Furthermore, criteria for properties of the rock volumes where deposition drifts are planned should be expanded, such as by determining a minimum width and suitable length-width relations

Description of hydrogeological data in SKB's database GEOTAB

International Nuclear Information System (INIS)

Gentzschein, B.

1986-12-01

Since 1977 Swedish Nuclear Fuel and Waste Management Co., SKB has been performing a research and development programme for final disposal and spent nuclear fuel. The purpose of the programme is to acquire knowledge and data of radioactive waste. Measurement for the characterisation of geological, geophysical, hydrogeological and hydrochemical conditions are performed in specific site investigations as well as for geoscientific projects. A database, called GEOTAB, was investigated. It is based on a concept from Mimer Information System, and have been further developed by Ergo-Data. The hardware is a VAX 750 computer located at KRAB (Kraftverksbolagens Redovisningsavdelning AB) in Stockholm. (orig./DG)

SSI and SKI's Review of SKB's Updated Final Safety Report for SFR 1. Review Report

International Nuclear Information System (INIS)

2003-10-01

The Repository for Radioactive Operational Waste (SFR 1) is now the object of a new review by the Swedish Radiation Protection Authority (SSI) and the Swedish Nuclear Power Inspectorate (SKI). One of the stipulations for operating SFR 1 was that a new assessment of the long-term performance and environmental consequences of the repository should be conducted once every 10 years by the licensee, the Swedish Nuclear Fuel and Waste Management Co (SKB). During the time that SFR 1 has been in operation, experience has been gained of operating the facility and new knowledge of long-term performance of SFR 1 has been obtained. New regulations for nuclear facilities have been promulgated since SFR 1 was taken into operation (1988). A review committee comprising employees from SKI and SSI has conducted the review of SSR 2001. This review report has resulted in the committee's evaluation of the safety of SFR 1 and is the basis of the regulatory authorities' decision concerning any amendments to the stipulations for the operation of SFR 1. However, the review has found deficiencies in the follow up of the development of design basis norms since the facility was constructed as well as deficiencies in learning from operating experience. However, the overall evaluation is that the facility is being operated in an acceptable manner from the standpoint of safety. With respect to the long-term performance of the repository, it is a deficiency that SSR 2001 does not describe how compliance with the stipulated radiation protection requirements on optimisation and use of the best available technology (BAT) is achieved during operation. In the opinion of the review committee, issues relating to occupational radiation protection are being handled satisfactorily and the operational releases of radioactive substances are very small. Safety and Radiation Protection after Closure SKB's long-term repository performance assessment contains essential updates and improvements compared with the

SKB`s planning of the EIA in connection with the final disposal of nuclear waste

Energy Technology Data Exchange (ETDEWEB)

Thegerstroem, C.; Forsstroem, H. [Swedish Nuclear Fuel and Waste Management Co., Stockholm (Sweden)

1995-12-01

The plans for the final disposal of Swedish nuclear waste are summarized. The legal requirements on Environmental Impact Statements (EIS) and their role in the program for the final disposal of nuclear waste are described. SKB`s view of the purpose of the Environmental Impact Assessment is described in the light of the experience which now exists from the work on an encapsulation facility and a deep repository. In order to obtain an adequate basis for decision-making, the EIS is of central importance. In SKB`s view, with regard to the final disposal of nuclear waste in Sweden, there is a very good possibility of fulfilling the requirements on the EIS which should be made within modern environmental protection work. 8 refs, 5 figs.

Alternative modelling of brittle structures in a sub-area of the SKB candidate area at Forsmark, eastern Sweden.

Energy Technology Data Exchange (ETDEWEB)

Askling, Per; Tiren, Sven A.; Beckholmen, Monica; Straeng, Thomas (Geosigma AB, Uppsala (Sweden))

2008-11-15

One way to test the confidence of a presented model is to construct an alternative model. Such work is cognitive process of skill acquisition and also a process of understanding data in the sense of sorting and classifying data. This is of particular interest for the Swedish Radiation Safety Authority (SSM) in their technical review of SKB's on-going site investigation programme for potential repository sites. In this study, an alternative brittle deformation model of a selected part of the SKB candidate area in eastern Sweden was constructed. The input data set was obtained from SKB's database SICADA and is a selected set of data from five cored boreholes drilled from two drill-sites and comprises geophysical borehole logs, geological core-logs, hydrological logs (PFL; Posiva Flow Log) and borehole deviation measurements. Statistical cluster analysis applied on the geophysical borehole data were used to obtain the locations of bedrock with contrasting physical characteristics similar to those of brittle deformation zones. The cluster analysis is an objective procedure, contrasting with SKB's more subjective approach to the single-hole interpretation. Thus some differences are expected which could illustrate the effect of methodology that includes subjective 'expert judgement.' and indicate the possibility of alternative interpretations. The information about brittle structures in the geological boreholes logs was sorted and classification was made according to character of the structures (all fractures, open fractures, partly open fractures, frequency, orientate on/identification of fracture sets, sections of crush rock, and alteration). A separate study was performed to relate rock alteration with structures. The resolution applied in the fracture statistics is one metre, i.e. all studied entities were expressed per metre borehole length. All clusters were structurally characterized by the fractures inside the clusters (orientation and

Alternative modelling of brittle structures in a sub-area of the SKB candidate area at Forsmark, eastern Sweden

International Nuclear Information System (INIS)

Askling, Per; Tiren, Sven A.; Beckholmen, Monica; Straeng, Thomas

2008-11-01

One way to test the confidence of a presented model is to construct an alternative model. Such work is cognitive process of skill acquisition and also a process of understanding data in the sense of sorting and classifying data. This is of particular interest for the Swedish Radiation Safety Authority (SSM) in their technical review of SKB's on-going site investigation programme for potential repository sites. In this study, an alternative brittle deformation model of a selected part of the SKB candidate area in eastern Sweden was constructed. The input data set was obtained from SKB's database SICADA and is a selected set of data from five cored boreholes drilled from two drill-sites and comprises geophysical borehole logs, geological core-logs, hydrological logs (PFL; Posiva Flow Log) and borehole deviation measurements. Statistical cluster analysis applied on the geophysical borehole data were used to obtain the locations of bedrock with contrasting physical characteristics similar to those of brittle deformation zones. The cluster analysis is an objective procedure, contrasting with SKB's more subjective approach to the single-hole interpretation. Thus some differences are expected which could illustrate the effect of methodology that includes subjective 'expert judgement.' and indicate the possibility of alternative interpretations. The information about brittle structures in the geological boreholes logs was sorted and classification was made according to character of the structures (all fractures, open fractures, partly open fractures, frequency, orientate on/identification of fracture sets, sections of crush rock, and alteration). A separate study was performed to relate rock alteration with structures. The resolution applied in the fracture statistics is one metre, i.e. all studied entities were expressed per metre borehole length. All clusters were structurally characterized by the fractures inside the clusters (orientation and density of fractures) and

Opinions on SKB's Safety Assessments SR 97 and SFL 3-5. A Review by SKI Consultants

Energy Technology Data Exchange (ETDEWEB)

NONE

2000-12-01

The Swedish Nuclear Fuel and Waste Management Co. (SKB) has presented their safety assessment 'Deep repository for spent nuclear fuel, SR 97 - Post-closure safety'. SKB's report is part of the documentation that has been required by the Government before the start of site investigations. The Swedish Nuclear Power Inspectorate (SKI) is reviewing SR 97 according to earlier Government decisions. In its review work SKI has asked several consultants, that recently have been performing research work for SKI, to give their opinions on SR 97. SKI and the Swedish Radiation Protection Institute (SSI) have used these reports from the consultants as one complementary basis for the formulation of the SKI/SSI review report. This is a compilation of the reports from the different consultants, and therefore the different contributions vary in length, style and language. Included are also two consultant reports, giving comments on SKB's preliminary safety assessment for SFL 3-5 (deep repository for long-lived low- and intermediate-level waste). The 17 contributions have all been separately indexed.

Nuclear waste - research and technique development. KASAMS's Review of the Swedish Nuclear Fuel and Waste Management Co's (SKB's) RD and D Programme 2001

International Nuclear Information System (INIS)

2002-01-01

This report is KASAM's review statement to the Government on the Swedish Nuclear Fuel and Waste Management Co's (SKB's) RD and D Programme 2001. KASAM's review was primarily conducted through work by KASAM's members, special adviser, experts and secretary. In KASAM's opinion, the reactor owners, through RD and D Programme 2001, have complied with the requirements of paragraph 12 of the Act on Nuclear Activities. In KASAM's opinion, SKB's research and development programme shows great merit. This applies to both what SKB has done and what it intends to do. The report is well-structured and clear. RD and D Programme 2001 shows that there is still a considerable need for development work in a number of important technical areas. This applies, for example, to the fabrication and sealing of canisters as well as control methods for these activities. Within other areas, for example, geology, chemistry, hydrology, biology and rock mechanics, there is also a great need for further research and development work, and for practical demonstrations of technical applications. In KASAM's opinion, humanities and social science issues, that are of importance for the disposal of nuclear waste, should be accorded greater attention. In Chapter 14, KASAM has presented a proposal for how research in these areas can be organised and financed. KASAM emphasizes that future RD and D programmes should have a broad scientific basis in order to comply with the requirements of the Act on Nuclear Activities regarding comprehensiveness. In their review statements on RD and D Programme 2001, the Swedish Nuclear Power Inspectorate (SKI) and the Swedish Radiation Protection Authority (SSI) have proposed that SKB should be required to present a strategy document which should be kept updated. In KASAM's opinion, such a report of current strategic issues should be made available to the public and other parties concerned. KASAM also believes that such a documentation of strategy issues should be

Description of background data in the SKB database GEOTAB. Version 2

International Nuclear Information System (INIS)

Eriksson, E.; Sehlstedt, S.

1991-03-01

During the research and development program performed by SKB for the final disposal of spent nuclear fuel, a large quantity of geoscientific data was collected. Most of this data was stored in a database called Geotab. The data is organized into eight groups as follows: Background information; Geological data; Borehole geophysical measurements; Ground surface geophysical measurements; Hydrogeological and meteorological data; Hydrochemical data; Petrophysical measurements and Tracer tests. Except for the case of borehole geophysical data, ground surface geophysical data and petrophysical data, described in the same report, the data in each group is described in a separate SKB report. The present report describes data within the Background data group. This data provides information on the location of areas studied, borehole positions and also some drilling information. Data is normally collected on forms or as notes and this is then stored into the database. The background data group, called BACKGROUND, is divided into several subgroups: BGAREA area background data; BGDRILL drilling information; BGDRILLP drill penetration data; BGHOLE borehole information; BGTABLES number of rows in a table and BGTOLR data table tolerance. A method consist of one or several data tables. In each chapter a method and its data tables are described. (authors)

Geochemical Parameters Required from the SKB Site Characterisation Programme

International Nuclear Information System (INIS)

Bath, Adrian

2002-01-01

SKB has described its approach to site characterisation in a number of Technical Reports. One of the scientific topics in which specific information requirements and priorities are set out is geochemistry. This report for SKI examines critically whether the geochemical parameters identified in the SKB programme documents will be adequate for safety and regulatory requirements. It also examines some of the details of parameter requirements and interpretation tools that will be necessary to convert site investigation data into knowledge about chemical conditions and groundwater movements. The SKB strategy for geochemical data focuses on a small number of 'suitability indicators', primarily dissolved oxygen, pH and salinity. Their parameter requirements aim to assess those primary characteristics, as well as to acquire a wider range of data that will support those assessments and provide a broader understanding of candidate areas. An initial observation in this review that, though it is a primary suitability indicator, dissolved oxygen apparently will not be measured and instead will be inferred from other redox indicators. This raises a number of issues about sampling and monitoring measures, analytical data reliability and sensitivity, and the degree of confidence in geochemical understanding. A geochemical programme involves reconnaissance by desk study and acquisition of new data at levels of details that are appropriate to the stage of site investigations. As early as possible, a conceptual model of a candidate area should help to define the objectives of geochemical measurements on both rock and groundwater samples. It is recommended that parameters requirements should be defined and considered not only in terms of isolated measurements but more in terms of addressing broader objectives that relate to safety and also to geoscientific understanding. The safety priorities remain (e.g. dissolved oxygen) but will then be supported by an understanding of processes

Geochemical Parameters Required from the SKB Site Characterisation Programme

Energy Technology Data Exchange (ETDEWEB)

Bath, Adrian [Intellisci Ltd., Loughborough (United Kingdom)

2002-01-01

SKB has described its approach to site characterisation in a number of Technical Reports. One of the scientific topics in which specific information requirements and priorities are set out is geochemistry. This report for SKI examines critically whether the geochemical parameters identified in the SKB programme documents will be adequate for safety and regulatory requirements. It also examines some of the details of parameter requirements and interpretation tools that will be necessary to convert site investigation data into knowledge about chemical conditions and groundwater movements. The SKB strategy for geochemical data focuses on a small number of 'suitability indicators', primarily dissolved oxygen, pH and salinity. Their parameter requirements aim to assess those primary characteristics, as well as to acquire a wider range of data that will support those assessments and provide a broader understanding of candidate areas. An initial observation in this review that, though it is a primary suitability indicator, dissolved oxygen apparently will not be measured and instead will be inferred from other redox indicators. This raises a number of issues about sampling and monitoring measures, analytical data reliability and sensitivity, and the degree of confidence in geochemical understanding. A geochemical programme involves reconnaissance by desk study and acquisition of new data at levels of details that are appropriate to the stage of site investigations. As early as possible, a conceptual model of a candidate area should help to define the objectives of geochemical measurements on both rock and groundwater samples. It is recommended that parameters requirements should be defined and considered not only in terms of isolated measurements but more in terms of addressing broader objectives that relate to safety and also to geoscientific understanding. The safety priorities remain (e.g. dissolved oxygen) but will then be supported by an understanding of

Final Disposal of Nuclear Waste. The Swedish National Council for Nuclear Waste's Review of the Swedish Nuclear Fuel and Waste Management Co's (SKB's) RDandD Programme 2007

International Nuclear Information System (INIS)

2009-01-01

The Swedish National Council for Nuclear Waste finds that the RDandD programme 2007 fulfils the requirements set forth in the Nuclear Activities Act. However, the Council has identified a number of questions and deficiencies to which the Council wishes to draw attention. The Council finds that there are many unclear points regarding buffer, backfill and closure at this stage. The most important properties of the buffer material should be specified and limit values should be determined with respect to swelling potential, retention capacity for radionuclides, chemical stability, hydraulic diffusion, resistance to erosion and level of impurities. Mechanical strength and chemical stability must be guaranteed for compacted components in the buffer. Models should be set up for transport of the most important radioactive isotopes through the bentonite. SKB must also be able to show that the buffer and backfill conform to the initial states assumed by the safety assessment. Special research is required on the interfaces between backfill and buffer and between backfill and rock. SKB needs to consider the problems that can arise during the expected climate change, probably already during the construction period. The final design of the closure should be determined by the properties of the rock with respect to e.g. fractures at different depths and salinity. However, this presumes knowledge of what properties different materials - and mixtures of materials - have and how they can interact to best effect. The Swedish National Council for Nuclear Waste considers it imperative that SKB give a clear account of the judgements underlying site selection. The Council is troubled by the fact that successful rock stress measurements performed so far in Forsmark are too few in number and uncertain at planned repository depth. The Council would also like to emphasize the internal role of safety assessment within SKB as a tool for both following up repository safety during construction

Description of hydrogeological data in SKB's database GEOTAB. Version 2

International Nuclear Information System (INIS)

Gerlach, M.

1991-12-01

During the research and development program performed by SKB for the final disposal of spent nuclear fuel, a large quantity of geoscientific data was collected. Most of this data was stored in a database called GEOTAB. The data is organized into eight groups (subjects) as follows: - Background information. - Geological data. - Borehole geophysical measurements. - Ground surface geophysical measurements. - Hydrogeological and meteorological data. - Hydrochemical data. - Petrophysical measurements. - Tracer tests. Except for the case of borehole geophysical data, ground surface geophysical data and petrophysical data, described in the same report, the data in each group is described in a separate SKB report. The present report described data within the hydrogeological data group. The hydrogeological data groups (subject), called HYDRO, is divided into several subgroups (methods). BHEQUIPE: equipments in borehole. CONDINT: electrical conductivity in pumped water. FLOWMETE: flowmeter tests. GRWB: groundwater level registrations in boreholes. HUFZ: hydraulic unit fracture zones. HURM: hydraulic unit rock mass. HYCHEM: hydraulic test during chemical Sampling. INTER: interference tests. METEOR: meteorological and hydrological measurements. PIEZO: piezometric measurements at depths in boreholes. RECTES: recovery tests. ROCKRM: hydraulic unit rock types in the rock mass. SFHEAD: single hole falling head test. SHBUP: single hole build up test. SHSINJ: single hole steady state tests. SHTINJ: single hole transient injection tests. SHTOLD: single hole transient injections tests - old data. A method consists of one or several data tables. In each chapter a method and its data tables are described. (au)

SSI's Review of the RDandD Program 2004 of the Swedish Nuclear Fuel and Waste Management Co; SSI:s granskning av SKB:s Fud-program 2004

Energy Technology Data Exchange (ETDEWEB)

Larsson, Carl-Magnus; Hedberg, Bjoern; Wiebert, Anders [and others

2005-06-01

In this report the Swedish Radiation Protection Authority's (SSI) review of the Swedish Nuclear Fuel and Waste Management Company's (SKB) RDandD programme 2004 is presented. In the review SSI comments, among other things, SKB's plan of action and future direction of SKB's RDandD programme, need for different types of consultations, plans for demonstration of canister deposition and long term experiments, and strategies for dismantling of nuclear facilities.

Surface currents on the plasma-vacuum interface in MHD equilibria

Science.gov (United States)

Hanson, James

2017-10-01

The VMEC non-axisymmetric MHD equilibrium code can compute free-boundary equilibria. Since VMEC assumes that magnetic fields within the plasma form closed and nested flux surfaces, the plasma-vacuum interface is a flux surface, and the total magnetic field there has no normal component. VMEC imposes this condition of zero normal field using the potential formulation of Merkel, and solves a Neumann problem for the magnetic potential in the exterior region. This boundary condition necessarily admits the possibility of a surface current on the interface. While this surface current may be small in MHD equilibrium, it is readily computed in terms of the magnetic potentials in both the interior and exterior regions, evaluated on the surface. If only the external magnetic potential is known (as in VMEC), then the surface current can be computed from the discontinuity of the tangential field across the interface. Examples of the surface current for VMEC equilibria will be shown for a zero-pressure stellarator equilibrium. Field-line following of the vacuum magnetic field shows magnetic islands within the plasma region.

Variability and Uncertainties of Key Hydrochemical Parameters for SKB Sites

Energy Technology Data Exchange (ETDEWEB)

Bath, Adrian [Intellisci Ltd, Willoughby on the Wolds, Loughborough (United Kingdom); Hermansson, Hans-Peter [Studsvik Nuclear AB, Nykoeping (Sweden)

2006-12-15

The work described in this report is a development of SKI's capability for the review and evaluation of data that will constitute part of SKB's case for selection of a suitable site and application to construct a geological repository for spent nuclear fuel. The aim has been to integrate a number of different approaches to interpreting and evaluating hydrochemical data, especially with respect to the parameters that matter most in assessing the suitability of a site and in understanding the geochemistry and groundwater conditions at a site. It has been focused on taking an independent view of overall uncertainties in reported data, taking account of analytical, sampling and other random and systematic sources of error. This evaluation was carried out initially with a compilation and general inspection of data from the Simpevarp, Forsmark and Laxemar sites plus data from older 'historical' boreholes in the Aespoe area. That was followed by a more specific interpretation by means of geochemical calculations which test the robustness of certain parameters, namely pH and redox/Eh. Geochemical model calculations have been carried out with widely available computer software. Data sources and their handling were also considered, especially access to SKB's SICADA database. In preparation for the use of geochemical modelling programs and to establish comparability of model results with those reported by SKB, the underlying thermodynamic databases were compared with each other and with other generally accepted databases. Comparisons of log K data for selected solid phases and solution complexes from the different thermodynamic databases were made. In general, there is a large degree of comparability between the databases, but there are some significant, and in a few cases large, differences. The present situation is however adequate for present purposes. The interpretation of redox equilibria is dependent on identifying the relevant solid phases and

Analysis of SKB MiniCan-Experiment 3

International Nuclear Information System (INIS)

Smart, Nick; Rance, Andy; Reddy, Bharti; Fennell, Paul; Winsley, Robert

2012-11-01

To ensure the safe encapsulation of spent nuclear fuel rods for geological disposal, SKB of Sweden is planning to use a system that consists of an outer copper canister and a cast iron insert (the KBS-3 concept). In 2007 Serco1 completed the set up of five model canister experiments at SKB's Aespoe laboratory and monitoring has continued since. The original aim of the model canister experiments was to examine how corrosion of the cast iron insert inside a copper canister would evolve with time, if water ingress through a small defect in the copper canister were to occur. Serco arranged manufacture and installation of five miniature copper canisters containing cast iron inserts, with 1 mm defects deliberately machined into the copper shell. The experiments use five small-scale model canisters (300 mm long x 150 mm diameter) that simulate the main features of the SKB canister design (hence the project name, 'MiniCan'). The main aim of the work is to examine how corrosion of the cast iron insert will evolve if a leak is present in the outer copper canister The experiments also included electrochemical equipment to monitor the corrosion behaviour of the model canisters in situ. In 2011 one of the experiments, Experiment 3, was removed f analysis. This report presents details of the procedures that were applied and the findings that were obtained from the analysis that was carried out on Experiment 3. To minimise exposure to air and to keep the contents of the experiment wet until the analysis was carried out, Experiment 3 was extracted from its borehole in August 2011 directly into a transfer tank that was filled with deaerated groundwater and placed in a purpose-built, water-filled and deoxygenated transfer flask. The transfer flask was then transported to the UK for dismantling and examination in a purpose-built anoxic glovebox that contained the appropriate lifting and cutting equipment for handling and sectioning the copper canister and the cast iron insert. The

Analysis of SKB MiniCan - Experiment 3

Energy Technology Data Exchange (ETDEWEB)

Smart, Nick; Rance, Andy; Reddy, Bharti; Fennell, Paul [AMEC (UK); Winsley, Robert [NDA (Country unknown/Code not available)

2012-11-15

To ensure the safe encapsulation of spent nuclear fuel rods for geological disposal, SKB of Sweden is planning to use a system that consists of an outer copper canister and a cast iron insert (the KBS-3 concept). In 2007 Serco1 completed the set up of five model canister experiments at SKB's Aespoe laboratory and monitoring has continued since. The original aim of the model canister experiments was to examine how corrosion of the cast iron insert inside a copper canister would evolve with time, if water ingress through a small defect in the copper canister were to occur. Serco arranged manufacture and installation of five miniature copper canisters containing cast iron inserts, with 1 mm defects deliberately machined into the copper shell. The experiments use five small-scale model canisters (300 mm long x 150 mm diameter) that simulate the main features of the SKB canister design (hence the project name, 'MiniCan'). The main aim of the work is to examine how corrosion of the cast iron insert will evolve if a leak is present in the outer copper canister The experiments also included electrochemical equipment to monitor the corrosion behaviour of the model canisters in situ. In 2011 one of the experiments, Experiment 3, was removed f analysis. This report presents details of the procedures that were applied and the findings that were obtained from the analysis that was carried out on Experiment 3. To minimise exposure to air and to keep the contents of the experiment wet until the analysis was carried out, Experiment 3 was extracted from its borehole in August 2011 directly into a transfer tank that was filled with deaerated groundwater and placed in a purpose-built, water-filled and deoxygenated transfer flask. The transfer flask was then transported to the UK for dismantling and examination in a purpose-built anoxic glovebox that contained the appropriate lifting and cutting equipment for handling and sectioning the copper canister and the cast iron

Current transport across the pentacene/CVD-grown graphene interface for diode applications

International Nuclear Information System (INIS)

Berke, K; Tongay, S; McCarthy, M A; Rinzler, A G; Appleton, B R; Hebard, A F

2012-01-01

We investigate the electronic transport properties across the pentacene/graphene interface. Current transport across the pentacene/graphene interface is found to be strikingly different from transport across pentacene/HOPG and pentacene/Cu interfaces. At low voltages, diodes using graphene as a bottom electrode display Poole-Frenkel emission, while diodes with HOPG and Cu electrodes are dominated by thermionic emission. At high voltages conduction is dominated by Poole-Frenkel emission for all three junctions. We propose that current across these interfaces can be accurately modeled by a combination of thermionic and Poole-Frenkel emission. Results presented not only suggest that graphene provides low resistive contacts to pentacene where a flat-laying orientation of pentacene and transparent metal electrodes are desired but also provides further understanding of the physics at the organic semiconductor/graphene interface. (paper)

Current transport across the pentacene/CVD-grown graphene interface for diode applications.

Science.gov (United States)

Berke, K; Tongay, S; McCarthy, M A; Rinzler, A G; Appleton, B R; Hebard, A F

2012-06-27

We investigate the electronic transport properties across the pentacene/graphene interface. Current transport across the pentacene/graphene interface is found to be strikingly different from transport across pentacene/HOPG and pentacene/Cu interfaces. At low voltages, diodes using graphene as a bottom electrode display Poole–Frenkel emission, while diodes with HOPG and Cu electrodes are dominated by thermionic emission. At high voltages conduction is dominated by Poole–Frenkel emission for all three junctions. We propose that current across these interfaces can be accurately modeled by a combination of thermionic and Poole–Frenkel emission. Results presented not only suggest that graphene provides low resistive contacts to pentacene where a flat-laying orientation of pentacene and transparent metal electrodes are desired but also provides further understanding of the physics at the organic semiconductor/graphene interface.

Review of SKB's Safety Assessment SR-Can: Contributions in Support of SKI's and SSI's Review by External Consultants

Energy Technology Data Exchange (ETDEWEB)

2008-03-15

The Swedish Nuclear Fuel and Waste Management Co (SKB) plans to submit a license application for the construction of a repository for spent nuclear fuel in Sweden 2010. In support of this application SKB will present a safety report, SR-Site, on the repository's long-term safety and radiological consequences. As a preparation for SR-Site, SKB published the preliminary safety assessment SR-Can in November 2006. The purposes were to document a first evaluation of long-term safety for the two candidate sites at Forsmark and Laxemar and to provide feedback to SKB's future programme of work. An important objective of the authorities' review of SR-Can is to provide guidance to SKB on the complete safety reporting for the license application. The authorities have engaged external experts for independent modelling, analysis and review, with the aim to provide a range of expert opinions related to the sufficiency and appropriateness of various aspects of SR-Can. The conclusions and judgments in this report are those of the authors and may not necessarily coincide with those of SKI and SSI. The authorities own review will be published separately (SKI Report 2008:23, SSI Report 2008:04 E). This report compiles contributions from several specific research projects. The separate reviews cover topics regarding the engineered barrier system, the quality assurance, the climate evolution and its effects, and the ecosystems and environmental impacts. All contributions are in English apart from the review concerning ecosystems and environmental impacts, which is presented in Swedish

Review of SKB's Work on Coupled THM Processes Within SR-Can. External review contribution in support of SKI's and SSI's review of SR-Can

Energy Technology Data Exchange (ETDEWEB)

Rutqvist, Jonny; Chin-Fu Tsang (Lawrence Berkeley National Laboratory, Berkeley, CA (US))

2008-03-15

In this report, we scrutinize the work by the Swedish Nuclear Fuel and Waste Management Company (SKB) related to coupled thermal, hydrological and mechanical (THM) processes within the SR-Can project. SR-Can is SKB's preliminary assessment of long-term safety for a KBS-3 nuclear waste repository, and is a preparation stage for the SR-Site assessment, the report that will be used in SKB's application for a final repository. We scrutinize SKB's work related to THM processes through review and detailed analysis, using an independent modeling tool. The modeling tool is applied to analyze coupled THM processes at the two candidate sites, Forsmark and Laxemar, using data defined in SKB's site description models for respective sites. In this report, we first provide a brief overview of SKB's work related to analysis of the evolution of coupled THM processes as presented in SRCan, as well as supporting documents. In this overview we also identify issues and assumptions that we then analyze using our modeling tool. The overview and subsequent independent model analysis addresses issues related to near-field behavior, such as buffer resaturation and the evolution of the excavation-disturbed zone, as well as far-field behavior, such as stress induced changes in hydrologic properties. Based on the review and modeling conducted in this report, we conclude by identifying a number of areas of weaknesses, where we believe further work and clarifications are needed. Some of the most important ones are summarized below: 1) We found that SKB's calculation of peak temperature might not have been conducted for the most conservative case of extreme drying of the buffer under dry rock conditions and an unexpectedly high thermal diffusion coefficient. Our alternative analysis indicates that temperatures close to 100 might be achieved under unfavorable (and perhaps unexpected) conditions in which the buffer is dried to below 20% near the canister. We believe

Low-ph injection grout for deep repositories. Summary report from a co-operation project between NUMO (Japan), Posiva (Finland) and SKB (Sweden)

Energy Technology Data Exchange (ETDEWEB)

Boden, A. (ed.) [SwedPower Ab, Stockholm (Sweden); Sievaenen, U. (ed.) [JP-Suoraplan Oy, Vantaa (Finland)

2006-02-15

This report summarises results achieved in the joint SKB, Posiva and NUMO project 'Injection grout for deep repositories'. The work has been carried out in four subprojects with SKB and Posiva as responsible for two sub-projects each. This report summarises the original reporting. Posiva was responsible for the studies on low-pH cementitious grout, while SKB was responsible for the studies on non-cementitious grout. The work was done by literature surveys, laboratory analyses and field tests A result of the project is that there are both low-pH cementitious material for grouting larger fractures ((>-) 100 {mu}m) and non-cementitious material for grouting smaller fractures ((<-) 100 {mu}m) that will, after further optimisation work, be recommended for grouting of deep repositories. This project concentrated on the technical development of properties for the low pH grouts. Long-term safety and environmental aspects and durability of materials were preliminarily considered. Continued evaluations have to be carried out. (orig.)

Description of background data in the SKB database GEOTAB

International Nuclear Information System (INIS)

Eriksson, E.; Sehlstedt, S.

1989-02-01

During the research and development program performed by SKB for the final disposal of spent nuclear fuel, a large quantity of geoscientific data was collected. Most of this data was stored in a database called GEOTAB. This report describes data within the background data group. This data provides information on the location of areas studied, borehole positions and also some drilling information. The background data group (subject), called BGR, is divided into several subgroups (methods): BGAREA area background data; BGDRILL drilling information; BGDRILLP drill penetration data; BGHOLE borehole information; BGTABLES number of rows in a table, and BGTOLR data table tolerance. A method consists of one or several data tables. In each chapter a method and its data tables are described. (orig./HP)

The SSI and SKI review of the updated Final Safety Report for SFR 1 issued by SKB. Review report; SSI:s och SKI:s granskning av SKB:s uppdaterade Slutlig Saekerhetsrapport foer SFR 1. Granskningsrapport

Energy Technology Data Exchange (ETDEWEB)

Avila, Rodolfo; Jensen, Mikael; Larsson, Carl-Magnus; Lund, Ingemar; Loefgren, Tomas; Moberg, Leif; Norden, Maria; Wiebert, Anders [Swedish Radiation Protection Authority, Stockholm (Sweden); Berglund, Thomas; Dverstorp, Bjoern; Hedberg, Bengt; Kautsky, Fritz; Lilja, Christina; Simic, Eva; Stroemberg, Bo; Sundstroem, Benny; Toverud, Oeivind; Wingefors, Stig; Zika, Helmuth [Swedish Nuclear Power Inspectorate, Stockholm (Sweden)

2003-11-01

The repository for operational radioactive wastes in Sweden, SFR1, has been the object for a new safety assessment study by SKB (The Swedish Nuclear Fuel and Waste Management Co.). The findings of the review group will form the basis for decisions by the authorities on the provisions for the future operation of the repository.

Shunt attachment and method for interfacing current collection systems

Science.gov (United States)

Denney, Paul E.; Iyer, Natraj C.; Hannan, III, William F.

1992-01-01

A composite brush to shunt attachment wherein a volatile component of a composite but mostly metallic brush, used for current collection purposes, does not upon welding or brazing, adversely affect the formation of the interfacial bond with a conductive shunt which carries the current from the zone of the brush. The brush to shunt attachment for a brush material of copper-graphite composite and a shunt of copper, or substituting silver for copper as an alternative, is made through a hot isostatic pressing (HIP). The HIP process includes applying high pressure and temperature simultaneously at the brush to shunt interface, after it has been isolated or canned in a metal casing in which the air adjacent to the interface has been evacuated and the interfacial area has been sealed before the application of pressure and temperature.

Comments on SKB's SFL 3-5 preliminary performance assessment

International Nuclear Information System (INIS)

Wilmot, R.D.; Crawford, M.B.

2000-01-01

Recently introduced regulations in Sweden have established an individual risk criterion ( -6 per year) for the long-term performance of repositories for the disposal of radioactive wastes. SKB has not focused its assessment of SFL 3-5 on demonstrating compliance with this regulation. Instead, SKB has calculated individual dose and provided a comparison with an annual individual dose of 14 iSv (derived from the risk criteria using the ICRP's dose-risk conversion factor of 0.073 per Sv). The justification of this approach is that probabilities do not need to be determined if doses are less than the dose equivalent to the risk criterion. However, there is insufficient information regarding uncertainty provided in the documentation of the SFL 3-5 assessment to determine whether this approach is reasonable. SKB's parallel assessment of a repository for spent fuel using the KBS-3 concept (SR 97) accounts for uncertainty by specifying a 'reasonable' and a 'pessimistic' value for uncertain parameters in the assessment calculations. Although there are problems with the way probabilities have been assigned to these values, this approach does indicate where there are significant uncertainties. The SFL 3-5 PA does not include a structured approach to defining uncertainty, although a number of assumptions and parameter values are stated to be conservative. As a preliminary assessment, there is insufficient information to identify key uncertainties or sensitivities, or to determine where further work should be focused. Any assessment requires the use of expert judgement to determine how the assessment is conducted, what modelling approach to use, what features, events and processes (FEPs) could potentially affect the disposal system, which FEPs should be included in the conceptual models, and which scenarios should be assessed. Judgements are also required in determining how to parameterize the models, and this may extend to formal expert elicitation for particular parameter

Final report of the AECL/SKB Cigar Lake analog study

International Nuclear Information System (INIS)

Cramer, J.J.

1994-07-01

The Cigar Lake uranium deposit is located in northern Saskatchewan, Canada. The 1.3-billion-year-old deposit is located at a depth of about 450 m below surface in a water-saturated sandstone at the unconformity contact with the high-grade metamorphic rocks of the Canadian Shield. The uranium mineralization, consisting primarily of uraninite (UO 2 ), is surrounded by a clay-rich halo in both sandstone and basement rocks, and remains extremely well preserved and intact. The average grade of the mineralization is ∼ 8 wt.% U; locally grades are as high as ∼ 55 wt.%U. The Cigar lake deposit has many features that parallel those being considered within the Canadian concept for disposal of nuclear fuel waste. Specifically, the deposit provides analog information relevant to the stability of UO 2 fuel waste, the performance of clay-based barriers, radionuclide migration, colloid formation, radiolysis, fission-product geochemistry and general aspects of water-rock interaction. The main geochemical studies on this deposit focus on the evolution of groundwater compositions in the deposit and on their redox chemistry with respect to the uranium, iron and sulphide systems. Since 1984, through cooperation from the owners of the Cigar lake deposit, analog studies have been conducted. AECL, with support from Ontario Hydro under the auspices of the CANDU Owners Group, initiated international participation in 1989 through collaboration with the Swedish Nuclear Fuel and Waste Management Company (SKB) and, more recently, with the Los Alamos National Laboratory (LANL). This report gives the results of the various studies carried out during the 3-year collaboration between AECL and SKB, as well as a summary of the LANL study. It provides detailed information on the generated databases and models, and integrates this information into conclusions for use in safety assessment of the Canadian, Swedish and United States disposal concepts. 15 refs., 25 figs., 55 tabs

Evaluation of cost estimates and calculation methods used by SKB

International Nuclear Information System (INIS)

1994-01-01

The Swedish Nuclear Fuel Management Co. (SKB) has estimated the costs for decommissioning the swedish nuclear power plants and managing the nuclear wastes in a 'traditional' manner i.e. by handling uncertainties through percentage additions. A 'normal' addition is used for uncertainties in specified technical systems. 'Extra' additions are used for systems uncertainties. An alternative method is suggested, using top-down principles for uncertainties, which should be applied successively, giving higher precision as the knowledge accumulates. This type of calculation can help project managers to identify and deal with areas common to different partial projects. A first step in this direction would be to perform sensitivity analyses for the most important calculation parameters. 21 refs

Description of geophysical data in the SKB database GEOTAB

International Nuclear Information System (INIS)

Sehlstedt, S.

1988-02-01

For the storage of different types of data collected by SKB a database called Geotab has been created. The following data are stored in the database: Background data, geological data, geophysical data, hydrogeological data, hydrochemical data. This report describes the data flow for different types of geophysical measurements. The descriptions start with measurements and end with the storage of data in Geotab. Each process and the resulting data volume is presented separately. The geophysical measurements have been divided into the following subjects: Geophysical ground surface measurements, profile measurements; geophysical ground surface measurements, grid net measurements; geophysical borehole logging; petrophysical measurements. Each group of measurements is described in an individual chapter. In each chapter several measuring techniques are described and each method has a data table and a flyleaf table in Geotab. (orig.)

SKB/TVO ice age scenario

International Nuclear Information System (INIS)

Ahlbom, K.; Aeikaes, T.; Ericsson, L.O.

1991-06-01

Ice ages have repeatedly occurred throughout geological history, and it is likely that they will also occur in the time-span considered for the disposal of nuclear fuel. Based on the present status of knowledge, this report discusses when future ice ages will occur and the possible changes in the geosphere that might be of importance for repository performance. The report is intended to be used as a basis when developing scenarios for safety analysis of final repository for spent nuclear fuel. Both the ACLIN and Imbrie and Imbrie models suggest stadials (glaciations) at c. 20000, 60000 and 100000 years from now. The ACLIN model also suggests a glaciation period around 5000 years ahead. The next interglacial period will occur at c. 75000 years, according to the Imbrie and Imbrie model, while the ACLIN model suggests that interglacial conditions will not appear until 125000 years form now. Other models strongly support the 60000 year glaciation event. To some extent there is also support for the 20000 and 5000 year events. For the purpose of the SKB/TVO scenario it is suggested that smaller or large glaciations will occur at 5000, 20000 and 60000 years form now. Following the last glaciation, interglacial conditions will prevail at 75000 years. Thus after the first glaciation (5000 years) this is the earliest time when most part of Sweden and Finland will once again be resettled by man. (25 refs.)

An Assessment of SKB's Performance Assessment Calculations in the Interim Main Report for the Safety Assessment SR-Can

International Nuclear Information System (INIS)

Maul, Philip; Robinson, Peter

2005-03-01

SKB have published their Interim Main Report of the safety assessment SR-Can, which is intended to establish the framework for what will be submitted in 2006 in support of a licence application for construction of the spent fuel encapsulation plant. This follows on from the SR-Can Planning Document published in 2003. The purpose of the Interim Report is stated to be to demonstrate the methodology that will be used for safety assessment. The present report evaluates the information provided in the Interim SR-Can Report that is relevant to the Performance Assessment (PA) calculations that SKB intend to undertake, using independent calculations to facilitate this process. SKB consider that the primary safety function is to isolate completely the fuel within the canisters over the entire assessment period. Should a canister be damaged, the secondary safety function is to ensure that any release is retarded and dispersed sufficiently to ensure that concentrations levels in the accessible environment cannot cause unacceptable consequences. In this report PA calculations are considered to include both a high-level representation of the evolution of the system (relevant to the primary safety function), and any subsequent radionuclide transport (relevant to the secondary safety function). The main conclusions drawn are: 1. The effects of climate evolution on engineered barriers have not been analysed in detail in the Interim Report, and this limits the usefulness of the preliminary calculations that have been undertaken. 2. A key aspect of SKB's approach is the use of an integrated near-field evolution model. The information provided on this model demonstrates its capability efficiently to reproduce calculations from individual process models, but insufficient information is given at the present time to justify statements about interactions between processes. In particular it is assumed that relatively short term thermal and resaturation processes do not affect the

SKI's Evaluation of SKB's RD and D Programme 95. Summary and Conclusions

International Nuclear Information System (INIS)

1996-07-01

In SKI's opinion, the Swedish Nuclear Fuel and Waste Management Co (SKB) has presented a research and development program which fulfills the basic requirements stipulated in the Act on Nuclear Activities. On the whole, the program is appropriate with regard to the development and evaluation of a method for the final disposal of spent nuclear fuel and nuclear waste in the Swedish bedrock. The quality of the supporting research program is high. However, in SKI's view, the General Siting Study should be supplemented with regard to certain points and the siting factors should be further specified

SKI's and SSI's joint review of the Swedish Nuclear Fuel and Waste Management Co's (SKB) safety report SR-Can; SKIs och SSIs gemensamma granskning av SKBs saekerhetsrapport SR-Can

Energy Technology Data Exchange (ETDEWEB)

Dverstorp, Bjoern; Stroemberg, Bo (and others)

2008-03-15

This report summarizes SKI's and SSI's joint review of the Swedish Nuclear Fuel and Waste Management Co's (SKB) safety report SR-Can (SKB TR-06-09). SR-Can is the first assessment of post-closure safety for a KBS-3 spent nuclear fuel repository at the candidate sites Forsmark and Laxemar, respectively. The analysis builds on data from the initial stage of SKB's surface-based site investigations and on data from full-scale manufacturing and testing of buffer and copper canisters. SR-Can can be regarded as a preliminary version of the safety report that will be required in connection with SKB's planned license application for a final repository in late 2009. The main purpose of the authorities' review is to provide feedback to SKB on their safety reporting as part of the pre-licensing consultation process. However, SR-Can is not part of the formal licensing process. In support of the authorities' review three international peer review teams were set up to make independent reviews of SR-Can from three perspectives, namely integration of site data, representation of the engineered barriers and safety assessment methodology, respectively. Further, several external experts and consultants have been engaged to review detailed technical and scientific issues in SR-Can. The municipalities of Oesthammar and Oskarshamn where SKB is conducting site investigations, as well NGOs involved in SKB's programme, have been invited to provide their views on SR-Can as input to the authorities' review. Finally, the authorities themselves, and with the help of consultants, have used independent models to reproduce part of SKB's calculations and to make complementary calculations. All supporting review documents are published in SKI's and SSI's report series. The main findings of the review are: SKB's safety assessment methodology is overall in accordance with applicable regulations, but part of the methodology needs to be

Final report of the AECL/SKB Cigar Lake analog study

International Nuclear Information System (INIS)

Cramer, J.

1994-05-01

The Cigar Lake uranium deposit is located in northern Saskatchewan, Canada. The 1.3-billion-year-old deposit is located at a depth of about 450 m below surface in a water-saturated sandstone at the unconformity contact with the high-grade metamorphic rocks of the Canadian Shield. The Cigar Lake deposit has many features that parallel those being considered within the Canadian concept for disposal of nuclear fuel waste. The study of these natural structures and processes provides valuable insight toward the eventual design and site selection of a nuclear fuel waste repository. The main feature of this analog is the absence of any indication on the surface of the rich uranium ore 450 m below. This indicates that the combination of natural barriers has been effective in isolating the uranium ore from the surface environment. More specifically, the deposit provides analog information relevant to the stability of UO 2 fuel waste, the performance of clay-based barriers, radionuclide migration, colloid formation, radiolysis, fission-product geochemistry and general aspects of water-rock interaction. The main geochemical studies on this deposit focus on the evolution of groundwater compositions in the deposit and on their redox chemistry with respect to the uranium, iron and sulphide systems. Since 1984, through cooperation from the owners of the Cigar Lake deposit, analog studies have been conducted. AECL, with support from Ontario Hydro under the auspices of the CANDU Owners Group, initiated international participation in 1989 through collaboration with the Swedish Nuclear Fuel and Waste Management Company (SKB) and, more recently, with the Los Alamos National Laboratory (LANL). This report gives the results of the various studies carried out during the 3-year collaboration between AECL and SKB, as well as a summery of the LANL study. It provides detailed information on the generated databases and models, and integrates this information into conclusions for use in safety

Technical note 1. Review of the Geomicrobiological Aspects of SKB's Licence Application for a Spent Nuclear Fuel Repository in Forsmark, Sweden

International Nuclear Information System (INIS)

Parkes, R. John

2011-10-01

The report reviews whether the research work by SKB has been adequately comprehensive to describe the influence of microbial activity for sulphide production at repository depth. The report also documents any uncertainties with regard to predictions of rates and consequences of microbial sulphide production. SKB's assessment relies almost entirely on the results of the research that they commissioned from the Univ. of Goeteborg (Pedersen, 2010, Masurat et al., 2010a, b). This is not an unreasonable position, as there is no directly comparable research available. However, there is considerable literature demonstrating continued activity of sulphate-reducing bacteria over geological time scales and enhanced activity of sulphate-reducing bacteria in interaction with metals and corrosion, that should also be taken into consideration when assessing potential microbially influenced corrosion (Beech and Sunner, 2007) of the copper canister

Interface modulated currents in periodically proton exchanged Mg doped lithium niobate

Energy Technology Data Exchange (ETDEWEB)

Neumayer, Sabine M.; Rodriguez, Brian J., E-mail: brian.rodriguez@ucd.ie, E-mail: gallo@kth.se [School of Physics, University College Dublin, Belfield, Dublin 4 (Ireland); Conway Institute of Biomolecular and Biomedical Research, University College Dublin, Belfield, Dublin 4 (Ireland); Manzo, Michele; Gallo, Katia, E-mail: brian.rodriguez@ucd.ie, E-mail: gallo@kth.se [Department of Applied Physics, KTH-Royal Institute of Technology, Roslagstullbacken 21, 10691 Stockholm (Sweden); Kholkin, Andrei L. [Department of Physics and CICECO-Aveiro Institute of Materials, 3810-193 Aveiro, Portugal and Institute of Natural Sciences, Ural Federal University, 620000 Ekaterinburg (Russian Federation)

2016-03-21

Conductivity in Mg doped lithium niobate (Mg:LN) plays a key role in the reduction of photorefraction and is therefore widely exploited in optical devices. However, charge transport through Mg:LN and across interfaces such as electrodes also yields potential electronic applications in devices with switchable conductivity states. Furthermore, the introduction of proton exchanged (PE) phases in Mg:LN enhances ionic conductivity, thus providing tailorability of conduction mechanisms and functionality dependent on sample composition. To facilitate the construction and design of such multifunctional electronic devices based on periodically PE Mg:LN or similar ferroelectric semiconductors, fundamental understanding of charge transport in these materials, as well as the impact of internal and external interfaces, is essential. In order to gain insight into polarization and interface dependent conductivity due to band bending, UV illumination, and chemical reactivity, wedge shaped samples consisting of polar oriented Mg:LN and PE phases were investigated using conductive atomic force microscopy. In Mg:LN, three conductivity states (on/off/transient) were observed under UV illumination, controllable by the polarity of the sample and the externally applied electric field. Measurements of currents originating from electrochemical reactions at the metal electrode–PE phase interfaces demonstrate a memresistive and rectifying capability of the PE phase. Furthermore, internal interfaces such as domain walls and Mg:LN–PE phase boundaries were found to play a major role in the accumulation of charge carriers due to polarization gradients, which can lead to increased currents. The insight gained from these findings yield the potential for multifunctional applications such as switchable UV sensitive micro- and nanoelectronic devices and bistable memristors.

Sub-bandgap photonic base current method for characterization of interface states at heterointerfaces in heterojunction bipolar transistors

International Nuclear Information System (INIS)

Shin, H. T.; Kim, K. H.; Kim, K. S.

2004-01-01

In this paper, we propose a novel photonic base current analysis method to characterize the interface states in heterojunction bipolar transistors (HBTs) by using the photonic I-V characteristics under sub-bandgap photonic excitation. For the photonic current-voltage characterization of HBTs, an optical source with a photon energy less than the bandgap energy of Al 0.3 Ga 0.7 As and GaAs (E ph = 0.95 eV g,AlGaAs = 1.79 eV, E g,GaAs = 1.45 eV) is employed for the characterization of the interface states distributed in the photo-responsive energy band (E C - 0.95 ≤ E it ≤ E C ) in emitter-base heterojunction at HBTs. The proposed novel method, which is applied to bipolar junction transistors for the first time, is simple, and an accurate analysis of interface traps in HBTs is possible. By using the photonic base-current and the dark-base-current, we qualitatively analyze the interface trap at the Al 0.3 Ga 0.7 As/GaAs heterojunction interface in HBTs.

Description of geophysical data in the SKB database GEOTAB. Version 2

International Nuclear Information System (INIS)

Sehlstedt, S.

1991-01-01

For the storage of different types of data collected by SKB a database called GEOTAB has been created. The following data is stored in the database: Background data, geological data, geophysical data, hydrogeological and meteorological data, hydrochemical data, and tracer tests. This report describes the data flow for different types of geophysical measurement. The descriptions start with measurement and end with the storage of data in GEOTAB. Each process and the resulting data volume is presented separately. The geophysical measurements have been divided into the following subjects: Geophysical ground surface measurements, geophysical borehole logging, and petrophysical measurements. Each group of measurements is described in an individual chapter. In each chapter several measuring techniques are described and each method has a data table and a flyleaf table in GEOTAB. (author)

Spin-independent transparency of pure spin current at normal/ferromagnetic metal interface

Science.gov (United States)

Hao, Runrun; Zhong, Hai; Kang, Yun; Tian, Yufei; Yan, Shishen; Liu, Guolei; Han, Guangbing; Yu, Shuyun; Mei, Liangmo; Kang, Shishou

2018-03-01

The spin transparency at the normal/ferromagnetic metal (NM/FM) interface was studied in Pt/YIG/Cu/FM multilayers. The spin current generated by the spin Hall effect (SHE) in Pt flows into Cu/FM due to magnetic insulator YIG blocking charge current and transmitting spin current via the magnon current. Therefore, the nonlocal voltage induced by an inverse spin Hall effect (ISHE) in FM can be detected. With the magnetization of FM parallel or antiparallel to the spin polarization of pure spin currents ({{\\boldsymbol{σ }}}sc}), the spin-independent nonlocal voltage is induced. This indicates that the spin transparency at the Cu/FM interface is spin-independent, which demonstrates that the influence of spin-dependent electrochemical potential due to spin accumulation on the interfacial spin transparency is negligible. Furthermore, a larger spin Hall angle of Fe20Ni80 (Py) than that of Ni is obtained from the nonlocal voltage measurements. Project supported by the National Basic Research Program of China (Grant No. 2015CB921502), the National Natural Science Foundation of China (Grant Nos. 11474184 and 11627805), the 111 Project, China (Grant No. B13029), and the Fundamental Research Funds of Shandong University, China.

Utilization of transmission probabilities in the calculation of unit-cell by the interface-current method

International Nuclear Information System (INIS)

Queiroz Bogado Leite, S. de.

1989-10-01

A widely used but otherwise physically incorrect assumption in unit-cell calculations by the method of interface currents in cylindrical or spherical geometries, is that of that of isotropic fluxes at the surfaces of the cell annular regions, when computing transmission probabilities. In this work, new interface-current relations are developed without making use of this assumption and the effects on calculated integral parameters are shown for an idealized unit-cell example. (author) [pt

Treatment of barrier evolution: the SKB perspective

International Nuclear Information System (INIS)

Hedin, A.

2002-01-01

This paper serves as a point of departure for the discussions to be held within the Working Group of Technical Topic entitled 'Barriers and System Performances within a safety case: Their functioning and Evolution with Time'. The paper gives the SKB perspective of the issues to be discussed within the Working Group for this Topic. The following issues to be discussed by the Working Group are: What is the role of each barrier as a function of time or in the different time frames? What is its contribution to the overall system performance or safety as a function of time? Which are the main uncertainties on the performance of barriers in the timescales? To what extent should we enhance the robustness of barriers because of the uncertainties of some component behaviour with time? What is the requested or required performance versus the expected or realistic or conservative behaviour with time? How are these safety margins used as arguments in a safety case? What is the issue associated with the geosphere stability for different geological systems? How is barriers and system performances as a function of time evaluated (and presented and communicated) in a safety case? What kind of measures are used for siting, designing and optimising robust barriers corresponding to situations that can vary with time? Are human actions considered to be relevant? (authors)

Aespoe hard rock laboratory. Current research projects 1998

Energy Technology Data Exchange (ETDEWEB)

NONE

1998-12-31

In 1986 SKB decided to construct the Aespoe Hard Rock Laboratory (HRL) in order to provide an opportunity for research, development and demonstration in a realistic and undisturbed underground rock environment down to the depth planned for the future deep repository. The focus of current and future work is on development and testing of site characterization methods, verification of models describing the function of the natural and engineered barriers and development, testing, and demonstration of repository technology. The program has been organised so that all important steps in the development of a repository are covered, in other words the Aespoe HRL constitutes a `dress rehearsal` for the Swedish deep geological repository for spent fuel and other long-lived waste. Geoscientific investigations on Aespoe and nearby islands began in 1986. Aespoe was selected as the site for the laboratory in 1988. Construction of the facility, which reaches a depth of 460 m below the surface, began in 1990 and was completed in 1995. A major milestone had been reached in 1996 with the completion of the pre-investigation and construction phases of the Aespoe HRL. The comprehensive research conducted has permitted valuable development and verification of site characterization methods applied from the ground surface, boreholes, and underground excavations. The results of this research are summarised in the book `Aespoe Hard Rock Laboratory - 10 years of Research` published by SKB in 1996. The Operating Phase of the Aespoe HRL began in 1995 and is expected to continue for 15-20 years, that is until the first stage of the development of the Swedish deep geological repository for spent nuclear fuel is expected to be completed. A number of research projects were initiated at the start of the Operating Phase. Most of these projects have made substantial progress since then and important results have been obtained. The purpose of this brochure is to provide a brief presentation of the

Aespoe hard rock laboratory. Current research projects 1998

International Nuclear Information System (INIS)

1998-01-01

In 1986 SKB decided to construct the Aespoe Hard Rock Laboratory (HRL) in order to provide an opportunity for research, development and demonstration in a realistic and undisturbed underground rock environment down to the depth planned for the future deep repository. The focus of current and future work is on development and testing of site characterization methods, verification of models describing the function of the natural and engineered barriers and development, testing, and demonstration of repository technology. The program has been organised so that all important steps in the development of a repository are covered, in other words the Aespoe HRL constitutes a 'dress rehearsal' for the Swedish deep geological repository for spent fuel and other long-lived waste. Geoscientific investigations on Aespoe and nearby islands began in 1986. Aespoe was selected as the site for the laboratory in 1988. Construction of the facility, which reaches a depth of 460 m below the surface, began in 1990 and was completed in 1995. A major milestone had been reached in 1996 with the completion of the pre-investigation and construction phases of the Aespoe HRL. The comprehensive research conducted has permitted valuable development and verification of site characterization methods applied from the ground surface, boreholes, and underground excavations. The results of this research are summarised in the book 'Aespoe Hard Rock Laboratory - 10 years of Research' published by SKB in 1996. The Operating Phase of the Aespoe HRL began in 1995 and is expected to continue for 15-20 years, that is until the first stage of the development of the Swedish deep geological repository for spent nuclear fuel is expected to be completed. A number of research projects were initiated at the start of the Operating Phase. Most of these projects have made substantial progress since then and important results have been obtained. The purpose of this brochure is to provide a brief presentation of the

The post-closure radiological safety case for a spent fuel repository in Sweden - An international peer review of the SKB license-application study of March 2011

International Nuclear Information System (INIS)

2012-01-01

Sweden is at the forefront among countries developing plans for a deep geological repository of highly radioactive waste. There is no such repository in operation yet worldwide, but Sweden, Finland and France are approaching the licensing stage. At the request of the Swedish government, the NEA organised an international peer review of the post-closure radiological safety case produced by the Swedish Nuclear Fuel and Waste Management Company (SKB) in support of the application for a general licence to construct and operate a spent nuclear fuel geological repository in the municipality of Oesthammar. The purpose of the review was to help the Swedish government, the public and relevant organisations by providing an international reference regarding the maturity of SKB's spent fuel disposal programme vis-a-vis best practices in long-term disposal safety and radiological protection. The International Review Team (IRT) consisted of ten international specialists, who were free of conflict of interest with the SKB and brought complementary expertise to the review. This report provides the background and findings of the international peer review. The review's findings are presented at several levels of detail in order to be accessible to both specialist and non-specialist readers

Interface inductive currents and carrier injection in hybrid perovskite single crystals

Science.gov (United States)

Kovalenko, Alexander; Pospisil, Jan; Krajcovic, Jozef; Weiter, Martin; Guerrero, Antonio; Garcia-Belmonte, Germà

2017-10-01

Interfaces between the absorbing perovskite and transporting layers are gaining attention as the key locus that governs solar cell operation and long term performance. The interplay of ionic and electronic processes, along with the asymmetrical architecture of any solar cell, makes the interpretation of electrical measurements always inconclusive. A strategy to progress in relating electric responses, operating mechanisms, and device architecture relies upon simplifying the probing structure. Macroscopic CH3NH3PbBr3 single crystals with symmetrical contacts are tested by means of long-time current transient and impedance spectroscopy. It is observed that interfaces govern carrier injection to (and extraction from) perovskite layers through an inductive (negative capacitance) mechanism with a response time in the range of ˜ 1 - 100 s under dark conditions and inert atmosphere. Current transient exhibits a slow recovering after the occurrence of an undershoot, signaling a complex carrier dynamics which involves changes in surface state occupancy.

Porosity, sorption and diffusivity data compiled for the SKB 91 study

International Nuclear Information System (INIS)

Brandberg, F.; Skagius, K.

1991-04-01

The SKB 91 study is an integrated safety analysis of the KBS-3 concept of a repository located in the Finnsjoen area. For this study, values of important transport parameters in the bentonite backfill and in the rock are proposed. K d -values, diffusivities and diffusion porosity for different elements in compacted MX-80 bentonite are based on experimental data found in the literature. With regard to sorption, both a best estimate and a conservative value is given. Because sorption on bentonite is very much dependent on the conditions prevailing and experimental data are limited and not necessary representative for the conditions expected in the repository, the proposed best estimate values may include large uncertainties. Data proposed for rock are matrix diffusivities, matrix porosity and diffusivity in mobile bulk water. These values are based on experimental results on Finnsjoe rock. (au)

Deep repository for long-lived low- and intermediate-level waste in Sweden (SFL 3-5): An international peer review of SKB 's preliminary safety assessment

Energy Technology Data Exchange (ETDEWEB)

Chapman, N. [QuantiSci Ltd, Melton Mowbray (United Kingdom); Apted, M. [Monitor Scientific, Denver, CO (United States); Glasser, F. [Univ. of Aberdeen (United Kingdom). Dept. of Chemistry; Kessler, J. [EPRI, Inc., Palo Alto, CA (United States); Voss, C. [US Geological Survey, Reston, VA (United States)

2000-10-01

The SKB safety assessment of the SFL 3-5 repository (the planned deep repository for long-lived low- and intermediate level waste) can be read in two contexts: as a preliminary evaluation of the performance and design options for a repository that will not be required for perhaps forty years; or as an evaluation of a repository that might need to be sited together with the SFL 2 spent fuel repository, and whose nature and performance might thus need to be understood to a level that can be used to make wider programmatic decisions during the next five years. These two 'assessment contexts' are quite different, and an overarching issue is the fact that it was not clear to the review team which view to take. Apparently, SKB would tend towards the first context. However, it is not at all apparent to the reviewers why the second context should not be the predominant driver in the near future. The review team notes that the SFL 3-5 repository, as modelled by SKB, gives rise to potentially perceptible radionuclide releases to the environment on a timescale of hundreds of years after closure. This is in contrast to the SR 97 assessment for the SFL 2 spent fuel repository, which base scenario predicts no releases over a million year timescale. It is clear that according to SKB's SR97 and SFL3-5 analyses, for co-located facilities, it is this repository that has the potential for real radiological impacts in the immediate future. An initial recommendation from the review, is that SKB and the regulatory authorities consider which context is appropriate to the current status of the Swedish programme. This is important, because an overall impression of the reviewers is that the analysis would not be 'fit for purpose' if it were needed to assist with decision-making by SKB or the regulatory agencies. There are too many unanswered questions, and the overall impression of the safety concept is one of some fragility. Because there is no real design basis

Deep repository for long-lived low- and intermediate-level waste in Sweden (SFL 3-5): An international peer review of SKB 's preliminary safety assessment

International Nuclear Information System (INIS)

Chapman, N.; Apted, M.; Glasser, F.; Voss, C.

2000-10-01

The SKB safety assessment of the SFL 3-5 repository (the planned deep repository for long-lived low- and intermediate level waste) can be read in two contexts: as a preliminary evaluation of the performance and design options for a repository that will not be required for perhaps forty years; or as an evaluation of a repository that might need to be sited together with the SFL 2 spent fuel repository, and whose nature and performance might thus need to be understood to a level that can be used to make wider programmatic decisions during the next five years. These two 'assessment contexts' are quite different, and an overarching issue is the fact that it was not clear to the review team which view to take. Apparently, SKB would tend towards the first context. However, it is not at all apparent to the reviewers why the second context should not be the predominant driver in the near future. The review team notes that the SFL 3-5 repository, as modelled by SKB, gives rise to potentially perceptible radionuclide releases to the environment on a timescale of hundreds of years after closure. This is in contrast to the SR 97 assessment for the SFL 2 spent fuel repository, which base scenario predicts no releases over a million year timescale. It is clear that according to SKB's SR97 and SFL3-5 analyses, for co-located facilities, it is this repository that has the potential for real radiological impacts in the immediate future. An initial recommendation from the review, is that SKB and the regulatory authorities consider which context is appropriate to the current status of the Swedish programme. This is important, because an overall impression of the reviewers is that the analysis would not be 'fit for purpose' if it were needed to assist with decision-making by SKB or the regulatory agencies. There are too many unanswered questions, and the overall impression of the safety concept is one of some fragility. Because there is no real design basis presented, no thorough

Review of spent fuel related issues in SKB's SR 97

International Nuclear Information System (INIS)

Grambow, B.

2000-01-01

example, it is shown that high uncertainties in release properties result from the (uncertain) choices in this partitioning. The analyses of the fuel performance in the case of groundwater access is in SR 97 is based on the assumption that the fuel integrity and fuel oxidation states do not alter prior to water access. No account is taken for potential fuel oxidation in a defected canister during interim storage or disposal. Fuel oxidation at surface temperatures of 200-400 deg C during storage or disposal is expected to be fast. This process is known to strongly alter fuel integrity. Special attention is given to processes and models which describe spent fuel dissolution and radionuclide release in the case of groundwater access to the fuel. Based on a detailed discussion of the current state of knowledge of radiation assisted fuel dissolution models it is concluded that the long term corrosion rates of the fuel matrix used by SKB with a value of 10 -8 /year are overly optimistic. The proposed long-term corrosion rate is considered to be independent on environmental parameters such as pH, pCO 2 or of fuel specific parameters such as burnup or surface area. As discussed in this review, these assumptions are in conflict with experimental observations. It is concluded that the SR 97 approach to the assessment for radionuclide release from spent fuel assemblies is characterized by an optimistic view which is not necessarily incorrect but which is not sustained by the base of current knowledge. A significant drawback is that the source term is not quantified based on the experimental results of a more than 20 year lasting spent fuel leaching program performed in the Studsvik laboratory, but rather on theoretical concepts whose quantification is poorly documented and on experimental data obtained from unirradiated UO 2

Resolving Overlimiting Current Mechanisms in Microchannel-Nanochannel Interface Devices

Science.gov (United States)

Yossifon, Gilad; Leibowitz, Neta; Liel, Uri; Schiffbauer, Jarrod; Park, Sinwook

2015-11-01

We present results demonstrating the space charge-mediated transition between classical, diffusion-limited current and surface-conduction dominant over-limiting currents in a shallow micro-nanochannel device. The extended space charge layer develops at the depleted micro-nanochannel entrance at high current and is correlated with a distinctive maximum in the dc resistance. Experimental results for a shallow surface-conduction dominated system are compared with theoretical models, allowing estimates of the effective surface charge at high voltage to be obtained. Further, we extend the study to microchannels of moderate to large depths where the role of various electro-convection mechanisms becomes dominant. In particular, electro-osmotic of the second kind and electro-osmotic instability (EOI) which competes each other at geometrically heterogeneous (e.g. undulated nanoslot interface, array of nanoslots) nanoslot devices. Also, these effects are also shown to be strongly modulated by the non-ideal permselectivity of the nanochannel.

An induced current method for measuring zeta potential of electrolyte solution-air interface.

Science.gov (United States)

Song, Yongxin; Zhao, Kai; Wang, Junsheng; Wu, Xudong; Pan, Xinxiang; Sun, Yeqing; Li, Dongqing

2014-02-15

This paper reports a novel and very simple method for measuring the zeta potential of electrolyte solution-air interface. When a measuring electrode contacts the electrolyte solution-air interface, an electrical current will be generated due to the potential difference between the electrode-air surface and the electrolyte solution-air interface. The amplitude of the measured electric signal is linearly proportional to this potential difference; and depends only on the zeta potential at the electrolyte solution-air interface, regardless of the types and concentrations of the electrolyte. A correlation between the zeta potential and the measured voltage signal is obtained based on the experimental data. Using this equation, the zeta potential of any electrolyte solution-air interface can be evaluated quickly and easily by inserting an electrode through the electrolyte solution-air interface and measuring the electrical signal amplitude. This method was verified by comparing the obtained results of NaCl, MgCl2 and CaCl2 solutions of different pH values and concentrations with the zeta potential data reported in the published journal papers. Copyright © 2013 Elsevier Inc. All rights reserved.

Geosciences research: cooperation with Swedish Nuclear Fuel and Waste Management Co. (SKB)

International Nuclear Information System (INIS)

1993-01-01

PNC has been participating in the research program of the Construction Phase in Aespoe Hard Rock Laboratory project (HRL project), an underground research laboratory project initiated by Swedish Nuclear Fuel and Waste Management Company (SKB), since 1991. The main purpose of participating in the HRL project is to apply site characterization, prediction and validation methodology of geological environment in the project to R and D program on geological disposal in Japan. The outcome from investigations for the 0-700 m section in the access tunnel has been evaluated to compare with predictions on geological-structure. This report gives the summary of R and D program on the HRL project and preliminary results on evaluation of geological-structural predictions for the 0-700 m section in the access tunnel. (author)

Environmental impact statements and public consultations on the repository. An outline of SKB's planning

International Nuclear Information System (INIS)

2001-09-01

In December 2000 SKB selected three locations for further investigations as possible sites for the Swedish repository for spent nuclear fuels, Simpevarp at Oskarshamn, Forsmark at Oesthammar and Tierp. Site investigations will be performed during 5-6 years, and will provide data for a site selection. In the application for the repository commission an environmental impact statement should be included, that has been object for consultations with authorities, local communities, other organizations and the public. These consultations will take place during the whole investigation period, and will give ample possibilities for all parties to give their views and to exert an influence on the EIS

Enhancement of spin Hall effect induced torques for current-driven magnetic domain wall motion: Inner interface effect

KAUST Repository

Bang, Do; Yu, Jiawei; Qiu, Xuepeng; Wang, Yi; Awano, Hiroyuki; Manchon, Aurelien; Yang, Hyunsoo

2016-01-01

We investigate the current-induced domain wall motion in perpendicular magnetized Tb/Co wires with structure inversion asymmetry and different layered structures. We find that the critical current density to drive domain wall motion strongly depends on the layered structure. The lowest critical current density ∼15MA/cm2 and the highest slope of domain wall velocity curve are obtained for the wire having thin Co sublayers and more inner Tb/Co interfaces, while the largest critical current density ∼26MA/cm2 required to drive domain walls is observed in the Tb-Co alloy magnetic wire. It is found that the Co/Tb interface contributes negligibly to Dzyaloshinskii-Moriya interaction, while the effective spin-orbit torque strongly depends on the number of Tb/Co inner interfaces (n). An enhancement of the antidamping torques by extrinsic spin Hall effect due to Tb rare-earth impurity-induced skew scattering is suggested to explain the high efficiency of current-induced domain wall motion.

Enhancement of spin Hall effect induced torques for current-driven magnetic domain wall motion: Inner interface effect

KAUST Repository

Bang, Do

2016-05-23

We investigate the current-induced domain wall motion in perpendicular magnetized Tb/Co wires with structure inversion asymmetry and different layered structures. We find that the critical current density to drive domain wall motion strongly depends on the layered structure. The lowest critical current density ∼15MA/cm2 and the highest slope of domain wall velocity curve are obtained for the wire having thin Co sublayers and more inner Tb/Co interfaces, while the largest critical current density ∼26MA/cm2 required to drive domain walls is observed in the Tb-Co alloy magnetic wire. It is found that the Co/Tb interface contributes negligibly to Dzyaloshinskii-Moriya interaction, while the effective spin-orbit torque strongly depends on the number of Tb/Co inner interfaces (n). An enhancement of the antidamping torques by extrinsic spin Hall effect due to Tb rare-earth impurity-induced skew scattering is suggested to explain the high efficiency of current-induced domain wall motion.

Transient nuclide release through the bentonite barrier -SKB 91

International Nuclear Information System (INIS)

Bengtsson, A.; Widen, H.

1991-05-01

A study of near-field radionuclide migration is presented. The study has been performed in the context of the SKB91 study which is a comprehensive performance assessment of disposal of spent fuel. The objective of the present study has been to enable the assessment of which nuclides can be screened out because they decay to insignificant levels already in the near-field of the repository. A numerical model has been used which describes the transient transport of radionuclides through a small hole in a HLW canister imbedded in bentonite clay into a fracture in the rock outside the bentonite. Calculations for more than twenty nuclides, nuclides with both high and low solubility have been made. The effect of sorption in the bentonite backfill is included. The size of the penetration hole was assumed to be constant up to time when the calculations were terminated, 500000 year after the deposition. The mass transport rate is controlled by diffusion. The model is three dimensional. The report describes the geometry of the modelled system, the assumptions concerning the transport resistances at the boundary conditions, the handling of the source term and obtained release curves. (au)

Vertically oriented graphene bridging active-layer/current-collector interface for ultrahigh rate supercapacitors.

Science.gov (United States)

Bo, Zheng; Zhu, Weiguang; Ma, Wei; Wen, Zhenhai; Shuai, Xiaorui; Chen, Junhong; Yan, Jianhua; Wang, Zhihua; Cen, Kefa; Feng, Xinliang

2013-10-25

Dense networks of graphene nanosheets standing vertically on a current collector can work as numerous electrically conductive bridges to facilitate charge transport and mitigate the constriction/spreading resistance at the interface between the active material and the current collector. The vertically oriented graphene-bridged supercapacitors present excellent rate and power capabilities. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Dynamics at Solid State Surfaces and Interfaces, Volume 1 Current Developments

CERN Document Server

Bovensiepen, Uwe; Wolf, Martin

2010-01-01

This two-volume work covers ultrafast structural and electronic dynamics of elementary processes at solid surfaces and interfaces, presenting the current status of photoinduced processes. Providing valuable introductory information for newcomers to this booming field of research, it investigates concepts and experiments, femtosecond and attosecond time-resolved methods, as well as frequency domain techniques. The whole is rounded off by a look at future developments.

SKB's safety case for a final repository license application

International Nuclear Information System (INIS)

Hedin, Allan; Andersson, Johan

2014-01-01

The safety assessment SR-Site is a main component in SKB's license application, submitted in March 2011, to construct and operate a final repository for spent nuclear fuel at Forsmark in the municipality of Oesthammar, Sweden. Its role in the application is to demonstrate long-term safety for a repository at Forsmark. The assessment relates to the KBS-3 disposal concept in which copper canisters with a cast iron insert containing spent nuclear fuel are surrounded by bentonite clay and deposited at approximately 500 m depth in saturated, granitic rock. The principal regulatory acceptance criterion, issued by the Swedish Radiation Safety Authority (SSM), requires that the annual risk of harmful effects after closure not exceed 10 -6 for a representative individual in the group exposed to the greatest risk. SSM's regulations also imply that the assessment time for a repository of this type is one million years after closure. The licence applied for is one in a stepwise series of permits, each requiring a safety report. The next step concerns a permit to start excavation of the repository and requires a preliminary safety assessment report (PSAR) covering both operational and post-closure safety. Later steps include permission to commence trial operation, to commence regular operation and to close the final repository. (authors)

Comments on 'SKB RD and D-Programme 98'. Focused on canister integrity and corrosion

International Nuclear Information System (INIS)

Bowyer, W.H.; Hermansson, H.P.

1999-04-01

According to the Act on Nuclear Activities the nuclear utilities are requested to submit a comprehensive programme for research and development every third year, aiming at the safe storage of radioactive waste produced by the nuclear power plants. The latest was published by SKB in September 1998 and is called the 'RDandD Programme 98'. The work presented in the present report was commissioned by SKI and is a result of reading the 'RDandD Programme 98' and related reports with focus on canister production, integrity and corrosion. We find that those parts of the programme often are difficult to follow owing to the lack of detail in the Programme and in one of the supporting reports. In our opinion this will make the work difficult to monitor by SKI and SKB. We also feel that the interpretation of information already available often is overoptimistic. As a consequence the difficulties ahead are understated and the programme is allowed to converge too quickly. We agree that the materials choices for both the inner and outer canisters are appropriate providing they both can be produced commercially and in a satisfactory metallurgical condition, that they can be quality assured and that no further unforeseen difficulties arise. We also agree that alternative technologies merit consideration for production of the outer canister and that alternative joining processes should be studied. We are actually concerned that greater prominence is not given to the alternatives in the programme. We believe that it should be possible to develop a satisfactory canister for disposal of high level nuclear waste according to the general method proposed by SKB and with the proposed capacity within the time-scale of the overall programme. We do not believe, however, that all the difficulties have been recognised. As a consequence of this the results to date are interpreted optimistically. We believe that progress should be subjected to more professional review within SKB and that a higher

A Single Rod Multi-modality Multi-interface Level Sensor Using an AC Current Source

Directory of Open Access Journals (Sweden)

Abdulgader Hwili

2008-05-01

Full Text Available Crude oil separation is an important process in the oil industry. To make efficient use of the separators, it is important to know their internal behaviour, and to measure the levels of multi-interfaces between different materials, such as gas-foam, foam-oil, oil-emulsion, emulsion-water and water-solids. A single-rod multi-modality multi-interface level sensor is presented, which has a current source, and electromagnetic modalities. Some key issues have been addressed, including the effect of salt content and temperature i.e. conductivity on the measurement.

SKI's Evaluation of SKB's RD and D Programme 95. Review Report

International Nuclear Information System (INIS)

1996-10-01

SKI (the Swedish Nuclear Power Inspectorate) has sent SKB's (the Swedish Nuclear Fuel and Waste Management Co.) RD and D Programme 95 to sixty authorities and organizations for review. 35 reviewing bodies have replied. In various ways, most of the comments are related to the decision-making process, both with regard to site selection and choice of method and only a small number of reviewing bodies have dealt with the more purely technical issues such as the function of the barriers and the safety assessment methodology. SKI's review of the programme is based on the premises of establishing whether and how the programme can fulfill its actual purpose to identify and implement solutions for the final disposal of the spent nuclear fuel from the Swedish nuclear power plants. SKI's statement to the Government includes a 'Summary and Conclusions' of the 'Review Report'. In (the present) 'Review Report' SKI reviews the programme and deals with comments from the other reviewing bodies. Furthermore, SKI has commissioned a separate report with the 'Comments of the Reviewing Bodies'. 32 refs

Current-voltage analysis of the record-efficiency CuGaSe2 solar cell: Application of the current separation method and the interface recombination model

International Nuclear Information System (INIS)

Saad, M.; Kasis, A.

2011-01-01

Current-voltage (j-V) characteristics of the record-efficiency CuGaSe 2 solar cell measured under several illumination levels are analyzed using a two-diode equation for a more accurate description of cell behavior. The contribution of each diode to the total cell j-V characteristic under illumination was estimated using the current separation method presented recently. This is performed in an effort to identify the distinctive features of this record-efficiency cell which have led to the up-to-date highest open circuit voltage of V o c = 946 mV and fill factor of FF = 66.5% for CuGaSe 2 solar cells. Furthermore, the interface recombination component of the cell current under illumination is quantitatively discussed applying the interface recombination model presented earlier. (author)

Review of spent fuel related issues in SKB's SR 97

Energy Technology Data Exchange (ETDEWEB)

Grambow, B. [Ecole des Mines de Nantes (France). SUBATECH-Laboratory

2000-12-01

an example, it is shown that high uncertainties in release properties result from the (uncertain) choices in this partitioning. The analyses of the fuel performance in the case of groundwater access is in SR 97 is based on the assumption that the fuel integrity and fuel oxidation states do not alter prior to water access. No account is taken for potential fuel oxidation in a defected canister during interim storage or disposal. Fuel oxidation at surface temperatures of 200-400 deg C during storage or disposal is expected to be fast. This process is known to strongly alter fuel integrity. Special attention is given to processes and models which describe spent fuel dissolution and radionuclide release in the case of groundwater access to the fuel. Based on a detailed discussion of the current state of knowledge of radiation assisted fuel dissolution models it is concluded that the long term corrosion rates of the fuel matrix used by SKB with a value of 10{sup -8}/year are overly optimistic. The proposed long-term corrosion rate is considered to be independent on environmental parameters such as pH, pCO{sub 2} or of fuel specific parameters such as burnup or surface area. As discussed in this review, these assumptions are in conflict with experimental observations. It is concluded that the SR 97 approach to the assessment for radionuclide release from spent fuel assemblies is characterized by an optimistic view which is not necessarily incorrect but which is not sustained by the base of current knowledge. A significant drawback is that the source term is not quantified based on the experimental results of a more than 20 year lasting spent fuel leaching program performed in the Studsvik laboratory, but rather on theoretical concepts whose quantification is poorly documented and on experimental data obtained from unirradiated UO{sub 2}.

Molecular Dynamics Study of the Separation Behavior at the Interface between PVDF Binder and Copper Current Collector

Directory of Open Access Journals (Sweden)

Seungjun Lee

2016-01-01

Full Text Available In Li-ion batteries, the mechanical strengths at the interfaces of binder/particle and binder/current collector play an important role in maintaining the mechanical integrity of the composite electrode. In this work, the separation behaviors between polyvinylidene fluoride (PVDF binders and copper current collectors are studied in the opening and sliding modes using molecular dynamics (MD simulations. The simulation shows that the separation occurs inside the PVDF rather than at the interface due to the strong adhesion between PVDF and copper. This fracture behavior is different from the behavior of the PVDF/graphite basal plane that shows a clear separation at the interface. The results suggest that the adhesion strength of the PVDF/copper is stronger than that of the PVDF/graphite basal plane. The methodology used in MD simulation can directly evaluate the adhesion strength at the interfaces of various materials between binders, substrates, and particles at the atomic scales. The proposed method can therefore provide a guideline for the design of the electrode in order to enhance the mechanical integrity for better battery performance.

Workshop on spent fuel performance, radionuclide chemistry and geosphere transport parameters, Lidingoe 2008: Overview and evaluation of recent SKB procedures

International Nuclear Information System (INIS)

Meinrath, Guenther; Stenhouse, Mike; Brown, Paul; Ekberg, Christian; Jegou, Christophe; Nitsche, Heino

2009-08-01

The safety assessment for disposal of spent nuclear fuel canister in the Swedish bedrock should thoroughly address the time period after a containment failure. Such a failure could be expected as a result of corrosion damage or mechanical failure due to rock movement. This report mainly covers some issues connected to parameters used for radionuclide transport calculations in the areas of spent fuel performance (for fuel in contact with groundwater), radionuclide chemistry, and sorption and geosphere transport parameters. Some examples of topics that are elaborated in some detail include statistical treatment of measurement data (for sorption measurements), handling of uncertainties in speciation calculations, use of triangular distributions in safety assessment and physical processes in connection with spent fuel aging. The results emerged from discussions among international experts at a workshop in May 2008. The purpose of this work is providing an overview of ongoing work within the Swedish Nuclear Fuel and Waste Management Co. (SKB), to provide ideas and suggestions for methodology development and to develop review capability within the SSM. The authors conclude that SKB's treatment of uncertainty in speciation calculations has improved, but that additional efforts in the area of error propagation are recommended. In efforts to condense the scope of utilised thermodynamic databases, the authors recommend that exclusion criteria should be explicitly stated. In the area of sorption, there is a need for more thorough analysis of errors in order to establish uncertainty ranges. The most essential improvements concern dose-limiting nuclides (e.g. Ra-226). Triangular distributions are often featured in SKB safety assessment, but it is not clear that the use of such distributions is based on a firm understanding of its properties. Regarding fuel performance, while safety assessment parameters are supported by measurement data there is still a need for better

Workshop on spent fuel performance, radionuclide chemistry and geosphere transport parameters, Lidingoe 2008: Overview and evaluation of recent SKB procedures

Energy Technology Data Exchange (ETDEWEB)

Meinrath, Guenther; Stenhouse, Mike; Brown, Paul; Ekberg, Christian; Jegou, Christophe; Nitsche, Heino

2009-08-15

The safety assessment for disposal of spent nuclear fuel canister in the Swedish bedrock should thoroughly address the time period after a containment failure. Such a failure could be expected as a result of corrosion damage or mechanical failure due to rock movement. This report mainly covers some issues connected to parameters used for radionuclide transport calculations in the areas of spent fuel performance (for fuel in contact with groundwater), radionuclide chemistry, and sorption and geosphere transport parameters. Some examples of topics that are elaborated in some detail include statistical treatment of measurement data (for sorption measurements), handling of uncertainties in speciation calculations, use of triangular distributions in safety assessment and physical processes in connection with spent fuel aging. The results emerged from discussions among international experts at a workshop in May 2008. The purpose of this work is providing an overview of ongoing work within the Swedish Nuclear Fuel and Waste Management Co. (SKB), to provide ideas and suggestions for methodology development and to develop review capability within the SSM. The authors conclude that SKB's treatment of uncertainty in speciation calculations has improved, but that additional efforts in the area of error propagation are recommended. In efforts to condense the scope of utilised thermodynamic databases, the authors recommend that exclusion criteria should be explicitly stated. In the area of sorption, there is a need for more thorough analysis of errors in order to establish uncertainty ranges. The most essential improvements concern dose-limiting nuclides (e.g. Ra-226). Triangular distributions are often featured in SKB safety assessment, but it is not clear that the use of such distributions is based on a firm understanding of its properties. Regarding fuel performance, while safety assessment parameters are supported by measurement data there is still a need for better

The Swedish Nuclear Power Inspectorate's evaluation of SKB's RD and D Program 98. Summary and conclusions

International Nuclear Information System (INIS)

1999-04-01

Compared to previous programmes, RD and D Programme 98 is focused to a greater extent on method and site selection and on issues relating to the decision-making process. This is natural, since the programme is now approaching the stage where vital decisions will have to be made. The RD and D Programme 98 report is supplemented by a background report 'Detailed Programme for Research and Development 1999-2004' as well as a number of main references 'System Reporting', 'Alternative methods', 'Criteria for Site Evaluation' and the 'North-South/Coast-Interior' report. In addition, a number of references are available in the form of county-specific general siting studies, feasibility studies etc. SKI has distributed RD and D Programme 98 to sixty-three reviewing bodies for comment. The reviewing bodies include universities and institutes of technology, local safety committees, municipalities hosting nuclear facilities and municipalities participating in feasibility studies as well as many authorities. The comments of the reviewing bodies mainly focused on the decision-making process, including issues relating to method selection and site selection and, in particular, on the selection of sites for site investigation. Several reviewing bodies, particularly universities and institutes of technology, have also submitted comments of a more technical-scientific nature. SKI's evaluation has focused on determining whether SKB's programme can be considered to fulfil the requirements stipulated in the Act on Nuclear Activities that such a programme should be able to result in the implementation of solutions for the final disposal of the spent nuclear fuel from the Swedish nuclear power programme. Furthermore, SKI's evaluation has also focused on the conditions that SKI considers should apply to SKB's future work. Specific comments are made for the following areas: Decision-making process, Method selection and system analysis, Siting, Technical development, Safety assessments

A summary of INSITE activities in tracking SKB's spent fuel repository site investigations from 2002-2009 and of advice provided to the regulatory authorities on the status of site understanding at the end of the surface-based investigations

International Nuclear Information System (INIS)

Chapman, Neil; Bath, Adrian; Geier, Joel; Ove Stephansson; Tiren, Sven; Tsang, Chin-Fu

2010-11-01

SSM and its predecessor SKI employed a team of earth scientists who followed and reviewed SKB's investigations of the potential spent nuclear fuel repository sites at Forsmark and Laxemar. This group was named INSITE (INdependent Site Investigation Tracking and Evaluation) and began its work in 2002 and completed its task with the review of the final versions SKB's site descriptive models, SDM-Site, in 2009. This report is a summary of INSITE's work over the eight-and-a-half year period of the site investigations and the lead-in and the wind-down to the work. It is intended to provide an outline and a record of how INSITE has worked and how its advice was generated and provided to SKI and, latterly, to SSM. Together with all the other documentation generated by INSITE, this report is intended to support the regulatory review of SKB's licence application for a spent nuclear fuel repository

Decoder calibration with ultra small current sample set for intracortical brain-machine interface

Science.gov (United States)

Zhang, Peng; Ma, Xuan; Chen, Luyao; Zhou, Jin; Wang, Changyong; Li, Wei; He, Jiping

2018-04-01

Objective. Intracortical brain-machine interfaces (iBMIs) aim to restore efficient communication and movement ability for paralyzed patients. However, frequent recalibration is required for consistency and reliability, and every recalibration will require relatively large most current sample set. The aim in this study is to develop an effective decoder calibration method that can achieve good performance while minimizing recalibration time. Approach. Two rhesus macaques implanted with intracortical microelectrode arrays were trained separately on movement and sensory paradigm. Neural signals were recorded to decode reaching positions or grasping postures. A novel principal component analysis-based domain adaptation (PDA) method was proposed to recalibrate the decoder with only ultra small current sample set by taking advantage of large historical data, and the decoding performance was compared with other three calibration methods for evaluation. Main results. The PDA method closed the gap between historical and current data effectively, and made it possible to take advantage of large historical data for decoder recalibration in current data decoding. Using only ultra small current sample set (five trials of each category), the decoder calibrated using the PDA method could achieve much better and more robust performance in all sessions than using other three calibration methods in both monkeys. Significance. (1) By this study, transfer learning theory was brought into iBMIs decoder calibration for the first time. (2) Different from most transfer learning studies, the target data in this study were ultra small sample set and were transferred to the source data. (3) By taking advantage of historical data, the PDA method was demonstrated to be effective in reducing recalibration time for both movement paradigm and sensory paradigm, indicating a viable generalization. By reducing the demand for large current training data, this new method may facilitate the application

Colloids or artefacts? A TVO/SKB cooperation project in Olkiluoto, Finland

International Nuclear Information System (INIS)

Laaksoharju, M.; Vuorinen, U.; Snellman, M.; Helenius, J.; Allard, B.; Pettersson, C.; Hinkkanen, H.

1993-12-01

TVO (Teollisuuden Voima Oy, Finland) initiated a co-operative task with SKB (Swedish Nuclear Fuel and Waste Management Co.) to critically evaluate colloid sampling methods at the test site in Olkiluoto, SW Finland. Three different colloid sampling methods were compared when sampling borehole OL-KR1 at 613-618 m depth. One possible way to make a conservative in-situ colloid estimation is to omit the contribution from calcite precipitation which is considered to be the main artefact. When this is made the inorganic colloid content (size 1-1000 nm) in Olkiluoto is 184 ±177 ppb consisting of clay minerals, silica, pyrite, goethite and magnesium oxide; the concentration of organic substances are around 100 ppb. The in-situ colloid concentration seems to be low which is in good agreement with experiences from years of sampling in similar environment and depths. The exercise shows the many difficulties encountered when sampling colloids. Small error in the planning, pump rate selection, a lack of precautionary measures, artefact sensitivity of the method etc have a tendency to affect significantly the results on the measured ppb colliod level

[The current state of the brain-computer interface problem].

Science.gov (United States)

Shurkhay, V A; Aleksandrova, E V; Potapov, A A; Goryainov, S A

2015-01-01

It was only 40 years ago that the first PC appeared. Over this period, rather short in historical terms, we have witnessed the revolutionary changes in lives of individuals and the entire society. Computer technologies are tightly connected with any field, either directly or indirectly. We can currently claim that computers are manifold superior to a human mind in terms of a number of parameters; however, machines lack the key feature: they are incapable of independent thinking (like a human). However, the key to successful development of humankind is collaboration between the brain and the computer rather than competition. Such collaboration when a computer broadens, supplements, or replaces some brain functions is known as the brain-computer interface. Our review focuses on real-life implementation of this collaboration.

A summary of INSITE activities in tracking SKB's spent fuel repository site investigations from 2002-2009 and of advice provided to the regulatory authorities on the status of site understanding at the end of the surface-based investigations

Energy Technology Data Exchange (ETDEWEB)

Chapman, Neil (Chapman Consulting (Switzerland)); Bath, Adrian (Intellisci Ltd, (United Kingdom)); Geier, Joel (Clearwater Hardrock Consulting (United States)); Ove Stephansson (Steph Rock Consulting AB (Sweden)); Tiren, Sven (Geosigma (Sweden)); Tsang, Chin-Fu (Berkeley Geohydrophysics SP (United States))

2010-11-15

SSM and its predecessor SKI employed a team of earth scientists who followed and reviewed SKB's investigations of the potential spent nuclear fuel repository sites at Forsmark and Laxemar. This group was named INSITE (INdependent Site Investigation Tracking and Evaluation) and began its work in 2002 and completed its task with the review of the final versions SKB's site descriptive models, SDM-Site, in 2009. This report is a summary of INSITE's work over the eight-and-a-half year period of the site investigations and the lead-in and the wind-down to the work. It is intended to provide an outline and a record of how INSITE has worked and how its advice was generated and provided to SKI and, latterly, to SSM. Together with all the other documentation generated by INSITE, this report is intended to support the regulatory review of SKB's licence application for a spent nuclear fuel repository

Comments on 'SKB RD and D-Programme 98'. Focused on canister integrity and corrosion

Energy Technology Data Exchange (ETDEWEB)

Bowyer, W.H. [Meadow End Farm, Farnham (United Kingdom); Hermansson, H.P. [Studsvik Material AB, Nykoeping (Sweden)

1999-04-01

According to the Act on Nuclear Activities the nuclear utilities are requested to submit a comprehensive programme for research and development every third year, aiming at the safe storage of radioactive waste produced by the nuclear power plants. The latest was published by SKB in September 1998 and is called the 'RDandD Programme 98'. The work presented in the present report was commissioned by SKI and is a result of reading the 'RDandD Programme 98' and related reports with focus on canister production, integrity and corrosion. We find that those parts of the programme often are difficult to follow owing to the lack of detail in the Programme and in one of the supporting reports. In our opinion this will make the work difficult to monitor by SKI and SKB. We also feel that the interpretation of information already available often is overoptimistic. As a consequence the difficulties ahead are understated and the programme is allowed to converge too quickly. We agree that the materials choices for both the inner and outer canisters are appropriate providing they both can be produced commercially and in a satisfactory metallurgical condition, that they can be quality assured and that no further unforeseen difficulties arise. We also agree that alternative technologies merit consideration for production of the outer canister and that alternative joining processes should be studied. We are actually concerned that greater prominence is not given to the alternatives in the programme. We believe that it should be possible to develop a satisfactory canister for disposal of high level nuclear waste according to the general method proposed by SKB and with the proposed capacity within the time-scale of the overall programme. We do not believe, however, that all the difficulties have been recognised. As a consequence of this the results to date are interpreted optimistically. We believe that progress should be subjected to more professional review within

Resistive switching near electrode interfaces: Estimations by a current model

Science.gov (United States)

Schroeder, Herbert; Zurhelle, Alexander; Stemmer, Stefanie; Marchewka, Astrid; Waser, Rainer

2013-02-01

The growing resistive switching database is accompanied by many detailed mechanisms which often are pure hypotheses. Some of these suggested models can be verified by checking their predictions with the benchmarks of future memory cells. The valence change memory model assumes that the different resistances in ON and OFF states are made by changing the defect density profiles in a sheet near one working electrode during switching. The resulting different READ current densities in ON and OFF states were calculated by using an appropriate simulation model with variation of several important defect and material parameters of the metal/insulator (oxide)/metal thin film stack such as defect density and its profile change in density and thickness, height of the interface barrier, dielectric permittivity, applied voltage. The results were compared to the benchmarks and some memory windows of the varied parameters can be defined: The required ON state READ current density of 105 A/cm2 can only be achieved for barriers smaller than 0.7 eV and defect densities larger than 3 × 1020 cm-3. The required current ratio between ON and OFF states of at least 10 requests defect density reduction of approximately an order of magnitude in a sheet of several nanometers near the working electrode.

SKI`s Evaluation of SKB`s RD and D Programme 95. Review Report

Energy Technology Data Exchange (ETDEWEB)

NONE

1996-10-01

SKI (the Swedish Nuclear Power Inspectorate) has sent SKB`s (the Swedish Nuclear Fuel and Waste Management Co.) RD and D Programme 95 to sixty authorities and organizations for review. 35 reviewing bodies have replied. In various ways, most of the comments are related to the decision-making process, both with regard to site selection and choice of method and only a small number of reviewing bodies have dealt with the more purely technical issues such as the function of the barriers and the safety assessment methodology. SKI`s review of the programme is based on the premises of establishing whether and how the programme can fulfill its actual purpose to identify and implement solutions for the final disposal of the spent nuclear fuel from the Swedish nuclear power plants. SKI`s statement to the Government includes a `Summary and Conclusions` of the `Review Report`. In (the present) `Review Report` SKI reviews the programme and deals with comments from the other reviewing bodies. Furthermore, SKI has commissioned a separate report with the `Comments of the Reviewing Bodies`. 32 refs.

Analysis of Critical Issues in Biosphere Assessment Modelling and Site Investigation

Energy Technology Data Exchange (ETDEWEB)

Egan, M.J.; Thorne, M.C.; Little, R.H.; Pasco, R.F. [Quintessa Limited, Henley-on-Thames (United Kingdom)

2003-07-01

The aim of this document is to present a critical review of issues concerned with the treatment of the biosphere and geosphere-biosphere interface in long-term performance assessment studies for nuclear waste disposal in Sweden. The review covers three main areas of investigation: a review of SKB's plans for undertaking site investigations at candidate locations for the development of a deep geological repository for spent fuel; identification of critical uncertainties associated with SKB's treatment of the geosphere-biosphere interface in recent performance assessments; and a preliminary modelling investigation of the significance of features, events and processes in the near-surface environment in terms of their effect on the accumulation and redistribution of radionuclides at the geosphere-biosphere interface. Overall, SKB's proposals for site investigations are considered to be comprehensive and, if they can be carried out to the specification presented, will constitute a benchmark that other waste management organisations will have to work hard to emulate. The main concern is that expertise for undertaking the investigations and reporting the results could be stretched very thin. The authors have also identified weaknesses in the documentation concerning the collection of evidence for environmental change and on developing scenarios for future environmental change. A fundamental assumption adopted in the renewed assessment of the SFR 1 repository, which is not discussed or justified in any of the documentation that has been reviewed, is that radionuclides enter the water column of the coastal and lake models directly, without passing first through the bed sediments. The modelling study reported herein suggests that SKB's models are robust to range of alternative conceptual descriptions relating to the geosphere-biosphere interface. There are however situations, in which contaminated groundwater is released via sediment rather than directly

Analysis of Critical Issues in Biosphere Assessment Modelling and Site Investigation

International Nuclear Information System (INIS)

Egan, M.J.; Thorne, M.C.; Little, R.H.; Pasco, R.F.

2003-07-01

The aim of this document is to present a critical review of issues concerned with the treatment of the biosphere and geosphere-biosphere interface in long-term performance assessment studies for nuclear waste disposal in Sweden. The review covers three main areas of investigation: a review of SKB's plans for undertaking site investigations at candidate locations for the development of a deep geological repository for spent fuel; identification of critical uncertainties associated with SKB's treatment of the geosphere-biosphere interface in recent performance assessments; and a preliminary modelling investigation of the significance of features, events and processes in the near-surface environment in terms of their effect on the accumulation and redistribution of radionuclides at the geosphere-biosphere interface. Overall, SKB's proposals for site investigations are considered to be comprehensive and, if they can be carried out to the specification presented, will constitute a benchmark that other waste management organisations will have to work hard to emulate. The main concern is that expertise for undertaking the investigations and reporting the results could be stretched very thin. The authors have also identified weaknesses in the documentation concerning the collection of evidence for environmental change and on developing scenarios for future environmental change. A fundamental assumption adopted in the renewed assessment of the SFR 1 repository, which is not discussed or justified in any of the documentation that has been reviewed, is that radionuclides enter the water column of the coastal and lake models directly, without passing first through the bed sediments. The modelling study reported herein suggests that SKB's models are robust to range of alternative conceptual descriptions relating to the geosphere-biosphere interface. There are however situations, in which contaminated groundwater is released via sediment rather than directly to the water column

Autonomous control of inverter-interfaced Distributed Generation units for harmonic current filtering and resonance damping in an islanded microgrid

DEFF Research Database (Denmark)

Wang, Xiongfei; Blaabjerg, Frede; Chen, Zhe

2012-01-01

Harmonic current filtering and resonance damping have become important concerns on the control of an islanded microgrids. To address these challenges, this paper proposes a control method of inverter-interfaced Distributed Generation (DG) units, which can autonomously share harmonic currents and ...

The Swedish Nuclear Power Inspectorate`s evaluation of SKB`s RD and D Program 98. Summary and conclusions

Energy Technology Data Exchange (ETDEWEB)

NONE

1999-04-01

Compared to previous programmes, RD and D Programme 98 is focused to a greater extent on method and site selection and on issues relating to the decision-making process. This is natural, since the programme is now approaching the stage where vital decisions will have to be made. The RD and D Programme 98 report is supplemented by a background report `Detailed Programme for Research and Development 1999-2004` as well as a number of main references `System Reporting`, `Alternative methods`, `Criteria for Site Evaluation` and the `North-South/Coast-Interior` report. In addition, a number of references are available in the form of county-specific general siting studies, feasibility studies etc. SKI has distributed RD and D Programme 98 to sixty-three reviewing bodies for comment. The reviewing bodies include universities and institutes of technology, local safety committees, municipalities hosting nuclear facilities and municipalities participating in feasibility studies as well as many authorities. The comments of the reviewing bodies mainly focused on the decision-making process, including issues relating to method selection and site selection and, in particular, on the selection of sites for site investigation. Several reviewing bodies, particularly universities and institutes of technology, have also submitted comments of a more technical-scientific nature. SKI`s evaluation has focused on determining whether SKB`s programme can be considered to fulfil the requirements stipulated in the Act on Nuclear Activities that such a programme should be able to result in the implementation of solutions for the final disposal of the spent nuclear fuel from the Swedish nuclear power programme. Furthermore, SKI`s evaluation has also focused on the conditions that SKI considers should apply to SKB`s future work. Specific comments are made for the following areas: Decision-making process, Method selection and system analysis, Siting, Technical development, Safety assessments

A lattice-gas model of the ion current across the solid interface: fast-ion conductor - intercalate

International Nuclear Information System (INIS)

Nachev, I.; Balkanski, M.

1994-12-01

The transport of Lithium ions across the material interface: fast-ion conducting glass - intercalate is simulated by a non-trivial lattice-gas model. The model takes explicitly into account the influence of the Coulomb correlations, the site-blocking effect and the boundary conditions on the ion kinetics. Potential device applications of the model are pointed out by computing the current density of Lithium ions for material parameters of the real interface: doped ternary borate glass - Indium Selenide, which constitute the electrolyte and the cathode, respectively, of a thin-film microbattery with improved performance. (author). 10 refs, 4 figs

Current Harmonics Compensation in Microgrids Exploiting the Power Electronics Interfaces of Renewable Energy Sources

Directory of Open Access Journals (Sweden)

Ioannis Bouloumpasis

2015-03-01

Full Text Available This work presents a method of current harmonic reduction in a distorted distribution system. In order to evaluate the proposed method a grid with high-order current harmonics is assumed. The reduction of current distortion is feasible due to the pulse modulation of an active filter, which consists of a buck-boost converter connected back-to-back to a polarity swapping inverter. For a practical application, this system would be the power electronic interface of a Renewable Energy Source (RES and therefore it changes a source of harmonics to a damping harmonics system. Using the proposed method, the current Total Harmonic Distortion (THD of the grid is reduced below the acceptable limits and thus the general power quality of the system is improved. Simulations in the MATLAB/SIMULINK platform and experiments have been performed in order to verify the effectiveness of the proposed method.

Brain-computer interface training combined with transcranial direct current stimulation in patients with chronic severe hemiparesis: Proof of concept study.

Science.gov (United States)

Kasashima-Shindo, Yuko; Fujiwara, Toshiyuki; Ushiba, Junichi; Matsushika, Yayoi; Kamatani, Daiki; Oto, Misa; Ono, Takashi; Nishimoto, Atsuko; Shindo, Keiichiro; Kawakami, Michiyuki; Tsuji, Tetsuya; Liu, Meigen

2015-04-01

Brain-computer interface technology has been applied to stroke patients to improve their motor function. Event-related desynchronization during motor imagery, which is used as a brain-computer interface trigger, is sometimes difficult to detect in stroke patients. Anodal transcranial direct current stimulation (tDCS) is known to increase event-related desynchronization. This study investigated the adjunctive effect of anodal tDCS for brain-computer interface training in patients with severe hemiparesis. Eighteen patients with chronic stroke. A non-randomized controlled study. Subjects were divided between a brain-computer interface group and a tDCS- brain-computer interface group and participated in a 10-day brain-computer interface training. Event-related desynchronization was detected in the affected hemisphere during motor imagery of the affected fingers. The tDCS-brain-computer interface group received anodal tDCS before brain-computer interface training. Event-related desynchronization was evaluated before and after the intervention. The Fugl-Meyer Assessment upper extremity motor score (FM-U) was assessed before, immediately after, and 3 months after, the intervention. Event-related desynchronization was significantly increased in the tDCS- brain-computer interface group. The FM-U was significantly increased in both groups. The FM-U improvement was maintained at 3 months in the tDCS-brain-computer interface group. Anodal tDCS can be a conditioning tool for brain-computer interface training in patients with severe hemiparetic stroke.

The role of bulk and interface states on performance of a-Si: H p-i-n solar cells using reverse current-voltage technique

International Nuclear Information System (INIS)

Mahmood, S A; Kabir, M Z; Murthy, R V R; Dutta, V

2009-01-01

The defect state densities in the bulk of the i-layer and at the p/i interface have been studied in hydrogenated amorphous silicon (a-Si : H) solar cells using reverse current-voltage (J-V) measurements. In this work the cells have been soaked with blue and red lights prior to measurements. The voltage-dependent reverse current has been analysed on the basis of thermal generation of the carriers from midgap states in the i-layer and the carrier injection through the p/i interface. Based on the reverse current behaviour, it has been analysed that at lower reverse bias (reverse voltage, V r r ∼ 25 V) the defect states at the p/i interface are contributing to the reverse currents. The applied reverse bias annealing (RBA) treatment on these cells shows more significant annihilation of defect states at the p/i interface as compared with the bulk of the i-layer. An analytical model is developed to explain the observed behaviour. There is good agreement between the theory and the experimental observations. The fitted defect state densities are 9.1 x 10 15 cm -3 and 8 x 10 18 cm -3 in the bulk of the i-layer and near the p/i interface, respectively. These values decrease to 2.5 x 10 15 cm -3 and 6 x 10 17 cm -3 , respectively, in the samples annealed under reverse bias at 2 V.

Mechanical failure of SKB spent fuel disposal canisters. Mathematical modelling and scoping calculations

International Nuclear Information System (INIS)

Takase, Hiroyasu; Benbow, S.; Grindrod, P.

1998-10-01

According to the current design of SKB, a copper overpack with a cast steel inner component will be used as the disposal canister for spent nuclear fuel. A recent study considered the case of a breach in the copper overpack, through which groundwater could enter the canister. It has pointed out that hydrogen gas generated by an anaerobic corrosion could cushion the system and reduce or eventually stop further infiltration of water into the breached canister, and thence the spent fuel. One potential pitfall in this previous study lies in the fact that it did not consider any processes which might violate the following assumptions which are essential for the gas 'cushioning': 1. Hydrogen gas accumulated in the annular gap in the canister forms a free gas phase which is stable indefinitely into future; 2. Elevated gas pressure in the canister prevents further supply of groundwater except for diffusion of vapour. In the current study we developed a set of mathematical models for the above problem and applied it to carry out an independent assessment of the long-term behaviour of the canister. A key aim in this study was to clarify whether there are any alternative processes which may affect the result obtained by the previous study by violating one of the assumptions listed above. For this purpose, a scenario development exercise was conducted. The result supported the concept described in the previous study. One exception is that possible intrusion of bentonite gel followed by its desaturation could leave paths both for the gas and water simultaneously without forming a gas cushion. This is summarised in the first part of the report. In the second part, development of mathematical models and their applications are described. The key results are: 1. The model describing behaviour of gas and pore water in the canister and the buffer material reproduced the main results of the previous study; 2. The model considering intrusion of the bentonite gel pointed out possibility

Fluctuation in Interface and Electronic Structure of Single-Molecule Junctions Investigated by Current versus Bias Voltage Characteristics.

Science.gov (United States)

Isshiki, Yuji; Fujii, Shintaro; Nishino, Tomoaki; Kiguchi, Manabu

2018-03-14

Structural and electronic detail at the metal-molecule interface has a significant impact on the charge transport across the molecular junctions, but its precise understanding and control still remain elusive. On the single-molecule scale, the metal-molecule interface structures and relevant charge transport properties are subject to fluctuation, which contain the fundamental science of single-molecule transport and implication for manipulability of the transport properties in electronic devices. Here, we present a comprehensive approach to investigate the fluctuation in the metal-molecule interface in single-molecule junctions, based on current-voltage ( I- V) measurements in combination with first-principles simulation. Contrary to conventional molecular conductance studies, this I- V approach provides a correlated statistical description of both the degree of electronic coupling across the metal-molecule interface and the molecular orbital energy level. This statistical approach was employed to study fluctuation in single-molecule junctions of 1,4-butanediamine (DAB), pyrazine (PY), 4,4'-bipyridine (BPY), and fullerene (C 60 ). We demonstrate that molecular-dependent fluctuation of σ-, π-, and π-plane-type interfaces can be captured by analyzing the molecular orbital (MO) energy level under mechanical perturbation. While the MO level of DAB with the σ-type interface shows weak distance dependence and fluctuation, the MO level of PY, BPY, and C 60 features unique distance dependence and molecular-dependent fluctuation against the mechanical perturbation. The MO level of PY and BPY with the σ+π-type interface increases with the increase in the stretch distance. In contrast, the MO level of C 60 with the π-plane-type interface decreases with the increase in the stretching perturbation. This study provides an approach to resolve the structural and electronic fluctuation in the single-molecule junctions and insight into the molecular-dependent fluctuation in

Generation of complex motor patterns in american grasshopper via current-controlled thoracic electrical interfacing.

Science.gov (United States)

Giampalmo, Susan L; Absher, Benjamin F; Bourne, W Tucker; Steves, Lida E; Vodenski, Vassil V; O'Donnell, Peter M; Erickson, Jonathan C

2011-01-01

Micro-air vehicles (MAVs) have attracted attention for their potential application to military applications, environmental sensing, and search and rescue missions. While progress is being made toward fabrication of a completely human-engineered MAV, another promising approach seeks to interface to, and take control of, an insect's nervous system. Cyborg insects take advantage of their innate exquisite loco-motor, navigation, and sensing abilities. Recently, several groups have demonstrated the feasibility of radio-controlled flight in the hawkmoth and beetle via electrical neural interfaces. Here, we report a method for eliciting the "jump" response in the American grasshopper (S. Americana). We found that stimulating the metathoracic T3 ganglion with constant-current square wave pulses with amplitude 186 ± 40 μA and frequency 190 ± 13 Hz reproducibly evoked (≥95% success rate) the desired motor activity in N=3 test subjects. To the best of our knowledge, this is the first report of an insect cyborg with a synchronous neuromuscular system.

Amplifier spurious input current components in electrode-electrolyte interface impedance measurements

Directory of Open Access Journals (Sweden)

Madrid Rossana E

2005-03-01

Full Text Available Abstract Background In Impedance Microbiology, the time during which the measuring equipment is connected to the bipolar cells is rather long, usually between 6 to 24 hrs for microorganisms with duplication times in the order of less than one hour and concentrations ranging from 101 to 107 [CFU/ml]. Under these conditions, the electrode-electrolyte interface impedance may show a slow drift of about 2%/hr. By and large, growth curves superimposed on such drift do not stabilize, are less reproducible, and keep on distorting all over the measurement of the temporal reactive or resistive records due to interface changes, in turn originated in bacterial activity. This problem has been found when growth curves were obtained by means of impedance analyzers or with impedance bridges using different types of operational amplifiers. Methods Suspecting that the input circuitry was the culprit of the deleterious effect, we used for that matter (a ultra-low bias current amplifiers, (b isolating relays for the selection of cells, and (c a shorter connection time, so that the relays were maintained opened after the readings, to bring down such spurious drift to a negligible value. Bacterial growth curves were obtained in order to test their quality. Results It was demonstrated that the drift decreases ten fold when the circuit remained connected to the cell for a short time between measurements, so that the distortion became truly negligible. Improvement due to better-input amplifiers was not as good as by reducing the connection time. Moreover, temperature effects were insignificant with a regulation of ± 0.2 [°C]. Frequency did not influence either. Conclusion The drift originated either at the dc input bias offset current (Ios of the integrated circuits, or in discrete transistors connected directly to the electrodes immersed in the cells, depending on the particular circuit arrangement. Reduction of the connection time was the best countermeasure.

Current at Metal-Organic Interfaces

Science.gov (United States)

Kern, Klaus

2012-02-01

Charge transport through atomic and molecular constrictions greatly affects the operation and performance of organic electronic devices. Much of our understanding of the charge injection and extraction processes in these systems relays on our knowledge of the electronic structure at the metal-organic interface. Despite significant experimental and theoretical advances in studying charge transport in nanoscale junctions, a microscopic understanding at the single atom/molecule level is missing. In the present talk I will present our recent results to probe directly the nanocontact between single molecules and a metal electrode using scanning probe microscopy and spectroscopy. The experiments provide unprecedented microscopic details of single molecule and atom junctions and open new avenues to study quantum critical and many body phenomena at the atomic scale. Implications for energy conversion devices and carbon based nanoelectronics will also be discussed.

P300 brain computer interface: current challenges and emerging trends

Science.gov (United States)

Fazel-Rezai, Reza; Allison, Brendan Z.; Guger, Christoph; Sellers, Eric W.; Kleih, Sonja C.; Kübler, Andrea

2012-01-01

A brain-computer interface (BCI) enables communication without movement based on brain signals measured with electroencephalography (EEG). BCIs usually rely on one of three types of signals: the P300 and other components of the event-related potential (ERP), steady state visual evoked potential (SSVEP), or event related desynchronization (ERD). Although P300 BCIs were introduced over twenty years ago, the past few years have seen a strong increase in P300 BCI research. This closed-loop BCI approach relies on the P300 and other components of the ERP, based on an oddball paradigm presented to the subject. In this paper, we overview the current status of P300 BCI technology, and then discuss new directions: paradigms for eliciting P300s; signal processing methods; applications; and hybrid BCIs. We conclude that P300 BCIs are quite promising, as several emerging directions have not yet been fully explored and could lead to improvements in bit rate, reliability, usability, and flexibility. PMID:22822397

Evaluation of SKB's report 'Deep repository for spent nuclear fuel: SR 97 - Post-closure safety', Focusing on the assessment of transport processes in the geosphere

International Nuclear Information System (INIS)

Woerman, A.; Shulan Xu

2000-01-01

This report describes a critical review of the safety assessment performed on the final repository for nuclear waste in Sweden that is proposed by SKB in 'Deep Repository for Spent Nuclear Fuel: SR 97 - Post-closure Safety'. The review was requested by the Swedish Nuclear Power Inspectorate (SKI). The waste repository consists of several barriers that work together with the purpose of delaying radionuclide migration and reducing the activity that eventually affects the biosphere. A main criticism is the lack of a formal risk analysis and uncertainties in several analyses that make it difficult to comprehend the overall risk of the repository. A formal risk analysis should comprise a probabilistic treatment of all components included in the system. This is not the case in the SKB's report since the probabilistic analyses are limited only to certain aspects. The use of conservative model parameters are not a substitute for risk analysis nor can they compensate for possible model biases. Bias can be expected in most of the existing models of radionuclide migration in fractured bedrock. SKB should present a clear comparison on the importance of the different barrier components (uranium-dioxide matrix, copper canister, buffer and bedrock) on the retardation of radionuclides. It is unclear as to what extent the capacity of the bedrock to retain migrating radionuclides is critical to the capacity of the repository. A large part of the SR 97 report is focused on retardation processes in bedrock and a reader can interpret this as the technical weight given on retardation in the bedrock. However, with the present state of knowledge, it is our opinion that we cannot with an acceptable degree of accuracy predict the radionuclide transport in bedrock or quantify risk levels associated with radioactivity in the biosphere. There are large uncertainties concerning the way by which sorption processes should be formulated and the impact of colloids on the transport that can be

Effect of Alternating Current on the Cathodic Protection and Interface Structure of X80 Steel

Directory of Open Access Journals (Sweden)

Huiru Wang

2017-07-01

Full Text Available This study employs potential-monitoring techniques, cyclic voltammetry tests, alternating current (AC voltammetry methods, and surface characterization to investigate the AC corrosion of cathodically protected X80 pipeline steel. In a non-passive neutral solution at pH 7.2, a sufficiently negative potential completely protects steel at an AC current density of 100 A/m2. In an alkaline solution at pH 9.6, more serious AC corrosion occurs at more negative cathodic protection (CP potential, whereas without CP the steel suffers negligible corrosion. In addition, the interface capacitance increases with AC amplitude. Based on these results, the AC corrosion mechanisms that function under various conditions are analyzed and described.

Interface stability of granular filter structures under currents

NARCIS (Netherlands)

Verheij, H.J.; Hoffmans, G.; Dorst, K.; Van de Sande, S.

2012-01-01

Granular filters are used for protection of structures against scour and erosion. For a proper functioning it is necessary that the interfaces between the filter structure, the subsoil and the water flowing above the filter structure are stable. Stability means that there is no transport of subsoil

Review of results from SKB R and D on grouting technology for sealing the rock, years 1996-2000; Oeversikt av resuItat fraan SKB:s FoU inom injekteringsteknik foer bergtaetning aaren 1996-2000

Energy Technology Data Exchange (ETDEWEB)

Boden, A. (ed.) [Swedpower AB, Stockholm (Sweden); Eklund, D. [Vattenfall Utveckling AB, Aelvkarleby (Sweden); Eriksson, Magnus [Royal Inst. of Technology, Stockholm (Sweden). Div. Soil and Rock Mechanics; Fransson, Aasa [Chalmers Univ. of Technology, Goeteborg (Sweden). Inst. of Geology; Hansson, Paer [Vattenfall Utveckling AB, Aelvkarleby (Sweden); Lagerblad, B. [Swedish Cement and Concrete Research Inst., Stockholm (Sweden); Lindblom, U. [Chalmers Univ. of Technology, Goeteborg (Sweden). Dept. of Geotechnical Engineering; Wilen, P. [Swedpower AB, Goeteborg (Sweden)

2001-05-01

In order identify the current state of the art and developments needs, SKB assembled a group of experts from universities and other research organisations. Internal plans were written for the subprojects 'Characterisation of rock for grouting purposes', 'Mechanisms that control the spreading of grout in jointed rock' and 'Cement based grouting material'. Later internal plans for the subprojects 'Demands on grouting' and 'Stabilising and sealing effect of pre-grouting' were written. The aims, which were set for the different subprojects, were in short, to summarise the technological advances, establish a method for rock characterisation from a grouting point of view, develop conceptual and numerical models for simulation of the grouting course, characterise grout in a relevant way, develop understanding and theoretical know-how of durability and chemical influence, identify and develop a number of grouting materials for different situations, develop a specification of requirements for grouting and to verify the theories in laboratory. In the subproject 'Demands on grouting' a literature review was carried out. One important conclusion from the study is that the concept is not very well dealt with in the literature. SKB are currently investigating the prerequisites for the construction of the deep repository. One part of that work is to further specify demands on maximum allowed volume of leakage water for the repository as a whole and also for each part of the deep repository. In the subproject 'Characterisation of rock for grouting purposes', the possibilities of using hydraulic tests for predictions and design have been studied. The idea of this study was to investigate correspondences and deviations to increase the understanding of what is measured in a water-loss measurement. One can draw the conclusion that hydraulic tests are useful when describing the fracture geometry. Numerical modelling

User interface support

Science.gov (United States)

Lewis, Clayton; Wilde, Nick

1989-01-01

Space construction will require heavy investment in the development of a wide variety of user interfaces for the computer-based tools that will be involved at every stage of construction operations. Using today's technology, user interface development is very expensive for two reasons: (1) specialized and scarce programming skills are required to implement the necessary graphical representations and complex control regimes for high-quality interfaces; (2) iteration on prototypes is required to meet user and task requirements, since these are difficult to anticipate with current (and foreseeable) design knowledge. We are attacking this problem by building a user interface development tool based on extensions to the spreadsheet model of computation. The tool provides high-level support for graphical user interfaces and permits dynamic modification of interfaces, without requiring conventional programming concepts and skills.

Automating the production of high-purity zirconium from waste products in industrial furnaces SKB-5025 and apparatuses TS-40M

International Nuclear Information System (INIS)

Lavrikov, S.A.; Kotsar', M.L.; Lapidus, A.O.; Akhtonov, S.G.; Aleksandrov, A.V.; Ogorodnikov, L.V.; Chernyshev, A.A.; Kopysov, N.V.

2014-01-01

A disadvantage of iodide refining of zirconium in industrial furnaces in the processing of waste products production in JSC CMP is the low direct yield of the metal in iodide rods and large energy consumption of the process. The aim of this work is to optimize the process by means of automated control. The paper deals with the creation of a test unit to automate the iodide refining of zirconium in JSC CMP. The main features of the unit, the hardware and software of the automated unit and the results of its work during the operation are described. A scheme for the automation of 10 furnaces SKB-5025 by optimizing the total cost of computing equipment and for software improvements was proposed and implemented in 2012

Complex Interfaces Under Change

DEFF Research Database (Denmark)

Rosbjerg, Dan

The hydrosphere is dynamic across the major compartments of the Earth system: the atmosphere, the oceans and seas, the land surface water, and the groundwater within the strata below the two last compartments. The global geography of the hydrosphere essentially depends on thermodynamic and mechan...... these interfaces and interfaced compartments and processes. Climate, sea-level, oceanographic currents and hydrological processes are all affected, while anthropogenic changes are often intense in the geographic settings corresponding to such interfaces....... and mechanical processes that develop within this structure. Water-related processes at the interfaces between the compartments are complex, depending both on the interface itself, and on the characteristics of the interfaced compartments. Various aspects of global change directly or indirectly impact...

The current regulatory requirements on optimisation and BAT in Sweden in the context of geological disposal

International Nuclear Information System (INIS)

Dverstorp, B.

2010-01-01

Bjorn Dverstorp, Swedish Radiation Safety authority (SSM) presented 'The current regulatory requirements on optimisation and BAT in Sweden in the context of geological disposal'. In Sweden, a nuclear waste repository will be evaluated according to both to general environmental legislation (the Environmental Code, SFS, 1998:808) and according to more specific requirements in the Act on Nuclear Activities (SFS, 1984:3) and the Radiation Protection Act (SFS, 1988:220). The evaluations according to these laws will be carried out according to two separate, but coordinated, legal-review and decision-making processes. This will be a basis for the siting process. Although the requirements on BAT and siting in the Environmental Code apply to radiological protection, they aim at a broader system optimisation. The more specific requirements on optimisation and BAT of radiological protection of geological disposal systems are given in the regulations associated with the Radiation Protection Act. The Swedish radiation protection regulations (SSM, 2009) comprise three corner stones: a risk target, environmental protection goals and the use of optimisation and BAT. In SSM' s guidance optimisation is defined as a means to reduce risk, guided by the results of risk calculations. In case of a conflict between BAT and optimisation, measures satisfying BAT should have priority. Application of optimisation and BAT on different timescales are described as well as for human intrusion scenarios. B. Dverstorp explained that because of uncertainties in the long term there is a need for additional arguments in the safety case in support of decision making. It is in this context that the requirements on optimisation and BAT should be seen as supplementary to the risk target, in providing evidence that the developer has taken into consideration, as far as reasonably possible, measures and options for reducing future doses and risks. Both principles focus on the proponent's work on developing

Human-machine interface in mobile teleoperators

International Nuclear Information System (INIS)

Draper, J.V.

1985-01-01

In this document the following point has been made: human-machine interface is not ideal, and may be improved upon: telepresence is ideal but not required; current interfaces degrade normal human inputs/outputs; available and developing technology can improve interfaces

Handling Interfaces and Time-varying Properties in Radionuclide Transport Models

International Nuclear Information System (INIS)

Robinson, Peter; Watson, Claire

2010-12-01

This report documents studies undertaken by Quintessa during 2010 in preparation for the SR-Site review that will be initiated by SSM in 2011. The studies relate to consequence analysis calculations, that is to the calculation of radionuclide release and transport if a canister is breached. A sister report documents modelling work undertaken to investigate the coupled processes relevant to copper corrosion and buffer erosion. The Q eq concept is an important part of SKB's current methodology for radionuclide transport using one-dimensional transport modelling; it is used in particular to model transport at the buffer/fracture interface. Quintessa's QPAC code has been used to investigate the Q eq approach and to explore the importance of heterogeneity in the fracture and spalling on the deposition hole surface. The key conclusions are that: - The basic approach to calculating Q eq values is sound and can be reproduced in QPAC. - The fracture resistance dominates over the diffusive resistance in the buffer except for the highest velocity cases. - Heterogeneity in the fracture, in terms of uncorrelated random variations in the fracture aperture, tends to reduce releases, so the use of a constant average aperture approach is conservative. - Narrow channels could lead to the same release as larger fractures with the same pore velocity, so a channel enhancement factor of √10 should be considered. - A spalling zone that increases the area of contact between flowing water and the buffer has the potential to increase the release significantly and changes the functional dependence of Q eq frac on the flowing velocity. Quintessa's AMBER software has previously been used to reproduce SKB's one-dimensional transport calculations and AMBER allows the use of time varying properties. This capability has been used to investigate the effects of glacial episodes on radionuclide transport. The main parameters that could be affected are sorption coefficients and flow rates. For both

Handling Interfaces and Time-varying Properties in Radionuclide Transport Models

Energy Technology Data Exchange (ETDEWEB)

Robinson, Peter; Watson, Claire (Quintessa Ltd., Henley-on-Thames (United Kingdom))

2010-12-15

This report documents studies undertaken by Quintessa during 2010 in preparation for the SR-Site review that will be initiated by SSM in 2011. The studies relate to consequence analysis calculations, that is to the calculation of radionuclide release and transport if a canister is breached. A sister report documents modelling work undertaken to investigate the coupled processes relevant to copper corrosion and buffer erosion. The Q{sub eq} concept is an important part of SKB's current methodology for radionuclide transport using one-dimensional transport modelling; it is used in particular to model transport at the buffer/fracture interface. Quintessa's QPAC code has been used to investigate the Q{sub eq} approach and to explore the importance of heterogeneity in the fracture and spalling on the deposition hole surface. The key conclusions are that: - The basic approach to calculating Q{sub eq} values is sound and can be reproduced in QPAC. - The fracture resistance dominates over the diffusive resistance in the buffer except for the highest velocity cases. - Heterogeneity in the fracture, in terms of uncorrelated random variations in the fracture aperture, tends to reduce releases, so the use of a constant average aperture approach is conservative. - Narrow channels could lead to the same release as larger fractures with the same pore velocity, so a channel enhancement factor of sq root10 should be considered. - A spalling zone that increases the area of contact between flowing water and the buffer has the potential to increase the release significantly and changes the functional dependence of Q{sub eq}frac on the flowing velocity. Quintessa's AMBER software has previously been used to reproduce SKB's one-dimensional transport calculations and AMBER allows the use of time varying properties. This capability has been used to investigate the effects of glacial episodes on radionuclide transport. The main parameters that could be affected are

Interface, a dispersed architecture

NARCIS (Netherlands)

Vissers, C.A.

1976-01-01

Past and current specification techniques use timing diagrams and written text to describe the phenomenology of an interface. This paper treats an interface as the architecture of a number of processes, which are dispersed over the related system parts and the message path. This approach yields a

Interface Anywhere

Data.gov (United States)

National Aeronautics and Space Administration — Current paradigms for crew interfaces to the systems that require control are constrained by decades old technologies which require the crew to be physically near an...

The effect of heat currents on the stability of the liquid solid interface

International Nuclear Information System (INIS)

Bowley, R.M.; Nozieres, P.

1992-01-01

Rapid changing of the temperature of a liquid in equilibrium with its solid can lead to instabilities of the interface in two ways : the change in pressure, induced by a temperature change at the interface, leads to a uniaxial stress which can cause a Grinfeld instability at the capillary wavelength; a temperature gradient is set up which modifies the effective gravity at the interface. When the effective gravity becomes negative, the interface is unstable at very long wavelengths. For a superfluid, such as 4 He, the situation is more complex. If we ignore surface dissipation, there is still a small critical temperature gradient across the solid above which the interface is unstable. However surface dissipation -in particular the growth resistance- pushes the instability to huge temperature gradients, ones which cannot be realised experimentally. The only instability that can be seen is caused by uniaxial stress

Critical current density of MgB2 thin films and the effect of interface pinning

International Nuclear Information System (INIS)

Choi, Eun-Mi; Gupta, S K; Sen, Shashwati; Lee, Hyun-Sook; Kim, Hyun-Jung; Lee, Sung-Ik

2004-01-01

Preferentially oriented MgB 2 thin films with c-axis normal to the surface have been prepared and characterized for microstructure and transport properties. The magnetic field dependence of superconducting critical current density J c has been determined from the magnetization hysteresis (M-H) loops at various temperatures using the Bean's critical state model. High J c of these films show their potential for applications. We have also measured the angular dependences of J c . The angular dependence is seen to be in agreement with the anisotropic Ginzburg-Landau model except that at angles close to the ab plane, increased pinning due to film-substrate interaction is observed. The angular range where interface pinning is effective has been determined by measurement of asymmetry in dissipation on reversal of current for fields applied at angles close to the ab plane

Interface-Induced Phenomena in Magnetism.

Science.gov (United States)

Hellman, Frances; Hoffmann, Axel; Tserkovnyak, Yaroslav; Beach, Geoffrey S D; Fullerton, Eric E; Leighton, Chris; MacDonald, Allan H; Ralph, Daniel C; Arena, Dario A; Dürr, Hermann A; Fischer, Peter; Grollier, Julie; Heremans, Joseph P; Jungwirth, Tomas; Kimel, Alexey V; Koopmans, Bert; Krivorotov, Ilya N; May, Steven J; Petford-Long, Amanda K; Rondinelli, James M; Samarth, Nitin; Schuller, Ivan K; Slavin, Andrei N; Stiles, Mark D; Tchernyshyov, Oleg; Thiaville, André; Zink, Barry L

2017-01-01

This article reviews static and dynamic interfacial effects in magnetism, focusing on interfacially-driven magnetic effects and phenomena associated with spin-orbit coupling and intrinsic symmetry breaking at interfaces. It provides a historical background and literature survey, but focuses on recent progress, identifying the most exciting new scientific results and pointing to promising future research directions. It starts with an introduction and overview of how basic magnetic properties are affected by interfaces, then turns to a discussion of charge and spin transport through and near interfaces and how these can be used to control the properties of the magnetic layer. Important concepts include spin accumulation, spin currents, spin transfer torque, and spin pumping. An overview is provided to the current state of knowledge and existing review literature on interfacial effects such as exchange bias, exchange spring magnets, spin Hall effect, oxide heterostructures, and topological insulators. The article highlights recent discoveries of interface-induced magnetism and non-collinear spin textures, non-linear dynamics including spin torque transfer and magnetization reversal induced by interfaces, and interfacial effects in ultrafast magnetization processes.

A Review of Models for Dose Assessment Employed by SKB in the Renewed Safety Assessment for SFR 1

Energy Technology Data Exchange (ETDEWEB)

Shaw, George [Imperial College of Science Technology and Medicine (United Kingdom)

2002-09-01

This document provides a critical review, on behalf of SSI, of the models employed by the Swedish Nuclear Fuel and Waste Management Co (SKB) for dose assessment in the renewed safety assessment for the final repository for radioactive operational waste (SFR 1) in Forsmark, Sweden. The main objective of the review is to examine the models used by SKB for radiological dose assessment in a series of evolving biotopes in the vicinity of the Forsmark repository within a time frame beginning in 3000 AD and extending beyond 7500 AD. Five biosphere models (for coasts, lakes, agriculture, mires and wells) are described in Report TR-01-04. The principal consideration of the review is to determine whether these models are fit for the purpose of dose evaluation over the time frames involved and in the evolving sequence of biotopes specified. As well as providing general observations and comments on the modelling approach taken, six specific questions are addressed, as follows. Are the assumptions underlying the models justifiable? Are all reasonably foreseeable environmental processes considered? Has parameter uncertainty been sufficiently and reasonably addressed? Have sufficient models been used to address all reasonably foreseeable biotopes? Are the transitions between biotopes modelled adequately (specifically, are initial conditions for developing biotopes adequately specified by calculations for subsiding biotopes)? Have all critical radionuclides been identified? It is concluded that, in general, the assumptions underlying most of the models are justifiable. The exceptions are a) the rather simplistic approach taken in the Coastal Model and b) the lack of consideration of wild foods and age-dependence when calculating exposures of humans to radionuclides via dietary pathways. Most foreseeable processes appear to have been accounted for within the constraints of the models used, although it is recommended that attention be paid to future climate states when considering

Visualization of the interfacial turbulence associated with remarkable faradaic current amplification at a polarized water/1,2-dichloroethane interface

Czech Academy of Sciences Publication Activity Database

Trojánek, Antonín; Mareček, Vladimír; Samec, Zdeněk

2017-01-01

Roč. 80, JUL 2017 (2017), s. 1-4 ISSN 1388-2481 R&D Projects: GA ČR GA17-09980S Institutional support: RVO:61388955 Keywords : Water/1,2-dichloroethane interface * Ion transfer * Current amplification Subject RIV: CG - Electrochemistry OBOR OECD: Electrochemistry (dry cells, batteries, fuel cells, corrosion metals, electrolysis) Impact factor: 4.396, year: 2016

Natural user interfaces for multitouch devices

OpenAIRE

Bukovinski, Matej

2010-01-01

This thesis presents a new class of user interfaces, which a commonly referred to as natural user interfaces. It discusses their main characteristics, evolution and advantages over currently dominant graphical user interfaces. Special attention is devoted to the subgroup of natural user interfaces for multitouch devices. Multitouch technology is firstly presented from a technical point of view and afterwards also in practice in form of a comparative study of six popular multitouch platfo...

Transient behavior of interface state continuum at InP insulator-semiconductor interface

International Nuclear Information System (INIS)

Hasegawa, H.; Masuda, H.; He, L.; Luo, J.K.; Sawada, T.; Ohno, H.

1987-01-01

To clarify the drain current drift mechanism in InP MISFETs, an isothermal capacitance transient spectroscopy (ICTS) study of the interface state continuum is made on the anodic Al 2 O 3 /native oxide/ InP MIS system. Capture behavior is temperature-independent, non-exponential and extremely slow, whereas emission behavior is temperature- and bias- dependent, and is much faster. The observed behavior is explained quantitatively by the disorder induced gap state (DIGS) model, where states are distributed both in energy and in space. By comparing the transient behavior of interface states with the observed drift behavior of MISFETs, it is concluded that the electron capture by the DIGS continuum is responsible for the drain current drift of MISFETs. This led to a complete computer simulation of the observed current drift behavior

Evaluation of SKB's report 'Deep repository for spent nuclear fuel: SR 97 - Post-closure safety', Focusing on the assessment of transport processes in the geosphere

Energy Technology Data Exchange (ETDEWEB)

Woerman, A.; Shulan Xu [Uppsala Univ. (Sweden). Dept. of Geoscience

2000-12-01

This report describes a critical review of the safety assessment performed on the final repository for nuclear waste in Sweden that is proposed by SKB in 'Deep Repository for Spent Nuclear Fuel: SR 97 - Post-closure Safety'. The review was requested by the Swedish Nuclear Power Inspectorate (SKI). The waste repository consists of several barriers that work together with the purpose of delaying radionuclide migration and reducing the activity that eventually affects the biosphere. A main criticism is the lack of a formal risk analysis and uncertainties in several analyses that make it difficult to comprehend the overall risk of the repository. A formal risk analysis should comprise a probabilistic treatment of all components included in the system. This is not the case in the SKB's report since the probabilistic analyses are limited only to certain aspects. The use of conservative model parameters are not a substitute for risk analysis nor can they compensate for possible model biases. Bias can be expected in most of the existing models of radionuclide migration in fractured bedrock. SKB should present a clear comparison on the importance of the different barrier components (uranium-dioxide matrix, copper canister, buffer and bedrock) on the retardation of radionuclides. It is unclear as to what extent the capacity of the bedrock to retain migrating radionuclides is critical to the capacity of the repository. A large part of the SR 97 report is focused on retardation processes in bedrock and a reader can interpret this as the technical weight given on retardation in the bedrock. However, with the present state of knowledge, it is our opinion that we cannot with an acceptable degree of accuracy predict the radionuclide transport in bedrock or quantify risk levels associated with radioactivity in the biosphere. There are large uncertainties concerning the way by which sorption processes should be formulated and the impact of colloids on the transport

Rock grouting. Current competence and development for the final repository

International Nuclear Information System (INIS)

Emmelin, Ann; Brantberger, Martin; Eriksson, Magnus; Gustafson, Gunnar; St ille, Haakan

2007-06-01

The report aims at presenting the overall state of grouting competence and development relating to the final repository and at motivating and giving detail to the grouting sections presented in the 2007 version of the overall SKB report 'Programme for research, development and demonstration of methods for the management and disposal of nuclear waste' that is presented to the government every three years. The report offers suggestions for principles for planning, design and execution of grouting and describes the further work thought to be necessary in order to meet the requirements of the final repository, that are currently given as working premises. This report does not aim to, and cannot, describe the grouting processes in detail. For details of current concepts, experience and development work, a list of references is provided. In Chapter 2, the task of sealing the underground repository is examined and an overall approach presented. Although the requirements related to this task are preliminary, it is made evident that they concern both the actual grouting results and the process leading to the achievement of these results. Chapter 3 is a conceptual description of grouting and the factors that govern the spreading of grout in the rock mass. It is intended as an introduction to Chapters 4-6, which describe the state of grouting competence and the tools available for the sealing of the final repository facility. Both common practice and cutting-edge research are dealt with in these chapters, mainly relying on references where available. Chapters 4 and 5 focus on the system consisting of the fundamental components the rock mass, the grout materials and the grouting technology, and how these system components interact whilst, in Chapter 6, the rock/grout technical system is viewed in a brief organizational context. Based on the requirements on results and the overall grouting process on the one hand and the current competence in grouting theory and practice on the

Rock grouting. Current competence and development for the final repository

Energy Technology Data Exchange (ETDEWEB)

Emmelin, Ann (Swedish Nuclear Fuel and Waste Management Co., Stockholm (SE)); Brantberger, Martin (Ramboell (SE)); Eriksson, Magnus (Vattenfall Power Consultant (SE)); Gustafson, Gunnar (Chalmers Univ. of Technology, Goeteborg (SE)); Stille, Haakan (Royal Inst. of Technology, Stockholm (SE))

2007-06-15

The report aims at presenting the overall state of grouting competence and development relating to the final repository and at motivating and giving detail to the grouting sections presented in the 2007 version of the overall SKB report 'Programme for research, development and demonstration of methods for the management and disposal of nuclear waste' that is presented to the government every three years. The report offers suggestions for principles for planning, design and execution of grouting and describes the further work thought to be necessary in order to meet the requirements of the final repository, that are currently given as working premises. This report does not aim to, and cannot, describe the grouting processes in detail. For details of current concepts, experience and development work, a list of references is provided. In Chapter 2, the task of sealing the underground repository is examined and an overall approach presented. Although the requirements related to this task are preliminary, it is made evident that they concern both the actual grouting results and the process leading to the achievement of these results. Chapter 3 is a conceptual description of grouting and the factors that govern the spreading of grout in the rock mass. It is intended as an introduction to Chapters 4-6, which describe the state of grouting competence and the tools available for the sealing of the final repository facility. Both common practice and cutting-edge research are dealt with in these chapters, mainly relying on references where available. Chapters 4 and 5 focus on the system consisting of the fundamental components the rock mass, the grout materials and the grouting technology, and how these system components interact whilst, in Chapter 6, the rock/grout technical system is viewed in a brief organizational context. Based on the requirements on results and the overall grouting process on the one hand and the current competence in grouting theory and

Prediction of novel interface-driven spintronic effects

International Nuclear Information System (INIS)

Bhattacharjee, Satadeep; Singh, Surendra; Bellaiche, L; Wang, D; Viret, M

2014-01-01

The recently proposed coupling between the angular momentum density and magnetic moment (Raeliarijaona et al 2013 Phys. Rev. Lett. 110 137205) is shown here to result in the prediction of (i) novel spin currents generated by an electrical current and (ii) new electrical currents induced by a spin current in systems possessing specific interfaces between two different materials. Some of these spin (electrical) currents can be reversed near the interface by reversing the applied electrical (spin) current. Similarities and differences between these novel spintronic effects and the well-known spin Hall and inverse spin Hall effects are also discussed. (paper)

Principle and modelling of Transient Current Technique for interface traps characterization in monolithic pixel detectors obtained by CMOS-compatible wafer bonding

International Nuclear Information System (INIS)

Bronuzzi, J.; Mapelli, A.; Moll, M.; Sallese, J.M.

2016-01-01

In the framework of monolithic silicon radiation detectors, a fabrication process based on a recently developed silicon wafer bonding technique at low temperature was proposed. Ideally, this new process would enable direct bonding of a read-out electronic chip wafer on a highly resistive silicon substrate wafer, which is expected to present many advantages since it would combine high performance IC's with high sensitive ultra-low doped bulk silicon detectors. But electrical properties of the bonded interface are critical for this kind of application since the mobile charges generated by radiation inside the bonded bulk are expected to transit through the interface in order to be collected by the read-out electronics. In this work, we propose to explore and develop a model for the so-called Transient Current Technique (TCT) to identify the presence of deep traps at the bonded interface. For this purpose, we consider a simple PIN diode reversely biased where the ultra-low doped active region of interest is set in full depletion. In a first step, Synopsys Sentaurus TCAD is used to evaluate the soundness of this technique for interface traps characterization such as it may happen in bonded interfaces. Next, an analytical model is developed in details to give a better insight into the physics behind the TCT for interface layers. Further, this can be used as a simple tool to evidence what are the relevant parameters influencing the TCT signal and to set the basis for preliminary characterizations.

Structure and properties of interfaces in ceramics

International Nuclear Information System (INIS)

Bonnell, D.; Ruehle, M.; Chowdhry, U.

1995-01-01

The motivation for the symposium was the observation that interfaces in crystallographically and compositionally complex systems often dictate the performance and reliability of devices that utilize functional ceramics. The current level of understanding of interface-property relations in silicon-based devices required over 30 years of intensive research. Similar issues influence the relationship between atomic bonding at interfaces and properties in functional ceramic systems. The current understanding of these complex interfaces does not allow correlation between atomic structure and interface properties, in spite of their importance to a number of emerging technologies (wireless communications, radar-based positioning systems, sensors, etc.). The objective of this symposium was to focus attention on these fundamental issues by featuring recent theoretical and experimental work from various disciplines that impact the understanding of interface chemistry, structure, and properties. The emphasis was on relating properties of surfaces and interfaces to structure through an understanding of atomic level phenomena. Interfaces of interest include metal/ceramic, ceramic/ceramic, ceramic/vapor, etc., in electronic, magnetic, optical, ferroelectric, piezoelectric, and dielectric applications. Sixty one papers have been processed separately for inclusion on the data base

User interface development

Science.gov (United States)

Aggrawal, Bharat

1994-01-01

This viewgraph presentation describes the development of user interfaces for OS/2 versions of computer codes for the analysis of seals. Current status, new features, work in progress, and future plans are discussed.

Solution of the mathematical adjoint equations for an interface current nodal formulation

International Nuclear Information System (INIS)

Yang, W.S.; Taiwo, T.A.; Khalil, H.

1994-01-01

Two techniques for solving the mathematical adjoint equations of an interface current nodal method are described. These techniques are the ''similarity transformation'' procedure and a direct solution scheme. A theoretical basis is provided for the similarity transformation procedure originally proposed by Lawrence. It is shown that the matrices associated with the mathematical and physical adjoint equations are similar to each other for the flat transverse leakage approximation but not for the quadratic leakage approximation. It is also shown that a good approximate solution of the mathematical adjoint for the quadratic transverse leakage approximation is obtained by applying the similarity transformation for the flat transverse leakage approximation to the physical adjoint solution. The direct solution scheme, which was developed as an alternative to the similarity transformation procedure, yields the correct mathematical adjoint solution for both flat and quadratic transverse leakage approximations. In this scheme, adjoint nodal equations are cast in a form very similar to that of the forward equations by employing a linear transformation of the adjoint partial currents. This enables the use of the forward solution algorithm with only minor modifications for solving the mathematical adjoint equations. By using the direct solution scheme as a reference method, it is shown that while the results computed with the similarity transformation procedure are approximate, they are sufficiently accurate for calculations of global and local reactivity changes resulting from coolant voiding in a liquid-metal reactor

User interface design in safety parameter display systems

International Nuclear Information System (INIS)

Schultz, E.E. Jr.; Johnson, G.L.

1988-01-01

The extensive installation of computerized safety Parameter Display Systems (SPDSs) in nuclear power plants since the Three-Mile Island accident has enhanced plant safety. It has also raised new issues of how best to ensure an effective interface between human operators and the plant via computer systems. New developments in interface technologies since the current generation of SPDSs was installed can contribute to improving display interfaces. These technologies include new input devices, three-dimensional displays, delay indicators, and auditory displays. Examples of how they might be applied to improve current SPDSs are given. These examples illustrate how the new use interface technology could be applied to future nuclear plant displays

Principle and modelling of Transient Current Technique for interface traps characterization in monolithic pixel detectors obtained by CMOS-compatible wafer bonding

CERN Document Server

Bronuzzi, J.; Moll, M.; Sallese, J.M.

2016-01-01

In the framework of monolithic silicon radiation detectors, a fabrication process based on a recently developed silicon wafer bonding technique at low temperature was proposed. Ideally, this new process would enable direct bonding of a read-out electronic chip wafer on a highly resistive silicon substrate wafer, which is expected to present many advantages since it would combine high performance IC's with high sensitive ultra-low doped bulk silicon detectors. But electrical properties of the bonded interface are critical for this kind of application since the mobile charges generated by radiation inside the bonded bulk are expected to transit through the interface in order to be collected by the read-out electronics. In this work, we propose to explore and develop a model for the so-called Transient Current Technique (TCT) to identify the presence of deep traps at the bonded interface. For this purpose, we consider a simple PIN diode reversely biased where the ultra-low doped active region of interest is set ...

Integrating interface slicing into software engineering processes

Science.gov (United States)

Beck, Jon

1993-01-01

Interface slicing is a tool which was developed to facilitate software engineering. As previously presented, it was described in terms of its techniques and mechanisms. The integration of interface slicing into specific software engineering activities is considered by discussing a number of potential applications of interface slicing. The applications discussed specifically address the problems, issues, or concerns raised in a previous project. Because a complete interface slicer is still under development, these applications must be phrased in future tenses. Nonetheless, the interface slicing techniques which were presented can be implemented using current compiler and static analysis technology. Whether implemented as a standalone tool or as a module in an integrated development or reverse engineering environment, they require analysis no more complex than that required for current system development environments. By contrast, conventional slicing is a methodology which, while showing much promise and intuitive appeal, has yet to be fully implemented in a production language environment despite 12 years of development.

Unidirectional oxide hetero-interface thin-film diode

International Nuclear Information System (INIS)

Park, Youngmin; Lee, Eungkyu; Lee, Jinwon; Lim, Keon-Hee; Kim, Youn Sang

2015-01-01

The unidirectional thin-film diode based on oxide hetero-interface, which is well compatible with conventional thin-film fabrication process, is presented. With the metal anode/electron-transporting oxide (ETO)/electron-injecting oxide (EIO)/metal cathode structure, it exhibits that electrical currents ohmically flow at the ETO/EIO hetero-interfaces for only positive voltages showing current density (J)-rectifying ratio of ∼10 5 at 5 V. The electrical properties (ex, current levels, and working device yields) of the thin-film diode (TFD) are systematically controlled by changing oxide layer thickness. Moreover, we show that the oxide hetero-interface TFD clearly rectifies an AC input within frequency (f) range of 10 2  Hz < f < 10 6  Hz, providing a high feasibility for practical applications

Unidirectional oxide hetero-interface thin-film diode

Energy Technology Data Exchange (ETDEWEB)

Park, Youngmin; Lee, Eungkyu; Lee, Jinwon; Lim, Keon-Hee [Program in Nano Science and Technology, Graduate School of Convergence Science and Technology, Seoul National University, Seoul 151-742 (Korea, Republic of); Kim, Youn Sang, E-mail: younskim@snu.ac.kr [Program in Nano Science and Technology, Graduate School of Convergence Science and Technology, Seoul National University, Seoul 151-742 (Korea, Republic of); Advanced Institute of Convergence Technology, Gyeonggi-do 443-270 (Korea, Republic of)

2015-10-05

The unidirectional thin-film diode based on oxide hetero-interface, which is well compatible with conventional thin-film fabrication process, is presented. With the metal anode/electron-transporting oxide (ETO)/electron-injecting oxide (EIO)/metal cathode structure, it exhibits that electrical currents ohmically flow at the ETO/EIO hetero-interfaces for only positive voltages showing current density (J)-rectifying ratio of ∼10{sup 5} at 5 V. The electrical properties (ex, current levels, and working device yields) of the thin-film diode (TFD) are systematically controlled by changing oxide layer thickness. Moreover, we show that the oxide hetero-interface TFD clearly rectifies an AC input within frequency (f) range of 10{sup 2} Hz < f < 10{sup 6} Hz, providing a high feasibility for practical applications.

Brain-computer interfaces current trends and applications

CERN Document Server

Azar, Ahmad

2015-01-01

The success of a BCI system depends as much on the system itself as on the user’s ability to produce distinctive EEG activity. BCI systems can be divided into two groups according to the placement of the electrodes used to detect and measure neurons firing in the brain. These groups are: invasive systems, electrodes are inserted directly into the cortex are used for single cell or multi unit recording, and electrocorticography (EcoG), electrodes are placed on the surface of the cortex (or dura); noninvasive systems, they are placed on the scalp and use electroencephalography (EEG) or magnetoencephalography (MEG) to detect neuron activity. The book is basically divided into three parts. The first part of the book covers the basic concepts and overviews of Brain Computer Interface. The second part describes new theoretical developments of BCI systems. The third part covers views on real applications of BCI systems.

High temperature interface superconductivity

International Nuclear Information System (INIS)

Gozar, A.; Bozovic, I.

2016-01-01

Highlight: • This review article covers the topic of high temperature interface superconductivity. • New materials and techniques used for achieving interface superconductivity are discussed. • We emphasize the role played by the differences in structure and electronic properties at the interface with respect to the bulk of the constituents. - Abstract: High-T_c superconductivity at interfaces has a history of more than a couple of decades. In this review we focus our attention on copper-oxide based heterostructures and multi-layers. We first discuss the technique, atomic layer-by-layer molecular beam epitaxy (ALL-MBE) engineering, that enabled High-T_c Interface Superconductivity (HT-IS), and the challenges associated with the realization of high quality interfaces. Then we turn our attention to the experiments which shed light on the structure and properties of interfacial layers, allowing comparison to those of single-phase films and bulk crystals. Both ‘passive’ hetero-structures as well as surface-induced effects by external gating are discussed. We conclude by comparing HT-IS in cuprates and in other classes of materials, especially Fe-based superconductors, and by examining the grand challenges currently laying ahead for the field.

Induced- and alternating-current electro-osmotic control of the diffusion layer growth in a microchannel-membrane interface device

Science.gov (United States)

Park, Sinwook; Yossifon, Gilad

2014-11-01

The passage of an electric current through an ionic permselective medium under an applied electric field is characterized by the formation of ionic concentration gradients, which result in regions of depleted and enriched ionic concentration at opposite ends of the medium. Induced-current electro-osmosis (ICEO) and alternating-current-electro-osmosis (ACEO) are shown to control the growth of the diffusion layer (DL) which, in turn, controls the diffusion limited ion transport through the microchannel-membrane system. We fabricated and tested devices made of a Nafion membrane connecting two opposite PDMS microchannels. An interdigitated electrode array was embedded within the microchannel with various distances from the microchannel-membrane interface. The induced ICEO (floating electrodes) / ACEO (active electrodes) vortices formed at the electrode array stir the fluid and thereby suppress the growth of the DL. The intensity of the ACEO vortices is controlled by either varying the voltage amplitude or the frequency, each having its own unique effect. Enhancement of the limiting current by on-demand control of the diffusion length is of importance in on-chip electro-dialysis, desalination and preconcentration of analytes.

Ion-plated metal/ceramic interfaces

International Nuclear Information System (INIS)

Rigsbee, J.M.; Scott, P.A.; Knipe, R.K.; Ju, C.P.; Hock, V.F.

1986-01-01

Elemental Cu and Ti films have been deposited onto magnesia-alumina-silica ceramic substrates with a plasma-aided physical vapour deposition (ion-plating) process. Modifications in the structure and chemistry of the film, interface and substrate regions were investigated as a function of deposition process parameters (eg applied bias, voltage and current). The strength of the Cu/ceramic interface was found to be strongly influenced by both applied substrate bias voltage and substrate roughness. Films deposited with an applied substrate bias showed increasing adhesive strength with increasing bias. Microchemical analysis indicated that this enhanced adhesion is directly correlated with the development of a chemically graded interface region. The adhesive strength of the ion plated Cu films was also found to be improved with increasing substrate smoothness. The behaviour of Ti was found to be quite different from that of Cu. Ti generally has superior adhesion. This adhesion decreased for films deposited with a high bias voltage/current. From interfacial TEM it is shown that this is due to the formation of a compound at the Ti/ceramic interface. The thickness of this compound is important in adhesion. (UK)

Surface and interface sciences of Li-ion batteries. -Research progress in electrode-electrolyte interface-

Science.gov (United States)

Minato, Taketoshi; Abe, Takeshi

2017-12-01

The application potential of Li-ion batteries is growing as demand increases in different fields at various stages in energy systems, in addition to their conventional role as power sources for portable devices. In particular, applications in electric vehicles and renewable energy storage are increasing for Li-ion batteries. For these applications, improvements in battery performance are necessary. The Li-ion battery produces and stores electric power from the electrochemical redox reactions between the electrode materials. The interface between the electrodes and electrolyte strongly affects the battery performance because the charge transfer causing the electrode redox reaction begins at this interface. Understanding of the surface structure, electronic structure, and chemical reactions at the electrode-electrolyte interface is necessary to improve battery performance. However, the interface is located between the electrode and electrolyte materials, hindering the experimental analysis of the interface; thus, the physical properties and chemical processes have remained poorly understood until recently. Investigations of the physical properties and chemical processes at the interface have been performed using advanced surface science techniques. In this review, current knowledge and future research prospects regarding the electrode-electrolyte interface are described for the further development of Li-ion batteries.

Scattering theory of ballistic-electron-emission microscopy at nonepitaxial interfaces

International Nuclear Information System (INIS)

Smith, D. L.; Kozhevnikov, M.; Lee, E. Y.; Narayanamurti, V.

2000-01-01

We present an interface scattering model to describe ballistic-electron-emission microscopy (BEEM) at nonepitaxial metal/semiconductor interfaces. The model starts with a Hamiltonian consisting of the sum of two terms: one term, H 0 , describes an ideal interface for which the interface parallel component of wave vector is a good quantum number, and the second term, δH, describes interfacial scattering centers. The eigenstates of H 0 consist of an incident and a reflected part in the metal and a transmitted part in the semiconductor. The three components of each eigenstate have the same interface parallel wave vector. Because tunneling preferentially weights forward-directed states, the interface parallel component of wave vector is small for the H 0 eigenstates that are initially populated with high probability in BEEM. δH scatters electrons between the eigenstates of H 0 . The scattering conserves energy, but not the interface parallel wave vector. In the final state of the scattering process, states with a large interface parallel wave vector can be occupied with reasonable probability. If scattering is weak, so that the parallel wave vector is nearly conserved, the calculated collector current into conduction-band valleys with zero parallel wave vector at the minimum, such as the Γ valley for GaAs(100), is much larger than the calculated collector current into conduction-band valleys with a large parallel wave vector at the minimum, such as the L valleys for GaAs(100). However, if scattering is strong, the injected electron flux distribution is redistributed and valleys with zero interface transverse wave vector at their energy minimum are not preferentially weighted. Instead, the weighting varies as the density of final states for the scattering process so that, for example, the calculated L-channel collector current is much larger than the calculated Γ-channel collector current for GaAs(100). Interfacial scattering reduces the overall magnitude of the

User Interface Cultures of Mobile Knowledge Workers

Directory of Open Access Journals (Sweden)

Petri Mannonen

2008-10-01

Full Text Available Information and communication tools (ICTs have become a major influencer of how modern work is carried out. Methods of user-centered design do not however take into account the full complexity of technology and the user interface context the users live in. User interface culture analysis aims providing to designers new ways and strategies to better take into account the current user interface environment when designing new products. This paper describes the reasons behind user interface culture analysis and shows examples of its usage when studying mobile and distributed knowledge workers.

Silicon/HfO2 interface: Effects of proton irradiation

International Nuclear Information System (INIS)

Maurya, Savita; Radhakrishna, M.

2015-01-01

Substrate oxide interfaces are of paramount importance in deciding the quality of the semiconductor devices. In this work we have studied how 200 keV proton irradiation affects the interface of a 13 nm thick, atomic layer deposited hafnium dioxide on silicon substrate. Pre- and post-irradiation electrical measurements are used to quantify the effect of proton irradiation for varying electrode geometries. Proton irradiation introduces positive charge in the oxide and at the interface of Si/HfO 2 interface. The gate current is not very much affected under positive injection since the induced positive charge is compensated by the injected electrons. Current voltage characteristics under negative bias get affected by the proton irradiation

Interface-Enhanced Spin-Orbit Torques and Current-Induced Magnetization Switching of Pd /Co /AlOx Layers

Science.gov (United States)

Ghosh, Abhijit; Garello, Kevin; Avci, Can Onur; Gabureac, Mihai; Gambardella, Pietro

2017-01-01

Magnetic heterostructures that combine large spin-orbit torque efficiency, perpendicular magnetic anisotropy, and low resistivity are key to developing electrically controlled memory and logic devices. Here, we report on vector measurements of the current-induced spin-orbit torques and magnetization switching in perpendicularly magnetized Pd /Co /AlOx layers as a function of Pd thickness. We find sizable dampinglike (DL) and fieldlike (FL) torques, on the order of 1 mT per 107 A /cm2 , which have different thicknesses and magnetization angle dependencies. The analysis of the DL torque efficiency per unit current density and the electric field using drift-diffusion theory leads to an effective spin Hall angle and spin-diffusion length of Pd larger than 0.03 and 7 nm, respectively. The FL spin-orbit torque includes a significant interface contribution, is larger than estimated using drift-diffusion parameters, and, furthermore, is strongly enhanced upon rotation of the magnetization from the out-of-plane to the in-plane direction. Finally, taking advantage of the large spin-orbit torques in this system, we demonstrate bipolar magnetization switching of Pd /Co /AlOx layers with a similar current density to that used for Pt /Co layers with a comparable perpendicular magnetic anisotropy.

Effects of a highly Si-doped GaN current spreading layer at the n+-GaN/multi-quantum-well interface on InGaN/GaN blue-light-emitting diodes

International Nuclear Information System (INIS)

Kim, C. S.; Cho, H. K.; Choi, R. J.; Hahn, Y. B.; Lee, H. J.; Hong, C. H.

2004-01-01

Highly Si-doped GaN thin current spreading layer (CSL) with various carrier concentrations were inserted before the n + -GaN/multi-quantum-well (MQW) interface controlled by the growth rate and the modulated Si-doping in InGaN/GaN blue light-emitting diodes (LEDs), and their effects were investigated by using capacitance-voltage (C-V), current-voltage (I-V), and output power measurements. The LEDs with a highly Si-doped CSL show enhanced I-V characteristics and increased output power with increasing carrier concentration up to some critical point in the CSL. This means that proper high Si-doping in some limited area before the interface may enhance the device performance through the current spreading effect.

Current Control and Performance Evaluation of Converter Interfaced Distribution Resources in Grid Connected Mode

Directory of Open Access Journals (Sweden)

SINGH Alka

2012-10-01

Full Text Available Use of distributed resources is growing in developing countries like India and in developed nations too. The increased acceptance of suchresources is mainly due to their modularity, increased reliability, good power quality and environment friendly operation. These are currently being interfaced to the existing systems using voltage source inverters (VSC’s. The control of such distributed resources is significantly different than the conventional power systems mainly because the VSC’s have no inertia unlike the synchronous generators.This paper deals with the Matlab modeling and design of control aspects of one such distributed source feeding a common load. A grid connected supply is also available. The control algorithm is developed for real and reactive power sharing of the load between thedistributed source and the grid. The developed control scheme is tested for linear (R-L load as well as nonlinear loads. With suitable modifications, the control algorithm can be extended for several distributed resources connected in parallel.

Interactive displays natural human-interface technologies

CERN Document Server

Bhowmik, Achintya K

2014-01-01

One of the first books to provide an in-depth discussion of the technologies, applications and trends in the rapidly emerging field of interactive displays (touch, gesture & voice) The book will cover the technologies, applications and trends in the field of interactive displays, namely interfaces based on touch, gesture and voice and those using a combination of these technologies. The book will be split into 4 main parts with each being dedicated to a specific user interface. Part 1 ''Touch Interfaces'' will provide a review of the currently deployed touch-screen technologies and applications. It will also cover the recent developments towards achieving thinner, lightweight and cost-reduced touch screen panels in the future via integration of touch functionalities. Part 2 ''Gesture Interfaces'' will examine techniques and applications in stereoscopic 3D computer vision, structured-light 3D computer vision and time-of-flight 3D computer vision in gesture interfaces. Part 3 ''Voice Interfaces'' will revie...

Electronic structure of semiconductor interfaces

Energy Technology Data Exchange (ETDEWEB)

Herman, F

1983-02-01

The study of semiconductor interfaces is one of the most active and exciting areas of current semiconductor research. Because interfaces play a vital role in modern semiconductor technology (integrated circuits, heterojunction lasers, solar cells, infrared detectors, etc.), there is a strong incentive to understand interface properties at a fundamental level and advance existing technology thereby. At the same time, technological advances such as molecular beam epitaxy have paved the way for the fabrication of semiconductor heterojunctions and superlattices of novel design which exhibit unusual electronic, optical, and magnetic properties and offer unique opportunities for fundamental scientific research. A general perspective on this subject is offered treating such topics as the atomic and electronic structure of semiconductor surfaces and interfaces; oxidation and oxide layers; semiconductor heterojunctions and superlattices; rectifying metal-semiconductor contacts; and interface reactions. Recent progress is emphasized and some future directions are indicated. In addition, the role that large-scale scientific computation has played in furthering our theoretical understanding of semiconductor surfaces and interfaces is discussed. Finally, the nature of theoretical models, and the role they play in describing the physical world is considered.

Electronic structure of semiconductor interfaces

International Nuclear Information System (INIS)

Herman, F.

1983-01-01

The study of semiconductor interfaces is one of the most active and exciting areas of current semiconductor research. Because interfaces play a vital role in modern semiconductor technology (integrated circuits, heterojunction lasers, solar cells, infrared detectors, etc.), there is a strong incentive to understand interface properties at a fundamental level and advance existing technology thereby. At the same time, technological advances such as molecular beam epitaxy have paved the way for the fabrication of semiconductor heterojunctions and superlattices of novel design which exhibit unusual electronic, optical, and magnetic properties and offer unique opportunities for fundamental scientific research. A general perspective on this subject is offered treating such topics as the atomic and electronic structure of semiconductor surfaces and interfaces; oxidation and oxide layers; semiconductor heterojunctions and superlattices; rectifying metal-semiconductor contacts; and interface reactions. Recent progress is emphasized and some future directions are indicated. In addition, the role that large-scale scientific computation has played in furthering our theoretical understanding of semiconductor surfaces and interfaces is discussed. Finally, the nature of theoretical models, and the role they play in describing the physical world is considered. (Author) [pt

Review of results from SKB R and D on grouting technology for sealing the rock, years 1996-2000

International Nuclear Information System (INIS)

Boden, A.; Eklund, D.; Eriksson, Magnus; Lagerblad, B.; Lindblom, U.

2001-05-01

In order identify the current state of the art and developments needs, SKB assembled a group of experts from universities and other research organisations. Internal plans were written for the subprojects 'Characterisation of rock for grouting purposes', 'Mechanisms that control the spreading of grout in jointed rock' and 'Cement based grouting material'. Later internal plans for the subprojects 'Demands on grouting' and 'Stabilising and sealing effect of pre-grouting' were written. The aims, which were set for the different subprojects, were in short, to summarise the technological advances, establish a method for rock characterisation from a grouting point of view, develop conceptual and numerical models for simulation of the grouting course, characterise grout in a relevant way, develop understanding and theoretical know-how of durability and chemical influence, identify and develop a number of grouting materials for different situations, develop a specification of requirements for grouting and to verify the theories in laboratory. In the subproject 'Demands on grouting' a literature review was carried out. One important conclusion from the study is that the concept is not very well dealt with in the literature. SKB are currently investigating the prerequisites for the construction of the deep repository. One part of that work is to further specify demands on maximum allowed volume of leakage water for the repository as a whole and also for each part of the deep repository. In the subproject 'Characterisation of rock for grouting purposes', the possibilities of using hydraulic tests for predictions and design have been studied. The idea of this study was to investigate correspondences and deviations to increase the understanding of what is measured in a water-loss measurement. One can draw the conclusion that hydraulic tests are useful when describing the fracture geometry. Numerical modelling and experiments indicate that the specific capacity, Q/Δh, (flow

Influence of interface roughness in quantum cascade lasers

International Nuclear Information System (INIS)

Krivas, K. A.; Winge, D. O.; Franckié, M.; Wacker, A.

2015-01-01

We use a numerical model based on non-equilibrium Green's functions to investigate the influence of interface roughness (IFR) scattering in terahertz quantum cascade lasers. We confirm that IFR is an important phenomenon that affects both current and gain. The simulations indicate that IFR causes a leakage current that transfers electrons from the upper to the lower laser state. In certain cases, this current can greatly reduce gain. In addition, individual interfaces and their impact on the renormalized single particle energies are studied and shown to give both blue- and red-shifts of the gain spectrum

XML Translator for Interface Descriptions

Science.gov (United States)

Boroson, Elizabeth R.

2009-01-01

A computer program defines an XML schema for specifying the interface to a generic FPGA from the perspective of software that will interact with the device. This XML interface description is then translated into header files for C, Verilog, and VHDL. User interface definition input is checked via both the provided XML schema and the translator module to ensure consistency and accuracy. Currently, programming used on both sides of an interface is inconsistent. This makes it hard to find and fix errors. By using a common schema, both sides are forced to use the same structure by using the same framework and toolset. This makes for easy identification of problems, which leads to the ability to formulate a solution. The toolset contains constants that allow a programmer to use each register, and to access each field in the register. Once programming is complete, the translator is run as part of the make process, which ensures that whenever an interface is changed, all of the code that uses the header files describing it is recompiled.

Photovoltaic array: Power conditioner interface characteristics

Science.gov (United States)

Gonzalez, C. C.; Hill, G. M.; Ross, R. G., Jr.

1982-01-01

The electrical output (power, current, and voltage) of flat plate solar arrays changes constantly, due primarily to changes in cell temperature and irradiance level. As a result, array loads such as dc-to-ac power conditioners must be capable of accommodating widely varying input levels while maintaining operation at or near the maximum power point of the array. The array operating characteristics and extreme output limits necessary for the systematic design of array load interfaces under a wide variety of climatic conditions are studied. A number of interface parameters are examined, including optimum operating voltage, voltage energy, maximum power and current limits, and maximum open circuit voltage. The effect of array degradation and I-V curve fill factor or the array power conditioner interface is also discussed. Results are presented as normalized ratios of power conditioner parameters to array parameters, making the results universally applicable to a wide variety of system sizes, sites, and operating modes.

What are the current solutions for interfacing supercritical fluid chromatography and mass spectrometry?

Science.gov (United States)

Guillarme, Davy; Desfontaine, Vincent; Heinisch, Sabine; Veuthey, Jean-Luc

2018-04-15

Mass spectrometry (MS) is considered today as one of the most popular detection methods, due to its high selectivity and sensitivity. In particular, this detector has become the gold standard for the analysis of complex mixtures such as biological samples. The first successful SFC-MS hyphenation was reported in the 80's, and since then, several ionization sources, mass analyzers and interfacing technologies have been combined. Due to the specific physicochemical properties and compressibility of the SFC mobile phase, directing the column effluent into the ionization source is more challenging than in LC. Therefore, some specific interfaces have to be employed in SFC-MS, to i) avoid (or at least limit) analytes precipitation due to CO 2 decompression, when the SFC mobile phase is not anymore under backpressure control, ii) achieve adequate ionization yield, even with a low proportion of MeOH in the mobile phase and iii) preserve the chromatographic integrity (i.e. maintaining retention, selectivity, and efficiency). The goal of this review is to describe the various SFC-MS interfaces and highlight the most favorable ones in terms of reliability, flexibility, sensitivity and user-friendliness. Copyright © 2018 Elsevier B.V. All rights reserved.

DTK C/Fortran Interface Development for NEAMS FSI Simulations

Energy Technology Data Exchange (ETDEWEB)

Slattery, Stuart R. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Lebrun-Grandie, Damien T. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

2016-09-19

This report documents the development of DataTransferKit (DTK) C and Fortran interfaces for fluid-structure-interaction (FSI) simulations in NEAMS. In these simulations, the codes Nek5000 and Diablo are being coupled within the SHARP framework to study flow-induced vibration (FIV) in reactor steam generators. We will review the current Nek5000/Diablo coupling algorithm in SHARP and the current state of the solution transfer scheme used in this implementation. We will then present existing DTK algorithms which may be used instead to provide an improvement in both flexibility and scalability of the current SHARP implementation. We will show how these can be used within the current FSI scheme using a new set of interfaces to the algorithms developed by this work. These new interfaces currently expose the mesh-free solution transfer algorithms in DTK, a C++ library, and are written in C and Fortran to enable coupling of both Nek5000 and Diablo in their native Fortran language. They have been compiled and tested on Cooley, the test-bed machine for Mira at ALCF.

Robust Brain-Computer Interfaces

NARCIS (Netherlands)

Reuderink, B.

2011-01-01

A brain-computer interface (BCI) enables direct communication from the brain to devices, bypassing the traditional pathway of peripheral nerves and muscles. Current BCIs aimed at patients require that the user invests weeks, or even months, to learn the skill to intentionally modify their brain

Corrosion at the head-neck interface of current designs of modular femoral components: essential questions and answers relating to corrosion in modular head-neck junctions.

Science.gov (United States)

Osman, K; Panagiotidou, A P; Khan, M; Blunn, G; Haddad, F S

2016-05-01

There is increasing global awareness of adverse reactions to metal debris and elevated serum metal ion concentrations following the use of second generation metal-on-metal total hip arthroplasties. The high incidence of these complications can be largely attributed to corrosion at the head-neck interface. Severe corrosion of the taper is identified most commonly in association with larger diameter femoral heads. However, there is emerging evidence of varying levels of corrosion observed in retrieved components with smaller diameter femoral heads. This same mechanism of galvanic and mechanically-assisted crevice corrosion has been observed in metal-on-polyethylene and ceramic components, suggesting an inherent biomechanical problem with current designs of the head-neck interface. We provide a review of the fundamental questions and answers clinicians and researchers must understand regarding corrosion of the taper, and its relevance to current orthopaedic practice. Cite this article: Bone Joint J 2016;98-B:579-84. ©2016 The British Editorial Society of Bone & Joint Surgery.

Integrated computer network high-speed parallel interface

International Nuclear Information System (INIS)

Frank, R.B.

1979-03-01

As the number and variety of computers within Los Alamos Scientific Laboratory's Central Computer Facility grows, the need for a standard, high-speed intercomputer interface has become more apparent. This report details the development of a High-Speed Parallel Interface from conceptual through implementation stages to meet current and future needs for large-scle network computing within the Integrated Computer Network. 4 figures

Human Reliability and the Current Dilemma in Human-Machine Interface Design Strategies

International Nuclear Information System (INIS)

Passalacqua, Roberto; Yamada, Fumiaki

2002-01-01

Since human error dominates the probability of failures of still-existing human-requiring systems (as the Monju reactor), the human-machine interface needs to be improved. Several rationales may lead to the conclusion that 'humans' should limit themselves to monitor the 'machine'. For example, this is the trend in the aviation industry: newest aircrafts are designed to be able to return to a safe state by the use of control systems, which do not need human intervention. Thus, the dilemma whether we really need operators (for example in the nuclear industry) might arise. However, social-technical approaches in recent human error analyses are pointing out the so-called 'organizational errors' and the importance of a human-machine interface harmonization. Typically plant's operators are a 'redundant' safety system with a much lower reliability (than the machine): organizational factors and harmonization requirements suggest designing the human-machine interface in a way that allows improvement of operator's reliability. In addition, taxonomy studies of accident databases have also proved that operators' training should promote processes of decision-making. This is accomplished in the latest trends of PSA technology by introducing the concept of a 'Safety Monitor' that is a computer-based tool that uses a level 1 PSA model of the plant. Operators and maintenance schedulers of the Monju FBR will be able to perform real-time estimations of the plant risk level. The main benefits are risk awareness and improvements in decision-making by operators. Also scheduled maintenance can be approached in a more rational (safe and economic) way. (authors)

Electrode-electrolyte interface model of tripolar concentric ring electrode and electrode paste.

Science.gov (United States)

Nasrollaholhosseini, Seyed Hadi; Steele, Preston; Besio, Walter G

2016-08-01

Electrodes are used to transform ionic currents to electrical currents in biological systems. Modeling the electrode-electrolyte interface could help to optimize the performance of the electrode interface to achieve higher signal to noise ratios. There are previous reports of accurate models for single-element biomedical electrodes. In this paper we develop a model for the electrode-electrolyte interface for tripolar concentric ring electrodes (TCRE) that are used to record brain signals.

Joint ANDRA/Nirex/SKB zone of excavation disturbance experiment (ZEDEX) at the Aspo hard rock laboratory

International Nuclear Information System (INIS)

Hooper, A.J.; Olsson, O.

1995-01-01

The excavation of access shafts and tunnels and of the disposal areas of a waste repository will cause a disturbance in the surrounding rock mass with possible alterations to rock mass stability and hydraulic properties. For a number of disposal concepts this disturbance may be important for the operational and/or post-closure safety of the repository. Furthermore the disturbance may extend over time as a consequence of processes such as stress relaxation. The sponsors of ZEDEX, namely ANDRA, Nirex and SKB, are interested in developing the ability to produce reliable models of the disturbed zone that will develop around large cross-section excavations in fractured hard rock masses that are initially water saturated. Various models have been developed to calculate the important characteristics of the disturbed zone in such rock masses as a function of parameters related to the rock mass quality and the geometric description of the excavation. ZEDEX was initiated in the Aspo Hard Rock Laboratory in April 1994 with drilling and instrumentation of boreholes running alongside the planned extension of the spiral access ramp and a planned parallel experimental tunnel. ZEDEX has been designed to generate information for alternative methods of excavation. The extension to the spiral ramp is to be made by tunnel boring whereas the parallel experimental tunnel will be excavated in part by ''normal'' basting and in part by smooth blasting. The objective is to build confidence in the modelling of the disturbed zone to support the selection of excavation methods for repository construction. (authors). 3 figs

Connections that Count: Brain-Computer Interface Enables the Profoundly Paralyzed to Communicate

Science.gov (United States)

... Home Current Issue Past Issues Connections that Count: Brain-Computer Interface Enables the Profoundly Paralyzed to Communicate Past Issues / ... of this page please turn Javascript on. A brain-computer interface (BCI) system This brain-computer interface (BCI) system ...

Non-linear response of electrode-electrolyte interface at high current density

International Nuclear Information System (INIS)

Ruiz, G.A.; Felice, C.J.; Valentinuzzi, M.E.

2005-01-01

A distributed parameter non-linear circuit is presented as fractal model of an electrode-electrolyte interface. It includes the charge transfer resistance and the double layer capacitance at each fractal level. The circuit explains the linear behavior of its series equivalent resistance R eq with signals of amplitudes eq Fourier spectrum. As a consequence, both the equivalent resistance and reactance drop with voltage, facts reported experimentally by other authors

Concept of software interface for BCI systems

Science.gov (United States)

Svejda, Jaromir; Zak, Roman; Jasek, Roman

2016-06-01

Brain Computer Interface (BCI) technology is intended to control external system by brain activity. One of main part of such system is software interface, which carries about clear communication between brain and either computer or additional devices connected to computer. This paper is organized as follows. Firstly, current knowledge about human brain is briefly summarized to points out its complexity. Secondly, there is described a concept of BCI system, which is then used to build an architecture of proposed software interface. Finally, there are mentioned disadvantages of sensing technology discovered during sensing part of our research.

Interface matrix method in AFEN framework

Energy Technology Data Exchange (ETDEWEB)

Pogosbekyan, Leonid; Cho, Jin Young; Kim, Young Jin [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

1998-12-31

In this study, we extend the application of the interface-matrix(IM) method for reflector modeling to Analytic Flux Expansion Nodal (AFEN) method. This include the modifications of the surface-averaged net current continuity and the net leakage balance conditions for IM method in accordance with AFEN formula. AFEN-interface matrix (AFEN-IM) method has been tested against ZION-1 benchmark problem. The numerical result of AFEN-IM method shows 1.24% of maximum error and 0.42% of root-mean square error in assembly power distribution, and 0.006% {Delta} k of neutron multiplication factor. This result proves that the interface-matrix method for reflector modeling can be useful in AFEN method. 3 refs., 4 figs. (Author)

Interface matrix method in AFEN framework

Energy Technology Data Exchange (ETDEWEB)

Pogosbekyan, Leonid; Cho, Jin Young; Kim, Young Jin [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

1997-12-31

In this study, we extend the application of the interface-matrix(IM) method for reflector modeling to Analytic Flux Expansion Nodal (AFEN) method. This include the modifications of the surface-averaged net current continuity and the net leakage balance conditions for IM method in accordance with AFEN formula. AFEN-interface matrix (AFEN-IM) method has been tested against ZION-1 benchmark problem. The numerical result of AFEN-IM method shows 1.24% of maximum error and 0.42% of root-mean square error in assembly power distribution, and 0.006% {Delta} k of neutron multiplication factor. This result proves that the interface-matrix method for reflector modeling can be useful in AFEN method. 3 refs., 4 figs. (Author)

Current trends in hardware and software for brain-computer interfaces (BCIs).

Science.gov (United States)

Brunner, P; Bianchi, L; Guger, C; Cincotti, F; Schalk, G

2011-04-01

A brain-computer interface (BCI) provides a non-muscular communication channel to people with and without disabilities. BCI devices consist of hardware and software. BCI hardware records signals from the brain, either invasively or non-invasively, using a series of device components. BCI software then translates these signals into device output commands and provides feedback. One may categorize different types of BCI applications into the following four categories: basic research, clinical/translational research, consumer products, and emerging applications. These four categories use BCI hardware and software, but have different sets of requirements. For example, while basic research needs to explore a wide range of system configurations, and thus requires a wide range of hardware and software capabilities, applications in the other three categories may be designed for relatively narrow purposes and thus may only need a very limited subset of capabilities. This paper summarizes technical aspects for each of these four categories of BCI applications. The results indicate that BCI technology is in transition from isolated demonstrations to systematic research and commercial development. This process requires several multidisciplinary efforts, including the development of better integrated and more robust BCI hardware and software, the definition of standardized interfaces, and the development of certification, dissemination and reimbursement procedures.

Current trends in hardware and software for brain-computer interfaces (BCIs)

Science.gov (United States)

Brunner, P.; Bianchi, L.; Guger, C.; Cincotti, F.; Schalk, G.

2011-04-01

A brain-computer interface (BCI) provides a non-muscular communication channel to people with and without disabilities. BCI devices consist of hardware and software. BCI hardware records signals from the brain, either invasively or non-invasively, using a series of device components. BCI software then translates these signals into device output commands and provides feedback. One may categorize different types of BCI applications into the following four categories: basic research, clinical/translational research, consumer products, and emerging applications. These four categories use BCI hardware and software, but have different sets of requirements. For example, while basic research needs to explore a wide range of system configurations, and thus requires a wide range of hardware and software capabilities, applications in the other three categories may be designed for relatively narrow purposes and thus may only need a very limited subset of capabilities. This paper summarizes technical aspects for each of these four categories of BCI applications. The results indicate that BCI technology is in transition from isolated demonstrations to systematic research and commercial development. This process requires several multidisciplinary efforts, including the development of better integrated and more robust BCI hardware and software, the definition of standardized interfaces, and the development of certification, dissemination and reimbursement procedures.

International Peer Review of Swedish Nuclear Fuel and Waste Management Company's SR-Can interim report

International Nuclear Information System (INIS)

Sagar, Budhi; Bailey, Lucy; Bennett, David G.; Egan, Mike; Roehlig, Klaus

2004-12-01

demonstration (e.g. allocation of safety to different barrier functions and the role of dilution); Basis and methods for scenario selection and evaluation; Assessment of model framework for consequence analysis and compliance evaluation (e.g. justification of models, and parameters); Methods for biosphere modelling including the transition zone from basement rock to quaternary deposits and ecosystems; Methods for risk analysis, including the use of probabilistic methods, uncertainty and sensitivity analysis, estimation of probabilities, averaging of risk; and Quality assurance measures including handling of expert judgments. Among its conclusions, the IRT considers that the SR-Can Interim Report describes a logical methodology for undertaking a safety assessment that could be used as a component of a safety case to support a licence application. SKB's assessment methodology also includes some innovative and positive components, such as the use of safety function indicators and analytical models. From the IRT's perspective, the main deficiencies in SKB's programme and approach relate less to the methodology and more to the rigour with which safety assessment needs to be conducted to support a formal licence application. There are a number of areas, for example in the development of scenarios and in the management and treatment of uncertainty, where current evidence suggests a need for greater clarity and traceability. More generally, it is recommended that SKB should ensure that all aspects of the safety assessment are conducted in accordance with auditable project-specific guidance and QA procedures. In view of the above, and the fact that SKB has acknowledged that some further development work remains to be done, the IRT believes that it could be a challenge for SKB to conduct and present a safety assessment of suitable quality within the currently proposed timescale for delivery of the SR-Can assessment and the 2006 licence application

Historical Overview, Current Status, and Future Trends in Human-Computer Interfaces for Process Control

International Nuclear Information System (INIS)

Owre, Fridtjov

2003-01-01

Approximately 25 yr ago, the first computer-based process control systems, including computer-generated displays, appeared. It is remarkable how slowly the human-computer interfaces (HCI's) of such systems have developed over the years. The display design approach in those early days had its roots in the topology of the process. Usually, the information came from the piping and instrumentation diagrams. Later, some important additional functions were added to the basic system, such as alarm and trend displays. Today, these functions are still the basic ones, and the end-user displays have not changed much except for improved display quality in terms of colors, font types and sizes, resolution, and object shapes, resulting from improved display hardware.Today, there are two schools of display design competing for supremacy in the process control segment of the HCI community. One can be characterized by extension and integration of current practice, while the other is more revolutionary.The extension of the current practice approach can be described in terms of added system functionality and integration. This means that important functions for the plant operator - such as signal validation, plant overview information, safety parameter displays, procedures, prediction of future states, and plant performance optimization - are added to the basic functions and integrated in a total unified HCI for the plant operator.The revolutionary approach, however, takes as its starting point the design process itself. The functioning of the plant is described in terms of the plant goals and subgoals, as well as the means available to reach these goals. Then, displays are designed representing this functional structure - in clear contrast to the earlier plant topology representation. Depending on the design approach used, the corresponding displays have various designations, e.g., function-oriented, task-oriented, or ecological displays.This paper gives a historical overview of past

Spin Current Noise of the Spin Seebeck Effect and Spin Pumping

Science.gov (United States)

Matsuo, M.; Ohnuma, Y.; Kato, T.; Maekawa, S.

2018-01-01

We theoretically investigate the fluctuation of a pure spin current induced by the spin Seebeck effect and spin pumping in a normal-metal-(NM-)ferromagnet(FM) bilayer system. Starting with a simple ferromagnet-insulator-(FI-)NM interface model with both spin-conserving and non-spin-conserving processes, we derive general expressions of the spin current and the spin-current noise at the interface within second-order perturbation of the FI-NM coupling strength, and estimate them for a yttrium-iron-garnet-platinum interface. We show that the spin-current noise can be used to determine the effective spin carried by a magnon modified by the non-spin-conserving process at the interface. In addition, we show that it provides information on the effective spin of a magnon, heating at the interface under spin pumping, and spin Hall angle of the NM.

Atomistic calculations of interface elastic properties in noncoherent metallic bilayers

International Nuclear Information System (INIS)

Mi Changwen; Jun, Sukky; Kouris, Demitris A.; Kim, Sung Youb

2008-01-01

The paper describes theoretical and computational studies associated with the interface elastic properties of noncoherent metallic bicrystals. Analytical forms of interface energy, interface stresses, and interface elastic constants are derived in terms of interatomic potential functions. Embedded-atom method potentials are then incorporated into the model to compute these excess thermodynamics variables, using energy minimization in a parallel computing environment. The proposed model is validated by calculating surface thermodynamic variables and comparing them with preexisting data. Next, the interface elastic properties of several fcc-fcc bicrystals are computed. The excess energies and stresses of interfaces are smaller than those on free surfaces of the same crystal orientations. In addition, no negative values of interface stresses are observed. Current results can be applied to various heterogeneous materials where interfaces assume a prominent role in the systems' mechanical behavior

Hydrochemical investigations in crystalline bedrock in relation to existing hydraulic conditions: experiences from the SKB test-sites in Sweden

International Nuclear Information System (INIS)

Smellie, J.; Larsson, N.Aa.; Wikberg, P.; Carlsson, L.

1985-11-01

This report represents the compilation, discussion and interpretation of hydrochemical and hydraulic data resulting from the SKB test-site investigations carried out over a period of three years (1982-84). By systematically applying hydrological and geological considerations to each sampled horizon, it has been possible to differentiate between those groundwaters which are reasonably representative for the depth sampled, from those which have been subject to contamination from different sources. Groundwaters which are here considered representative are defined as those which show no evidence of mixing with other water sources, whether from drilling water, younger, near-surface water, or other deeper groundwaters. As a consequence, only a few sampled horizons can be considered with serious hydrochemical attention. The lack of representative groundwater samples, whilst often due to technical problems or sampling from non-conductive sections of the boreholes, also illustrate the extremely complex geometry of the premeable fracture systems in crystalline bedrock, and thus the difficulty of establishing the nature and depth relation of the groundwater tapped. Although the main findings of this study have revealed gross inadequacies in the hydrochemical programme, valuable experience has nevertheless been gained. Consequently, some of the improvements recommended in Section 7 of this report have been already implemented resulting in higher sampling standards and thus water samples which are much more representative for the hydrogeological environment under investigation. (author)

Fluid mechanics of environmental interfaces

CERN Document Server

Gualtieri, Carlo

2012-01-01

Preface Preface of the first editionBiographies of the authors Part one - Preliminaries1. Environmental fluid mechanics: Current issues and future outlook B. Cushman-Roisin, C. Gualtieri & D.T. MihailovicPart two - Processes at atmospheric interfaces2. Point source atmospheric diffusionB. Rajkovic, I. Arsenic & Z. Grsic3. Air-sea interaction V. Djurdjevic & B. Rajkovic4. Modelling of flux exchanges between heterogeneous surfaces and atmosphere D.T. Mihailovic & D. Kapor5. Desert dust uptake-transport and deposition mechanisms - impacts of dust on radiation, clouds and precipitation G. Kallos, P. Katsafados & C. SpyrouPart three - Processes at water interfaces6. Gas-transfer at unsheared free-surfaces C. Gualtieri & G. Pulci Doria7. Advective diffusion of air bubbles in turbulent water flows H. Chanson8. Exchanges at the bed sediments-water column interface F.A. Bombardelli & P.A. Moreno9. Surface water and streambed sediment interaction: The hyporheic exchange D. Tonina10. Environm...

The Effects of High Salinity Groundwater on the Performance of Clay Barriers

International Nuclear Information System (INIS)

Savage, David

2005-08-01

Potential changes in groundwater chemistry during the operational or post-closure periods of the Swedish repository for spent fuel could affect the performance of both the bentonite buffer and repository backfill. For example, the up-coning of saline groundwater could lead to decreased swelling pressures in both the bentonite buffer and tunnel backfills, and could also induce 'piping'. SKB is considering these issues as part of its 'SR-Can' safety assessment. This report reviews evidence for the behaviour of swelling clays in groundwaters of varying salinity with special relevance to the SKB programme. Smectite clays can absorb water into clay inter-layers with the most important parameters being: the surface density of charge of the clay; the charge and solvation behaviour of the inter-layer ions; and the electrolyte concentration or activity of water. Two categories of swelling are generally observed: innercrystalline swelling caused by the hydration of the exchangeable cations in the dry clay; and osmotic swelling, resulting from concentration gradients in ion concentrations between clay surfaces and pore water. Several models exist to interpret and predict the swelling behaviour of clays. SKB currently prefer an interpretation of clay swelling pressure where clay particles are viewed as 'macro-ions' and the entire clay-water system can be considered as a 'polyelectrolyte'. SKB use the term 'Donnan exclusion' to estimate the amount of introduced ions into the clay and hence the amount of reduced swelling pressure due to contact with a saline solution. Donnan exclusion is the process whereby the migration of anions through the narrow aqueous film surrounding clay platelets is restricted due to the repulsion by the negative charge of the clay platelets. SKB's experimental work shows that: There is an exponential relation between swelling pressure and mean basal interlamellar spacing of the clay. Ions from the external electrolyte solution enter the clay volume

The Effects of High Salinity Groundwater on the Performance of Clay Barriers

Energy Technology Data Exchange (ETDEWEB)

Savage, David [Quintessa Ltd., Nottingham (United Kingdom)

2005-07-01

Potential changes in groundwater chemistry during the operational or post-closure periods of the Swedish repository for spent fuel could affect the performance of both the bentonite buffer and repository backfill. For example, the up-coning of saline groundwater could lead to decreased swelling pressures in both the bentonite buffer and tunnel backfills, and could also induce 'piping'. SKB is considering these issues as part of its 'SR-Can' safety assessment. This report reviews evidence for the behaviour of swelling clays in groundwaters of varying salinity with special relevance to the SKB programme. Smectite clays can absorb water into clay inter-layers with the most important parameters being: the surface density of charge of the clay; the charge and solvation behaviour of the inter-layer ions; and the electrolyte concentration or activity of water. Two categories of swelling are generally observed: innercrystalline swelling caused by the hydration of the exchangeable cations in the dry clay; and osmotic swelling, resulting from concentration gradients in ion concentrations between clay surfaces and pore water. Several models exist to interpret and predict the swelling behaviour of clays. SKB currently prefer an interpretation of clay swelling pressure where clay particles are viewed as 'macro-ions' and the entire clay-water system can be considered as a 'polyelectrolyte'. SKB use the term 'Donnan exclusion' to estimate the amount of introduced ions into the clay and hence the amount of reduced swelling pressure due to contact with a saline solution. Donnan exclusion is the process whereby the migration of anions through the narrow aqueous film surrounding clay platelets is restricted due to the repulsion by the negative charge of the clay platelets. SKB's experimental work shows that: There is an exponential relation between swelling pressure and mean basal interlamellar spacing of the clay. Ions from the

Contact Resistance of Ceramic Interfaces Between Materials Used for Solid Oxide Fuel Cell Applications

DEFF Research Database (Denmark)

Koch, Søren

The contact resistance can be divided into two main contributions. The small area of contact between ceramic components results in resistance due to current constriction. Resistive phases or potential barriers at the interface result in an interface contribution to the contact resistance, which may....... The influence of the mechanical load on the contact resistance was ascribed to an area effect. The contact resistance of the investigated materials was dominated by current constric-tion at high temperatures. The measured contact resistance was comparable to the resis-tance calculated on basis of the contact...... areas found by optical and electron microscopy. At low temperatures, the interface contribution to the contact resistance was dominating. The cobaltite interface could be described by one potential barrier at the contact interface, whereas the manganite interfaces required several consecutive potential...

The technical supervision interface

CERN Document Server

Sollander, P

1998-01-01

The Technical Control Room (TCR) is currently using 30 different applications for the remote supervision of the technical infrastructure at CERN. These applications have all been developed with the CERN made Uniform Man Machine Interface (UMMI) tools built in 1990. However, the visualization technology has evolved phenomenally since 1990, the Technical Data Server (TDS) has radically changed our control system architecture, and the standardization and the maintenance of the UMMI applications have become important issues as their number increases. The Technical Supervision Interface is intended to replace the UMMI and solve the above problems. Using a standard WWW-browser for the display, it will be inherently multi-platform and hence available for control room operators, equipment specialists and on-call personnel.

Effects of interface electric field on the magnetoresistance in spin devices

Energy Technology Data Exchange (ETDEWEB)

Tanamoto, T., E-mail: tetsufumi.tanamoto@toshiba.co.jp; Ishikawa, M.; Inokuchi, T.; Sugiyama, H.; Saito, Y. [Advanced LSI Technology Laboratory Corporate Research and Development Center, Toshiba Corporation 1, Komukai Toshiba-cho, Saiwai-ku, Kawasaki 212-8582 (Japan)

2014-04-28

An extension of the standard spin diffusion theory is presented by using a quantum diffusion theory via a density-gradient (DG) term that is suitable for describing interface quantum tunneling phenomena. The magnetoresistance (MR) ratio is greatly modified by the DG term through an interface electric field. We have also carried out spin injection and detection measurements using four-terminal Si devices. The local measurement shows that the MR ratio changes depending on the current direction. We show that the change of the MR ratio depending on the current direction comes from the DG term regarding the asymmetry of the two interface electronic structures.

Fast Low-Current Spin-Orbit-Torque Switching of Magnetic Tunnel Junctions through Atomic Modifications of the Free-Layer Interfaces

Science.gov (United States)

Shi, Shengjie; Ou, Yongxi; Aradhya, S. V.; Ralph, D. C.; Buhrman, R. A.

2018-01-01

Future applications of spin-orbit torque will require new mechanisms to improve the efficiency of switching nanoscale magnetic tunnel junctions (MTJs), while also controlling the magnetic dynamics to achieve fast nanosecond-scale performance with low-write-error rates. Here, we demonstrate a strategy to simultaneously enhance the interfacial magnetic anisotropy energy and suppress interfacial spin-memory loss by introducing subatomic and monatomic layers of Hf at the top and bottom interfaces of the ferromagnetic free layer of an in-plane magnetized three-terminal MTJ device. When combined with a β -W spin Hall channel that generates spin-orbit torque, the cumulative effect is a switching current density of 5.4 ×106 A /cm2 .

International Expert Review of SRCan: Site Investigation Aspects. External review contribution in support of SKI's and SSI's review of SR-Can. INSITE/OVERSITE

International Nuclear Information System (INIS)

2008-03-01

As a first evaluation of long-term safety for KBS-3 repositories at Forsmark and Laxemar, the SIG (Site Investigation Group) found SR-Can to be a well-produced and generally well-argued safety assessment. Overall, SKB is to be complimented on this project. Members of of the two groups INSITE and OVERSITE within the SIG had somewhat differing views on how well SKB had made use of the site data available at the end of the SDM 1.2 stage of investigations. This difference is less to do with the extent of site characterisation than of its use and application, reflecting the different levels of maturity of SKB's geosphere and biosphere assessment programmes. The more recent and current work on the sites means that our concerns expressed in this review should, to a large extent, be addressable in or prior to SR-Site, provided SKB is so minded. However, we acknowledge that some of the issues we raise will not be fully resolved until underground rock characterisation from excavations or longer records of surface conditions are available. There are also some key aspects of SKB's methodology still under development that would benefit from review prior to their use in SR-Site. More space in the currently pressing schedule would allow for this review and a consequent increase in confidence. In any case, the authorities should be aware that SKB may face residual programmatic risks, associated principally with the underground design and layout (and their knockon effects into performance), even after SR-Site. An early understanding of some of these relationships would be helped by a plan (at least on an outline level) of the underground characterisation programme. We also note that many engineering matters are still to be confronted, not least the EBS design and its implementation, along with the treatment of high stresses, if Forsmark is selected. However, our views on the nature of the SR-Can analysis and the way in which site data have been utilised in it (our principal remit

High thermal stability of abrupt SiO2/GaN interface with low interface state density

Science.gov (United States)

Truyen, Nguyen Xuan; Taoka, Noriyuki; Ohta, Akio; Makihara, Katsunori; Yamada, Hisashi; Takahashi, Tokio; Ikeda, Mitsuhisa; Shimizu, Mitsuaki; Miyazaki, Seiichi

2018-04-01

The effects of postdeposition annealing (PDA) on the interface properties of a SiO2/GaN structure formed by remote oxygen plasma-enhanced chemical vapor deposition (RP-CVD) were systematically investigated. X-ray photoelectron spectroscopy clarified that PDA in the temperature range from 600 to 800 °C has almost no effects on the chemical bonding features at the SiO2/GaN interface, and that positive charges exist at the interface, the density of which can be reduced by PDA at 800 °C. The capacitance-voltage (C-V) and current density-SiO2 electric field characteristics of the GaN MOS capacitors also confirmed the reduction in interface state density (D it) and the improvement in the breakdown property of the SiO2 film after PDA at 800 °C. Consequently, a high thermal stability of the SiO2/GaN structure with a low fixed charge density and a low D it formed by RP-CVD was demonstrated. This is quite informative for realizing highly robust GaN power devices.

Theory of bulk and interface constant phase elements in electrode- electrolyte systems

International Nuclear Information System (INIS)

Liu, S.H.

1991-01-01

This paper summarizes the progress gained in the last few years in our understanding of bulk and interface constant-phase-angle (CPA) behavior in electrode-electrolyte systems. It is now fairly well established that the interface constant-phase element originates from the fractal nature of the interface. The complex geometry gives rise to a fractal distribution of parallel current paths, and the competition between these paths results in the fractional power law behavior of the impedance across the interface. On the other hand, the early hope of relating the CPA exponent to the fractal dimension of the interface has been shown to be unattainable. Our understanding of the bulk CPA behavior, which is most prevalent in solid electrolytes, is only tentative. It is illustrated using a simple model that, under nonlinear dynamical laws that govern the flow of ions in the electrolyte, a current in the solid can generate a fractal distribution of vacancies which tend to impede the flow. The current is forced to negotiate a complex path through the solid, and the resulting fluctuation in path length and flow rate could be a source of the CPA behavior. 32 refs., 18 figs

Research of Digital Interface Layout Design based on Eye-tracking

OpenAIRE

Shao Jiang; Xue Chengqi; Wang Fang; Wang Haiyan; Tang Wencheng; Chen Mo; Kang Mingwu

2015-01-01

The aim of this paper is to improve the low service efficiency and unsmooth human-computer interaction caused by currently irrational layouts of digital interfaces for complex systems. Also, three common layout structures for digital interfaces are to be presented and five layout types appropriate for multilevel digital interfaces are to be summarized. Based on the eye tracking technology, an assessment was conducted in advantages and disadvantages of different layout types through subjects’ ...

A meta-analysis of human-system interfaces in unmanned aerial vehicle (UAV) swarm management.

Science.gov (United States)

Hocraffer, Amy; Nam, Chang S

2017-01-01

A meta-analysis was conducted to systematically evaluate the current state of research on human-system interfaces for users controlling semi-autonomous swarms composed of groups of drones or unmanned aerial vehicles (UAVs). UAV swarms pose several human factors challenges, such as high cognitive demands, non-intuitive behavior, and serious consequences for errors. This article presents findings from a meta-analysis of 27 UAV swarm management papers focused on the human-system interface and human factors concerns, providing an overview of the advantages, challenges, and limitations of current UAV management interfaces, as well as information on how these interfaces are currently evaluated. In general allowing user and mission-specific customization to user interfaces and raising the swarm's level of autonomy to reduce operator cognitive workload are beneficial and improve situation awareness (SA). It is clear more research is needed in this rapidly evolving field. Copyright © 2016 Elsevier Ltd. All rights reserved.

Critical interfaces in geosynthetic multilayer liner system of a landfill

Directory of Open Access Journals (Sweden)

Qian Xuede

2008-12-01

Full Text Available This study is to identify the critical interface in a geosynthetic multilayer liner system by examining the effects of the interface shear strength of liner components, leachate level, leachate buildup cases, and peak and residual interface strengths. According to current landfill design procedures, conducting stability analysis along the same interface at both the back slope and base may result in a non-conservative result. The critical interfaces with the minimum factor of safety are generally found at different locations along the back slope and base. The critical interface for a multilayer liner system cannot simply be assumed during stability analysis. It can shift from one interface to another with changes in the leachate level and with different leachate buildup cases. The factor of safety for an interface with a high friction angle and low apparent cohesion generally drops much more quickly than it does under inverse conditions when the leachate level increases. The failure interface in a liner system under residual conditions is usually different from the failure interface under peak conditions.

A Critique on the Effectiveness of Current Human Reliability Analysis Approach for the Human-Machine Interface Design in Nuclear Power Plants

International Nuclear Information System (INIS)

Lee, Yong Hee

2010-01-01

Human Reliability Analysis (HRA) in cooperation of PSA has been conducted to evaluate the safety of a system and the validity of a system design. HRA has been believed to provide a quantitative value of human error potential and the safety level of a design alternative in Nuclear Power Plants (NPPs). However, it becomes doubtful that current HRA is worth to conduct to evaluate the human factors of NPP design, since there have been many critiques upon the virtue of HRA. Inevitably, the newer the technology becomes, the larger endeavors bound for the new facilitated methods. This paper describes the limitations and the obsolescence of the current HRA, especially for the design evaluation of Human-Machine Interface (HMI) utilizing the recent digital technologies. An alternative approach to the assessment of the human error potential of HMI design is proposed

Kinetic Interface

DEFF Research Database (Denmark)

2009-01-01

A kinetic interface for orientation detection in a video training system is disclosed. The interface includes a balance platform instrumented with inertial motion sensors. The interface engages a participant's sense of balance in training exercises.......A kinetic interface for orientation detection in a video training system is disclosed. The interface includes a balance platform instrumented with inertial motion sensors. The interface engages a participant's sense of balance in training exercises....

Bubble bursting at an interface

Science.gov (United States)

Kulkarni, Varun; Sajjad, Kumayl; Anand, Sushant; Fezzaa, Kamel

2017-11-01

Bubble bursting is crucial to understanding the life span of bubbles at an interface and more importantly the nature of interaction between the bulk liquid and the outside environment from the point of view of chemical and biological material transport. The dynamics of the bubble as it rises from inside the liquid bulk to its disappearance on the interface after bursting is an intriguing process, many aspects of which are still being explored. In our study, we make detailed high speed imaging measurements to examine carefully the hole initiation and growth in bursting bubbles that unearth some interesting features of the process. Previous analyses available in literature are revisited based on our novel experimental visualizations. Using a combination of experiments and theory we investigate the role of various forces during the rupturing process. This work aims to further our current knowledge of bubble dynamics at an interface with an aim of predicting better the bubble evolution from its growth to its eventual integration with the liquid bulk.

TaskMaster: a prototype graphical user interface to a schedule optimization model

OpenAIRE

Banham, Stephen R.

1990-01-01

Approved for public release, distribution is unlimited This thesis investigates the use of current graphical interface techniques to build more effective computer-user interfaces to Operations Research (OR) schedule optimization models. The design is directed at the scheduling decision maker who possesses limited OR experience. The feasibility and validity of building an interface for this kind of user is demonstrated in the development of a prototype graphical user interface called TaskMa...

Radionuclide Transport Modelling: Current Status and Future Needs. Synthesis, Work Group Reports and Extended Abstracts

International Nuclear Information System (INIS)

2002-06-01

The workshop identified a set of critical issues for the Swedish Nuclear Power Inspectorate (SKI) and the Swedish Radiation Protection Authority (SSI) to address in preparing for future reviews of license applications, which have subsequently been considered in preparing this synthesis. Structure for organising expert participation: A structure for organising expert participation in future reviews is proposed based on clearinghouses for (1) regulatory application and context, (2) engineered barrier systems, (3) geosphere, (4) biosphere, and (5) performance assessment integration and calculations. As part of their work, these clearinghouses could identify key issues that need to be resolved prior to future reviews. Performance assessment strategy and review context: Future reviews will be conducted in the context of regulations based on risk criteria; this leads to a need to review the methods used in probabilistic risk assessment, as well as the underlying process models. A plan is needed for accomplishing both aims. Despite the probabilistic framework, a need is anticipated for targeted, deterministic calculations to check particular assumptions. Priorities and ambition level for reviews: SKI's and SSI's resources can be more efficiently utilised by an early review of SKB's safety case, so that if necessary the authorities can make an early start on evaluating topics that are of primary significance to the safety case. As a guide to planning for allocation of effort in future reviews, this workshop produced a preliminary ranking of technical issues, on a scale from 'non-controversial' to 'requiring independent modelling,' Analysis of repository system and scenarios: Systems analysis tools including features/events/processes encyclopaedias, process-influence diagrams, and assessment-model flowcharts should be used as review tools, to check the processes and influences considered in SKB's analyses, and to evaluate the comprehensiveness of the scenarios that are

Radionuclide Transport Modelling: Current Status and Future Needs. Synthesis, Work Group Reports and Extended Abstracts

Energy Technology Data Exchange (ETDEWEB)

NONE

2002-06-01

The workshop identified a set of critical issues for the Swedish Nuclear Power Inspectorate (SKI) and the Swedish Radiation Protection Authority (SSI) to address in preparing for future reviews of license applications, which have subsequently been considered in preparing this synthesis. Structure for organising expert participation: A structure for organising expert participation in future reviews is proposed based on clearinghouses for (1) regulatory application and context, (2) engineered barrier systems, (3) geosphere, (4) biosphere, and (5) performance assessment integration and calculations. As part of their work, these clearinghouses could identify key issues that need to be resolved prior to future reviews. Performance assessment strategy and review context: Future reviews will be conducted in the context of regulations based on risk criteria; this leads to a need to review the methods used in probabilistic risk assessment, as well as the underlying process models. A plan is needed for accomplishing both aims. Despite the probabilistic framework, a need is anticipated for targeted, deterministic calculations to check particular assumptions. Priorities and ambition level for reviews: SKI's and SSI's resources can be more efficiently utilised by an early review of SKB's safety case, so that if necessary the authorities can make an early start on evaluating topics that are of primary significance to the safety case. As a guide to planning for allocation of effort in future reviews, this workshop produced a preliminary ranking of technical issues, on a scale from 'non-controversial' to 'requiring independent modelling,' Analysis of repository system and scenarios: Systems analysis tools including features/events/processes encyclopaedias, process-influence diagrams, and assessment-model flowcharts should be used as review tools, to check the processes and influences considered in SKB's analyses, and to evaluate the comprehensiveness of the scenarios that are

Man-machine interface requirements - advanced technology

Science.gov (United States)

Remington, R. W.; Wiener, E. L.

1984-01-01

Research issues and areas are identified where increased understanding of the human operator and the interaction between the operator and the avionics could lead to improvements in the performance of current and proposed helicopters. Both current and advanced helicopter systems and avionics are considered. Areas critical to man-machine interface requirements include: (1) artificial intelligence; (2) visual displays; (3) voice technology; (4) cockpit integration; and (5) pilot work loads and performance.

The Swedish radiological environmental protection regulations applied in a review of a license application for a geological repository for spent nuclear fuel.

Science.gov (United States)

Andersson, Pål; Stark, Karolina; Xu, Shulan; Nordén, Maria; Dverstorp, Björn

2017-11-01

For the first time, a system for specific consideration of radiological environmental protection has been applied in a major license application in Sweden. In 2011 the Swedish Nuclear Fuel & Waste Management Co. (SKB) submitted a license application for construction of a geological repository for spent nuclear fuel at the Forsmark site. The license application is supported by a post-closure safety assessment, which in accordance with regulatory requirements includes an assessment of environmental consequences. SKB's environmental risk assessment uses the freely available ERICA Tool. Environmental media activity concentrations needed as input to the tool are calculated by means of complex biosphere modelling based on site-specific information gathered from site investigations, as well as from supporting modelling studies and projections of future biosphere conditions in response to climate change and land rise due to glacial rebound. SKB's application is currently being reviewed by the Swedish Radiation Safety Authority (SSM). In addition to a traditional document review with an aim to determine whether SKB's models are relevant, correctly implemented and adequately parametrized, SSM has performed independent modelling in order to gain confidence in the robustness of SKB's assessment. Thus, SSM has used alternative stylized reference biosphere models to calculate environmental activity concentrations for use in subsequent exposure calculations. Secondly, an alternative dose model (RESRAD-BIOTA) is used to calculate doses to biota that are compared with SKB's calculations with the ERICA tool. SSM's experience from this review is that existing tools for environmental dose assessment are possible to use in order to show compliance with Swedish legislation. However, care is needed when site representative species are assessed with the aim to contrast them to generic reference organism. The alternative modelling of environmental concentrations resulted in much lower

New Year, new interface for EDMS!

CERN Multimedia

2015-01-01

Some of you may already have made the leap to the new EDMS6 interface and be benefitting from the additional functionality and new design it has to offer. But for those who haven’t, you will be able to do so as of Wednesday 28 January when EDMS6 becomes the default interface.    EDMS is the de facto interface for all engineering related data and more. There are currently more than 1.5 million documents and over 2 million files stored there. What’s new in EDMS6? While we have kept the key concepts, we have introduced more functionality and improved navigation within the interface, allowing for better performance to help you in your daily work. We have also added a personal slant to EDMS6 so that you can now customise your list of favourite objects. Modifying data in EDMS is much simpler, allowing you to view all object data in a single window. For example, files can be added to documents with a simple drag and drop and you can now request access to documents...

Brookhaven fastbus/unibus interface

International Nuclear Information System (INIS)

Benenson, G.; Bauernfeind, J.; Larsen, R.C.

1983-01-01

A typical high energy physics experiment requires both a high speed data acquisition and processing system, for data collection and reduction; and a general purpose computer to handle further reduction, bookkeeping and mass storage. Broad differences in architecture, format or technology, will often exist between these two systems, and interface design can become a formidable task. The PDP-11 series minicomputer is widely used in physics research, and the Brookhaven FASTBUS is the only standard high speed data acquisition system which is fully implemented in a current high energy physics experiment. This paper will describe the design and operation of an interface between these two systems. The major issues are elucidated by a preliminary discussion on the basic principles of Bus Systems, and their application to Brookhaven FASTBUS and UNIBUS

Internal Interface Diversification as a Security Measure in Sensor Networks

Directory of Open Access Journals (Sweden)

Sampsa Rauti

2018-03-01

Full Text Available More actuator and sensor devices are connected to the Internet of Things (IoT every day, and the network keeps growing, while software security of the devices is often incomplete. Sensor networks and the IoT in general currently cover a large number of devices with an identical internal interface structure. By diversifying the internal interfaces, the interfaces on each node of the network are made unique, and it is possible to break the software monoculture of easily exploitable identical systems. This paper proposes internal interface diversification as a security measure for sensor networks. We conduct a study on diversifiable internal interfaces in 20 IoT operating systems. We also present two proof-of-concept implementations and perform experiments to gauge the feasibility in the IoT environment. Internal interface diversification has practical limitations, and not all IoT operating systems have that many diversifiable interfaces. However, because of low resource requirements, compatibility with other security measures and wide applicability to several interfaces, we believe internal interface diversification is a promising and effective approach for securing nodes in sensor networks.

Web OPAC Interfaces: An Overview.

Science.gov (United States)

Babu, B. Ramesh; O'Brien, Ann

2000-01-01

Discussion of Web-based online public access catalogs (OPACs) focuses on a review of six Web OPAC interfaces in use in academic libraries in the United Kingdom. Presents a checklist and guidelines of important features and functions that are currently available, including search strategies, access points, display, links, and layout. (Author/LRW)

Brain-machine and brain-computer interfaces.

Science.gov (United States)

Friehs, Gerhard M; Zerris, Vasilios A; Ojakangas, Catherine L; Fellows, Mathew R; Donoghue, John P

2004-11-01

The idea of connecting the human brain to a computer or machine directly is not novel and its potential has been explored in science fiction. With the rapid advances in the areas of information technology, miniaturization and neurosciences there has been a surge of interest in turning fiction into reality. In this paper the authors review the current state-of-the-art of brain-computer and brain-machine interfaces including neuroprostheses. The general principles and requirements to produce a successful connection between human and artificial intelligence are outlined and the authors' preliminary experience with a prototype brain-computer interface is reported.

Interface tracking for 2D hydrodynamics

International Nuclear Information System (INIS)

Bezard, Fabienne

1997-01-01

The aim of this work is to explore new methods to numerically simulate the evolution of interfaces between immiscible fluids in the context of the dynamics of compressible and non-viscous fluids. The methods currently available, to our knowledge, to deal with this type of problem are based on the Lagrange coordinates (that is to say, that follow the material in its displacements) or on the Euler coordinates (fixed during the time). In the case of Eulerian coordinates, the simplest methods involve so-called 'mixing' meshes (that is, containing several fluids). The study that is presented is based on an Eulerian method with Lagrangian interface tracking. This avoids the introduction of any model of mesh of mixture. This method combines some advantages of the previously mentioned methods, notably the precision of the Lagrangian follow-up and the robustness of the Eulerian schemes. This report describes only the algorithms of displacement and regularization of the interface, by clearly presenting the geometry around the interface. These algorithms will then be coupled with the resolution of two-dimensional hydrodynamic equations to solve multi-fluid problems. Some numerical results are proposed to illustrate the good behavior of the interface tracking algorithm [fr

Microscopic theory of the current-voltage relationship across a normal-superconducting interface

International Nuclear Information System (INIS)

Kraehenbuehl, Y.; Watts-Tobin, R.J.

1979-01-01

Measurements by Pippard et al. have shown the existence of an extra resistance due to the penetration of an electrical potential into a superconductor. Previous theories of this effect are unable to explain the full temperature dependence of the extra resistance because they use oversimplified models of the normal--superconducting interface. We show that the microscopic theory for dirty superconductors leads to a good agreement with experiment over the whole temperature range

What limits the performance of current invasive Brain Machine Interfaces?

Directory of Open Access Journals (Sweden)

Gytis eBaranauskas

2014-04-01

Full Text Available The concept of a brain-machine interface (BMI or a computer-brain interface is simple: BMI creates a communication pathway for a direct control by brain of an external device. In reality BMIs are very complex devices and only recently the increase in computing power of microprocessors enabled a boom in BMI research that continues almost unabated to this date, the high point being the insertion of electrode arrays into the brains of 5 human patients in a clinical trial run by Cyberkinetics with few other clinical tests still in progress. Meanwhile several EEG-based BMI devices (non-invasive BMIs were launched commercially. Modern electronics and dry electrode technology made possible to drive the cost of some of these devices below few hundred dollars. However, the initial excitement of the direct control by brain waves of a computer or other equipment is dampened by large efforts required for learning, high error rates and slow response speed. All these problems are directly related to low information transfer rates typical for such EEG-based BMIs. In invasive BMIs employing multiple electrodes inserted into the brain one may expect much higher information transfer rates than in EEG-based BMIs because, in theory, each electrode provides an independent information channel. However, although invasive BMIs require more expensive equipment and have ethical problems related to the need to insert electrodes in the live brain, such financial and ethical costs are often not offset by a dramatic improvement in the information transfer rate. Thus the main topic of this review is why in invasive BMIs an apparently much larger information content obtained with multiple extracellular electrodes does not translate into much higher rates of information transfer? This paper explores possible answers to this question by concluding that more research on what movement parameters are encoded by neurons in motor cortex is needed before we can enjoy the next

The Integrated Mode Management Interface

Science.gov (United States)

Hutchins, Edwin

1996-01-01

Mode management is the processes of understanding the character and consequences of autoflight modes, planning and selecting the engagement, disengagement and transitions between modes, and anticipating automatic mode transitions made by the autoflight system itself. The state of the art is represented by the latest designs produced by each of the major airframe manufacturers, the Boeing 747-400, the Boeing 777, the McDonnell Douglas MD-11, and the Airbus A320/A340 family of airplanes. In these airplanes autoflight modes are selected by manipulating switches on the control panel. The state of the autoflight system is displayed on the flight mode annunciators. The integrated mode management interface (IMMI) is a graphical interface to autoflight mode management systems for aircraft equipped with flight management computer systems (FMCS). The interface consists of a vertical mode manager and a lateral mode manager. Autoflight modes are depicted by icons on a graphical display. Mode selection is accomplished by touching (or mousing) the appropriate icon. The IMMI provides flight crews with an integrated interface to autoflight systems for aircraft equipped with flight management computer systems (FMCS). The current version is modeled on the Boeing glass-cockpit airplanes (747-400, 757/767). It runs on the SGI Indigo workstation. A working prototype of this graphics-based crew interface to the autoflight mode management tasks of glass cockpit airplanes has been installed in the Advanced Concepts Flight Simulator of the CSSRF of NASA Ames Research Center. This IMMI replaces the devices in FMCS equipped airplanes currently known as mode control panel (Boeing), flight guidance control panel (McDonnell Douglas), and flight control unit (Airbus). It also augments the functions of the flight mode annunciators. All glass cockpit airplanes are sufficiently similar that the IMMI could be tailored to the mode management system of any modern cockpit. The IMMI does not replace the

Contact resistance of ceramic interfaces between materials used for solid oxide fuel cell applications

Energy Technology Data Exchange (ETDEWEB)

Koch, S.

2002-01-01

The contact resistance can be divided into two main contributions. The small area of contact between ceramic components results in resistance due to current constriction. Resistive phases or potential barriers at the interface result in an interface contribution to the contact resistance, which may be smaller or larger than the constriction resistance. The contact resistance between pairs of three different materials were analysed (strontium doped lanthanum manganite, yttria stabilised zirconia and strontium and nickel doped lanthanum cobaltite), and the effects of temperature, atmosphere, polarisation and mechanical load on the contact resistance were investigated. The investigations revealed that the mechanical load of a ceramic contact has a high influence on the contact resistance, and generally power law dependence between the contact resistance and the mechanical load was found. The influence of the mechanical load on the contact resistance was ascribed to an area effect. The contact resistance of the investigated materials was dominated by current constriction at high temperatures. The measured contact resistance was comparable to the resistance calculated on basis of the contact areas found by optical and electron microscopy. At low temperatures, the interface contribution to the contact resistance was dominating. The cobaltite interface could be described by one potential barrier at the contact interface, whereas the manganite interfaces required several consecutive potential barriers to model the observed behaviour. The current-voltage behaviour of the YSZ contact interfaces was only weakly non-linear, and could be described by 22{+-}1 barriers in series. Contact interfaces with sinterable contact layers were also investigated, and the measured contact resistance for these interfaces were more than 10 times less than for the other interfaces. (au)

Flaws in current human training protocols for spontaneous Brain-Computer Interfaces: lessons learned from instructional design

Directory of Open Access Journals (Sweden)

Fabien eLotte

2013-09-01

Full Text Available While recent research on Brain-Computer Interfaces (BCI has highlighted their potential for many applications, they remain barely used outside laboratories. The main reason is their lack of robustness. Indeed, with current BCI, mental state recognition is usually slow and often incorrect. Spontaneous BCI (i.e., mental imagery-based BCI often rely on mutual learning efforts by the user and the machine, with BCI users learning to produce stable EEG patterns (spontaneous BCI control being widely acknowledged as a skill while the computer learns to automatically recognize these EEG patterns, using signal processing. Most research so far was focused on signal processing, mostly neglecting the human in the loop. However, how well the user masters the BCI skill is also a key element explaining BCI robustness. Indeed, if the user is not able to produce stable and distinct EEG patterns, then no signal processing algorithm would be able to recognize them. Unfortunately, despite the importance of BCI training protocols, they have been scarcely studied so far, and used mostly unchanged for years.In this paper, we advocate that current human training approaches for spontaneous BCI are most likely inappropriate. We notably study instructional design literature in order to identify the key requirements and guidelines for a successful training procedure that promotes a good and efficient skill learning. This literature study highlights that current spontaneous BCI user training procedures satisfy very few of these requirements and hence are likely to be suboptimal. We therefore identify the flaws in BCI training protocols according to instructional design principles, at several levels: in the instructions provided to the user, in the tasks he/she has to perform, and in the feedback provided. For each level, we propose new research directions that are theoretically expected to address some of these flaws and to help users learn the BCI skill more efficiently.

Critical current of pure SNS junctions

International Nuclear Information System (INIS)

Golub, A.A.; Bezzub, O.P.

1982-01-01

Boundary conditions at the superconductor-normal metal interface are determined, taking into account the differences in the effective masses and the density of states of the metals constituting the transition and assumed to be pure. The potential barrier of the interface is chosen to be zero. The critical current of the junction is calculated [ru

Current-induced switching in a magnetic insulator

Science.gov (United States)

Avci, Can Onur; Quindeau, Andy; Pai, Chi-Feng; Mann, Maxwell; Caretta, Lucas; Tang, Astera S.; Onbasli, Mehmet C.; Ross, Caroline A.; Beach, Geoffrey S. D.

2017-03-01

The spin Hall effect in heavy metals converts charge current into pure spin current, which can be injected into an adjacent ferromagnet to exert a torque. This spin-orbit torque (SOT) has been widely used to manipulate the magnetization in metallic ferromagnets. In the case of magnetic insulators (MIs), although charge currents cannot flow, spin currents can propagate, but current-induced control of the magnetization in a MI has so far remained elusive. Here we demonstrate spin-current-induced switching of a perpendicularly magnetized thulium iron garnet film driven by charge current in a Pt overlayer. We estimate a relatively large spin-mixing conductance and damping-like SOT through spin Hall magnetoresistance and harmonic Hall measurements, respectively, indicating considerable spin transparency at the Pt/MI interface. We show that spin currents injected across this interface lead to deterministic magnetization reversal at low current densities, paving the road towards ultralow-dissipation spintronic devices based on MIs.

Spin current

CERN Document Server

Valenzuela, Sergio O; Saitoh, Eiji; Kimura, Takashi

2017-01-01

Since the discovery of the giant magnetoresistance effect in magnetic multilayers in 1988, a new branch of physics and technology, called spin-electronics or spintronics, has emerged, where the flow of electrical charge as well as the flow of electron spin, the so-called “spin current,” are manipulated and controlled together. The physics of magnetism and the application of spin current have progressed in tandem with the nanofabrication technology of magnets and the engineering of interfaces and thin films. This book aims to provide an introduction and guide to the new physics and applications of spin current, with an emphasis on the interaction between spin and charge currents in magnetic nanostructures.

Plan 2010. Costs starting in 2012 for the radioactive residual products from nuclear power. Basis for fees and guarantees during the period 2012-2014

Energy Technology Data Exchange (ETDEWEB)

2010-12-15

According to the current regulatory framework, it is the responsibility of the holder of a licence to own or operate a nuclear power reactor to prepare a calculation of the costs for all measures that are needed for the management and disposal of spent nuclear fuel that has been used in the reactors and other radioactive waste products and to decommission and dismantle the reactor plants. The regulatory framework comprises the Act (2006:647) and the Ordinance (2008:715) on Financial Measures for the Management of Residual Products from Nuclear Activities (hereinafter referred to as the Financing Act and the Financing Ordinance, respectively). This cost calculation shall be submitted periodically to the Government or the authority designated by the Government. SKB's owners have assigned SKB the task of preparing such a cost calculation jointly for the licensees of the Swedish nuclear power plants. The present report, which is the twenty-eighth annual plan report, gives an updated compilation of these costs. As in previous years' reports, the costs are shown for two cases. The first case concerns the system as a whole, including management and disposal of radioactive operational waste plus certain waste deriving from other facilities than those belonging to SKB's owners. This case has been based on a scenario concerning reactor operation that is based on the nuclear power plant owners' current planning. The second case concerns the system with the restrictions that follow from the regulatory framework, which stipulates the time for operation of the reactors that is supposed to serve as a basis for fees. The report is divided into three parts: Chapter 1 provides background information regarding the Financing Act and SKB's calculation model. Chapter 2 provides information on the underlying calculation, which is based on current plans for reactor operation and SKB's activities. Chapter 3 presents the cost estimates required by the Financing

Plan 2010. Costs starting in 2012 for the radioactive residual products from nuclear power. Basis for fees and guarantees during the period 2012-2014

International Nuclear Information System (INIS)

2010-12-01

According to the current regulatory framework, it is the responsibility of the holder of a licence to own or operate a nuclear power reactor to prepare a calculation of the costs for all measures that are needed for the management and disposal of spent nuclear fuel that has been used in the reactors and other radioactive waste products and to decommission and dismantle the reactor plants. The regulatory framework comprises the Act (2006:647) and the Ordinance (2008:715) on Financial Measures for the Management of Residual Products from Nuclear Activities (hereinafter referred to as the Financing Act and the Financing Ordinance, respectively). This cost calculation shall be submitted periodically to the Government or the authority designated by the Government. SKB's owners have assigned SKB the task of preparing such a cost calculation jointly for the licensees of the Swedish nuclear power plants. The present report, which is the twenty-eighth annual plan report, gives an updated compilation of these costs. As in previous years' reports, the costs are shown for two cases. The first case concerns the system as a whole, including management and disposal of radioactive operational waste plus certain waste deriving from other facilities than those belonging to SKB's owners. This case has been based on a scenario concerning reactor operation that is based on the nuclear power plant owners' current planning. The second case concerns the system with the restrictions that follow from the regulatory framework, which stipulates the time for operation of the reactors that is supposed to serve as a basis for fees. The report is divided into three parts: Chapter 1 provides background information regarding the Financing Act and SKB's calculation model. Chapter 2 provides information on the underlying calculation, which is based on current plans for reactor operation and SKB's activities. Chapter 3 presents the cost estimates required by the Financing Act that are the primary

Knowledge-based control of an adaptive interface

Science.gov (United States)

Lachman, Roy

1989-01-01

The analysis, development strategy, and preliminary design for an intelligent, adaptive interface is reported. The design philosophy couples knowledge-based system technology with standard human factors approaches to interface development for computer workstations. An expert system has been designed to drive the interface for application software. The intelligent interface will be linked to application packages, one at a time, that are planned for multiple-application workstations aboard Space Station Freedom. Current requirements call for most Space Station activities to be conducted at the workstation consoles. One set of activities will consist of standard data management services (DMS). DMS software includes text processing, spreadsheets, data base management, etc. Text processing was selected for the first intelligent interface prototype because text-processing software can be developed initially as fully functional but limited with a small set of commands. The program's complexity then can be increased incrementally. The intelligent interface includes the operator's behavior and three types of instructions to the underlying application software are included in the rule base. A conventional expert-system inference engine searches the data base for antecedents to rules and sends the consequents of fired rules as commands to the underlying software. Plans for putting the expert system on top of a second application, a database management system, will be carried out following behavioral research on the first application. The intelligent interface design is suitable for use with ground-based workstations now common in government, industrial, and educational organizations.

Improvement of computer complex and interface system for compact nuclear simulator

International Nuclear Information System (INIS)

Lee, D. Y.; Park, W. M.; Cha, K. H.; Jung, C. H.; Park, J. C.

1999-01-01

CNS(Compact Nuclear Simulator) was developed at the end of 1980s, and have been used as training simulator for staffs of KAERI during 10 years. The operator panel interface cards and the graphic interface cards were designed with special purpose only for CNS. As these interface cards were worn out for 10 years, it was very difficult to get spare parts and to repair them. And the interface cards were damaged by over current happened by shortage of lamp in the operator panel. To solve these problem, the project 'Improvement of Compact Nuclear Simulator' was started from 1997. This paper only introduces about the improvement of computer complex and interface system

Working paper 'Using the benefits of the subsoil'; Discussiestuk 'Benutten van de baten van de ondergrond'

Energy Technology Data Exchange (ETDEWEB)

Duijn, M.; Ellen, G.J.; Jonkhoff, W.; Reijs, T.

2009-04-15

SKB, The Dutch Centre for Soil Quality Management and Knowledge Transfer, is currently establishing a new development program addressing four social issues: (1) (ground)water management, (2) geothermal energy, (3) ecosystem services, and (4) benefits of sustainable development of the subsoil. [Dutch] SKB is momenteel bezig een nieuw ontwikkelingsprogramma op te zetten rondom vier maatschappelijke issues: (1) (grond) waterbeheer, (2) bodem-energie, (3) ecosysteem-diensten, en (4) ondergronds ruimtegebruik. Voor deze issues worden de (potentiele) baten van een duurzame ontwikkeling van de ondergrond in beeld gebracht.

Benefits of the subsoil; Baten van de ondergrond

Energy Technology Data Exchange (ETDEWEB)

Duijn, M.; Ellen, G.J.; Jonkhoff, W.; Reijs, T.

2009-05-15

SKB, The Dutch Centre for Soil Quality Management and Knowledge Transfer, is currently establishing a new development program addressing four social issues: (1) (ground)water management, (2) geothermal energy, (3) ecosystem services, and (4) benefits of sustainable development of the subsoil [Dutch] SKB is momenteel bezig een nieuw ontwikkelingsprogramma op te zetten rondom vier maatschappelijke issues: (1) (grond) waterbeheer, (2) bodem-energie, (3) ecosysteem-diensten, en (4) ondergronds ruimtegebruik. Voor deze issues worden de (potentiele) baten van een duurzame ontwikkeling van de ondergrond in beeld gebracht.

Description of surface systems. Preliminary site description Simpevarp sub area - Version 1.2

Energy Technology Data Exchange (ETDEWEB)

Lindborg, Tobias [ed.

2005-03-01

Swedish Nuclear Fuel and Waste Management Co is currently conducting site characterisation in the Simpevarp area. The area is divided into two subareas, the Simpevarp and the Laxemar subarea. The two subareas are surrounded by a common regional model area, the Simpevarp area. This report describes both the regional area and the subareas. This report is an interim version (model version 1.2) of the description of the surface systems at the Simpevarp area, and should be seen as a background report to the site description of the Simpevarp area, version 1.2, SKB-R--05-08. The basis for this description is quality-assured field data available in the SKB SICADA and GIS databases, together with generic data from the literature. The Surface system, here defined as everything above the bedrock, comprises a number of separate disciplines (e.g. hydrology, geology, topography, oceanography and ecology). Each discipline has developed descriptions and models for a number of properties that together represent the site description. The current methodology for developing the surface system description and the integration to ecosystem models is documented in a methodology strategy report SKB-R--03-06. The procedures and guidelines given in that report were followed in this report. Compared with version 1.1 of the surface system description SKB-R--04-25, this report presents considerable additional features, especially in the ecosystem description (Chapter 4) and in the description of the surface hydrology (Section 3.4). A first attempt has also been made to connect the flow of matter (carbon) between the different ecosystems into an overall ecosystem model at a landscape level. A summarised version of this report is also presented in SKB-R--05-08 together with geological-, hydrogeological-, transport properties-, thermal properties-, rock mechanics- and hydrogeochemical descriptions.

Description of surface systems. Preliminary site description Simpevarp sub area - Version 1.2

International Nuclear Information System (INIS)

Lindborg, Tobias

2005-03-01

Swedish Nuclear Fuel and Waste Management Co is currently conducting site characterisation in the Simpevarp area. The area is divided into two subareas, the Simpevarp and the Laxemar subarea. The two subareas are surrounded by a common regional model area, the Simpevarp area. This report describes both the regional area and the subareas. This report is an interim version (model version 1.2) of the description of the surface systems at the Simpevarp area, and should be seen as a background report to the site description of the Simpevarp area, version 1.2, SKB-R--05-08. The basis for this description is quality-assured field data available in the SKB SICADA and GIS databases, together with generic data from the literature. The Surface system, here defined as everything above the bedrock, comprises a number of separate disciplines (e.g. hydrology, geology, topography, oceanography and ecology). Each discipline has developed descriptions and models for a number of properties that together represent the site description. The current methodology for developing the surface system description and the integration to ecosystem models is documented in a methodology strategy report SKB-R--03-06. The procedures and guidelines given in that report were followed in this report. Compared with version 1.1 of the surface system description SKB-R--04-25, this report presents considerable additional features, especially in the ecosystem description (Chapter 4) and in the description of the surface hydrology (Section 3.4). A first attempt has also been made to connect the flow of matter (carbon) between the different ecosystems into an overall ecosystem model at a landscape level. A summarised version of this report is also presented in SKB-R--05-08 together with geological-, hydrogeological-, transport properties-, thermal properties-, rock mechanics- and hydrogeochemical descriptions

International Expert Review of SRCan: Site Investigation Aspects. External review contribution in support of SKI's and SSI's review of SR-Can. INSITE/OVERSITE

Energy Technology Data Exchange (ETDEWEB)

2008-03-15

As a first evaluation of long-term safety for KBS-3 repositories at Forsmark and Laxemar, the SIG (Site Investigation Group) found SR-Can to be a well-produced and generally well-argued safety assessment. Overall, SKB is to be complimented on this project. Members of of the two groups INSITE and OVERSITE within the SIG had somewhat differing views on how well SKB had made use of the site data available at the end of the SDM 1.2 stage of investigations. This difference is less to do with the extent of site characterisation than of its use and application, reflecting the different levels of maturity of SKB's geosphere and biosphere assessment programmes. The more recent and current work on the sites means that our concerns expressed in this review should, to a large extent, be addressable in or prior to SR-Site, provided SKB is so minded. However, we acknowledge that some of the issues we raise will not be fully resolved until underground rock characterisation from excavations or longer records of surface conditions are available. There are also some key aspects of SKB's methodology still under development that would benefit from review prior to their use in SR-Site. More space in the currently pressing schedule would allow for this review and a consequent increase in confidence. In any case, the authorities should be aware that SKB may face residual programmatic risks, associated principally with the underground design and layout (and their knockon effects into performance), even after SR-Site. An early understanding of some of these relationships would be helped by a plan (at least on an outline level) of the underground characterisation programme. We also note that many engineering matters are still to be confronted, not least the EBS design and its implementation, along with the treatment of high stresses, if Forsmark is selected. However, our views on the nature of the SR-Can analysis and the way in which site data have been utilised in it (our

Interface Simulation Distances

Directory of Open Access Journals (Sweden)

Pavol Černý

2012-10-01

Full Text Available The classical (boolean notion of refinement for behavioral interfaces of system components is the alternating refinement preorder. In this paper, we define a distance for interfaces, called interface simulation distance. It makes the alternating refinement preorder quantitative by, intuitively, tolerating errors (while counting them in the alternating simulation game. We show that the interface simulation distance satisfies the triangle inequality, that the distance between two interfaces does not increase under parallel composition with a third interface, and that the distance between two interfaces can be bounded from above and below by distances between abstractions of the two interfaces. We illustrate the framework, and the properties of the distances under composition of interfaces, with two case studies.

Research of Digital Interface Layout Design based on Eye-tracking

Directory of Open Access Journals (Sweden)

Shao Jiang

2015-01-01

Full Text Available The aim of this paper is to improve the low service efficiency and unsmooth human-computer interaction caused by currently irrational layouts of digital interfaces for complex systems. Also, three common layout structures for digital interfaces are to be presented and five layout types appropriate for multilevel digital interfaces are to be summarized. Based on the eye tracking technology, an assessment was conducted in advantages and disadvantages of different layout types through subjects’ search efficiency. Based on data and results, this study constructed a matching model which is appropriate for multilevel digital interface layout and verified the fact that the task element is a significant and important aspect of layout design. A scientific experimental model of research on digital interfaces for complex systems is provided. Both data and conclusions of the eye movement experiment provide a reference for layout designs of interfaces for complex systems with different task characteristics.

Studies of current-perpendicular-to-plane magnetoresistance (CPP-MR) and current-induced magnetization switching (CIMS)

Science.gov (United States)

Kurt, Huseyin

2005-08-01

We present two CPP-MR studies of spin-valves based upon ferromagnetic/nonmagnetic/ferromagnetic (F/N/F) trilayers. We measure the spin-diffusion lengths of N = Pd, Pt, and Au at 4.2K, and both the specific resistances (sample area A times resistance R) and spin-memory-loss of N/Cu interfaces. Pd, Pt and Au are of special device interest because they give perpendicular anisotropy when sandwiching very thin Co layers. Comparing our spin-memory-loss data at Pd/Cu and Pt/Cu interfaces with older data for Nb/Cu and W/Cu gives insight into the importance of spin-orbit coupling in producing such loss. We reproduce and extend prior studies by Eid of 'magnetic activity' at the interface of Co and N-metals (or combinations of N-metals), when the other side of the N-metal contacts a superconductor (S). Our data suggest that magnetic activity may require strong spin-flipping at the N/S interface. We present five studies of a new phenomenon, CIMS, in F1/N/F2 trilayers, with F1 a thick 'polarizing' layer and F2 a thin 'switching' layer. In all prior studies of CIMS, positive current caused the magnetization of F2 to switch from parallel (P) to anti-parallel (AP) to that of F1- 'normal' switching. By judicious addition of impurities to F-metals, we are able to controllably produce both 'normal' and 'inverse' switching- where positive current switches the magnetization of F2 from AP to P to that of F1. In the samples studied, whether the switching is normal or inverse is set by the 'net polarization' produced by F1 and is independent of the properties of F2. As scattering in the bulk of F1 and F2 is essential to producing our results, these results cannot be described by ballistic models, which allow scattering only at interfaces. Most CIMS experiments use Cu as the N-layer due to its low resistivity and long spin-diffusion length. We show that Ag and Au have low enough resistivities and long enough spin-diffusion lengths to be useful alternatives to Cu for some devices. While

Safety functions and safety function indicators - key elements in SKB'S methodology for assessing long-term safety of a KBS-3 repository

International Nuclear Information System (INIS)

Hedin, A.

2008-01-01

The application of so called safety function indicators in SKB safety assessment of a KBS-3 repository for spent nuclear fuel is presented. Isolation and retardation are the two main safety functions of the KBS-3 concept. In order to quantitatively evaluate safety on a sub-system level, these functions need to be differentiated, associated with quantitative measures and, where possible, with quantitative criteria relating to the fulfillment of the safety functions. A safety function is defined as a role through which a repository component contributes to safety. A safety function indicator is a measurable or calculable property of a repository component that allows quantitative evaluation of a safety function. A safety function indicator criterion is a quantitative limit such that if the criterion is fulfilled, the corresponding safety function is upheld. The safety functions and their associated indicators and criteria developed for the KBS-3 repository are primarily related to the isolating potential and to physical states of the canister and the clay buffer surrounding the canister. They are thus not directly related to release rates of radionuclides. The paper also describes how the concepts introduced i) aid in focussing the assessment on critical, safety related issues, ii) provide a framework for the accounting of safety throughout the different time frames of the assessment and iii) provide key information in the selection of scenarios for the safety assessment. (author)

Effect of interface roughness on the carrier transport in germanium MOSFETs investigated by Monte Carlo method

International Nuclear Information System (INIS)

Gang, Du; Xiao-Yan, Liu; Zhi-Liang, Xia; Jing-Feng, Yang; Ru-Qi, Han

2010-01-01

Interface roughness strongly influences the performance of germanium metal–organic–semiconductor field effect transistors (MOSFETs). In this paper, a 2D full-band Monte Carlo simulator is used to study the impact of interface roughness scattering on electron and hole transport properties in long- and short- channel Ge MOSFETs inversion layers. The carrier effective mobility in the channel of Ge MOSFETs and the in non-equilibrium transport properties are investigated. Results show that both electron and hole mobility are strongly influenced by interface roughness scattering. The output curves for 50 nm channel-length double gate n and p Ge MOSFET show that the drive currents of n- and p-Ge MOSFETs have significant improvement compared with that of Si n- and p-MOSFETs with smooth interface between channel and gate dielectric. The 82% and 96% drive current enhancement are obtained for the n- and p-MOSFETs with the completely smooth interface. However, the enhancement decreases sharply with the increase of interface roughness. With the very rough interface, the drive currents of Ge MOSFETs are even less than that of Si MOSFETs. Moreover, the significant velocity overshoot also has been found in Ge MOSFETs. (condensed matter: electronic structure, electrical, magnetic, and optical properties)

Spatial issues in user interface design from a graphic design perspective

Science.gov (United States)

Marcus, Aaron

1989-01-01

The user interface of a computer system is a visual display that provides information about the status of operations on data within the computer and control options to the user that enable adjustments to these operations. From the very beginning of computer technology the user interface was a spatial display, although its spatial features were not necessarily complex or explicitly recognized by the users. All text and nonverbal signs appeared in a virtual space generally thought of as a single flat plane of symbols. Current technology of high performance workstations permits any element of the display to appear as dynamic, multicolor, 3-D signs in a virtual 3-D space. The complexity of appearance and the user's interaction with the display provide significant challenges to the graphic designer of current and future user interfaces. In particular, spatial depiction provides many opportunities for effective communication of objects, structures, processes, navigation, selection, and manipulation. Issues are presented that are relevant to the graphic designer seeking to optimize the user interface's spatial attributes for effective visual communication.

Potential-specific structure at the hematite-electrolyte interface

Energy Technology Data Exchange (ETDEWEB)

McBriarty, Martin E.; Stubbs, Joanne; Eng, Peter; Rosso, Kevin M.

2018-02-21

The atomic-scale structure of interfaces between metal oxides and aqueous electrolytes controls their catalytic, geochemical, and corrosion behavior. Measurements that probe these interfaces in situ provide important details of ion and solvent arrangements, but atomically precise structural models do not exist for common oxide-electrolyte interfaces far from equilibrium. Using a novel cell, we measured the structure of the hematite (a-Fe₂O₃) (110$\\bar{2}$)-electrolyte interface under controlled electrochemical bias using synchrotron crystal truncation rod X ray scattering. At increasingly cathodic potentials, charge-compensating protonation of surface oxygen groups increases the coverage of specifically bound water while adjacent water layers displace outwardly and became disordered. Returning to open circuit potential leaves the surface in a persistent metastable protonation state. The flux of current and ions at applied potential is thus regulated by a unique interfacial electrolyte environment, suggesting that electrical double layer models should be adapted to the dynamically changing interfacial structure far from equilibrium.

Dark current of organic heterostructure devices with insulating spacer layers

Science.gov (United States)

Yin, Sun; Nie, Wanyi; Mohite, Aditya D.; Saxena, Avadh; Smith, Darryl L.; Ruden, P. Paul

2015-03-01

The dark current density at fixed voltage bias in donor/acceptor organic planar heterostructure devices can either increase or decrease when an insulating spacer layer is added between the donor and acceptor layers. The dominant current flow process in these systems involves the formation and subsequent recombination of an interfacial exciplex state. If the exciplex formation rate limits current flow, the insulating interface layer can increase dark current whereas, if the exciplex recombination rate limits current flow, the insulating interface layer decreases dark current. We present a device model to describe this behavior and illustrate it experimentally for various donor/acceptor systems, e.g. P3HT/LiF/C60.

Aspects of geochemical evolution of the SKB near field in the frame of SR-Site

International Nuclear Information System (INIS)

Sena, Clara; Salas, Joaquin; Arcos, David

2010-09-01

The concept for the final disposal of high level nuclear waste (HLNW) developed by the Swedish Nuclear Waste Management Company (SKB) entails a multi-barrier system that surrounds the HLNW, which is also known as the near-field. In the near-field, the buffer is initially subject to a high thermal gradient induced by the heat generated by the radioactive decay of the HLNW. During this period, the buffer is also subject to a hydrodynamic pressure induced by the surrounding water saturated rock massif which progressively leads to the saturation of the buffer. After saturation and cooling of the near-field, the interaction of groundwater with the bentonite buffer may result in an evolving distribution of some aqueous species in the bentonite porewater, as well as the redistribution of accessory minerals and the cation exchanger composition in the montmorillonite interlayer. The distribution of aqueous and solid species in the buffer can affect, directly or indirectly, some of the relevant safety function indicators defined by. In this context, the work developed by Arcos et al is revisited in the present work and, based on new data from SKB, additional models are developed for the SR-Site Safety Assessment. The work presented here represents an update of the model conducted within the SR-Can exercise and, therefore, similar simulation cases are developed. Three aspects must be considered regarding the geochemical evolution of the near field: (1) the effect of the thermal period; (2) the processes during the saturation of bentonite; and, (3) the interaction of the water-saturated bentonite with the local groundwater. In this numerical exercise, two types of bentonite are analysed: the MX-80 and the Deponit CA-N. The effect of the thermal period and the water saturation are analysed in a series of one-dimensional radial-symmetric simulations performed using TOUGHREACT which is a reactive transport code that accounts for variably saturated multi-phase flow under non

Aspects of geochemical evolution of the SKB near field in the frame of SR-Site

Energy Technology Data Exchange (ETDEWEB)

Sena, Clara; Salas, Joaquin; Arcos, David (Amphos 21, Barcelona (Spain))

2010-09-15

The concept for the final disposal of high level nuclear waste (HLNW) developed by the Swedish Nuclear Waste Management Company (SKB) entails a multi-barrier system that surrounds the HLNW, which is also known as the near-field. In the near-field, the buffer is initially subject to a high thermal gradient induced by the heat generated by the radioactive decay of the HLNW. During this period, the buffer is also subject to a hydrodynamic pressure induced by the surrounding water saturated rock massif which progressively leads to the saturation of the buffer. After saturation and cooling of the near-field, the interaction of groundwater with the bentonite buffer may result in an evolving distribution of some aqueous species in the bentonite porewater, as well as the redistribution of accessory minerals and the cation exchanger composition in the montmorillonite interlayer. The distribution of aqueous and solid species in the buffer can affect, directly or indirectly, some of the relevant safety function indicators defined by. In this context, the work developed by Arcos et al is revisited in the present work and, based on new data from SKB, additional models are developed for the SR-Site Safety Assessment. The work presented here represents an update of the model conducted within the SR-Can exercise and, therefore, similar simulation cases are developed. Three aspects must be considered regarding the geochemical evolution of the near field: (1) the effect of the thermal period; (2) the processes during the saturation of bentonite; and, (3) the interaction of the water-saturated bentonite with the local groundwater. In this numerical exercise, two types of bentonite are analysed: the MX-80 and the Deponit CA-N. The effect of the thermal period and the water saturation are analysed in a series of one-dimensional radial-symmetric simulations performed using TOUGHREACT which is a reactive transport code that accounts for variably saturated multi-phase flow under non

Usability of Three Electroencephalogram Headsets for Brain-Computer Interfaces: A Within Subject Comparison

NARCIS (Netherlands)

Gamboa, H.; Nijboer, Femke; van de Laar, B.L.A.; Plácido da Silva, H.; Gilleade, K.; Gerritsen, Steven; Nijholt, Antinus; Bermúdez i Badia, S.; Poel, Mannes; Fairclough, S.

Currently the field of brain–computer interfacing is increasingly focused on developing usable brain–computer interfaces (BCIs) to better ensure technology transfer and acceptance. Many studies have investigated the usability of BCI applications as a whole. Here we aim to investigate one specific

Interface Consistency

DEFF Research Database (Denmark)

Staunstrup, Jørgen

1998-01-01

This paper proposes that Interface Consistency is an important issue for the development of modular designs. Byproviding a precise specification of component interfaces it becomes possible to check that separately developedcomponents use a common interface in a coherent matter thus avoiding a very...... significant source of design errors. Awide range of interface specifications are possible, the simplest form is a syntactical check of parameter types.However, today it is possible to do more sophisticated forms involving semantic checks....

Implementation of graphical user interfaces in nuclear applications

International Nuclear Information System (INIS)

Barmsnes, K.A.; Johnsen, T.; Sundling, C.-V.

1997-01-01

During recent years a demand has formed for systems that support design and implementation of graphical user interfaces (GUIs) in the control rooms of nuclear power plants. Picasso-3 is a user interface management system supporting object oriented definition of GUIs in a distributed computing environment. The system is currently being used in a number of different application areas within the nuclear industry, such as retrofitting of display systems in simulators and control rooms, education and training applications, etc. Some examples are given of nuclear applications where the Picasso-3 system has been used

Test cases for interface tracking methods: methodology and current status

International Nuclear Information System (INIS)

Lebaigue, O.; Jamet, D.; Lemonnier, E.

2004-01-01

Full text of publication follows:In the past decade, a large number of new methods have been developed to deal with interfaces in the numerical simulation of two-phase flows. We have collected a set of 36 test cases, which can be seen as a tool to help engineers and researchers selecting the most appropriate method(s) for their specific fields of application. This set can be use: - To perform an initial evaluation of the capabilities of available methods with regard to the specificity of the final application and the most important features to be recovered from the simulation. - To measure the maximum mesh size to be used for a given physical problem in order to obtain an accurate enough solution. - To assess and quantify the performances of a selected method equipped with its set of physical models. The computation of a well-documented test case allows estimating the error due to the numerical technique by comparison with reference solutions. This process is compulsory to gain confidence and credibility on the prediction capabilities of a numerical method and its physical models. - To broaden the capabilities of a given numerical technique. The test cases may be used to identify the need for improvement of the overall numerical scheme or to determine the physical part of the model, which is responsible for the observed limitations. Each test case falls within one of the following categories: - Analytical solutions of well-known sets of equations corresponding to simple geometrical situations. - Reference numerical solutions of moderately complex problems, produced by accurate methods (e.g., boundary Fitted coordinate method) on refined meshes. - Separate effects analytical experiments. The presentation will suggest how to use the test cases for assessing the physical models and the numerical methods. The expected fallout of using test cases is indeed on the one hand to identify the merits of existing methods and on the other hand to orient further research towards

Concentration polarization: Electrodeposition and transport phenomena at overlimiting current

DEFF Research Database (Denmark)

Nielsen, Christoffer Peder

a numerical sharp-interface model describing the electrode growth. This model differs from the established phase-field models, in that it is applicable at overlimiting current and implements electrode reactions in a consistent way. Comparison of the sharp-interface model to the results of the stability...... methods. The initial study concerns a fundamental problem in the study of concentration polarization at overlimiting current, namely the emergence of an extended space-charge region near the ion-selective interface. Based on the so-called quasi-uniform charge density assumption (QCD), we develop...... this coupled chemical and transport effect using two simple models of the reaction kinetics. The principal investigations are performed using numerical simulations, but in addition we derive an analytical model for the transport in the system. The analytical model reveals an important link between the current...

Spin currents in a normal two-dimensional electron gas in contact with a spin-orbit interaction region

International Nuclear Information System (INIS)

Sukhanov, Aleksei A; Sablikov, Vladimir A; Tkach, Yurii Ya

2009-01-01

Spin effects in a normal two-dimensional (2D) electron gas in lateral contact with a 2D region with spin-orbit interaction are studied. The peculiarity of this system is the presence of spin-dependent scattering of electrons from the interface. This results in an equilibrium edge spin current and nontrivial spin responses to a particle current. We investigate the spatial distribution of the spin currents and spin density under non-equilibrium conditions caused by a ballistic electron current flowing normal or parallel to the interface. The parallel electron current is found to generate a spin density near the interface and to change the edge spin current. The perpendicular electron current changes the edge spin current proportionally to the electron current and produces a bulk spin current penetrating deep into the normal region. This spin current has two components, one of which is directed normal to the interface and polarized parallel to it, and the second is parallel to the interface and is polarized in the plane perpendicular to the contact line. Both spin currents have a high degree of polarization (∼40-60%).

Portraying User Interface History

DEFF Research Database (Denmark)

Jørgensen, Anker Helms

2008-01-01

history. Next the paper analyses a selected sample of papers on UI history at large. The analysis shows that the current state-of-art is featured by three aspects: Firstly internalism, in that the papers adress the tech­nologies in their own right with little con­text­ualization, secondly whiggism...... in that they largely address prevailing UI techno­logies, and thirdly history from above in that they focus on the great deeds of the visionaries. The paper then compares this state-of-art in UI history to the much more mature fields history of computing and history of technology. Based hereon, some speculations......The user interface is coming of age. Papers adressing UI history have appeared in fair amounts in the last 25 years. Most of them address particular aspects such as an in­novative interface paradigm or the contribution of a visionary or a research lab. Contrasting this, papers addres­sing UI...

Near interface traps in SiO{sub 2}/4H-SiC metal-oxide-semiconductor field effect transistors monitored by temperature dependent gate current transient measurements

Energy Technology Data Exchange (ETDEWEB)

Fiorenza, Patrick; La Magna, Antonino; Vivona, Marilena; Roccaforte, Fabrizio [Consiglio Nazionale delle Ricerche-Istituto per la Microelettronica e Microsistemi (CNR-IMM), Strada VIII 5, Zona Industriale 95121 Catania (Italy)

2016-07-04

This letter reports on the impact of gate oxide trapping states on the conduction mechanisms in SiO{sub 2}/4H-SiC metal-oxide-semiconductor field effect transistors (MOSFETs). The phenomena were studied by gate current transient measurements, performed on n-channel MOSFETs operated in “gate-controlled-diode” configuration. The measurements revealed an anomalous non-steady conduction under negative bias (V{sub G} > |20 V|) through the SiO{sub 2}/4H-SiC interface. The phenomenon was explained by the coexistence of a electron variable range hopping and a hole Fowler-Nordheim (FN) tunnelling. A semi-empirical modified FN model with a time-depended electric field is used to estimate the near interface traps in the gate oxide (N{sub trap} ∼ 2 × 10{sup 11} cm{sup −2}).

An Accessible User Interface for Geoscience and Programming

Science.gov (United States)

Sevre, E. O.; Lee, S.

2012-12-01

The goal of this research is to develop an interface that will simplify user interaction with software for scientists. The motivating factor of the research is to develop tools that assist scientists with limited motor skills with the efficient generation and use of software tools. Reliance on computers and programming is increasing in the world of geology, and it is increasingly important for geologists and geophysicists to have the computational resources to use advanced software and edit programs for their research. I have developed a prototype of a program to help geophysicists write programs using a simple interface that requires only simple single-mouse-clicks to input code. It is my goal to minimize the amount of typing necessary to create simple programs and scripts to increase accessibility for people with disabilities limiting fine motor skills. This interface can be adapted for various programming and scripting languages. Using this interface will simplify development of code for C/C++, Java, and GMT, and can be expanded to support any other text based programming language. The interface is designed around the concept of maximizing the amount of code that can be written using a minimum number of clicks and typing. The screen is split into two sections: a list of click-commands is on the left hand side, and a text area is on the right hand side. When the user clicks on a command on the left hand side the applicable code is automatically inserted at the insertion point in the text area. Currently in the C/C++ interface, there are commands for common code segments that are often used, such as for loops, comments, print statements, and structured code creation. The primary goal is to provide an interface that will work across many devices for developing code. A simple prototype has been developed for the iPad. Due to the limited number of devices that an iOS application can be used with, the code has been re-written in Java to run on a wider range of devices

Visual interface for space and terrestrial analysis

Science.gov (United States)

Dombrowski, Edmund G.; Williams, Jason R.; George, Arthur A.; Heckathorn, Harry M.; Snyder, William A.

1995-01-01

The management of large geophysical and celestial data bases is now, more than ever, the most critical path to timely data analysis. With today's large volume data sets from multiple satellite missions, analysts face the task of defining useful data bases from which data and metadata (information about data) can be extracted readily in a meaningful way. Visualization, following an object-oriented design, is a fundamental method of organizing and handling data. Humans, by nature, easily accept pictorial representations of data. Therefore graphically oriented user interfaces are appealing, as long as they remain simple to produce and use. The Visual Interface for Space and Terrestrial Analysis (VISTA) system, currently under development at the Naval Research Laboratory's Backgrounds Data Center (BDC), has been designed with these goals in mind. Its graphical user interface (GUI) allows the user to perform queries, visualization, and analysis of atmospheric and celestial backgrounds data.

Evaluation and modelling of SWIW tests performed within the SKB site characterisation programme

International Nuclear Information System (INIS)

Nordqvist, Rune

2008-08-01

In this report, a comprehensive overview of SWIW (Single Well Injection-Withdrawal) tests carried out within the SKB site investigations at Oskarshamn and Forsmark is presented. The purpose of this study is to make a general review and a comparison of performed SWIW tests within the site investigation programmes at the two sites. The study summarises experimental conditions for each test and discusses factors that may influence the experimental results and evaluation of the tests. Further, an extended model evaluation is carried out using a one- dimensional radial flow and transport model with matrix diffusion and matrix sorption. The intended outcome is an improved understanding of various mechanisms that may influence the SWIW test results and also to improve interpretation of the tests. Six SWIW test at each site have been carried out, generally resulting in high-quality and well documented experimental data with high tracer recovery. The tests have been performed in surface boreholes at repository depth, ranging approximately between 300 to 700 m borehole lengths. In all of the tests, a non-sorbing tracer (Uranine) and one or two sorbing tracers (cesium and rubidium) have been used simultaneously. A general result is that all of the tests demonstrate a very clear and relatively large retardation effect for the sorbing tracers. Basic initial modelling of the SWIW tests data, using a one-dimensional radial flow model with advection and dispersion, generally resulted in relatively good agreement between model and experimental data. However, a consistent feature of the initial modelling was a discrepancy between model and experimental data in the later parts of the recovery tracer breakthrough curve. It was concluded that this likely was caused by processes occurring in the tested rock formation and therefore an extended model evaluation (presented in this report) including matrix diffusion was carried out on all of the performed tests. Evaluated retardation

Evaluation and modelling of SWIW tests performed within the SKB site characterisation programme

Energy Technology Data Exchange (ETDEWEB)

Nordqvist, Rune (Geosigma AB, Uppsala (SE))

2008-08-15

In this report, a comprehensive overview of SWIW (Single Well Injection-Withdrawal) tests carried out within the SKB site investigations at Oskarshamn and Forsmark is presented. The purpose of this study is to make a general review and a comparison of performed SWIW tests within the site investigation programmes at the two sites. The study summarises experimental conditions for each test and discusses factors that may influence the experimental results and evaluation of the tests. Further, an extended model evaluation is carried out using a one- dimensional radial flow and transport model with matrix diffusion and matrix sorption. The intended outcome is an improved understanding of various mechanisms that may influence the SWIW test results and also to improve interpretation of the tests. Six SWIW test at each site have been carried out, generally resulting in high-quality and well documented experimental data with high tracer recovery. The tests have been performed in surface boreholes at repository depth, ranging approximately between 300 to 700 m borehole lengths. In all of the tests, a non-sorbing tracer (Uranine) and one or two sorbing tracers (cesium and rubidium) have been used simultaneously. A general result is that all of the tests demonstrate a very clear and relatively large retardation effect for the sorbing tracers. Basic initial modelling of the SWIW tests data, using a one-dimensional radial flow model with advection and dispersion, generally resulted in relatively good agreement between model and experimental data. However, a consistent feature of the initial modelling was a discrepancy between model and experimental data in the later parts of the recovery tracer breakthrough curve. It was concluded that this likely was caused by processes occurring in the tested rock formation and therefore an extended model evaluation (presented in this report) including matrix diffusion was carried out on all of the performed tests. Evaluated retardation

The APS intranet as a man-machine interface

International Nuclear Information System (INIS)

Ciarlette, D.; Gerig, R.; McDowell, W.

1997-01-01

The Advanced Photon Source at Argonne National Laboratory has implemented a number of methods for people to interact with the accelerator systems. The accelerator operators use Sun workstations running MEDM and WCL to interface interactively with the accelerator, however, many people need to view information rather than interact with the machine. One of the most common interfaces for viewing information at the Advanced Photon Source is the World Wide Web. Information such as operations logbook entries, machine status updates, and displays of archived and current data are easily available to APS personnel. This interface between people and the accelerator has proven to be quite useful. Because the Intranet is operating-system independent and inherently unidirectional, ensuring the prevention of unauthorized or accidental control of the accelerators is straightforward

The GEANT-CALOR interface

International Nuclear Information System (INIS)

Zeitnitz, C.; Gabriel, T.A.

1994-01-01

The simulation of large scale high energy physics experiments is based mainly on the GEANT package. In the current version 3.15 the simulation of hadronic interacting particles is based on GHEISHA or FLUKA. Both programs miss an accurate simulation of the interaction of low energy neutrons (E kin < 20 MeV) with the materials of the detector. The CALOR89 program package contains a low energetic neutron code. An interface between the CALOR program parts and the GEANT package has been developed

Open|SpeedShop Graphical User Interface Technology, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — We propose to create a new graphical user interface (GUI) for an existing parallel application performance and profiling tool, Open|SpeedShop. The current GUI has...

Review Statement and Evaluation of the Swedish Nuclear Fuel and Waste Management Co's RDandD Programme 2004. Programme for Research, Development and Demonstration of Methods for the Management and Disposal of Nuclear Waste, including Social Science Research

Energy Technology Data Exchange (ETDEWEB)

NONE

2005-12-15

integrated into this work to verify the models in time prior to a licence application. Furthermore, the authorities assume that more long-term biosphere issues are being taken into account in SKB's new plan of action. - In its biosphere research, SKB should take into account the possibility of using radionuclide concentrations and flows as complementary safety indicators. - SKB should more clearly explain how it will ensure that studied climate scenarios will shed light on the most important climate-related stresses on the barrier function. - It is justifiable for the research conducted by SKB and Sweden in the area of PandT to maintain its current level so that international developments can be followed and to maintain and develop scientific and technical expertise in areas of importance for nuclear safety. - A clarification of the account of deep boreholes prior to the ultimate choice of a method and prior to licensing under the Environmental Code is needed. A comparison should be made with the KBS-3 method which utilizes safety assessment methodology including simple calculations. - SKB needs to intensify the work on decommissioning issues and in order to present detailed plans and considerations in RDandD Programme 2007. - SKB should investigate the shortest time required for the start of a licensing process for the disposal of decommissioning waste. - In the next RDandD programme, SKB should provide a more detailed description of the programme for long-lived low and intermediate-level waste. - SKB should take into account the viewpoint that long-term interim storage of waste while waiting for the construction of a repository should, as far as possible, be avoided and take this into consideration in its planning. - It is positive that SKB has incorporated social science research into its programme, since the findings from the research should be useful for the stakeholders to apply the research findings in ongoing and future consultation processes for an

Review Statement and Evaluation of the Swedish Nuclear Fuel and Waste Management Co's RDandD Programme 2004. Programme for Research, Development and Demonstration of Methods for the Management and Disposal of Nuclear Waste, including Social Science Research

International Nuclear Information System (INIS)

2005-12-01

verify the models in time prior to a licence application. Furthermore, the authorities assume that more long-term biosphere issues are being taken into account in SKB's new plan of action. - In its biosphere research, SKB should take into account the possibility of using radionuclide concentrations and flows as complementary safety indicators. - SKB should more clearly explain how it will ensure that studied climate scenarios will shed light on the most important climate-related stresses on the barrier function. - It is justifiable for the research conducted by SKB and Sweden in the area of PandT to maintain its current level so that international developments can be followed and to maintain and develop scientific and technical expertise in areas of importance for nuclear safety. - A clarification of the account of deep boreholes prior to the ultimate choice of a method and prior to licensing under the Environmental Code is needed. A comparison should be made with the KBS-3 method which utilizes safety assessment methodology including simple calculations. - SKB needs to intensify the work on decommissioning issues and in order to present detailed plans and considerations in RDandD Programme 2007. - SKB should investigate the shortest time required for the start of a licensing process for the disposal of decommissioning waste. - In the next RDandD programme, SKB should provide a more detailed description of the programme for long-lived low and intermediate-level waste. - SKB should take into account the viewpoint that long-term interim storage of waste while waiting for the construction of a repository should, as far as possible, be avoided and take this into consideration in its planning. - It is positive that SKB has incorporated social science research into its programme, since the findings from the research should be useful for the stakeholders to apply the research findings in ongoing and future consultation processes for an encapsulation plant and repository

Review Statement and Evaluation of the Swedish Nuclear Fuel and Waste Management Co's RDandD Programme 2004. Programme for Research, Development and Demonstration of Methods for the Management and Disposal of Nuclear Waste, including Social Science Research

Energy Technology Data Exchange (ETDEWEB)

NONE

2005-12-15

verify the models in time prior to a licence application. Furthermore, the authorities assume that more long-term biosphere issues are being taken into account in SKB's new plan of action. - In its biosphere research, SKB should take into account the possibility of using radionuclide concentrations and flows as complementary safety indicators. - SKB should more clearly explain how it will ensure that studied climate scenarios will shed light on the most important climate-related stresses on the barrier function. - It is justifiable for the research conducted by SKB and Sweden in the area of PandT to maintain its current level so that international developments can be followed and to maintain and develop scientific and technical expertise in areas of importance for nuclear safety. - A clarification of the account of deep boreholes prior to the ultimate choice of a method and prior to licensing under the Environmental Code is needed. A comparison should be made with the KBS-3 method which utilizes safety assessment methodology including simple calculations. - SKB needs to intensify the work on decommissioning issues and in order to present detailed plans and considerations in RDandD Programme 2007. - SKB should investigate the shortest time required for the start of a licensing process for the disposal of decommissioning waste. - In the next RDandD programme, SKB should provide a more detailed description of the programme for long-lived low and intermediate-level waste. - SKB should take into account the viewpoint that long-term interim storage of waste while waiting for the construction of a repository should, as far as possible, be avoided and take this into consideration in its planning. - It is positive that SKB has incorporated social science research into its programme, since the findings from the research should be useful for the stakeholders to apply the research findings in ongoing and future consultation processes for an encapsulation plant and repository.

Using SNOMED CT to represent two interface terminologies.

Science.gov (United States)

Rosenbloom, S Trent; Brown, Steven H; Froehling, David; Bauer, Brent A; Wahner-Roedler, Dietlind L; Gregg, William M; Elkin, Peter L

2009-01-01

Interface terminologies are designed to support interactions between humans and structured medical information. In particular, many interface terminologies have been developed for structured computer based documentation systems. Experts and policy-makers have recommended that interface terminologies be mapped to reference terminologies. The goal of the current study was to evaluate how well the reference terminology SNOMED CT could map to and represent two interface terminologies, MEDCIN and the Categorical Health Information Structured Lexicon (CHISL). Automated mappings between SNOMED CT and 500 terms from each of the two interface terminologies were evaluated by human reviewers, who also searched SNOMED CT to identify better mappings when this was judged to be necessary. Reviewers judged whether they believed the interface terms to be clinically appropriate, whether the terms were covered by SNOMED CT concepts and whether the terms' implied semantic structure could be represented by SNOMED CT. Outcomes included concept coverage by SNOMED CT for study terms and their implied semantics. Agreement statistics and compositionality measures were calculated. The SNOMED CT terminology contained concepts to represent 92.4% of MEDCIN and 95.9% of CHISL terms. Semantic structures implied by study terms were less well covered, with some complex compositional expressions requiring semantics not present in SNOMED CT. Among sampled terms, those from MEDCIN were more complex than those from CHISL, containing an average 3.8 versus 1.8 atomic concepts respectively, pterms.

Affective Interface Adaptations in the Musickiosk Interactive Entertainment Application

Science.gov (United States)

Malatesta, L.; Raouzaiou, A.; Pearce, L.; Karpouzis, K.

The current work presents the affective interface adaptations in the Musickiosk application. Adaptive interaction poses several open questions since there is no unique way of mapping affective factors of user behaviour to the output of the system. Musickiosk uses a non-contact interface and implicit interaction through emotional affect rather than explicit interaction where a gesture, sound or other input directly maps to an output behaviour - as in traditional entertainment applications. PAD model is used for characterizing the different affective states and emotions.

A login shell interface for INFN-GRID

Energy Technology Data Exchange (ETDEWEB)

Pardi, S [INFN - Sezione di Napoli, Complesso di Monte S.Angelo - Via Cintia 80126 Napoli (Italy); Calloni, E; Rosa, R De; Garufi, F; Milano, L; Russo, G [Universita degli Studi di Napoli ' Federico M' , Dipartimento di Scienze Fisiche, Complesso di Monte S.Angelo - Via Cintia 80126 Napoli (Italy)], E-mail: silvio.pardi@na.infn.it

2008-12-15

The user interface is a crucial service to guarantee the Grid accessibility. The goal to achieve, is the implementation of an environment able to hide the grid complexity and offer a familiar interface to the final user. Currently many graphical interfaces have been proposed to simplify the grid access, but the GUI approach appears not very congenital to UNIX developers and users accustomed to work with command line interface. In 2004 the GridShell project proposed an extension of popular UNIX shells such as TCSH and BASH with features supporting Grid computing. Starting from the ideas included in GridShell, we propose IGSH (INFN-GRID SHELL) a new login shell for the INFN-GRID middleware, that interact with the Resource Broker services and integrates in a 'naturally way' the grid functionality with a familiar interface. The architecture of IGSH is very simple, it consist of a software layer on the top of the INFN-GRID middleware layer. When some operation is performed by the user, IGSH takes in charge to parse the syntax and translate it in the correspondents INFN-GRID commands according to some semantic rules specified in the next sections. The final user interacts with the underlying distributed infrastructure by using IGSH instead of his default login shell, with the sensation to work on a local machine.

A login shell interface for INFN-GRID

International Nuclear Information System (INIS)

Pardi, S; Calloni, E; Rosa, R De; Garufi, F; Milano, L; Russo, G

2008-01-01

The user interface is a crucial service to guarantee the Grid accessibility. The goal to achieve, is the implementation of an environment able to hide the grid complexity and offer a familiar interface to the final user. Currently many graphical interfaces have been proposed to simplify the grid access, but the GUI approach appears not very congenital to UNIX developers and users accustomed to work with command line interface. In 2004 the GridShell project proposed an extension of popular UNIX shells such as TCSH and BASH with features supporting Grid computing. Starting from the ideas included in GridShell, we propose IGSH (INFN-GRID SHELL) a new login shell for the INFN-GRID middleware, that interact with the Resource Broker services and integrates in a 'naturally way' the grid functionality with a familiar interface. The architecture of IGSH is very simple, it consist of a software layer on the top of the INFN-GRID middleware layer. When some operation is performed by the user, IGSH takes in charge to parse the syntax and translate it in the correspondents INFN-GRID commands according to some semantic rules specified in the next sections. The final user interacts with the underlying distributed infrastructure by using IGSH instead of his default login shell, with the sensation to work on a local machine.

User interface design principles for the SSM/PMAD automated power system

Science.gov (United States)

Jakstas, Laura M.; Myers, Chris J.

1991-01-01

Martin Marietta has developed a user interface for the space station module power management and distribution (SSM/PMAD) automated power system testbed which provides human access to the functionality of the power system, as well as exemplifying current techniques in user interface design. The testbed user interface was designed to enable an engineer to operate the system easily without having significant knowledge of computer systems, as well as provide an environment in which the engineer can monitor and interact with the SSM/PMAD system hardware. The design of the interface supports a global view of the most important data from the various hardware and software components, as well as enabling the user to obtain additional or more detailed data when needed. The components and representations of the SSM/PMAD testbed user interface are examined. An engineer's interactions with the system are also described.

Improvement of the electrical contact resistance at rough interfaces using two dimensional materials

Energy Technology Data Exchange (ETDEWEB)

Hu, Jianchen; Pan, Chengbin; Lanza, Mario, E-mail: mlanza@suda.edu.cn [Institute of Functional Nano & Soft Materials (FUNSOM), Collaborative Innovation Center of Suzhou Nanoscience and Technology, Soochow University, 199 Ren-Ai Road, Suzhou 215123 (China); Li, Heng [State Key Laboratory for Turbulence and Complex System, Department of Mechanics and Engineering Science, College of Engineering, Peking University, Beijing 100871 (China); CAPT, HEDPS and IFSA Collaborative Innovation Center of MoE, Peking University, Beijing 100871 (China); Shen, Panpan; Sun, Hui; Duan, Huiling [State Key Laboratory for Turbulence and Complex System, Department of Mechanics and Engineering Science, CAPT, College of Engineering, Peking University, Beijing 100871 (China)

2015-12-07

Reducing the electronic contact resistance at the interfaces of nanostructured materials is a major goal for many kinds of planar and three dimensional devices. In this work, we develop a method to enhance the electronic transport at rough interfaces by inserting a two dimensional flexible and conductive graphene sheet. We observe that an ultra-thin graphene layer with a thickness of 0.35 nm can remarkably reduce the roughness of a sample in a factor of 40%, avoiding the use of thick coatings, leading to a more homogeneous current flow, and extraordinarily increasing the total current compared to the graphene-free counterpart. Due to its simplicity and performance enhancement, this methodology can be of interest to many interface and device designers.

Three Dimensional Modelling of Canister for Spent Nuclear Fuel - some migration studies

Energy Technology Data Exchange (ETDEWEB)

Pereira, Antonio [AlbaNova Univ. Center, Stockholm (Sweden). Dept. of Physics

2006-08-15

Performance assessment transport models use extensively the concept of transport resistance in the calculation of breakthrough curves of radionuclide releases in the near field and geosphere. The aim of this work is to examine more closely the applicability of the transport resistance approach. Can the resistance approach be used in for the estimation of fluxes through a pinhole of a defected canister? Or for the estimation of fluxes as given by the resistance of a fracture that crosses a canister hole? And if so, what is the degree of conservatism (if any) introduced by the use of that concept? Two near-field 3D-models of the system consisting of canister, bentonite buffer and fracture have been developed. The goal is to examine the contribution to mass-transfer resistance of the interfaces between pinhole and bentonite buffer and between bentonite buffer and fracture respectively and to compare them with the resistance approach used by SKB in their compartment models of the near field. For this purpose we have developed two 3D models using the FEMLAB tool, to perform the set of calculations presented in this report. We estimate the above mentioned resistances separately for the interface between pinhole and bentonite buffer and for the interface between bentonite buffer and fracture respectively and we make a series of parameter variation studies. We conclude that the pinhole resistance used by SKB is a good approach to be used by compartment models even if some small discrepancy exists whenever the cross-section of the pinhole is larger than 10{sup -4} m{sup 2}. In respect to the fracture resistance parameterisation used in some SKB compartment models, the method is clearly conservative in many cases, with the exception for time points shorter than 200 years. This is due to the fact that the transient breakthrough curves cannot be described accurately by the parameterisation derived from the solution of the steady state equations used as the start point to

Three Dimensional Modelling of a KBS-3 Canister for Spent Nuclear Fuel - some migration studies

International Nuclear Information System (INIS)

Pereira, Antonio

2006-08-01

Performance assessment transport models use extensively the concept of transport resistance in the calculation of breakthrough curves of radionuclide releases in the near field and geosphere. The aim of this work is to examine more closely the applicability of the transport resistance approach. Can the resistance approach be used in for the estimation of fluxes through a pinhole of a defected canister? Or for the estimation of fluxes as given by the resistance of a fracture that crosses a canister hole? And if so, what is the degree of conservatism (if any) introduced by the use of that concept? Two near-field 3D-models of the system consisting of canister, bentonite buffer and fracture have been developed. The goal is to examine the contribution to mass-transfer resistance of the interfaces between pinhole and bentonite buffer and between bentonite buffer and fracture respectively and to compare them with the resistance approach used by SKB in their compartment models of the near field. For this purpose we have developed two 3D models using the FEMLAB tool, to perform the set of calculations presented in this report. We estimate the above mentioned resistances separately for the interface between pinhole and bentonite buffer and for the interface between bentonite buffer and fracture respectively and we make a series of parameter variation studies. We conclude that the pinhole resistance used by SKB is a good approach to be used by compartment models even if some small discrepancy exists whenever the cross-section of the pinhole is larger than 10 -4 m 2 . In respect to the fracture resistance parameterisation used in some SKB compartment models, the method is clearly conservative in many cases, with the exception for time points shorter than 200 years. This is due to the fact that the transient breakthrough curves cannot be described accurately by the parameterisation derived from the solution of the steady state equations used as the start point to deduce the

Energy level alignment and molecular conformation at rubrene/Ag interfaces: Impact of contact contaminations on the interfaces

Energy Technology Data Exchange (ETDEWEB)

Sinha, Sumona, E-mail: sumona.net.09@gmail.com [Saha Institute of Nuclear Physics, 1/AF, Bidhannagar, Kolkata 700064 (India); Wang, C.-H. [National Synchrotron Radiation Research Center, Hsinchu 30076, Taiwan (China); Mukherjee, M. [Saha Institute of Nuclear Physics, 1/AF, Bidhannagar, Kolkata 700064 (India)

2017-07-01

Highlights: • Impact of contact contaminations on the energy level alignment and molecular conformation at rubrene/Ag interfaces. • Adventitious contamination layer was acted as a spacer layer between Ag substrate surface and rubrene molecular layer. • Hole injection barrier height and interface dipole at rubrene/Ag interfaces depend on the cleanliness of Ag substrate. • Molecular conformation as well as orientation controlled by the cleanliness of Ag surface. • Resulted different surface morphology of rubrene thin films on unclean and clean Ag substrate. - Abstract: This paper addresses the impact of electrode contaminations on the interfacial energy level alignment, the molecular conformation, orientation and surface morphology deposited organic film at organic semiconductor/noble metal interfaces by varying of film thickness from sub-monolayer to multilayer, which currently draws significant attention with regard to its application in organic electronics. The UHV clean Ag and unclean Ag were employed as substrate whereas rubrene was used as an organic semiconducting material. The photoelectron spectroscopy (XPS and UPS) was engaged to investigate the evolution of interfacial energetics; polarization dependent near edge x-ray absorption fine structure spectroscopy (NEXAFS) was employed to understand the molecular conformation as well as orientation whereas atomic force microscopy (AFM) was used to investigate the surface morphologies of the films. The adventitious contamination layer was acted as a spacer layer between clean Ag substrate surface and rubrene molecular layer. As a consequence, hole injection barrier height, interface dipole as well as molecular-conformation, molecular-orientation and surface morphology of rubrene thin films were found to depend on the cleanliness of Ag substrate. The results have important inferences about the understanding of the impact of substrate contamination on the energy level alignment, the molecular conformation

Effect of interface structure regulation caused by variation of imidization rate on conduction current characteristics of PI/nano-Al2O3 three-layer composite films

Science.gov (United States)

Ma, Xinyu; Liu, Lizhu; Zhang, Xiaorui; He, Hongju

2018-06-01

A series of sandwich structure PI films were prepared by different imidization process, with pure PI film as the interlayer and PI/Al2O3 composite films as outer layers. The imidization rate of the film with different cured processes was calculated by characterizing by infrared spectrum (FT-IR), and the morphology of interlayer interface with different imidization rates by scanning electron microscope (SEM). When the imidization conditions of the first and second films were 260 °C/120 min, the composite films displayed better interface structure and higher imidization rate (ID) than others. Moreover, results also showed that the conduction current of three-layer composite film steadily improved with increased ID and temperature, and was higher than that of the pure film. At the temperature of 30 °C, the electrical aging threshold at different ID was obtained. When the ID reached the maximum value of 78.9%, the electrical aging threshold reached the maximum 41.69 kV/mm.

Interface models

DEFF Research Database (Denmark)

Ravn, Anders P.; Staunstrup, Jørgen

1994-01-01

This paper proposes a model for specifying interfaces between concurrently executing modules of a computing system. The model does not prescribe a particular type of communication protocol and is aimed at describing interfaces between both software and hardware modules or a combination of the two....... The model describes both functional and timing properties of an interface...

Improved adaptive input voltage control of a solar array interfacing current mode controlled boost power stage

International Nuclear Information System (INIS)

Sitbon, Moshe; Schacham, Shmuel; Suntio, Teuvo; Kuperman, Alon

2015-01-01

Highlights: • Photovoltaic generator dynamic resistance online estimation method is proposed. • Control method allowing to achieve nominal performance at all time is presented. • The method is suitable for any type of photovoltaic system. - Abstract: Nonlinear characteristics of photovoltaic generators were recently shown to significantly influence the dynamics of interfacing power stages. Moreover, since the dynamic resistance of photovoltaic generators is both operating point and environmental variables dependent, the combined dynamics exhibits these dependencies as well, burdening control challenge. Typically, linear time invariant input voltage loop controllers (e.g. Proportional-Integrative-Derivative) are utilized in photovoltaic applications, designed according to nominal operating conditions. Nevertheless, since actual dynamics is seldom nominal, closed loop performance of such systems varies as well. In this paper, adaptive control method is proposed, allowing to estimate photovoltaic generator resistance online and utilize it to modify the controller parameters such that closed loop performance remains nominal throughout the whole operation range. Unlike previously proposed method, utilizing double-grid-frequency component for estimation purposes and suffering from various drawbacks such as operation point dependence and applicability to single-phase grid connected systems only, the proposed method is based on harmonic current injection and is independent on operating point and system topology

Emulating conventional operator interfaces on window-based workstations

International Nuclear Information System (INIS)

Carr, G.P.

1990-01-01

This paper explores an approach to support the LAMPF and PSR control systems on VAX/VMS workstations using DECwindows and VI Corporation Data Views as the operator interface. The PSR control system was recently turned over to MP division and the two control-system staffs were merged into one group. One of the goals of this new group is to develop a common workstation-based operator console and interface which can be used in a single control room controlling both the linac and proton storage ring. The new console operator interface will need a high-level graphics toolkit for its implementation. During the conversion to the new consoles it will also probably be necessary to write a package to emulate the current operator interfaces at the software level. This paper describes a project to evaluate the appropriateness of VI Corporation's Data Views graphics package for use in the LAMPF control-system environment by using it to write an emulation of the LAMPF touch-panel interface to a large LAMPF control-system application program. A secondary objective of this project was to explore any productivity increases that might be realized by using an object-oriented graphics package and graphics editor. (orig.)

Electrical doping: the impact on interfaces of π-conjugated molecular films

International Nuclear Information System (INIS)

Gao Weiying; Kahn, Antoine

2003-01-01

Organic-metal and organic-organic interfaces play crucial roles in charge injection in, and transport through, organic thin film devices. Their electronic structure, chemical properties and electrical behaviour must be fully characterized and understood if engineering and control of organic devices are to reach the levels attained for inorganic semiconductor devices. Recent fundamental, as well as device, work has demonstrated that electrical doping provides a very interesting way to improve carrier injection into molecular films and, eventually, control molecular level alignment at their interfaces. This brief review emphasizes the current understanding of the effects of doping on organic interfaces

Applications for Packetized Memory Interfaces

OpenAIRE

Watson, Myles Glen

2015-01-01

The performance of the memory subsystem has a large impact on the performance of modern computer systems. Many important applications are memory bound and others are expected to become memory bound in the future. The importance of memory performance makes it imperative to understand and optimize the interactions between applications and the system architecture. Prototyping and exploring various configurations of memory systems can give important insights, but current memory interfaces are lim...

Shape-changing interfaces:

DEFF Research Database (Denmark)

Rasmussen, Majken Kirkegård; Pedersen, Esben Warming; Petersen, Marianne Graves

2015-01-01

Shape change is increasingly used in physical user interfaces, both as input and output. Yet, the progress made and the key research questions for shape-changing interfaces are rarely analyzed systematically. We review a sample of existing work on shape-changing interfaces to address these shortc......Shape change is increasingly used in physical user interfaces, both as input and output. Yet, the progress made and the key research questions for shape-changing interfaces are rarely analyzed systematically. We review a sample of existing work on shape-changing interfaces to address...... these shortcomings. We identify eight types of shape that are transformed in various ways to serve both functional and hedonic design purposes. Interaction with shape-changing interfaces is simple and rarely merges input and output. Three questions are discussed based on the review: (a) which design purposes may...

Effects of silicon:carbon P+ layer interfaces on solar cells

International Nuclear Information System (INIS)

Jeffrey, F.R.; Vernstrom, G.D.; Weber, M.F.; Gilbert, J.R.

1987-01-01

Results are presented showing the effects on amorphous silicon (a-Si) photovoltaic performance of the interfaces associated with a silicon carbide (a-Si:C) p+ layer. Carbon grading into the intrinsic layer from the p+ layer increases open circuit voltage (Voc) from 0.7V to 0.88V. This effect is very similar to the boron profile effect reported earlier and supports the contention that Voc is being limited by an electron current at the p-i interface. The interface between the p+ a-Si:C layer and the transparent conductive oxide (TCO) is shown to be a potential source of high series resistance, with an abrupt interface showing the most serious problem. The effect is explained by electron injection from the TCO into the p+ layer being inhibited as a result of band mismatch

Autonomous Control of Current and Voltage Controlled DG Interface Inverters for Reactive Power Sharing and Harmonics Compensation in Islanded Microgrids

DEFF Research Database (Denmark)

Mousazadeh, Seyyed Yousef; Jalilain, Alireza; Savaghebi, Mehdi

2018-01-01

In microgrids, Voltage Source Inverters (VSIs) interfacing Distributed Generation (DG) units can be operated in Voltage or Current Controlled Modes (VCM/CCM). In this paper, a coordinated control of CCM and VCM units for reactive power sharing and voltage harmonics compensation is proposed....... This decentralized control scheme is based on the local measurement of signals. In this way, the need for communication links is removed which results in a simpler and more reliable structure compared to the communication based control structures. To be more exact, the VCM units contribute to harmonics compensation....... Experimental and simulation studies show that the harmonics compensation is achieved by using only local measurements in presence of virtual admittance/impedance schemes of CCM/VCM units. Furthermore, it is demonstrated that the reactive power sharing among the CCM and VCM units is obtained based...

PointCom: semi-autonomous UGV control with intuitive interface

Science.gov (United States)

Rohde, Mitchell M.; Perlin, Victor E.; Iagnemma, Karl D.; Lupa, Robert M.; Rohde, Steven M.; Overholt, James; Fiorani, Graham

2008-04-01

Unmanned ground vehicles (UGVs) will play an important role in the nation's next-generation ground force. Advances in sensing, control, and computing have enabled a new generation of technologies that bridge the gap between manual UGV teleoperation and full autonomy. In this paper, we present current research on a unique command and control system for UGVs named PointCom (Point-and-Go Command). PointCom is a semi-autonomous command system for one or multiple UGVs. The system, when complete, will be easy to operate and will enable significant reduction in operator workload by utilizing an intuitive image-based control framework for UGV navigation and allowing a single operator to command multiple UGVs. The project leverages new image processing algorithms for monocular visual servoing and odometry to yield a unique, high-performance fused navigation system. Human Computer Interface (HCI) techniques from the entertainment software industry are being used to develop video-game style interfaces that require little training and build upon the navigation capabilities. By combining an advanced navigation system with an intuitive interface, a semi-autonomous control and navigation system is being created that is robust, user friendly, and less burdensome than many current generation systems. mand).

Interfacing An Intelligent Decision-Maker To A Real-Time Control System

Science.gov (United States)

Evers, D. C.; Smith, D. M.; Staros, C. J.

1984-06-01

This paper discusses some of the practical aspects of implementing expert systems in a real-time environment. There is a conflict between the needs of a process control system and the computational load imposed by intelligent decision-making software. The computation required to manage a real-time control problem is primarily concerned with routine calculations which must be executed in real time. On most current hardware, non-trivial AI software should not be forced to operate under real-time constraints. In order for the system to work efficiently, the two processes must be separated by a well-defined interface. Although the precise nature of the task separation will vary with the application, the definition of the interface will need to follow certain fundamental principles in order to provide functional separation. This interface was successfully implemented in the expert scheduling software currently running the automated chemical processing facility at Lockheed-Georgia. Potential applications of this concept in the areas of airborne avionics and robotics will be discussed.

Particle-bearing currents in uniform density and two-layer fluids

Science.gov (United States)

Sutherland, Bruce R.; Gingras, Murray K.; Knudson, Calla; Steverango, Luke; Surma, Christopher

2018-02-01

Lock-release gravity current experiments are performed to examine the evolution of a particle bearing flow that propagates either in a uniform-density fluid or in a two-layer fluid. In all cases, the current is composed of fresh water plus micrometer-scale particles, the ambient fluid is saline, and the current advances initially either over the surface as a hypopycnal current or at the interface of the two-layer fluid as a mesopycnal current. In most cases the tank is tilted so that the ambient fluid becomes deeper with distance from the lock. For hypopycnal currents advancing in a uniform density fluid, the current typically slows as particles rain out of the current. While the loss of particles alone from the current should increase the current's buoyancy and speed, in practice the current's speed decreases because the particles carry with them interstitial fluid from the current. Meanwhile, rather than settling on the sloping bottom of the tank, the particles form a hyperpycnal (turbidity) current that advances until enough particles rain out that the relatively less dense interstitial fluid returns to the surface, carrying some particles back upward. When a hypopycnal current runs over the surface of a two-layer fluid, the particles that rain out temporarily halt their descent as they reach the interface, eventually passing through it and again forming a hyperpycnal current. Dramatically, a mesopycnal current in a two-layer fluid first advances along the interface and then reverses direction as particles rain out below and fresh interstitial fluid rises above.

Experiences in Interagency and International Interfaces for Mission Support

Science.gov (United States)

Dell, G. T.; Mitchell, W. J.; Thompson, T. W.; Cappellari, J. O., Jr.; Flores-Amaya, F.

1996-01-01

The Flight Dynamics Division (FDD) of the National Aeronautics and Space Administration (NASA) Goddard Space Flight Center (GFSC) provides extensive support and products for Space Shuttle missions, expendable launch vehicle launches, and routine on-orbit operations for a variety of spacecraft. A major challenge in providing support for these missions is defining and generating the products required for mission support and developing the method by which these products are exchanged between supporting agencies. As interagency and international cooperation has increased in the space community, the FDD customer base has grown and with it the number and variety of external interfaces and product definitions. Currently, the FDD has working interfaces with the NASA Space and Ground Networks, the Johnson Space Center, the White Sands Complex, the Jet propulsion Laboratory (including the Deep Space Network), the United States Air Force, the Centre National d'Etudes Spatiales, the German Spaceflight Operations Center, the European Space Agency, and the National Space Development Agency of Japan. With the increasing spectrum of possible data product definitions and delivery methods, the FDD is using its extensive interagency experience to improve its support of established customers and to provide leadership in adapting/developing new interfaces. This paper describes the evolution of the interfaces between the FDD and its customers, discusses many of the joint activities ith these customers, and summarizes key lessons learned that can be applied to current and future support.

Mechanical properties along interfaces of bonded structures in fusion reactors

International Nuclear Information System (INIS)

Hassan, M.H.; Kulcinski, G.L.

1993-01-01

Proper assessment of the mechanical properties along interfaces of bonded structures currently used in many fusion reactor designs is essential to compare the different fabrication techniques. A Mechanical Properties Microprobe (MPM) was used to measure hardness and Young's modules along the interfaces of Be/Cu bonded structure. The MPM was able to distinguish different fabrication techniques by a direct measurement of the hardness, Young's modules, and H/E 2 which reflects the ability of deformation of the interfacial region

Modelling Safe Interface Interactions in Web Applications

Science.gov (United States)

Brambilla, Marco; Cabot, Jordi; Grossniklaus, Michael

Current Web applications embed sophisticated user interfaces and business logic. The original interaction paradigm of the Web based on static content pages that are browsed by hyperlinks is, therefore, not valid anymore. In this paper, we advocate a paradigm shift for browsers and Web applications, that improves the management of user interaction and browsing history. Pages are replaced by States as basic navigation nodes, and Back/Forward navigation along the browsing history is replaced by a full-fledged interactive application paradigm, supporting transactions at the interface level and featuring Undo/Redo capabilities. This new paradigm offers a safer and more precise interaction model, protecting the user from unexpected behaviours of the applications and the browser.

Using SNOMED CT to Represent Two Interface Terminologies

Science.gov (United States)

Rosenbloom, S. Trent; Brown, Steven H.; Froehling, David; Bauer, Brent A.; Wahner-Roedler, Dietlind L.; Gregg, William M.; Elkin, Peter L.

2009-01-01

Objective Interface terminologies are designed to support interactions between humans and structured medical information. In particular, many interface terminologies have been developed for structured computer based documentation systems. Experts and policy-makers have recommended that interface terminologies be mapped to reference terminologies. The goal of the current study was to evaluate how well the reference terminology SNOMED CT could map to and represent two interface terminologies, MEDCIN and the Categorical Health Information Structured Lexicon (CHISL). Design Automated mappings between SNOMED CT and 500 terms from each of the two interface terminologies were evaluated by human reviewers, who also searched SNOMED CT to identify better mappings when this was judged to be necessary. Reviewers judged whether they believed the interface terms to be clinically appropriate, whether the terms were covered by SNOMED CT concepts and whether the terms' implied semantic structure could be represented by SNOMED CT. Measurements Outcomes included concept coverage by SNOMED CT for study terms and their implied semantics. Agreement statistics and compositionality measures were calculated. Results The SNOMED CT terminology contained concepts to represent 92.4% of MEDCIN and 95.9% of CHISL terms. Semantic structures implied by study terms were less well covered, with some complex compositional expressions requiring semantics not present in SNOMED CT. Among sampled terms, those from MEDCIN were more complex than those from CHISL, containing an average 3.8 versus 1.8 atomic concepts respectively, pterms. PMID:18952944

Adhesion and failure analysis of metal-polymer interface in flexible printed circuits boards

Science.gov (United States)

Park, Sanghee; Kim, Ye Chan; Choi, Kisuk; Chae, Heeyop; Suhr, Jonghwan; Nam, Jae-Do

2017-12-01

As device miniaturization in microelectronics is currently requested in the development of high performance device, which usually include highly-integrated metal-polyimide multilayer structures. A redistribution layer (RDL) process is currently emerging as one of the most advance fabrication techniques for on-chip interconnect and packaging. One of the major issues in this process is the poor adhesion of the metal-polyimide interfaces particularly in flexible circuit boards due to the flexibility and bendability of devices. In this study, low pressure O2 plasma treatment was investigated to improve the adhesion of metal-polyimide interfaces, using inductively coupled plasma (ICP) treatment. We identified that the adhesion of metal-polyimide interfaces was greatly improved by the surface roughness control providing 46.1 MPa of shear force in the ball shear test after O2 plasma treatment, compared 14.2 MPa without O2 plasma treatment. It was seemingly due to the fact that the adhesion in metal-polyimide interfaces was improved by a chemical conversion of C=O to C-O bonds and by a ring opening reaction of imide groups, which was confirmed with FT-IR analysis. In the finite element numerical analysis of metal-polyimide interfaces, the O2 plasma treated interface showed that the in-plane stress distribution and the vertical directional deformation agreed well with real failure modes in flexible circuits manufacturing.

Performance characteristic of saturable three-phase interface transformers-investigations using a model simulation

Energy Technology Data Exchange (ETDEWEB)

Gierse, G; Pestka, J

1981-11-01

For electric locomotive drives equipped with converter fed squirrel cage induction motors the influence of different three-phase interface transformers on the smoothing of the motor currents is shown. In combination with a modified pulse-width-controlled thyristor firing system the size of the interface transformers can be greatly reduced without the distortion currents being greater than in the case of reactors in the motor supply lines. Finally, it is shown how the additional magnetic coupling of two driving systems can influence the behaviour of the two motors.

Current implementation and future plans on new code architecture, programming language and user interface

Energy Technology Data Exchange (ETDEWEB)

Brun, B. [Commissariat a l`Energie Atomique, Grenoble (France)

1997-07-01

Computer technology has improved tremendously during the last years with larger media capacity, memory and more computational power. Visual computing with high-performance graphic interface and desktop computational power have changed the way engineers accomplish everyday tasks, development and safety studies analysis. The emergence of parallel computing will permit simulation over a larger domain. In addition, new development methods, languages and tools have appeared in the last several years.

Current implementation and future plans on new code architecture, programming language and user interface

International Nuclear Information System (INIS)

Brun, B.

1997-01-01

Computer technology has improved tremendously during the last years with larger media capacity, memory and more computational power. Visual computing with high-performance graphic interface and desktop computational power have changed the way engineers accomplish everyday tasks, development and safety studies analysis. The emergence of parallel computing will permit simulation over a larger domain. In addition, new development methods, languages and tools have appeared in the last several years

SCOWLP: a web-based database for detailed characterization and visualization of protein interfaces

Directory of Open Access Journals (Sweden)

Schroeder Michael

2006-03-01

Full Text Available Abstract Background Currently there is a strong need for methods that help to obtain an accurate description of protein interfaces in order to be able to understand the principles that govern molecular recognition and protein function. Many of the recent efforts to computationally identify and characterize protein networks extract protein interaction information at atomic resolution from the PDB. However, they pay none or little attention to small protein ligands and solvent. They are key components and mediators of protein interactions and fundamental for a complete description of protein interfaces. Interactome profiling requires the development of computational tools to extract and analyze protein-protein, protein-ligand and detailed solvent interaction information from the PDB in an automatic and comparative fashion. Adding this information to the existing one on protein-protein interactions will allow us to better understand protein interaction networks and protein function. Description SCOWLP (Structural Characterization Of Water, Ligands and Proteins is a user-friendly and publicly accessible web-based relational database for detailed characterization and visualization of the PDB protein interfaces. The SCOWLP database includes proteins, peptidic-ligands and interface water molecules as descriptors of protein interfaces. It contains currently 74,907 protein interfaces and 2,093,976 residue-residue interactions formed by 60,664 structural units (protein domains and peptidic-ligands and their interacting solvent. The SCOWLP web-server allows detailed structural analysis and comparisons of protein interfaces at atomic level by text query of PDB codes and/or by navigating a SCOP-based tree. It includes a visualization tool to interactively display the interfaces and label interacting residues and interface solvent by atomic physicochemical properties. SCOWLP is automatically updated with every SCOP release. Conclusion SCOWLP enriches

Selectivity and Longevity of Peripheral-Nerve and Machine Interfaces: A Review

Directory of Open Access Journals (Sweden)

Usman Ghafoor

2017-10-01

Full Text Available For those individuals with upper-extremity amputation, a daily normal living activity is no longer possible or it requires additional effort and time. With the aim of restoring their sensory and motor functions, theoretical and technological investigations have been carried out in the field of neuroprosthetic systems. For transmission of sensory feedback, several interfacing modalities including indirect (non-invasive, direct-to-peripheral-nerve (invasive, and cortical stimulation have been applied. Peripheral nerve interfaces demonstrate an edge over the cortical interfaces due to the sensitivity in attaining cortical brain signals. The peripheral nerve interfaces are highly dependent on interface designs and are required to be biocompatible with the nerves to achieve prolonged stability and longevity. Another criterion is the selection of nerves that allows minimal invasiveness and damages as well as high selectivity for a large number of nerve fascicles. In this paper, we review the nerve-machine interface modalities noted above with more focus on peripheral nerve interfaces, which are responsible for provision of sensory feedback. The invasive interfaces for recording and stimulation of electro-neurographic signals include intra-fascicular, regenerative-type interfaces that provide multiple contact channels to a group of axons inside the nerve and the extra-neural-cuff-type interfaces that enable interaction with many axons around the periphery of the nerve. Section Current Prosthetic Technology summarizes the advancements made to date in the field of neuroprosthetics toward the achievement of a bidirectional nerve-machine interface with more focus on sensory feedback. In the Discussion section, the authors propose a hybrid interface technique for achieving better selectivity and long-term stability using the available nerve interfacing techniques.

Selectivity and Longevity of Peripheral-Nerve and Machine Interfaces: A Review

Science.gov (United States)

Ghafoor, Usman; Kim, Sohee; Hong, Keum-Shik

2017-01-01

For those individuals with upper-extremity amputation, a daily normal living activity is no longer possible or it requires additional effort and time. With the aim of restoring their sensory and motor functions, theoretical and technological investigations have been carried out in the field of neuroprosthetic systems. For transmission of sensory feedback, several interfacing modalities including indirect (non-invasive), direct-to-peripheral-nerve (invasive), and cortical stimulation have been applied. Peripheral nerve interfaces demonstrate an edge over the cortical interfaces due to the sensitivity in attaining cortical brain signals. The peripheral nerve interfaces are highly dependent on interface designs and are required to be biocompatible with the nerves to achieve prolonged stability and longevity. Another criterion is the selection of nerves that allows minimal invasiveness and damages as well as high selectivity for a large number of nerve fascicles. In this paper, we review the nerve-machine interface modalities noted above with more focus on peripheral nerve interfaces, which are responsible for provision of sensory feedback. The invasive interfaces for recording and stimulation of electro-neurographic signals include intra-fascicular, regenerative-type interfaces that provide multiple contact channels to a group of axons inside the nerve and the extra-neural-cuff-type interfaces that enable interaction with many axons around the periphery of the nerve. Section Current Prosthetic Technology summarizes the advancements made to date in the field of neuroprosthetics toward the achievement of a bidirectional nerve-machine interface with more focus on sensory feedback. In the Discussion section, the authors propose a hybrid interface technique for achieving better selectivity and long-term stability using the available nerve interfacing techniques. PMID:29163122

Local Electronic And Dielectric Properties at Nanosized Interfaces

Energy Technology Data Exchange (ETDEWEB)

Bonnell, Dawn A. [Univ. of Pennsylvania, Philadelphia, PA (United States)

2015-02-23

Final Report to the Department of Energy for period 6/1/2000 to 11/30/2014 for Grant # DE-FG02-00ER45813-A000 to the University of Pennsylvania Local Electronic And Dielectric Properties at Nanosized Interfaces PI: Dawn Bonnell The behavior of grain boundaries and interfaces has been a focus of fundamental research for decades because variations of structure and composition at interfaces dictate mechanical, electrical, optical and dielectric properties in solids. Similarly, the consequence of atomic and electronic structures of surfaces to chemical and physical interactions are critical due to their implications to catalysis and device fabrication. Increasing fundamental understanding of surfaces and interfaces has materially advanced technologies that directly bear on energy considerations. Currently, exciting developments in materials processing are enabling creative new electrical, optical and chemical device configurations. Controlled synthesis of nanoparticles, semiconducting nanowires and nanorods, optical quantum dots, etc. along with a range of strategies for assembling and patterning nanostructures portend the viability of new devices that have the potential to significantly impact the energy landscape. As devices become smaller the impact of interfaces and surfaces grows geometrically. As with other nanoscale phenomena, small interfaces do not exhibit the same properties as do large interfaces. The size dependence of interface properties had not been explored and understanding at the most fundamental level is necessary to the advancement of nanostructured devices. An equally important factor in the behavior of interfaces in devices is the ability to examine the interfaces under realistic conditions. For example, interfaces and boundaries dictate the behavior of oxide fuel cells which operate at extremely high temperatures in dynamic high pressure chemical environments. These conditions preclude the characterization of local properties during fuel cell

User Interface Design in Medical Distributed Web Applications.

Science.gov (United States)

Serban, Alexandru; Crisan-Vida, Mihaela; Mada, Leonard; Stoicu-Tivadar, Lacramioara

2016-01-01

User interfaces are important to facilitate easy learning and operating with an IT application especially in the medical world. An easy to use interface has to be simple and to customize the user needs and mode of operation. The technology in the background is an important tool to accomplish this. The present work aims to creating a web interface using specific technology (HTML table design combined with CSS3) to provide an optimized responsive interface for a complex web application. In the first phase, the current icMED web medical application layout is analyzed, and its structure is designed using specific tools, on source files. In the second phase, a new graphic adaptable interface to different mobile terminals is proposed, (using HTML table design (TD) and CSS3 method) that uses no source files, just lines of code for layout design, improving the interaction in terms of speed and simplicity. For a complex medical software application a new prototype layout was designed and developed using HTML tables. The method uses a CSS code with only CSS classes applied to one or multiple HTML table elements, instead of CSS styles that can be applied to just one DIV tag at once. The technique has the advantage of a simplified CSS code, and a better adaptability to different media resolutions compared to DIV-CSS style method. The presented work is a proof that adaptive web interfaces can be developed just using and combining different types of design methods and technologies, using HTML table design, resulting in a simpler to learn and use interface, suitable for healthcare services.

Water at Interfaces.

Science.gov (United States)

Björneholm, Olle; Hansen, Martin H; Hodgson, Andrew; Liu, Li-Min; Limmer, David T; Michaelides, Angelos; Pedevilla, Philipp; Rossmeisl, Jan; Shen, Huaze; Tocci, Gabriele; Tyrode, Eric; Walz, Marie-Madeleine; Werner, Josephina; Bluhm, Hendrik

2016-07-13

The interfaces of neat water and aqueous solutions play a prominent role in many technological processes and in the environment. Examples of aqueous interfaces are ultrathin water films that cover most hydrophilic surfaces under ambient relative humidities, the liquid/solid interface which drives many electrochemical reactions, and the liquid/vapor interface, which governs the uptake and release of trace gases by the oceans and cloud droplets. In this article we review some of the recent experimental and theoretical advances in our knowledge of the properties of aqueous interfaces and discuss open questions and gaps in our understanding.

Effect of material selection and background impurity on interface property and resulted CIP-GMR performance

International Nuclear Information System (INIS)

Peng Xilin; Morrone, Augusto; Nikolaev, Konstantin; Kief, Mark; Ostrowski, Mark

2009-01-01

In this paper, we investigated the effect of background base pressure, wafer-transferring time between process modules, and stack layer material selection on the current-in-plane giant magneto-resistive (CIP-GMR) interface properties and the resulted CIP-GMR performance. Experimental results showed that seed layer/AFM interface, AFM/pinned layer (PL) interface, pinned layer/Ru interface, and reference layer (RL)/Cu spacer interface are among the most critical ones for a CIP-GMR device. By reducing the background impurity level (water moisture and oxygen), optimizing the wafer process flow sequence, and careful stack-layer material selection, such critical interfaces in a CIP-GMR device can be preserved. Consequently, a much robust GMR performance control can be achieved.

Ballistic electron emissions microscopy (BEEM) of ferromagnet-semiconductor interfaces; Ballistische Elektronen Emissions Mikroskopie (BEEM) an Ferromagnet-Halbleitergrenzflaechen

Energy Technology Data Exchange (ETDEWEB)

Obernhuber, S.

2007-04-15

For current research on spin-transistors it is important to know the characteristics of ferromagnet semiconductor interfaces. The ballistic electron emission microscopy (BEEM) is a method to investigate such a buried interface with nanometer resolution. In this work several ferromagnet/GaAs(110) interfaces have been analysed concerning their homogeneity and mean local Schottky-barrier heights (SBH) have been determined. In Addition, the resulting integral SBH was calculated from the distribution of the local SBHs and compared with the SBH determined from voltage/current characteristics. The areas with a low SBH dominate the current conduction across the interface. Additional BEEM measurements on (AlGaAs/GaAs) heterostructures have been performed. This heterostructures consist of 50 nm AlGaAs/GaAs layers. The results of the BEEM measurements indicate, that the GaAs QWs are defined by AlGaAs barriers. The transition from AlGaAs to GaAs is done within 10 nm. (orig.)

Garbage collector interface

OpenAIRE

Ive, Anders; Blomdell, Anders; Ekman, Torbjörn; Henriksson, Roger; Nilsson, Anders; Nilsson, Klas; Robertz, Sven

2002-01-01

The purpose of the presented garbage collector interface is to provide a universal interface for many different implementations of garbage collectors. This is to simplify the integration and exchange of garbage collectors, but also to support incremental, non-conservative, and thread safe implementations. Due to the complexity of the interface, it is aimed at code generators and preprocessors. Experiences from ongoing implementations indicate that the garbage collector interface successfully ...

An interface energy density-based theory considering the coherent interface effect in nanomaterials

Science.gov (United States)

Yao, Yin; Chen, Shaohua; Fang, Daining

2017-02-01

To characterize the coherent interface effect conveniently and feasibly in nanomaterials, a continuum theory is proposed that is based on the concept of the interface free energy density, which is a dominant factor affecting the mechanical properties of the coherent interface in materials of all scales. The effect of the residual strain caused by self-relaxation and the lattice misfit of nanomaterials, as well as that due to the interface deformation induced by an external load on the interface free energy density is considered. In contrast to the existing theories, the stress discontinuity at the interface is characterized by the interface free energy density through an interface-induced traction. As a result, the interface elastic constant introduced in previous theories, which is not easy to determine precisely, is avoided in the present theory. Only the surface energy density of the bulk materials forming the interface, the relaxation parameter induced by surface relaxation, and the mismatch parameter for forming a coherent interface between the two surfaces are involved. All the related parameters are far easier to determine than the interface elastic constants. The effective bulk and shear moduli of a nanoparticle-reinforced nanocomposite are predicted using the proposed theory. Closed-form solutions are achieved, demonstrating the feasibility and convenience of the proposed model for predicting the interface effect in nanomaterials.

User interface for a partially incompatible system software environment with non-ADP users

Energy Technology Data Exchange (ETDEWEB)

Loffman, R.S.

1987-08-01

Good user interfaces to computer systems and software applications are the result of combining an analysis of user needs with knowledge of interface design principles and techniques. This thesis reports on an interface for an environment: (a) that consists of users who are not computer science or data processing professionals; and (b) which is bound by predetermined software and hardware. The interface was designed which combined these considerations with user interface design principles. Current literature was investigated to establish a baseline of knowledge about user interface design. There are many techniques which can be used to implement a user interface, but all should have the same basic goal, which is to assist the user in the performance of a task. This can be accomplished by providing the user with consistent, well-structured interfaces which also provide flexibility to adapt to differences among users. The interface produced used menu selection and command language techniques to make two different operating system environments appear similar. Additional included features helped to address the needs of different users. The original goal was also to make the transition between the two systems transparent. This was not fully accomplished due to software and hardware limitations.

High-bandwidth memory interface

CERN Document Server

Kim, Chulwoo; Song, Junyoung

2014-01-01

This book provides an overview of recent advances in memory interface design at both the architecture and circuit levels. Coverage includes signal integrity and testing, TSV interface, high-speed serial interface including equalization, ODT, pre-emphasis, wide I/O interface including crosstalk, skew cancellation, and clock generation and distribution. Trends for further bandwidth enhancement are also covered.   • Enables readers with minimal background in memory design to understand the basics of high-bandwidth memory interface design; • Presents state-of-the-art techniques for memory interface design; • Covers memory interface design at both the circuit level and system architecture level.

Object oriented programming interfaces for accelerator control

International Nuclear Information System (INIS)

Hoff, L.T.

1997-01-01

Several years ago, the AGS controls group was given the task of developing software for the RHIC accelerator. Like the AGS, the RHIC control system needs to control and monitor equipment distributed around a relatively large geographic area. A local area network connects this equipment to a collection of UNIX workstations in a central control room. Similar software had been developed for the AGS about a decade earlier, but isn't well suited for RHIC use for a number of reasons. Rather than adapt the AGS software for RHIC use, the controls group opted to start with a clean slate. To develop software that would address the shortcomings of the AGS software, while preserving the useful features that evolved through years of use. A current trend in control system design is to provide an object oriented programming interface for application developers. This talk will discuss important aspects and features of object oriented application programming interfaces (APIs) for accelerator control systems, and explore why such interfaces are becoming the norm

The scalable coherent interface, IEEE P1596

International Nuclear Information System (INIS)

Gustavson, D.B.

1990-01-01

IEEE P1596, the scalable coherent interface (formerly known as SuperBus) is based on experience gained while developing Fastbus (ANSI/IEEE 960--1986, IEC 935), Futurebus (IEEE P896.x) and other modern 32-bit buses. SCI goals include a minimum bandwidth of 1 GByte/sec per processor in multiprocessor systems with thousands of processors; efficient support of a coherent distributed-cache image of distributed shared memory; support for repeaters which interface to existing or future buses; and support for inexpensive small rings as well as for general switched interconnections like Banyan, Omega, or crossbar networks. This paper presents a summary of current directions, reports the status of the work in progress, and suggests some applications in data acquisition and physics

Water at Interfaces

DEFF Research Database (Denmark)

Björneholm, Olle; Hansen, Martin Hangaard; Hodgson, Andrew

2016-01-01

The interfaces of neat water and aqueous solutions play a prominent role in many technological processes and in the environment. Examples of aqueous interfaces are ultrathin water films that cover most hydrophilic surfaces under ambient relative humidities, the liquid/solid interface which drives...

Ionic Structure at Dielectric Interfaces

Science.gov (United States)

Jing, Yufei

increase the electric field near the liquid interface, or can even reverse it locally, at high salt concentrations in the aqueous phase. These observations suggest a novel trapping/release mechanism of charged nanoparticles at oil-water interfaces in the vicinity of the point of zero charge. In addition, we study the effects of size asymmetry and charge asymmetry on ion distribution at a dielectric interface using coarse-grained MD based on an energy variational principle. The goal is to explore charge amplification with exact consideration of surface polarization. We find that both size asymmetry and charge asymmetry lead to charge separation at the interfaces. In addition, charge separation is enhanced by interface polarization. We are currently extending the research to charged interfaces that has broad applications such as batteries and supercapacitors for energy storage.

Aespoe Hard Rock Laboratory. Status Report May - August 2009

International Nuclear Information System (INIS)

2009-11-01

The Aespoe Hard Rock Laboratory (HRL) constitutes an important part of SKB's work to design and construct a geological repository for spent nuclear fuel and to develop and test methods for characterisation of a suitable site. The plans for SKB's research and development of technique during the period 2008-2013 are presented in SKB's RDandD-Programme 2007 /SKB 2007/. The information given in the RDandD-Programme related to Aespoe HRL is annually detailed in the Aespoe HRL Planning Report /SKB 2009/. This Aespoe HRL Status Report is a collection of the main achievements obtained during the period May to August 2009

Aespoe Hard Rock Laboratory. Status Report October - December 2008

International Nuclear Information System (INIS)

2009-03-01

The Aespoe Hard Rock Laboratory (HRL) constitutes an important part of SKB's work to design and construct a geological repository for spent nuclear fuel and to develop and test methods for characterisation of a suitable site. The plans for SKB's research and development of technique during the period 2008-2013 are presented in SKB's RDandD-Programme 2007 /SKB 2007/. The information given in the RDandD-Programme related to Aespoe HRL is annually detailed in the Aespoe HRL Planning Report /SKB 2008/. This Aespoe HRL Status Report is a collection of the main achievements obtained during the fourth quarter of 2008

Aespoe Hard Rock Laboratory. Status Report. September - December 2009

International Nuclear Information System (INIS)

2010-05-01

The Aespoe Hard Rock Laboratory (HRL) constitutes an important part of SKB's work to design and construct a geological repository for spent nuclear fuel and to develop and test methods for characterisation of a suitable site. The plans for SKB's research and development of technique during the period 2008-2013 are presented in SKB's RDandD Programme 2007 /SKB 2007/. The information given in the RDandD-Programme related to Aespoe HRL is annually detailed in the Aespoe HRL Planning Report /SKB 2009/. This Aespoe HRL Status Report is a collection of the main achievements obtained during the period September to December 2009

Aespoe Hard Rock Laboratory. Status Report January - April 2009

International Nuclear Information System (INIS)

2009-09-01

The Aespoe Hard Rock Laboratory (HRL) constitutes an important part of SKB's work to design and construct a geological repository for spent nuclear fuel and to develop and test methods for characterisation of a suitable site. The plans for SKB's research and development of technique during the period 2008-2013 are presented in SKB's RDandD-Programme 2007 /SKB 2007/. The information given in the RDandD-Programme related to Aespoe HRL is annually detailed in the Aespoe HRL Planning Report /SKB 2009/. This Aespoe HRL Status Report is a collection of the main achievements obtained during the period January to April 2009

Aespoe Hard Rock Laboratory. Status Report. April - June 2007

Energy Technology Data Exchange (ETDEWEB)

2007-07-01

The Aespoe Hard Rock Laboratory (HRL) constitutes an important part of SKB's work to design and construct a geological repository for spent nuclear fuel and to develop and test methods for characterisation of a suitable site. The plans for SKB's research and development of technique during the period 2005- 2010 are presented in SKB's RDandD-Programme 2004 /SKB 2004/. The information given in the RDandD-Programme related to Aespoe HRL is annually detailed in the Aespoe HRL Planning Report /SKB 2007/. This Aespoe HRL Status Report is a collection of the main achievements obtained during the second quarter 2007

Aespoe Hard Rock Laboratory. Status Report. April - June 2007

International Nuclear Information System (INIS)

2007-01-01

The Aespoe Hard Rock Laboratory (HRL) constitutes an important part of SKB's work to design and construct a geological repository for spent nuclear fuel and to develop and test methods for characterisation of a suitable site. The plans for SKB's research and development of technique during the period 2005- 2010 are presented in SKB's RDandD-Programme 2004 /SKB 2004/. The information given in the RDandD-Programme related to Aespoe HRL is annually detailed in the Aespoe HRL Planning Report /SKB 2007/. This Aespoe HRL Status Report is a collection of the main achievements obtained during the second quarter 2007

Aespoe Hard Rock Laboratory. Status Report. July - September 2008

International Nuclear Information System (INIS)

2008-01-01

The Aespoe Hard Rock Laboratory (HRL) constitutes an important part of SKB's work to design and construct a geological repository for spent nuclear fuel and to develop and test methods for characterisation of a suitable site. The plans for SKB's research and development of technique during the period 2008-2013 are presented in SKB's RDandD-Programme 2007 /SKB 2007/. The information given in the RDandD-Programme related to Aespoe HRL is annually detailed in the Aespoe HRL Planning Report /SKB 2008/. This Aespoe HRL Status Report is a collection of the main achievements obtained during the third quarter of 2008

Aespoe Hard Rock Laboratory. Status Report. January - April 2010

International Nuclear Information System (INIS)

2010-10-01

The Aespoe Hard Rock Laboratory (HRL) constitutes an important part of SKB's work to design and construct a geological repository for spent nuclear fuel and to develop and test methods for characterisation of a suitable site. The plans for SKB's research and development of technique during the period 2008-2013 are presented in SKB's RDandD Programme 2007 /SKB 2007/. The information given in the RDandD-Programme related to Aespoe HRL is annually detailed in the Aespoe HRL Planning Report /SKB 2009/. This Aespoe HRL Status Report is a collection of the main achievements obtained during the period January to April 2010

Java interface for asserting interactive telerobotic control

Science.gov (United States)

DePasquale, Peter; Lewis, John; Stein, Matthew R.

1997-12-01

Many current web-based telerobotic interfaces use HyperText Markup Language (HTML) forms to assert user control on a robot. While acceptable for some tasks, a Java interface can provide better client-server interaction. The Puma Paint project is a joint effort between the Department of Computing Sciences at Villanova University and the Department of Mechanical and Materials Engineering at Wilkes University. THe project utilizes a Java applet to control a Unimation Puma 1760 robot during the task of painting on a canvas. The interface allows the user to control the paint strokes as well as the pressure of a brush on the canvas and how deep the brush is dipped into a paint jar. To provide immediate feedback, a virtual canvas models the effects of the controls as the artist paints. Live color video feedback is provided, allowing the user to view the actual results of the robot's motions. Unlike the step-at-a-time model of many web forms, the application permits the user to assert interactive control. The greater the complexity of the interaction between the robot and its environment, the greater the need for high quality information presentation to the user. The use of Java allows the sophistication of the user interface to be raised to the level required for satisfactory control. This paper describes the Puma Paint project, including the interface and communications model. It also examines the challenges of using the Internet as the medium of communications and the challenges of encoding free ranging motions for transmission from the client to the robot.

Nano Trek Beyond: Driving Nanocars/Molecular Machines at Interfaces.

Science.gov (United States)

Ariga, Katsuhiko; Mori, Taizo; Nakanishi, Waka

2018-03-09

In 2016, the Nobel Prize in Chemistry was awarded for pioneering work on molecular machines. Half a year later, in Toulouse, the first molecular car race, a "nanocar race", was held by using the tip of a scanning tunneling microscope as an electrical remote control. In this Focus Review, we discuss the current state-of-the-art in research on molecular machines at interfaces. In the first section, we briefly explain the science behind the nanocar race, followed by a selection of recent examples of controlling molecules on surfaces. Finally, motion synchronization and the functions of molecular machines at liquid interfaces are discussed. This new concept of molecular tuning at interfaces is also introduced as a method for the continuous modification and optimization of molecular structure for target functions. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Neuromorphic neural interfaces: from neurophysiological inspiration to biohybrid coupling with nervous systems

Science.gov (United States)

Broccard, Frédéric D.; Joshi, Siddharth; Wang, Jun; Cauwenberghs, Gert

2017-08-01

Objective. Computation in nervous systems operates with different computational primitives, and on different hardware, than traditional digital computation and is thus subjected to different constraints from its digital counterpart regarding the use of physical resources such as time, space and energy. In an effort to better understand neural computation on a physical medium with similar spatiotemporal and energetic constraints, the field of neuromorphic engineering aims to design and implement electronic systems that emulate in very large-scale integration (VLSI) hardware the organization and functions of neural systems at multiple levels of biological organization, from individual neurons up to large circuits and networks. Mixed analog/digital neuromorphic VLSI systems are compact, consume little power and operate in real time independently of the size and complexity of the model. Approach. This article highlights the current efforts to interface neuromorphic systems with neural systems at multiple levels of biological organization, from the synaptic to the system level, and discusses the prospects for future biohybrid systems with neuromorphic circuits of greater complexity. Main results. Single silicon neurons have been interfaced successfully with invertebrate and vertebrate neural networks. This approach allowed the investigation of neural properties that are inaccessible with traditional techniques while providing a realistic biological context not achievable with traditional numerical modeling methods. At the network level, populations of neurons are envisioned to communicate bidirectionally with neuromorphic processors of hundreds or thousands of silicon neurons. Recent work on brain-machine interfaces suggests that this is feasible with current neuromorphic technology. Significance. Biohybrid interfaces between biological neurons and VLSI neuromorphic systems of varying complexity have started to emerge in the literature. Primarily intended as a

X-ray irradiation effects of interface traps and trapped-oxide charge at the Si-SiO{sub 2} interface of segmented silicon sensors

Energy Technology Data Exchange (ETDEWEB)

Kopsalis, Ioannis; Fretwurst, Eckhart; Garutti, Erika; Klanner, Robert; Schwandt, Joern [Institute for Experimental Physics, Hamburg University, Luruper Chaussee 149, D-22761 Hamburg (Germany)

2016-07-01

The surface radiation damage of SiO{sub 2} grown on high-ohmic Si, as used for the fabrication of segmented silicon sensors, has been investigated. Circular p- and n-MOSFETs, biased in accumulation and inversion at a field in the SiO{sub 2} of about 500 kV/cm, have been irradiated by X-rays up to a dose of about 17 kGy(SiO{sub 2}) in different irradiation steps. Before and after each irradiation, the gate voltage has been cycled from inversion to accumulation conditions and back, and from the dependence of the drain-source current, on gate voltage, the threshold voltage of the MOSFET and the hole and electron mobility at the Si-SiO{sub 2} interface determined. From the threshold voltage, the effective oxide-charge density is calculated. Using the subthreshold-current technique the contribution of interface traps, in the lower and the upper part of the energy Si bandgap, and of fixed oxide-charge to the effective oxide-charge density has been estimated. Results on the dose dependence of the above quantities, the charging-up and discharging of border traps when changing the gate voltage, and the hole and electron mobilities at the Si-SiO{sub 2} interface are presented.

HCIDL: Human-computer interface description language for multi-target, multimodal, plastic user interfaces

Directory of Open Access Journals (Sweden)

Lamia Gaouar

2018-06-01

Full Text Available From the human-computer interface perspectives, the challenges to be faced are related to the consideration of new, multiple interactions, and the diversity of devices. The large panel of interactions (touching, shaking, voice dictation, positioning … and the diversification of interaction devices can be seen as a factor of flexibility albeit introducing incidental complexity. Our work is part of the field of user interface description languages. After an analysis of the scientific context of our work, this paper introduces HCIDL, a modelling language staged in a model-driven engineering approach. Among the properties related to human-computer interface, our proposition is intended for modelling multi-target, multimodal, plastic interaction interfaces using user interface description languages. By combining plasticity and multimodality, HCIDL improves usability of user interfaces through adaptive behaviour by providing end-users with an interaction-set adapted to input/output of terminals and, an optimum layout. Keywords: Model driven engineering, Human-computer interface, User interface description languages, Multimodal applications, Plastic user interfaces

LabVIEW Interface for PCI-SpaceWire Interface Card

Science.gov (United States)

Lux, James; Loya, Frank; Bachmann, Alex

2005-01-01

This software provides a LabView interface to the NT drivers for the PCISpaceWire card, which is a peripheral component interface (PCI) bus interface that conforms to the IEEE-1355/ SpaceWire standard. As SpaceWire grows in popularity, the ability to use SpaceWire links within LabVIEW will be important to electronic ground support equipment vendors. In addition, there is a need for a high-level LabVIEW interface to the low-level device- driver software supplied with the card. The LabVIEW virtual instrument (VI) provides graphical interfaces to support all (1) SpaceWire link functions, including message handling and routing; (2) monitoring as a passive tap using specialized hardware; and (3) low-level access to satellite mission-control subsystem functions. The software is supplied in a zip file that contains LabVIEW VI files, which provide various functions of the PCI-SpaceWire card, as well as higher-link-level functions. The VIs are suitably named according to the matching function names in the driver manual. A number of test programs also are provided to exercise various functions.

User Interface History

DEFF Research Database (Denmark)

Jørgensen, Anker Helms; Myers, Brad A

2008-01-01

User Interfaces have been around as long as computers have existed, even well before the field of Human-Computer Interaction was established. Over the years, some papers on the history of Human-Computer Interaction and User Interfaces have appeared, primarily focusing on the graphical interface e...

Natural language interface for nuclear data bases

International Nuclear Information System (INIS)

Heger, A.S.; Koen, B.V.

1987-01-01

A natural language interface has been developed for access to information from a data base, simulating a nuclear plant reliability data system (NPRDS), one of the several existing data bases serving the nuclear industry. In the last decade, the importance of information has been demonstrated by the impressive diffusion of data base management systems. The present methods that are employed to access data bases fall into two main categories of menu-driven systems and use of data base manipulation languages. Both of these methods are currently used by NPRDS. These methods have proven to be tedious, however, and require extensive training by the user for effective utilization of the data base. Artificial intelligence techniques have been used in the development of several intelligent front ends for data bases in nonnuclear domains. Lunar is a natural language program for interface to a data base describing moon rock samples brought back by Apollo. Intellect is one of the first data base question-answering systems that was commercially available in the financial area. Ladder is an intelligent data base interface that was developed as a management aid to Navy decision makers. A natural language interface for nuclear data bases that can be used by nonprogrammers with little or no training provides a means for achieving this goal for this industry

U-Net/SLE: A Java-Based User-Customizable Virtual Network Interface

Directory of Open Access Journals (Sweden)

Matt Welsh

1999-01-01

Full Text Available We describe U‐Net/SLE (Safe Language Extensions, a user‐level network interface architecture which enables per‐application customization of communication semantics through downloading of user extension applets, implemented as Java classfiles, to the network interface. This architecture permits applications to safely specify code to be executed within the NI on message transmission and reception. By leveraging the existing U‐Net model, applications may implement protocol code at the user level, within the NI, or using some combination of the two. Our current implementation, using the Myricom Myrinet interface and a small Java Virtual Machine subset, allows host communication overhead to be reduced and improves the overlap of communication and computation during protocol processing.

Electrochemical ion transfer across liquid/liquid interfaces confined within solid-state micropore arrays--simulations and experiments.

Science.gov (United States)

Strutwolf, Jörg; Scanlon, Micheál D; Arrigan, Damien W M

2009-01-01

Miniaturised liquid/liquid interfaces provide benefits for bioanalytical detection with electrochemical methods. In this work, microporous silicon membranes which can be used for interface miniaturisation were characterized by simulations and experiments. The microporous membranes possessed hexagonal arrays of pores with radii between 10 and 25 microm, a pore depth of 100 microm and pore centre-to-centre separations between 99 and 986 microm. Cyclic voltammetry was used to monitor ion transfer across arrays of micro-interfaces between two immiscible electrolyte solutions (microITIES) formed at these membranes, with the organic phase present as an organogel. The results were compared to computational simulations taking into account mass transport by diffusion and encompassing diffusion to recessed interfaces and overlapped diffusion zones. The simulation and experimental data were both consistent with the situation where the location of the liquid/liquid (l/l) interface was on the aqueous side of the silicon membrane and the pores were filled with the organic phase. While the current for the forward potential scan (transfer of the ion from the aqueous phase to the organic phase) was strongly dependent on the location of the l/l interface, the current peak during the reverse scan (transfer of the ion from the organic phase to the aqueous phase) was influenced by the ratio of the transferring ion's diffusion coefficients in both phases. The diffusion coefficient of the transferring ion in the gelified organic phase was ca. nine times smaller than in the aqueous phase. Asymmetric cyclic voltammogram shapes were caused by the combined effect of non-symmetrical diffusion (spherical and linear) and by the inequality of the diffusion coefficient in both phases. Overlapping diffusion zones were responsible for the observation of current peaks instead of steady-state currents during the forward scan. The characterisation of the diffusion behaviour is an important requirement

Toward best practice in Human Machine Interface design for older drivers: A review of current design guidelines.

Science.gov (United States)

Young, K L; Koppel, S; Charlton, J L

2017-09-01

Older adults are the fastest growing segment of the driving population. While there is a strong emphasis for older people to maintain their mobility, the safety of older drivers is a serious community concern. Frailty and declines in a range of age-related sensory, cognitive, and physical impairments can place older drivers at an increased risk of crash-related injuries and death. A number of studies have indicated that in-vehicle technologies such as Advanced Driver Assistance Systems (ADAS) and In-Vehicle Information Systems (IVIS) may provide assistance to older drivers. However, these technologies will only benefit older drivers if their design is congruent with the complex needs and diverse abilities of this driving cohort. The design of ADAS and IVIS is largely informed by automotive Human Machine Interface (HMI) guidelines. However, it is unclear to what extent the declining sensory, cognitive and physical capabilities of older drivers are addressed in the current guidelines. This paper provides a review of key current design guidelines for IVIS and ADAS with respect to the extent they address age-related changes in functional capacities. The review revealed that most of the HMI guidelines do not address design issues related to older driver impairments. In fact, in many guidelines driver age and sensory cognitive and physical impairments are not mentioned at all and where reference is made, it is typically very broad. Prescriptive advice on how to actually design a system so that it addresses the needs and limitations of older drivers is not provided. In order for older drivers to reap the full benefits that in-vehicle technology can afford, it is critical that further work establish how older driver limitations and capabilities can be supported by the system design process, including their inclusion into HMI design guidelines. Copyright © 2016 Elsevier Ltd. All rights reserved.

Web-Based Interface for Command and Control of Network Sensors

Science.gov (United States)

Wallick, Michael N.; Doubleday, Joshua R.; Shams, Khawaja S.

2010-01-01

This software allows for the visualization and control of a network of sensors through a Web browser interface. It is currently being deployed for a network of sensors monitoring Mt. Saint Helen s volcano; however, this innovation is generic enough that it can be deployed for any type of sensor Web. From this interface, the user is able to fully control and monitor the sensor Web. This includes, but is not limited to, sending "test" commands to individual sensors in the network, monitoring for real-world events, and reacting to those events

Microprocessor interfacing

CERN Document Server

Vears, R E

2014-01-01

Microprocessor Interfacing provides the coverage of the Business and Technician Education Council level NIII unit in Microprocessor Interfacing (syllabus U86/335). Composed of seven chapters, the book explains the foundation in microprocessor interfacing techniques in hardware and software that can be used for problem identification and solving. The book focuses on the 6502, Z80, and 6800/02 microprocessor families. The technique starts with signal conditioning, filtering, and cleaning before the signal can be processed. The signal conversion, from analog to digital or vice versa, is expl

Review of Virtual Environment Interface Technology.

Science.gov (United States)

1996-03-01

seven years. Current work on interfaces for passive motion is focusing on a new breed of motion chairs, which will probably become widely used by the... ophthalmologist . Micro Vision, Inc. intends to enter the market with monochrome displays for applications that need a compact display with minimal power draw...msec. As the computer vision community continues to make advances in algorithms and hardware, the use of computer vision is likely to become prevalent

Development of a Control and Vision Interface for an AR.Drone

Directory of Open Access Journals (Sweden)

Cheema Prasad

2016-01-01

Full Text Available The AR.Drone is a remote controlled quadcopter which is low cost, and readily available for consumers. Therefore it represents a simple test-bed on which control and vision research may be conducted. However, interfacing with the AR.Drone can be a challenge for new researchers as the AR.Drone's application programming interface (API is built on low-level, bit-wise, C instructions. Therefore, this paper will demonstrate the use of an additional layer of abstraction on the AR.Drone’s API via the Robot Operating System (ROS. Using ROS, the construction of a high-level graphical user interface (GUI will be demonstrated, with the explicit aim of assisting new researchers in developing simple control and vision algorithms to interface with the AR.Drone. The GUI, formally known as the Control and Vision Interface (CVI is currently used to research and develop computer vision, simultaneous localisation and mapping (SLAM, and path planning algorithms by a number of postgraduate and undergraduate students at the school of Aeronautical, Mechanical, and Mechatronics Engineering (AMME in The University of Sydney.

SSM's licensing review of a spent nuclear fuel repository in Sweden

International Nuclear Information System (INIS)

Dverstorpand, Bjoern; Stroemberg, Bo

2014-01-01

On 16 March 2011 the Swedish Nuclear Fuel and Waste Management Co. (SKB) submitted license applications for a general license to construct, possess and operate a KBS-3 type spent nuclear fuel repository at the Forsmark site, in Oesthammar municipality, and an encapsulation plant in Oskarshamn municipality. The KBS-3 method, which has been developed by SKB over a period of more than 30 years, entails disposing of the spent fuel in copper canisters, surrounded by a swelling bentonite clay, at about 500 m depth in crystalline basement rock. SKB's applications are being evaluated in parallel by the Swedish Radiation Safety Authority (SSM) according to the Act on Nuclear Activities and by the Land and Environmental Court according to the Environmental Code. During the review SSM will act as an expert review body to the Land and Environmental Court in the areas of radiation protection, safety and security/non-proliferation. Both SSM and the court will produce a statement with a recommendation regarding a licensing decision and licensing conditions to the government. The government will make the final decision after consulting the municipalities concerned by SKB's facilities (municipal veto applies). The current licensing decision is just one of several licensing decisions that will be required for the repository. However it is arguably the most important one, because it is the last licensing stage with a broad societal involvement including an environmental impact assessment (EIA) process, national consultations and municipal veto for the concerned municipalities. The licensing steps to follow, should SKB be granted a license by the government, only require approval by SSM. These steps include application for start of actual construction work, test operation and routine operation. (authors)

Interface Realisms

DEFF Research Database (Denmark)

Pold, Søren

2005-01-01

This article argues for seeing the interface as an important representational and aesthetic form with implications for postmodern culture and digital aesthetics. The interface emphasizes realism due in part to the desire for transparency in Human-Computer Interaction (HCI) and partly...

Temperature dependent current-voltage characteristics of Au/n-Si Schottky barrier diodes and the effect of transition metal oxides as an interface layer

Science.gov (United States)

Mahato, Somnath; Puigdollers, Joaquim

2018-02-01

Temperature dependent current-voltage (I‒V) characteristics of Au/n-type silicon (n-Si) Schottky barrier diodes have been investigated. Three transition metal oxides (TMO) are used as an interface layer between gold and silicon. The basic Schottky diode parameters such as ideality factor (n), barrier height (ϕb 0) and series resistance (Rs) are calculated and successfully explained by the thermionic emission (TE) theory. It has been found that ideality factor decreased and barrier height increased with increased of temperature. The conventional Richardson plot of ln(I0/T2) vs. 1000/T is determined the activation energy (Ea) and Richardson constant (A*). Whereas value of 'A*' is much smaller than the known theoretical value of n-type Si. The temperature dependent I-V characteristics obtained the mean value of barrier height (ϕb 0 bar) and standard deviation (σs) from the linear plot of ϕap vs. 1000/T. From the modified Richardson plot of ln(I0/T2) ˗ (qσ)2/2(kT)2 vs. 1000/T gives Richardson constant and homogeneous barrier height of Schottky diodes. Main observation in this present work is the barrier height and ideality factor shows a considerable change but the series resistance value exhibits negligible change due to TMO as an interface layer.

Interface tuning of current-induced cooling in molecular circuits

Czech Academy of Sciences Publication Activity Database

Foti, Giuseppe; Vázquez, Héctor

2017-01-01

Roč. 121, č. 2 (2017), s. 1082-1088 ISSN 1932-7447 R&D Projects: GA ČR GA15-19672S Institutional support: RVO:68378271 Keywords : current-induced heating and cooling * molecular junction * Carbene Subject RIV: CF - Physical ; Theoretical Chemistry OBOR OECD: Physical chemistry Impact factor: 4.536, year: 2016

Review of Project SAFE: Comments on biosphere conceptual model description and risk assessment methodology

International Nuclear Information System (INIS)

Klos, Richard; Wilmot, Roger

2002-09-01

The Swedish Nuclear Fuel and Waste Management Company's (SKB's) most recent assessment of the safety of the Forsmark repository for low-level and intermediate-level waste (Project SAFE) is currently undergoing review by the Swedish regulators. As part of its review, the Swedish Radiation Protection Institute (SSI) identified that two components of SAFE require more detailed review: (i) the conceptual model description of the biosphere system, and (ii) SKB's risk assessment methodology. We have reviewed the biosphere system interaction matrix and how this has been used in the identification, justification and description of biosphere models for radiological assessment purposes. The risk assessment methodology has been reviewed considering in particular issues associated with scenario selection, assessment timescale, and the probability and risk associated with the well scenario. There is an extensive range of supporting information on which biosphere modelling in Project SAFE is based. However, the link between this material and the biosphere models themselves is not clearly set out. This leads to some contradictions and mis-matches between description and implementation. One example concerns the representation of the geosphere-biosphere interface. The supporting description of lakes indicates that interaction between groundwaters entering the biosphere through lake bed sediments could lead to accumulations of radionuclides in sediments. These sediments may become agricultural areas at some time in the future. In the numerical modelling of the biosphere carried out in Project SAFE, the direct accumulation of contaminants in bed sediments is not represented. Application of a more rigorous procedure to ensure numerical models are fit for purpose is recommended, paying more attention to issues associated with the geosphere-biosphere interface. A more structured approach to risk assessment would be beneficial, with a better explanation of the difference between

Atomistic simulations of contact area and conductance at nanoscale interfaces.

Science.gov (United States)

Hu, Xiaoli; Martini, Ashlie

2017-11-09

Atomistic simulations were used to study conductance across the interface between a nanoscale gold probe and a graphite surface with a step edge. Conductance on the graphite terrace was observed to increase with load and be approximately proportional to contact area calculated from the positions of atoms in the interface. The relationship between area and conductance was further explored by varying the position of the contact relative to the location of the graphite step edge. These simulations reproduced a previously-reported current dip at step edges measured experimentally and the trend was explained by changes in both contact area and the distribution of distances between atoms in the interface. The novel approach reported here provides a foundation for future studies of the fundamental relationships between conductance, load and surface topography at the atomic scale.

Easy-to-use interface

International Nuclear Information System (INIS)

Blattner, D O; Blattner, M M; Tong, Y.

1999-01-01

Easy-to-use interfaces are a class of interfaces that fall between public access interfaces and graphical user interfaces in usability and cognitive difficulty. We describe characteristics of easy-to-use interfaces by the properties of four dimensions: selection, navigation, direct manipulation, and contextual metaphors. Another constraint we introduced was to include as little text as possible, and what text we have will be in at least four languages. Formative evaluations were conducted to identify and isolate these characteristics. Our application is a visual interface for a home automation system intended for a diverse set of users. The design will be expanded to accommodate the visually disabled in the near future

Aespoe Hard Rock Laboratory. Status Report January - April 2009

Energy Technology Data Exchange (ETDEWEB)

2009-09-15

The Aespoe Hard Rock Laboratory (HRL) constitutes an important part of SKB's work to design and construct a geological repository for spent nuclear fuel and to develop and test methods for characterisation of a suitable site. The plans for SKB's research and development of technique during the period 2008-2013 are presented in SKB's RDandD-Programme 2007 /SKB 2007/. The information given in the RDandD-Programme related to Aespoe HRL is annually detailed in the Aespoe HRL Planning Report /SKB 2009/. This Aespoe HRL Status Report is a collection of the main achievements obtained during the period January to April 2009.

Aespoe Hard Rock Laboratory. Status Report October - December 2008

Energy Technology Data Exchange (ETDEWEB)

2009-03-15

The Aespoe Hard Rock Laboratory (HRL) constitutes an important part of SKB's work to design and construct a geological repository for spent nuclear fuel and to develop and test methods for characterisation of a suitable site. The plans for SKB's research and development of technique during the period 2008-2013 are presented in SKB's RDandD-Programme 2007 /SKB 2007/. The information given in the RDandD-Programme related to Aespoe HRL is annually detailed in the Aespoe HRL Planning Report /SKB 2008/. This Aespoe HRL Status Report is a collection of the main achievements obtained during the fourth quarter of 2008.

Aespoe Hard Rock Laboratory. Status Report. September - December 2009

Energy Technology Data Exchange (ETDEWEB)

2010-05-15

The Aespoe Hard Rock Laboratory (HRL) constitutes an important part of SKB's work to design and construct a geological repository for spent nuclear fuel and to develop and test methods for characterisation of a suitable site. The plans for SKB's research and development of technique during the period 2008-2013 are presented in SKB's RDandD Programme 2007 /SKB 2007/. The information given in the RDandD-Programme related to Aespoe HRL is annually detailed in the Aespoe HRL Planning Report /SKB 2009/. This Aespoe HRL Status Report is a collection of the main achievements obtained during the period September to December 2009

Aespoe Hard Rock Laboratory. Status Report. January - April 2010

Energy Technology Data Exchange (ETDEWEB)

2010-10-15

The Aespoe Hard Rock Laboratory (HRL) constitutes an important part of SKB's work to design and construct a geological repository for spent nuclear fuel and to develop and test methods for characterisation of a suitable site. The plans for SKB's research and development of technique during the period 2008-2013 are presented in SKB's RDandD Programme 2007 /SKB 2007/. The information given in the RDandD-Programme related to Aespoe HRL is annually detailed in the Aespoe HRL Planning Report /SKB 2009/. This Aespoe HRL Status Report is a collection of the main achievements obtained during the period January to April 2010

Aespoe Hard Rock Laboratory. Status Report May - August 2009

Energy Technology Data Exchange (ETDEWEB)

2009-11-15

The Aespoe Hard Rock Laboratory (HRL) constitutes an important part of SKB's work to design and construct a geological repository for spent nuclear fuel and to develop and test methods for characterisation of a suitable site. The plans for SKB's research and development of technique during the period 2008-2013 are presented in SKB's RDandD-Programme 2007 /SKB 2007/. The information given in the RDandD-Programme related to Aespoe HRL is annually detailed in the Aespoe HRL Planning Report /SKB 2009/. This Aespoe HRL Status Report is a collection of the main achievements obtained during the period May to August 2009.

Aespoe Hard Rock Laboratory. Status Report May - August 2010

Energy Technology Data Exchange (ETDEWEB)

2011-02-15

The Aespoe Hard Rock Laboratory (HRL) constitutes an important part of SKB's work to design and construct a geological repository for spent nuclear fuel and to develop and test methods for characterisation of a suitable site. The plans for SKB's research and development of technique during the period 2008-2013 are presented in SKB's RDandD-Programme 2007 /SKB 2007/. The information given in the RD and D-Programme related to Aespoe HRL is annually detailed in the Aespoe HRL Planning Report /SKB 2010/. This Aespoe HRL Status Report is a collection of the main achievements obtained during the period May to August 2010.

Aespoe Hard Rock Laboratory. Status Report. April - June 2007

Energy Technology Data Exchange (ETDEWEB)

2007-07-01

The Aespoe Hard Rock Laboratory (HRL) constitutes an important part of SKB's work to design and construct a geological repository for spent nuclear fuel and to develop and test methods for characterisation of a suitable site. The plans for SKB's research and development of technique during the period 2005- 2010 are presented in SKB's RDandD-Programme 2004 /SKB 2004/. The information given in the RDandD-Programme related to Aespoe HRL is annually detailed in the Aespoe HRL Planning Report /SKB 2007/. This Aespoe HRL Status Report is a collection of the main achievements obtained during the second quarter 2007

Aespoe Hard Rock Laboratory. Status Report May - August 2010

International Nuclear Information System (INIS)

2011-02-01

The Aespoe Hard Rock Laboratory (HRL) constitutes an important part of SKB's work to design and construct a geological repository for spent nuclear fuel and to develop and test methods for characterisation of a suitable site. The plans for SKB's research and development of technique during the period 2008-2013 are presented in SKB's RDandD-Programme 2007 /SKB 2007/. The information given in the RD and D-Programme related to Aespoe HRL is annually detailed in the Aespoe HRL Planning Report /SKB 2010/. This Aespoe HRL Status Report is a collection of the main achievements obtained during the period May to August 2010

Aespoe Hard Rock Laboratory. Status Report. July - September 2008

Energy Technology Data Exchange (ETDEWEB)

2008-07-01

The Aespoe Hard Rock Laboratory (HRL) constitutes an important part of SKB's work to design and construct a geological repository for spent nuclear fuel and to develop and test methods for characterisation of a suitable site. The plans for SKB's research and development of technique during the period 2008-2013 are presented in SKB's RDandD-Programme 2007 /SKB 2007/. The information given in the RDandD-Programme related to Aespoe HRL is annually detailed in the Aespoe HRL Planning Report /SKB 2008/. This Aespoe HRL Status Report is a collection of the main achievements obtained during the third quarter of 2008.

Independent Calculations for the SR Can Assessment. External review contribution in support of SKI's and SSI's review of SR-Can

Energy Technology Data Exchange (ETDEWEB)

Maul, Philip; Robinson, Peter; Bond, Alex; Benbow, Steven (Quintessa Limited, Henley-on-Thames (GB))

2008-03-15

SKB has published the SR-Can assessment of a deep repository for spent fuel at either the Forsmark or Laxemar sites. This is the final assessment prior to a formal regulatory submission. A number of independent calculations have been undertaken in support of SKI's review of SR-Can. The types of calculations are: 1. direct checks of specified SKB calculations; 2. reproduction of SKB computer calculations with independent codes, to ensure that what SKB has done is properly understood, and to check that the calculations are properly documented; and 3. independent calculations to investigate particular aspects of the safety case. The data used by SKB in its Performance Assessment calculations have not been subject to detailed review. The independent calculations provide information on: 1. where independent calculations have been able to provide support for the arguments put forward by SKB; 2. areas where insufficient information has been provided by SKB to enable a third party to reproduce the SR-Can calculations; and 3. areas where calculations lead to questions about the validity of SKB's arguments. The timescale for the production of the present report has been determined by the timescales for SKI's review of the SR-Can assessment. As a result, some of the independent calculations referred to have not been fully documented, and this will be carried out in 2008. The following conclusions have been drawn. 1. SKB has worked hard to respond to criticisms of previous performance assessments, and SR-Can is an impressive piece of work. 2. In several areas either insufficient or inconsistent information has been presented so that a full reproduction of SKB's calculations has not been possible. This is an important area where SKB will need to improve the presentation of its assessment for SR-Site. 3. There are several areas where SKB's description of post-closure repository evolution needs to be further reviewed. Overall SKB have given only limited

An associative Brain-Computer-Interface for acute stroke patients

DEFF Research Database (Denmark)

Mrachacz-Kersting, Natalie; Stevenson, Andrew James Thomas; Aliakbaryhosseinabadi, Susan

2016-01-01

An efficient innovative Brain-Computer-Interface system that empowers chronic stroke patients to control an artificial activation of their lower limb muscle through task specific motor intent has been tested in the past. In the current study it was applied to acute stroke patients. The system...

Evaluating effect of surface state density at the interfaces in degraded bulk heterojunction organic solar cell

International Nuclear Information System (INIS)

Arora, Swati; Singh, Vinamrita; Arora, Manoj; Pal Tandon, Ram

2012-01-01

Degradation and short shelf life have been observed experimentally in poly(3-hexylthiophene) (P3HT): 6,6-phenyl C61-butyric acid methyl ester (PCBM) based blend solar cells. Both dark and illuminated current-voltage characteristics could be explained quantitatively with a proposed single model for a typical degraded organic solar cell-glass/ITO/PEDOT:PSS/P3HT:PCBM/Al. It has been found that surface state density, interface thickness, tunneling coefficient and occupation probabilities of the interface states becomes important with the passage of time. To look into the problem the activity at ITO/PEDOT:PSS and P3HT:PCBM/Al interfaces are studied using realistic values of the interfaces. The experimental J-V characteristics is well explained with the inclusion of tunneling current through these surface states and becomes the dominant current component for the degraded cell. It is also found that surface state density increases to 10 12 -10 13 cm -2 eV -1 , which has been verified with C-V measurements and also is in agreement with our proposed model for BHJ solar cell after 150 h of fabrication.

Evaluating effect of surface state density at the interfaces in degraded bulk heterojunction organic solar cell

Energy Technology Data Exchange (ETDEWEB)

Arora, Swati, E-mail: drswatia@yahoo.com [Department of Physics, Zakir Husain College, University of Delhi, Delhi 110002 (India); Singh, Vinamrita [Department of Physics and Astrophysics, University of Delhi, Delhi 110007 (India); Arora, Manoj [Department of Physics, Ramjas College, University of Delhi, Delhi 110007 (India); Pal Tandon, Ram [Department of Physics and Astrophysics, University of Delhi, Delhi 110007 (India)

2012-08-01

Degradation and short shelf life have been observed experimentally in poly(3-hexylthiophene) (P3HT): 6,6-phenyl C61-butyric acid methyl ester (PCBM) based blend solar cells. Both dark and illuminated current-voltage characteristics could be explained quantitatively with a proposed single model for a typical degraded organic solar cell-glass/ITO/PEDOT:PSS/P3HT:PCBM/Al. It has been found that surface state density, interface thickness, tunneling coefficient and occupation probabilities of the interface states becomes important with the passage of time. To look into the problem the activity at ITO/PEDOT:PSS and P3HT:PCBM/Al interfaces are studied using realistic values of the interfaces. The experimental J-V characteristics is well explained with the inclusion of tunneling current through these surface states and becomes the dominant current component for the degraded cell. It is also found that surface state density increases to 10{sup 12}-10{sup 13} cm{sup -2} eV{sup -1}, which has been verified with C-V measurements and also is in agreement with our proposed model for BHJ solar cell after 150 h of fabrication.

LANMAS core: Update and current directions

International Nuclear Information System (INIS)

Claborn, J.

1995-01-01

Local Area Network Material Accountability system (LANMAS) core software provides the framework of a material accountability system. It tracks the movement of material throughout a site and generates the required material accountability reports. LANMAS is a net-work- based nuclear material accountability system that runs in a client/server mode. The database of material type and location resides on the server, while the user interface runs on the client. The user interface accesses the data stored on the server via a network. The LANMAS core can be used as the foundation for building required materials control and accountability (MCA) functionality at any site requiring a new MCA system. An individual site will build on the LANMAS core by supplying site-specific software. This paper will provide an update on the current LANMAS development activities and discuss the current direction of the LANMAS project

User interface design principles for the SSM/PMAD automated power system

International Nuclear Information System (INIS)

Jakstas, L.M.; Myers, C.J.

1991-01-01

Computer-human interfaces are an integral part of developing software for spacecraft power systems. A well designed and efficient user interface enables an engineer to effectively operate the system, while it concurrently prevents the user from entering data which is beyond boundary conditions or performing operations which are out of context. A user interface should also be designed to ensure that the engineer easily obtains all useful and critical data for operating the system and is aware of all faults and states in the system. Martin Marietta, under contract to NASA George C. Marshall Space Flight Center, has developed a user interface for the Space Station Module Power Management and Distribution (SSM/PMAD) automated power system testbed which provides human access to the functionality of the power system, as well as exemplifying current techniques in user interface design. The testbed user interface was designed to enable an engineer to operate the system easily without having significant knowledge of computer systems, as well as provide an environment in which the engineer can monitor and interact with the SSM/PMAD system hardware. The design of the interface supports a global view of the most important data form the various hardware and software components, as well as enabling the user to obtain additional or more detailed data when needed. The components and representations of the SSM/PMAD testbed user interface are examined in this paper. An engineer's interactions with the system are also described

Organic interfaces

NARCIS (Netherlands)

Poelman, W.A.; Tempelman, E.

2014-01-01

This paper deals with the consequences for product designers resulting from the replacement of traditional interfaces by responsive materials. Part 1 presents a theoretical framework regarding a new paradigm for man-machine interfacing. Part 2 provides an analysis of the opportunities offered by new

im4Things: An Ontology-Based Natural Language Interface for Controlling Devices in the Internet of Things

KAUST Repository

Noguera-Arnaldos, José Á ngel; Paredes-Valverde, Mario André s; Salas-Zá rate, Marí a Pilar; Rodriguez-Garcia, Miguel Angel; Valencia-Garcí a, Rafael; Ochoa, José Luis

2017-01-01

. However, the IoT also introduces new challenges, some of which arise from the large range of devices currently available and the heterogeneous interfaces provided for their control. The control and management of this variety of devices and interfaces

Configurations of NPD : production interfaces and interface integration mechanisms

NARCIS (Netherlands)

Smulders, F.E.H.M.; Boer, H.; Hansen, P.H.K.; Gubi, E.; Dorst, C.H.

2002-01-01

This paper describes and illustrates different configurations of the interface between new product development and production processes, including both intra–firm and inter–firm interfaces. These configurations are partly based on a process view of product innovation and partly on a structural view

The strength of polyaxial locking interfaces of distal radius plates.

Science.gov (United States)

Hoffmeier, Konrad L; Hofmann, Gunther O; Mückley, Thomas

2009-10-01

Currently available polyaxial locking plates represent the consequent enhancement of fixed-angle, first-generation locking plates. In contrast to fixed-angle locking plates which are sufficiently investigated, the strength of the new polyaxial locking options has not yet been evaluated biomechanically. This study investigates the mechanical strength of single polyaxial interfaces of different volar radius plates. Single screw-plate interfaces of the implants Palmar 2.7 (Königsee Implantate und Instrumente zur Osteosynthese GmbH, Allendorf, Germany), VariAx (Stryker Leibinger GmbH & Co. KG, Freiburg, Germany) und Viper (Integra LifeSciences Corporation, Plainsboro, NJ, USA) were tested by cantilever bending. The strength of 0 degrees, 10 degrees and 20 degrees screw locking angle was obtained during static and dynamic loading. The Palmar 2.7 interfaces showed greater ultimate strength and fatigue strength than the interfaces of the other implants. The strength of the VariAx interfaces was about 60% of Palmar 2.7 in both, static and dynamic loading. No dynamic testing was applied to the Viper plate because of its low ultimate strength. By static loading, an increase in screw locking angle caused a reduction of strength for the Palmar 2.7 and Viper locking interfaces. No influence was observed for the VariAx locking interfaces. During dynamic loading; angulation had no influence on the locking strength of Palmar 2.7. However, reduction of locking strength with increasing screw angulation was observed for VariAx. The strength of the polyaxial locking interfaces differs remarkably between the examined implants. Depending on the implant an increase of the screw locking angle causes a reduction of ultimate or fatigue strength, but not in all cases a significant impact was observed.

The role of spin–orbit coupling in topologically protected interface states in Dirac materials

International Nuclear Information System (INIS)

Abergel, D S L; Balatsky, Alexander V; Edge, Jonathan M

2014-01-01

We highlight the fact that two-dimensional (2D) materials with Dirac-like low energy band structures and spin–orbit coupling (SOC) will produce linearly dispersing topologically protected Jackiw–Rebbi modes at interfaces where the Dirac mass changes sign. These modes may support persistent spin or valley currents parallel to the interface, and the exact arrangement of such topologically protected currents depends crucially on the details of the SOC in the material. As examples, we discuss buckled 2D hexagonal lattices such as silicene or germanene, and transition metal dichalcogenides such as MoS 2 . (paper)

International workshop on site investigation and evaluation based on the siting process in Sweden

International Nuclear Information System (INIS)

Andersson, Johan; Stroem, A.

2001-06-01

SKB's goal is to commence surface based site investigations in 2002. Extensive preparations are now being made for this transition to the next phase in the siting process for the deep repository for spent nuclear fuel. The purpose of the international workshop on site characterisation held at Aespoe April 2001 was to: present the SKB site investigation and evaluation programme to a group of international experts; discuss whether the available toolbox of investigation methods for surface based site investigations is appropriate and state-of-the-art in an international perspective; and by working group sessions discuss the level of ambition in the programme for site investigation for each discipline. This report summarises the conclusions of the workshop in general terms. Many of the detailed comments and ideas obtained at the workshop have already inspired and will also directly inspire the on-going planning work for site characterisation. The core activity at the workshop was the work performed by working groups. They addressed what should be considered for a site characterisation programme, based on the generic planning made so far by SKB. The working groups also outlined site specific characterisation programmes for the sites suggested by SKB. The tasks were strictly confined to technical and scientific modelling issues. The working group chairmen presented the working group results at the workshop and have also submitted short memos to SKB. The present document is a compilation of these memos. The SKB generic programme as presented in the existing top level documents, 'Requirements and Criteria and Overall Programme', received general endorsement and was appreciated for being comprehensive and systematic. For example, it contains comprehensive lists of parameters to be measured. However, there is need for prioritisation and sequencing. This is actually included in the current planning process at SKB where the generic programme later this year will be adapted to

An Approach to Interface Synthesis

DEFF Research Database (Denmark)

Madsen, Jan; Hald, Bjarne

1995-01-01

Presents a novel interface synthesis approach based on a one-sided interface description. Whereas most other approaches consider interface synthesis as optimizing a channel to existing client/server modules, we consider the interface synthesis as part of the client/server module synthesis (which...... may contain the re-use of existing modules). The interface synthesis approach describes the basic transformations needed to transform the server interface description into an interface description on the client side of the communication medium. The synthesis approach is illustrated through a point...

Flexible Compensation of Voltage and Current Unbalance and Harmonics in Microgrids

DEFF Research Database (Denmark)

Mousazadeh, Seyyed Yousef; Jalilian, Alireza; Savaghebi, Mehdi

2017-01-01

In recent years, the harmonics and unbalance problem endanger the voltage and current quality of power systems due to increasing usage of nonlinear and unbalance loads. Using DG interfacing inverters is proposed for voltage or current compensation. In this paper, a flexible control method...... is proposed to compensate voltage and current unbalance and harmonics using the Distributed Generation (DG) interfacing inverters. This method is applicable to both grid-connected and islanded microgrids. In the proposed method, not only the proper control of active and reactive powers can be achieved......) frame. An extensive simulation study has been performed and the results demonstrate the effectiveness of the proposed control scheme. The results show that depending on the compensation mode, the harmonics and unbalance compensation of DGs’ output current, MG’s injected current to the grid as well...

Investigation of the interface region between a porous silicon layer and a silicon substrate

International Nuclear Information System (INIS)

Lee, Ki-Won; Park, Dae-Kyu; Kim, Young-You; Shin, Hyun-Joon

2005-01-01

Atomic force microscopy (AFM) measurement and X-ray diffraction (XRD) analysis were performed to investigate the physical and structural characteristics of the interface region between a porous silicon layer and a silicon substrate. We discovered that, when anodization time was increased under a constant current density, the Si crystallites in the interface region became larger and formed different lattice parameters than observed in the porous silicon layer. Secondary ion mass spectrometry (SIMS) analysis also revealed that the Si was more concentrated in the interface region than in the porous silicon layer. These results were interpreted by the deficiency of the HF solution in reaching to the interface through the pores during the porous silicon formation

Semiconductor/dielectric interface engineering and characterization

Science.gov (United States)

Lucero, Antonio T.

The focus of this dissertation is the application and characterization of several, novel interface passivation techniques for III-V semiconductors, and the development of an in-situ electrical characterization. Two different interface passivation techniques were evaluated. The first is interface nitridation using a nitrogen radical plasma source. The nitrogen radical plasma generator is a unique system which is capable of producing a large flux of N-radicals free of energetic ions. This was applied to Si and the surface was studied using x-ray photoelectron spectroscopy (XPS). Ultra-thin nitride layers could be formed from 200-400° C. Metal-oxide-semiconductor capacitors (MOSCAPs) were fabricated using this passivation technique. Interface nitridation was able to reduce leakage current and improve the equivalent oxide thickness of the devices. The second passivation technique studied is the atomic layer deposition (ALD) diethylzinc (DEZ)/water treatment of sulfur treated InGaAs and GaSb. On InGaAs this passivation technique is able to chemically reduce higher oxidation states on the surface, and the process results in the deposition of a ZnS/ZnO interface passivation layer, as determined by XPS. Capacitance-voltage (C-V) measurements of MOSCAPs made on p-InGaAs reveal a large reduction in accumulation dispersion and a reduction in the density of interfacial traps. The same technique was applied to GaSb and the process was studied in an in-situ half-cycle XPS experiment. DEZ/H2O is able to remove all Sb-S from the surface, forming a stable ZnS passivation layer. This passivation layer is resistant to further reoxidation during dielectric deposition. The final part of this dissertation is the design and construction of an ultra-high vacuum cluster tool for in-situ electrical characterization. The system consists of three deposition chambers coupled to an electrical probe station. With this setup, devices can be processed and subsequently electrically characterized

Touchfree medical interfaces.

Science.gov (United States)

Rossol, Nathaniel; Cheng, Irene; Rui Shen; Basu, Anup

2014-01-01

Real-time control of visual display systems via mid-air hand gestures offers many advantages over traditional interaction modalities. In medicine, for example, it allows a practitioner to adjust display values, e.g. contrast or zoom, on a medical visualization interface without the need to re-sterilize the interface. However, when users are holding a small tool (such as a pen, surgical needle, or computer stylus) the need to constantly put the tool down in order to make hand gesture interactions is not ideal. This work presents a novel interface that automatically adjusts for gesturing with hands and hand-held tools to precisely control medical displays. The novelty of our interface is that it uses a single set of gestures designed to be equally effective for fingers and hand-held tools without using markers. This type of interface was previously not feasible with low-resolution depth sensors such as Kinect, but is now achieved by using the recently released Leap Motion controller. Our interface is validated through a user study on a group of people given the task of adjusting parameters on a medical image.

Diffusion between evolving interfaces

International Nuclear Information System (INIS)

Juntunen, Janne; Merikoski, Juha

2010-01-01

Diffusion in an evolving environment is studied by continuous-time Monte Carlo simulations. Diffusion is modeled by continuous-time random walkers on a lattice, in a dynamic environment provided by bubbles between two one-dimensional interfaces driven symmetrically towards each other. For one-dimensional random walkers constrained by the interfaces, the bubble size distribution dominates diffusion. For two-dimensional random walkers, it is also controlled by the topography and dynamics of the interfaces. The results of the one-dimensional case are recovered in the limit where the interfaces are strongly driven. Even with simple hard-core repulsion between the interfaces and the particles, diffusion is found to depend strongly on the details of the dynamical rules of particles close to the interfaces.

Combinatorial Nano-Bio Interfaces.

Science.gov (United States)

Cai, Pingqiang; Zhang, Xiaoqian; Wang, Ming; Wu, Yun-Long; Chen, Xiaodong

2018-06-08

Nano-bio interfaces are emerging from the convergence of engineered nanomaterials and biological entities. Despite rapid growth, clinical translation of biomedical nanomaterials is heavily compromised by the lack of comprehensive understanding of biophysicochemical interactions at nano-bio interfaces. In the past decade, a few investigations have adopted a combinatorial approach toward decoding nano-bio interfaces. Combinatorial nano-bio interfaces comprise the design of nanocombinatorial libraries and high-throughput bioevaluation. In this Perspective, we address challenges in combinatorial nano-bio interfaces and call for multiparametric nanocombinatorics (composition, morphology, mechanics, surface chemistry), multiscale bioevaluation (biomolecules, organelles, cells, tissues/organs), and the recruitment of computational modeling and artificial intelligence. Leveraging combinatorial nano-bio interfaces will shed light on precision nanomedicine and its potential applications.

Engineering Musculoskeletal Tissue Interfaces

Directory of Open Access Journals (Sweden)

Ece Bayrak

2018-04-01

Full Text Available Tissue engineering aims to bring together biomaterials, cells, and signaling molecules within properly designed microenvironments in order to create viable treatment options for the lost or malfunctioning tissues. Design and production of scaffolds and cell-laden grafts that mimic the complex structural and functional features of tissues are among the most important elements of tissue engineering strategy. Although all tissues have their own complex structure, an even more complex case in terms of engineering a proper carrier material is encountered at the tissue interfaces, where two distinct tissues come together. The interfaces in the body can be examined in four categories; cartilage-bone and ligament-bone interfaces at the knee and the spine, tendon-bone interfaces at the shoulder and the feet, and muscle-tendon interface at the skeletal system. These interfaces are seen mainly at the soft-to-hard tissue transitions and they are especially susceptible to injury and tear due to the biomechanical inconsistency between these tissues where high strain fields are present. Therefore, engineering the musculoskeletal tissue interfaces remain a challenge. This review focuses on recent advancements in strategies for musculoskeletal interface engineering using different biomaterial-based platforms and surface modification techniques.

Secure Web-based Ground System User Interfaces over the Open Internet

Science.gov (United States)

Langston, James H.; Murray, Henry L.; Hunt, Gary R.

1998-01-01

A prototype has been developed which makes use of commercially available products in conjunction with the Java programming language to provide a secure user interface for command and control over the open Internet. This paper reports successful demonstration of: (1) Security over the Internet, including encryption and certification; (2) Integration of Java applets with a COTS command and control product; (3) Remote spacecraft commanding using the Internet. The Java-based Spacecraft Web Interface to Telemetry and Command Handling (Jswitch) ground system prototype provides these capabilities. This activity demonstrates the use and integration of current technologies to enable a spacecraft engineer or flight operator to monitor and control a spacecraft from a user interface communicating over the open Internet using standard World Wide Web (WWW) protocols and commercial off-the-shelf (COTS) products. The core command and control functions are provided by the COTS Epoch 2000 product. The standard WWW tools and browsers are used in conjunction with the Java programming technology. Security is provided with the current encryption and certification technology. This system prototype is a step in the direction of giving scientist and flight operators Web-based access to instrument, payload, and spacecraft data.

Aespoe Hard Rock Laboratory. Status Report. September - December 2010

International Nuclear Information System (INIS)

2011-04-01

The Aespoe Hard Rock Laboratory (HRL) constitutes an important part of SKB's work to design and construct a geological repository for spent nuclear fuel and to develop and test methods for characterisation of a suitable site. In September 2010, the plans for SKB's research and development of technique during the period 2011-2016 were presented in SKB's RDandD-Programme 2010 /SKB 2010a/. The information given in the RDandD-Programme related to Aespoe HRL is annually detailed in the Aespoe HRL Planning Report and the information valid for 2010 is given in /SKB 2010b/. This Aespoe HRL Status Report is a collection of the main achievements obtained during the period September to December 2010

Aerobic methanotrophic communities at the Red Sea brine-seawater interface

Directory of Open Access Journals (Sweden)

Rehab Z. Abdallah

2014-09-01

Full Text Available The central rift of the Red Sea contains 25 brine pools with different physicochemical conditions, dictating the diversity and abundance of the microbial community. Three of these pools, the Atlantis II, Kebrit and Discovery Deeps, are uniquely characterized by a high concentration of hydrocarbons. The brine-seawater interface, described as an anoxic-oxic (brine-seawater boundary, is characterized by a high methane concentration, thus favoring aerobic methane oxidation. The current study analyzed the aerobic free–living methane-oxidizing bacterial communities that potentially contribute to methane oxidation at the brine-seawater interfaces of the three aforementioned brine pools, using metagenomic pyrosequencing, 16S rRNA pyrotags and pmoA library constructs. The sequencing of 16S rRNA pyrotags revealed that these interfaces are characterized by high microbial community diversity. Signatures of aerobic methane-oxidizing bacteria were detected in the Atlantis II Interface (ATII-I and the Kebrit Deep Upper (KB-U and Lower (KB-L brine-seawater interfaces. Through phylogenetic analysis of pmoA, we further demonstrated that the ATII-I aerobic methanotroph community is highly diverse. We propose four ATII-I pmoA clusters. Most importantly, cluster 2 groups with marine methane seep methanotrophs, and cluster 4 represent a unique lineage of an uncultured bacterium with divergent alkane monooxygenases. Moreover, non-metric multidimensional scaling (NMDS based on the ordination of putative enzymes involved in methane metabolism showed that the Kebrit interface layers were distinct from the ATII-I and DD-I brine-seawater interfaces.

Investigating Effects of Screen Layout Elements on Interface and Screen Design Aesthetics

OpenAIRE

Altaboli, Ahamed; Lin, Yingzi

2011-01-01

A recent study suggested the use of the screen layout elements of balance, unity, and sequence as a part of a computational model of interface aesthetics. It is argued that these three elements are the most contributed terms in the model. In the current study, a controlled experiment was designed and conducted to systematically investigate effects of these three elements (balance, unity, and sequence) on the perceived interface aesthetics. Results showed that the three elements have signific...

Dynamic Distribution and Layouting of Model-Based User Interfaces in Smart Environments

Science.gov (United States)

Roscher, Dirk; Lehmann, Grzegorz; Schwartze, Veit; Blumendorf, Marco; Albayrak, Sahin

The developments in computer technology in the last decade change the ways of computer utilization. The emerging smart environments make it possible to build ubiquitous applications that assist users during their everyday life, at any time, in any context. But the variety of contexts-of-use (user, platform and environment) makes the development of such ubiquitous applications for smart environments and especially its user interfaces a challenging and time-consuming task. We propose a model-based approach, which allows adapting the user interface at runtime to numerous (also unknown) contexts-of-use. Based on a user interface modelling language, defining the fundamentals and constraints of the user interface, a runtime architecture exploits the description to adapt the user interface to the current context-of-use. The architecture provides automatic distribution and layout algorithms for adapting the applications also to contexts unforeseen at design time. Designers do not specify predefined adaptations for each specific situation, but adaptation constraints and guidelines. Furthermore, users are provided with a meta user interface to influence the adaptations according to their needs. A smart home energy management system serves as running example to illustrate the approach.

Utility Interfaced Pulse-Width Modulation of Solar Fed Voltage ...

African Journals Online (AJOL)

Utility Interfaced Pulse-Width Modulation of Solar Fed Voltage Source Inverter Using Fixed-Band Hysteresis Current Controller Method. ... with the conversion of solar energy into electrical energy; boosting the dc power; inversion of the dc to ac and then synchronization of the inverter output with the utility, and consequently, ...

Helping Students Test Programs That Have Graphical User Interfaces

Directory of Open Access Journals (Sweden)

Matthew Thornton

2008-08-01

Full Text Available Within computer science education, many educators are incorporating software testing activities into regular programming assignments. Tools like JUnit and its relatives make software testing tasks much easier, bringing them into the realm of even introductory students. At the same time, many introductory programming courses are now including graphical interfaces as part of student assignments to improve student interest and engagement. Unfortunately, writing software tests for programs that have significant graphical user interfaces is beyond the skills of typical students (and many educators. This paper presents initial work at combining educationally oriented and open-source tools to create an infrastructure for writing tests for Java programs that have graphical user interfaces. Critically, these tools are intended to be appropriate for introductory (CS1/CS2 student use, and to dovetail with current teaching approaches that incorporate software testing in programming assignments. We also include in our findings our proposed approach to evaluating our techniques.

Lifetime improvement mechanism in organic light-emitting diodes with mixed materials at a heterojunction interface

Science.gov (United States)

Minagawa, Masahiro; Takahashi, Noriko

2016-02-01

To investigate the lifetime improvement mechanism caused by mixing at the heterojunction interface, organic light-emitting diodes (OLEDs) with stacked and mixed 4,4‧-bis[N-(1-naphthyl)-N-phenyl-amino]-biphenyl (α-NPD)/tris(8-hydroxyquinoline)aluminum (Alq3) interfaces were fabricated, and changes in their displacement current due to continuous operation were measured. A decrease in accumulated holes at the α-NPD/Alq3 interface was observed in the stacked configuration devices over longer operations. These results indicate that the injected hole density was reduced during continuous operation, implying that the carrier balance became uneven in the emission region. However, few accumulated holes and changes in the displacement current due to continuous operation were observed in the devices having the mixed layer. Therefore, it was deduced that the number of holes concentrated between the α-NPD and Alq3 layers was decreased by mixing at the heterojunction interface, and that the change in the number of holes was smaller during continuous operation, resulting in less degradation.

LANMAS core: Update and current directions

International Nuclear Information System (INIS)

Claborn, J.

1994-01-01

Local Area Network Material Accountability System (LANMAS) core software will provide the framework of a material accountability system. LANMAS is a network-based nuclear material accountability system. It tracks the movement of material throughout a site and generates the required reports on material accountability. LANMAS will run in a client/server mode. The database of material type and location will reside on the server, while the user interface runs on the client. The user interface accesses the server via a network. The LANMAS core can be used as the foundation for building required Materials Control and Accountability (MC ampersand A) functionality at any site requiring a new MC ampersand A system. An individual site will build on the LANMAS core by supplying site-specific software. This paper will provide an update on the current LANMAS development activities and discuss the current direction of the LANMAS project

Independent modelling in SSM's licensing review of a spent nuclear fuel repository

International Nuclear Information System (INIS)

Xu, Shulan; Dverstorp, Bjoern; Norden, Maria

2014-01-01

In 2011 the Swedish Nuclear Fuel and Waste Management Co. (SKB) submitted a license application for construction of a geological repository for spent nuclear fuel at Forsmark. SKB's disposal method, the KBS-3 method, involves disposing of the spent nuclear fuel in cast iron canisters with an outer layer of 5 cm copper. The canisters will be placed in vertical deposition holes at approximately 500 m depths in crystalline bedrock. Each canister is surrounded by a buffer of swelling bentonite clay. The repository is designed to accommodate 6 000 canisters, corresponding to 12 000 tonnes of spent nuclear fuel. The license application is supported by a post-closure safety assessment, SR-Site. Along with other parts of the application, SR-Site is currently being reviewed by the Swedish Radiation Safety Authority (SSM). The main method for review of SKB's licensing documentation is document review carried out by SSM, supported by SSM's external experts. However, SSM's document review is also supported by regulatory modelling, technical reviews of SKB's quality assurance programme and consideration of external review comments partly from two broad national consultations and an international peer review organised by the OECD's Nuclear Energy Agency (NEA, 2012). SSM's review is divided into three main phases: the initial review phase, the main review phase and the reporting phase. The overall goal of the initial review phase is to achieve a broad coverage of SR-Site and its supporting references and in particular to identify the need for complementary information and clarifications to be provided by SKB, as well as to identify critical review issues that require a more comprehensive treatment in the main review phase. SSM completed the initial review phase at the end of 2012. During the initial review phase SSM has identified a number of issues requiring either clarifications, complementary information from SKB or further in-depth review by SSM. Important issues include the

Neurobionics and the brain-computer interface: current applications and future horizons.

Science.gov (United States)

Rosenfeld, Jeffrey V; Wong, Yan Tat

2017-05-01

The brain-computer interface (BCI) is an exciting advance in neuroscience and engineering. In a motor BCI, electrical recordings from the motor cortex of paralysed humans are decoded by a computer and used to drive robotic arms or to restore movement in a paralysed hand by stimulating the muscles in the forearm. Simultaneously integrating a BCI with the sensory cortex will further enhance dexterity and fine control. BCIs are also being developed to: provide ambulation for paraplegic patients through controlling robotic exoskeletons; restore vision in people with acquired blindness; detect and control epileptic seizures; and improve control of movement disorders and memory enhancement. High-fidelity connectivity with small groups of neurons requires microelectrode placement in the cerebral cortex. Electrodes placed on the cortical surface are less invasive but produce inferior fidelity. Scalp surface recording using electroencephalography is much less precise. BCI technology is still in an early phase of development and awaits further technical improvements and larger multicentre clinical trials before wider clinical application and impact on the care of people with disabilities. There are also many ethical challenges to explore as this technology evolves.

Universal computer interfaces

CERN Document Server

Dheere, RFBM

1988-01-01

Presents a survey of the latest developments in the field of the universal computer interface, resulting from a study of the world patent literature. Illustrating the state of the art today, the book ranges from basic interface structure, through parameters and common characteristics, to the most important industrial bus realizations. Recent technical enhancements are also included, with special emphasis devoted to the universal interface adapter circuit. Comprehensively indexed.

An improved method for calculation of interface pressure force in PLIC-VOF methods

International Nuclear Information System (INIS)

Sefollahi, M.; Shirani, E.

2004-08-01

Conventional methods for the modeling of surface tension force in Piecewise Linear Interface Calculation-Volume of Fluid (PLIC-VOF) methods, such as Continuum Surface Force (CSF), Continuum Surface Stress (CSS) and also Meier's method, convert the surface tension force into a body force. Not only do they include the force in the interfacial cells but also in the neighboring cells. Thus they produce spurious currents. Also the pressure jump, due to the surface tension, is not calculated accurately in these methods. In this paper a more accurate method for the application of interface force in the computational modeling of free surfaces and interfaces which use PLIC-VOF methods is developed. This method is based on the evaluation of the surface tension force only in the interfacial cells and not the neighboring cells. Also the normal and the interface surface area needed for the calculation of the surface tension force is calculated more accurately. The present method is applied to a two-dimensional motionless drop of liquid and a bubble of gas as well as a non-circular two-dimensional drop, which oscillates due to the surface tension force, in an initially stagnant fluid with no gravity force. The results are compared with the results of the cases when CSF, CSS and Meier's methods are used. It is shown that the present method calculates pressure jump at the interface more accurately and produces less spurious currents comparing to CSS an CSF models. (author)

Interface Input/Output Automata

DEFF Research Database (Denmark)

Larsen, Kim Guldstrand; Nyman, Ulrik; Wasowski, Andrzej

2006-01-01

Building on the theory of interface automata by de Alfaro and Henzinger we design an interface language for Lynch’s I/O, a popular formalism used in the development of distributed asynchronous systems, not addressed by previous interface research. We introduce an explicit separation of assumptions...... a method for solving systems of relativized behavioral inequalities as used in our setup and draw a formal correspondence between our work and interface automata....

Universal quantum interfaces

International Nuclear Information System (INIS)

Lloyd, Seth; Landahl, Andrew J.; Slotine, Jean-Jacques E.

2004-01-01

To observe or control a quantum system, one must interact with it via an interface. This article exhibits simple universal quantum interfaces--quantum input/output ports consisting of a single two-state system or quantum bit that interacts with the system to be observed or controlled. It is shown that under very general conditions the ability to observe and control the quantum bit on its own implies the ability to observe and control the system itself. The interface can also be used as a quantum communication channel, and multiple quantum systems can be connected by interfaces to become an efficient universal quantum computer. Experimental realizations are proposed, and implications for controllability, observability, and quantum information processing are explored

Broadband Prosthetic Interfaces: Combining Nerve Transfers and Implantable Multichannel EMG Technology to Decode Spinal Motor Neuron Activity

Directory of Open Access Journals (Sweden)

Konstantin D. Bergmeister

2017-07-01

Full Text Available Modern robotic hands/upper limbs may replace multiple degrees of freedom of extremity function. However, their intuitive use requires a high number of control signals, which current man-machine interfaces do not provide. Here, we discuss a broadband control interface that combines targeted muscle reinnervation, implantable multichannel electromyographic sensors, and advanced decoding to address the increasing capabilities of modern robotic limbs. With targeted muscle reinnervation, nerves that have lost their targets due to an amputation are surgically transferred to residual stump muscles to increase the number of intuitive prosthetic control signals. This surgery re-establishes a nerve-muscle connection that is used for sensing nerve activity with myoelectric interfaces. Moreover, the nerve transfer determines neurophysiological effects, such as muscular hyper-reinnervation and cortical reafferentation that can be exploited by the myoelectric interface. Modern implantable multichannel EMG sensors provide signals from which it is possible to disentangle the behavior of single motor neurons. Recent studies have shown that the neural drive to muscles can be decoded from these signals and thereby the user's intention can be reliably estimated. By combining these concepts in chronic implants and embedded electronics, we believe that it is in principle possible to establish a broadband man-machine interface, with specific applications in prosthesis control. This perspective illustrates this concept, based on combining advanced surgical techniques with recording hardware and processing algorithms. Here we describe the scientific evidence for this concept, current state of investigations, challenges, and alternative approaches to improve current prosthetic interfaces.

Comparative methods to assess harmonic response of nonlinear piezoelectric energy harvesters interfaced with AC and DC circuits

Science.gov (United States)

Lan, Chunbo; Tang, Lihua; Harne, Ryan L.

2018-05-01

Nonlinear piezoelectric energy harvester (PEH) has been widely investigated during the past few years. Among the majority of these researches, a pure resistive load is used to evaluate power output. To power conventional electronics in practical application, the alternating current (AC) generated by nonlinear PEH needs to be transformed into a direct current (DC) and rectifying circuits are required to interface the device and electronic load. This paper aims at exploring the critical influences of AC and DC interface circuits on nonlinear PEH. As a representative nonlinear PEH, we fabricate and evaluate a monostable PEH in terms of generated power and useful operating bandwidth when it is connected to AC and DC interface circuits. Firstly, the harmonic balance analysis and equivalent circuit representation method are utilized to tackle the modeling of nonlinear energy harvesters connected to AC and DC interface circuits. The performances of the monostable PEH connected to these interface circuits are then analyzed and compared, focusing on the influences of the varying load, excitation and electromechanical coupling strength on the nonlinear dynamics, bandwidth and harvested power. Subsequently, the behaviors of the monostable PEH with AC and DC interface circuits are verified by experiment. Results indicate that both AC and DC interface circuits have a peculiar influence on the power peak shifting and operational bandwidth of the monostable PEH, which is quite different from that on the linear PEH.

The relationship between perceived usability of a beautiful interface and of an ugly interface

OpenAIRE

Mohammed, Naitullah; Syed.Mohammed, Mahamood Ur Rahman

2012-01-01

The relationship between the perceived usability of a beautiful interface and of an ugly interface is analyzed in this study. This study correlates the visual aesthetics of the website with perceived usability. This research is performed to know the significance of visual aesthetics on perceived usability. A website is designed with two interfaces. One interface is designed by following design guidelines with respect to usability and the other interface is designed without following guideline...

Children’s information retrieval: beyond examining search strategies and interfaces

NARCIS (Netherlands)

Jochmann-Mannak, Hanna; Huibers, Theo W.C.; Sanders, T.J.M.

2008-01-01

The study of children’s information retrieval is still for the greater part untouched territory. Meanwhile, children can become lost in the digital information world, because they are confronted with search interfaces, both designed by and for adults. Most current research on children’s information

Shortening User Interface Design Iterations through Realtime Visualisation of Design Actions on the Target Device

OpenAIRE

MESKENS, Jan; LUYTEN, Kris; CONINX, Karin

2009-01-01

In current mobile user interface design tools, it is time consuming to export a design to the target device. This makes it hard for designers to iterate over the user interfaces they are creating. We propose Gummy-live, a GUI builder for mobile devices allowing designers to test and observe immediately on the target device each step they take in the GUI builder. This way, designers are stimulated to iteratively test and refine user interface prototypes in order to take the target device charac...

MER SPICE Interface

Science.gov (United States)

Sayfi, Elias

2004-01-01

MER SPICE Interface is a software module for use in conjunction with the Mars Exploration Rover (MER) mission and the SPICE software system of the Navigation and Ancillary Information Facility (NAIF) at NASA's Jet Propulsion Laboratory. (SPICE is used to acquire, record, and disseminate engineering, navigational, and other ancillary data describing circumstances under which data were acquired by spaceborne scientific instruments.) Given a Spacecraft Clock value, MER SPICE Interface extracts MER-specific data from SPICE kernels (essentially, raw data files) and calculates values for Planet Day Number, Local Solar Longitude, Local Solar Elevation, Local Solar Azimuth, and Local Solar Time (UTC). MER SPICE Interface was adapted from a subroutine, denoted m98SpiceIF written by Payam Zamani, that was intended to calculate SPICE values for the Mars Polar Lander. The main difference between MER SPICE Interface and m98SpiceIf is that MER SPICE Interface does not explicitly call CHRONOS, a time-conversion program that is part of a library of utility subprograms within SPICE. Instead, MER SPICE Interface mimics some portions of the CHRONOS code, the advantage being that it executes much faster and can efficiently be called from a pipeline of events in a parallel processing environment.

Interface Control Document Between the Double-Shell Tank (DST) system and the Waste Encapsulation and Storage Facility (WESF)

International Nuclear Information System (INIS)

HOFFERBER, G.A.

2000-01-01

This Interface Control Document (ICD) describes interfaces between the Double-Shell Tanks (DST) System and Waste Encapsulation and Storage Facility (WESF) (figure 1). WESF is currently operational as a storage facility for cesium and strontium capsules. This ICD covers current operational interfaces and those envisioned during Terminal Clean Out (TCO) activities in the future. WESF and the DST System do not have a direct physical interface. The waste will be moved by tank trailer to the 204-AR waste unloading facility. The purpose of the ICD process is to formalize working agreements between the River Protection Project (RPP) DST System and systems/facilities operated by organizations or companies internal and external to RPP. This ICD has been developed as part of the requirements basis for design of the DST System to support the Phase I Privatization effort

Human-machine interface upgrade

International Nuclear Information System (INIS)

Kropik, M.; Matejka, K.; Sklenka, L.; Chab, V.

2002-01-01

The article describes a new human-machine interface that was installed at the VR-1 training reactor. The human-machine interface upgrade was completed in the summer 2001. The interface was designed with respect to functional, ergonomic and aesthetic requirements. The interface is based on a personal computer equipped with two displays. One display enables alphanumeric communication between the reactor operator and the nuclear reactor I and C. The second display is a graphical one. It presents the status of the reactor, principal parameters (as power, period), control rods positions, course of the reactor power. Furthermore, it is possible to set parameters, to show the active core configuration, to perform reactivity calculations, etc. The software for the new human-machine interface was produced with the InTouch developing tool of the Wonder-Ware Company. It is possible to switch the language of the interface between Czech and English because of many foreign students and visitors to the reactor. Microcomputer based communication units with proper software were developed to connect the new human-machine interface with the present reactor I and C. The new human-machine interface at the VR-1 training reactor improves the comfort and safety of the reactor utilisation, facilitates experiments and training, and provides better support for foreign visitors. (orig.)

Reinforcement steel corrosion in passive state and by carbonation: Consideration of galvanic currents and interface steel - concrete defaults

International Nuclear Information System (INIS)

Nasser, A.

2010-01-01

This thesis aims to study the durability of nuclear waste deep storage structures. The work carried out is essentially an experimental study, and focuses on the corrosion of steel in the passive state with aerated or non-aerated conditions on the one hand, and the corrosion of steel in carbonated concrete during the propagation phase on the other hand. Indeed, the pore solution of concrete in contact with the metal is alkaline (pH between 12 and 13). Under these conditions, steel reinforced concrete remains passive by forming a stable and protective oxide layer (corrosion of steel in the passive state). This passive layer limits the steel corrosion rate at very low values (negligible on a short life time) but not null. For the nuclear waste storage structures due to a very long life time (up to several hundred years), this low corrosion rate can become a risk. Therefore, it is necessary to study the evolution of the oxide layer growth over time. The objectives of the thesis are to study the influence of the steel-concrete interface quality on reinforcement corrosion in passive and active state, and the possible occurrence of galvanic corrosion currents between different reinforcement steel areas. (author)

A bidirectional soft switched ultracapacitor interface circuit for hybrid electric vehicles

Energy Technology Data Exchange (ETDEWEB)

Farzanehfard, Hosein; Beyragh, Dawood Shekari; Adib, Ehsan [Electrical and Computer Engineering Department, Isfahan University of Technology, Isfahan 84156 (Iran)

2008-12-15

Ultracapacitors are used as auxiliary elements beside batteries to increase peak power capability and battery life in hybrid electric vehicles. In such a configuration, a bidirectional high efficiency converter is required as an interface between ultracapacitors and batteries. Since the voltage level of ultracapacitors and batteries are different, the interface must be able to increase or decrease the voltage level in each power flow direction while limiting the current. This paper presents a zero voltage transition (ZVT) buck-and-boost converter for ultracapacitors interface. All the switches in the proposed converter are soft switched to reduce switching losses and increase efficiency. The converter operational modes are analyzed and its performance is discussed. Finally, the experimental results from a 150 W laboratory prototype are presented which justify the theoretical analysis. (author)

Numerical Simulation of Multiphase Magnetohydrodynamic Flow and Deformation of Electrolyte-Metal Interface in Aluminum Electrolysis Cells

Science.gov (United States)

Hua, Jinsong; Rudshaug, Magne; Droste, Christian; Jorgensen, Robert; Giskeodegard, Nils-Haavard

2018-06-01

A computational fluid dynamics based multiphase magnetohydrodynamic (MHD) flow model for simulating the melt flow and bath-metal interface deformation in realistic aluminum reduction cells is presented. The model accounts for the complex physics of the MHD problem in aluminum reduction cells by coupling two immiscible fluids, electromagnetic field, Lorentz force, flow turbulence, and complex cell geometry with large length scale. Especially, the deformation of bath-metal interface is tracked directly in the simulation, and the condition of constant anode-cathode distance (ACD) is maintained by moving anode bottom dynamically with the deforming bath-metal interface. The metal pad deformation and melt flow predicted by the current model are compared to the predictions using a simplified model where the bath-metal interface is assumed flat. The effects of the induced electric current due to fluid flow and the magnetic field due to the interior cell current on the metal pad deformation and melt flow are investigated. The presented model extends the conventional simplified box model by including detailed cell geometry such as the ledge profile and all channels (side, central, and cross-channels). The simulations show the model sensitivity to different side ledge profiles and the cross-channel width by comparing the predicted melt flow and metal pad heaving. In addition, the model dependencies upon the reduction cell operation conditions such as ACD, current distribution on cathode surface and open/closed channel top, are discussed.

The interaction of bubbles with solidification interfaces. [during coasting phase of sounding rocket flight

Science.gov (United States)

Papazian, J. M.; Wilcox, W. R.

1977-01-01

The behavior of bubbles at a dendritic solidification interface was studied during the coasting phase of a sounding rocket flight. Sequential photographs of the gradient freeze experiment showed nucleation, growth and coalescence of bubbles at the moving interface during both the low-gravity and one-gravity tests. In the one-gravity test the bubbles were observed to detach from the interface and float to the top of the melt. However, in the low-gravity tests no bubble detachment from the interface or steady state bubble motion occurred and large voids were grown into the crystal. These observations are discussed in terms of the current theory of thermal migration of bubbles and in terms of their implications on the space processing of metals.

HYDRASTAR - a code for stochastic simulation of groundwater flow

International Nuclear Information System (INIS)

Norman, S.

1992-05-01

The computer code HYDRASTAR was developed as a tool for groundwater flow and transport simulations in the SKB 91 safety analysis project. Its conceptual ideas can be traced back to a report by Shlomo Neuman in 1988, see the reference section. The main idea of the code is the treatment of the rock as a stochastic continuum which separates it from the deterministic methods previously employed by SKB and also from the discrete fracture models. The current report is a comprehensive description of HYDRASTAR including such topics as regularization or upscaling of a hydraulic conductivity field, unconditional and conditional simulation of stochastic processes, numerical solvers for the hydrology and streamline equations and finally some proposals for future developments

Migration of the ATLAS Metadata Interface (AMI) to Web 2.0 and cloud

Science.gov (United States)

Odier, J.; Albrand, S.; Fulachier, J.; Lambert, F.

2015-12-01

The ATLAS Metadata Interface (AMI), a mature application of more than 10 years of existence, is currently under adaptation to some recently available technologies. The web interfaces, which previously manipulated XML documents using XSL transformations, are being migrated to Asynchronous JavaScript (AJAX). Web development is considerably simplified by the introduction of a framework based on JQuery and Twitter Bootstrap. Finally, the AMI services are being migrated to an OpenStack cloud infrastructure.

Aespoe Hard Rock Laboratory. Status Report. September - December 2010

Energy Technology Data Exchange (ETDEWEB)

2011-04-15

The Aespoe Hard Rock Laboratory (HRL) constitutes an important part of SKB's work to design and construct a geological repository for spent nuclear fuel and to develop and test methods for characterisation of a suitable site. In September 2010, the plans for SKB's research and development of technique during the period 2011-2016 were presented in SKB's RDandD-Programme 2010 /SKB 2010a/. The information given in the RDandD-Programme related to Aespoe HRL is annually detailed in the Aespoe HRL Planning Report and the information valid for 2010 is given in /SKB 2010b/. This Aespoe HRL Status Report is a collection of the main achievements obtained during the period September to December 2010

Solar wind stream interfaces

International Nuclear Information System (INIS)

Gosling, J.T.; Asbridge, J.R.; Bame, S.J.; Feldman, W.C.

1978-01-01

Measurements aboard Imp 6, 7, and 8 reveal that approximately one third of all high-speed solar wind streams observed at 1 AU contain a sharp boundary (of thickness less than approx.4 x 10 4 km) near their leading edge, called a stream interface, which separates plasma of distinctly different properties and origins. Identified as discontinuities across which the density drops abruptly, the proton temperature increases abruptly, and the speed rises, stream interfaces are remarkably similar in character from one stream to the next. A superposed epoch analysis of plasma data has been performed for 23 discontinuous stream interfaces observed during the interval March 1971 through August 1974. Among the results of this analysis are the following: (1) a stream interface separates what was originally thick (i.e., dense) slow gas from what was originally thin (i.e., rare) fast gas; (2) the interface is the site of a discontinuous shear in the solar wind flow in a frame of reference corotating with the sun; (3) stream interfaces occur at speeds less than 450 km s - 1 and close to or at the maximum of the pressure ridge at the leading edges of high-speed streams; (4) a discontinuous rise by approx.40% in electron temperature occurs at the interface; and (5) discontinuous changes (usually rises) in alpha particle abundance and flow speed relative to the protons occur at the interface. Stream interfaces do not generally recur on successive solar rotations, even though the streams in which they are embedded often do. At distances beyond several astronomical units, stream interfaces should be bounded by forward-reverse shock pairs; three of four reverse shocks observed at 1 AU during 1971--1974 were preceded within approx.1 day by stream interfaces. Our observations suggest that many streams close to the sun are bounded on all sides by large radial velocity shears separating rapidly expanding plasma from more slowly expanding plasma

Microcomputer interfacing and applications

CERN Document Server

Mustafa, M A

1990-01-01

This is the applications guide to interfacing microcomputers. It offers practical non-mathematical solutions to interfacing problems in many applications including data acquisition and control. Emphasis is given to the definition of the objectives of the interface, then comparing possible solutions and producing the best interface for every situation. Dr Mustafa A Mustafa is a senior designer of control equipment and has written many technical articles and papers on the subject of computers and their application to control engineering.

Towards emotion modeling based on gaze dynamics in generic interfaces

DEFF Research Database (Denmark)

Vester-Christensen, Martin; Leimberg, Denis; Ersbøll, Bjarne Kjær

2005-01-01

Gaze detection can be a useful ingredient in generic human computer interfaces if current technical barriers are overcome. We discuss the feasibility of concurrent posture and eye-tracking in the context of single (low cost) camera imagery. The ingredients in the approach are posture and eye region...

Plane-Wave Characterization of Antennas Close to a Planar Interface

DEFF Research Database (Denmark)

Meincke, Peter; Hansen, Thorkild

2004-01-01

The plane-wave scattering matrix is used to characterize antennas that are located just above a planar interface that separates two media. The plane-wave transmitting spectrum for the field radiated downwards into the lower medium is expressed directly in terms of the current distribution of the ...

Electron drag in ferromagnetic structures separated by an insulating interface

Science.gov (United States)

Kozub, V. I.; Muradov, M. I.; Galperin, Y. M.

2018-06-01

We consider electron drag in a system of two ferromagnetic layers separated by an insulating interface. The source of it is expected to be magnon-electron interactions. Namely, we assume that the external voltage is applied to the "active" layer stimulating electric current through this layer. In its turn, the scattering of the current-carrying electrons by magnons leads to a magnon drag current within this layer. The 3-magnons interactions between magnons in the two layers (being of non-local nature) lead to magnon drag within the "passive" layer which, correspondingly, produce electron drag current via processes of magnon-electron scattering. We estimate the drag current and compare it to the phonon-induced one.

Brain–muscle interface

Indian Academy of Sciences (India)

2011-05-16

May 16, 2011 ... Clipboard: Brain–muscle interface: The next-generation BMI. Radhika Rajan Neeraj Jain ... Keywords. Assistive devices; brain–machine interface; motor cortex; paralysis; spinal cord injury ... Journal of Biosciences | News ...

Design principles of a web interface for monitoring tools

International Nuclear Information System (INIS)

Aiftimiei, C; Pra, S D; Fantinel, S; Andreozzi, S; Fattibene, E; Misurelli, G; Cuscela, G; Donvito, G; Dudhalkar, V; Maggi, G; Pierro, A

2008-01-01

A monitoring tool of a complex Grid system can gather a huge amount of information that have to be presented to the users in the most comprehensive way. Moreover different types of consumers could be interested in inspecting and analyzing different subsets of data. The main goal in designing a Web interface for the presentation of monitoring information is to organize the huge amount of data in a simple, user-friendly and usable structure. One more problem is to consider different approaches, skills and interests that all the possible categories of users have in looking for the desired information. Starting from the Information Architecture guidelines for the Web, it is possible to design Web interfaces towards a closer user experience and to deal with an advanced user interaction through the implementation of many Web standard technologies. In this paper, we will present a number of principles for the design of Web interface for monitoring tools that provide a wider, richer range of possibilities for what concerns the user interaction. These principles are based on an extensive review of the current literature in Web design and on the experience with the development of the GridICE monitoring tool. The described principles can drive the evolution of the Web interface of Grid monitoring tools

Improvement to the signaling interface for CMOS pixel sensors

Energy Technology Data Exchange (ETDEWEB)

Shi, Zhan, E-mail: sz1134@163.com [Dalian University of Technology, No.2 Linggong Road, 116024 Dalian (China); Tang, Zhenan, E-mail: tangza@dlut.edu.cn [Dalian University of Technology, No.2 Linggong Road, 116024 Dalian (China); Feng, Chong [Dalian University of Technology, No.2 Linggong Road, 116024 Dalian (China); Dalian Minzu University, No.18 Liaohe West Road, 116600 Dalian (China); Cai, Hong [Dalian University of Technology, No.2 Linggong Road, 116024 Dalian (China)

2016-10-01

The development of the readout speed of CMOS pixel sensors (CPS) is motivated by the demanding requirements of future high energy physics (HEP) experiments. As the interface between CPS and the data acquisition (DAQ) system, which inputs clock from the DAQ system and outputs data from CPS, the signaling interface should also be improved in terms of data rates. Meanwhile, the power consumption of the signaling interface should be maintained as low as possible. Consequently, a reduced swing differential signaling (RSDS) driver was adopted instead of a low-voltage differential signaling (LVDS) driver to transmit data from CPS to the DAQ system. In order to increase the capability of data rates, a serial source termination technique was employed. A LVDS/RSDS receiver was employed for transmitting clock from the DAQ system to CPS. A new method of generating hysteresis and a special current comparator were used to achieve a higher speed with lower power consumption. The signaling interface was designed and submitted for fabrication in a 0.18 µm CMOS image sensor (CIS) process. Measurement results indicate that the RSDS driver and the LVDS receiver can operate correctly at a data rate of 2 Gb/s with a power consumption of 19.1 mW.

Playful user interfaces interfaces that invite social and physical interaction

CERN Document Server

2014-01-01

The book is about user interfaces to applications that have been designed for social and physical interaction. The interfaces are ‘playful’, that is, users feel challenged to engage in social and physical interaction because that will be fun. The topics that will be present in this book are interactive playgrounds, urban games using mobiles, sensor-equipped environments for playing, child-computer interaction, tangible game interfaces, interactive tabletop technology and applications, full-body interaction, exertion games, persuasion, engagement, evaluation, and user experience. Readers of the book will not only get a survey of state-of-the-art research in these areas, but the chapters in this book will also provide a vision of the future where playful interfaces will be ubiquitous, that is, present and integrated in home, office, recreational, sports and urban environments, emphasizing that in the future in these environments game elements will be integrated and welcomed.

Density of interface states, excess capacitance and series resistance in the metal-insulator-semiconductor (MIS) solar cells

Energy Technology Data Exchange (ETDEWEB)

Altindal, Semsettin; Tataroglu, Adem; Dokme, Ilbilge [Faculty of Arts and Sciences, Physics Department, Gazi University, 06500, Ankara (Turkey)

2005-01-31

Dark and illuminated current-voltage (I-V) characteristics of Al/SiO{sub x}/p-Si metal-insulator-semiconductor (MIS) solar cells were measured at room temperature. In addition to capacitance-voltage (C-V) and conductance-voltage (G-V), characteristics are studied at a wide frequency range of 1kHz-10MHz. The dark I-V characteristics showed non-ideal behavior with an ideal factor of 3.2. The density of interface states distribution profiles as a function of (E{sub ss}-E{sub v}) deduced from the I-V measurements at room temperature for the MIS solar cells on the order of 10{sup 13}cm{sup -2}eV{sup -1}. These interface states were responsible for the non-ideal behavior of I-V, C-V and G-V characteristics. Frequency dispersion in capacitance for MIS solar cells can be interpreted only in terms of interface states. The interface states can follow the a.c. signal and yield an excess capacitance, which depends on the relaxation time of interface states and the frequency of the a.c. signal. It was observed that the excess capacitance C{sub o} caused by an interface state decreases with an increase of frequency. The capacitances characteristics of MIS solar cells are affected not only in interface states but also series resistance. Analysis of this data indicated that the high interface states and series resistance leads to lower values of open-circuit voltage, short-circuit current density, and fill factor. Experimental results show that the location of interface states and series resistance have a significant effect on I-V, C-V and G-V characteristics.

Perspective of next generation training system from the viewpoints of human interfaces. Human interface kara mita kyoiku kunren system no genjo to kongo no tenbo

Energy Technology Data Exchange (ETDEWEB)

Nishida, S [Mitsubishi Electric Corp., Tokyo (Japan)

1992-12-10

This paper describes an education and training system placing its emphasis on human interfaces. The paper indicates that the currently used education and training systems lack training functions to cultivate knowledge-based judgment abilities that can find adequate solutions to events that have not been experienced previously; such judgments require deep understanding on the objects; and this training requires a system to aid the comprehension based on knowledges in the realm of recognition science for the 'human understanding'. Next, a pedagogical interface is proposed for aiding the comprehension. The paper enumerates functions indispensable for the comprehension including setting the 'loop for representation and examination', aiding the representation to examination loop, aiding roles by others, and realizing interactions through a hypothetical world. Also enumerated as fundamental techniques to structure such interface are information structuring techniques, groupware techniques, and virtual reality techniques. 19 refs., 10 figs.

Lectures on random interfaces

CERN Document Server

Funaki, Tadahisa

2016-01-01

Interfaces are created to separate two distinct phases in a situation in which phase coexistence occurs. This book discusses randomly fluctuating interfaces in several different settings and from several points of view: discrete/continuum, microscopic/macroscopic, and static/dynamic theories. The following four topics in particular are dealt with in the book. Assuming that the interface is represented as a height function measured from a fixed-reference discretized hyperplane, the system is governed by the Hamiltonian of gradient of the height functions. This is a kind of effective interface model called ∇φ-interface model. The scaling limits are studied for Gaussian (or non-Gaussian) random fields with a pinning effect under a situation in which the rate functional of the corresponding large deviation principle has non-unique minimizers. Young diagrams determine decreasing interfaces, and their dynamics are introduced. The large-scale behavior of such dynamics is studied from the points of view of the hyd...

Heterojunction interface double layer and consequences for photovoltaic cells, specifically Cdsub(z)Znsub(1-z)S/Cu2S

International Nuclear Information System (INIS)

Boeer, K.W.

1978-01-01

It is shown that an interface dislocation field at a heterojunction with substantial lattice mismatch needs charge compensation which can cause a double layer producing a potential spike at the interface. Tunneling through such a spike reduces the current through the interface. Reasonable agreement between theory and experiment is obtained for Cdsub(z)Znsub(1-z)S/Cu 2 S photovoltaic cells. (author)

Configuring a Graphical User Interface for Managing Local HYSPLIT Model Runs Through AWIPS

Science.gov (United States)

Wheeler, mark M.; Blottman, Peter F.; Sharp, David W.; Hoeth, Brian; VanSpeybroeck, Kurt M.

2009-01-01

Responding to incidents involving the release of harmful airborne pollutants is a continual challenge for Weather Forecast Offices in the National Weather Service. When such incidents occur, current protocol recommends forecaster-initiated requests of NOAA's Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) model output through the National Centers of Environmental Prediction to obtain critical dispersion guidance. Individual requests are submitted manually through a secured web site, with desired multiple requests submitted in sequence, for the purpose of obtaining useful trajectory and concentration forecasts associated with the significant release of harmful chemical gases, radiation, wildfire smoke, etc., into local the atmosphere. To help manage the local HYSPLIT for both routine and emergency use, a graphical user interface was designed for operational efficiency. The interface allows forecasters to quickly determine the current HYSPLIT configuration for the list of predefined sites (e.g., fixed sites and floating sites), and to make any necessary adjustments to key parameters such as Input Model. Number of Forecast Hours, etc. When using the interface, forecasters will obtain desired output more confidently and without the danger of corrupting essential configuration files.

Exploring 'new' bioactivities of polymers at the nano-bio interface.

Science.gov (United States)

Wang, Chunming; Dong, Lei

2015-01-01

A biological system is essentially an elegant assembly of polymeric nanostructures. The polymers in the body, biomacromolecules, are both building blocks and versatile messengers. We propose that non-biologically derived polymers can be potential therapeutic candidates with unique advantages. Emerging findings about polycations, polysaccharides, immobilised multivalent ligands, and biomolecular coronas provide evidence that polymers are activated at the nano-bio interface, while emphasising the current theoretical and practical challenges. Our increasing understanding of the nano-bio interface and evolving approaches to establish the therapeutic potential of polymers enable the development of polymer drugs with high specificities for broad applications. Copyright © 2014 Elsevier Ltd. All rights reserved.

Interface States in AlGaN/GaN Metal-Insulator-Semiconductor High Electron Mobility Transistors

International Nuclear Information System (INIS)

Feng Qian; Du Kai; Li Yu-Kun; Shi Peng; Feng Qing

2013-01-01

Frequency-dependent capacitance and conductance measurements are performed on AlGaN/GaN high electron mobility transistors (HEMTs) and NbAlO/AlGaN/GaN metal-insulator-semiconductor HEMTs (MISHEMTs) to extract density and time constants of the trap states at NbAlO/AlGaN interface and gate/AlGaN interface with the gate-voltage biased into the accumulation region and that at the AlGaN/GaN interface with the gate-voltage biased into the depletion region in different circuit models. The measurement results indicate that the trap density at NbAlO/AlGaN interface is about one order lower than that at gate/AlGaN interface while the trap density at AlGaN/GaN interface is in the same order, so the NbAlO film can passivate the AlGaN surface effectively, which is consistent with the current collapse results

X-windows-based user interface for data acquisition and display

International Nuclear Information System (INIS)

Fredian, T.W.; Stillerman, J.A.

1990-01-01

A Macintosh-like user interface for the MDS-Plus data acquisition system is being implemented using the DECwindows MIT/X interface. MDS-Plus is a model driven general purpose data acquisition system being developed collaboratively by the CMOD group at MIT Plasma Fusion Center, the RFX group at IGI-Padua, and the ZTH group at Los Alamos National Laboratory. The model is a hierarchical description of an experiment, including all of the tasks to be performed and the results of having performed them. The inherent complexity of this experimental model requires the users to specify fairly complicated descriptions of what they want the system to do. A ''Point and Click'' interface simplifies this by presenting to the user a coherent set of choices which are valid in the current context. We are implementing a set of tools for data acquisition and data analysis which use DECwindows to this end. They include a data displayer (Scope Replacement), an experiment model editor (Tree Editor), a timing system, and a waveform editor. These tools provide an easy to use interface to the MDS-Plus data acquisition system

Effects of current stressing on the p-Bi2Te3/Sn interfacial reactions

International Nuclear Information System (INIS)

Chan, Hsing-Ting; Lin, Chih-Fan; Yen, Yee-Wen; Chen, Chih-Ming

2016-01-01

The Sn/p-Bi 2 Te 3 /Sn sandwich-type sample was current stressed with a density of 150 A/cm 2 to investigate the effects of current stressing on the p-Bi 2 Te 3 /Sn interfacial reactions. Asymmetrical heating phenomenon was observed at the anodic Sn/p-Bi 2 Te 3 (50 °C) and cathodic p-Bi 2 Te 3 /Sn (120 °C) interfaces due to the Peltier effect. Besides the Peltier effect, the electromigration effect also influenced the growth of the SnTe phase and therefore polarity growth behavior was observed at the two interfaces. The growth of the SnTe phase at the cathodic p-Bi 2 Te 3 /Sn interface was accelerated because Peltier and electromigration effects drove more Sn atoms (dominant diffusion species) for the phase growth. By measuring the electromigration-induced atomic flux of Sn, the product of diffusivity and effective charge number (D × z*) was calculated to be 6.3 × 10 −9 cm 2 s −1 at 120 °C. - Highlights: • Sn/p-Bi 2 Te 3 /Sn sandwich-type sample is current stressed with a density of 150 A/cm 2 . • Passage of an electric current induces Peltier and electromigration effects. • Peltier effect causes asymmetrical heating at the anode and cathode interfaces. • Both effects accelerate the SnTe growth at the cathode interface. • Sn is the dominant diffusion species identified by a marker experiment.

Electrokinetics of diffuse soft interfaces. 1. Limit of low Donnan potentials.

Science.gov (United States)

Duval, Jérôme F L; van Leeuwen, Herman P

2004-11-09

The current theoretical approaches to electrokinetics of gels or polyelectrolyte layers are based on the assumption that the position of the very interface between the aqueous medium and the gel phase is well defined. Within this assumption, spatial profiles for the volume fraction of polymer segments (phi), the density of fixed charges in the porous layer (rho fix), and the coefficient modeling the friction to hydrodynamic flow (k) follow a step-function. In reality, the "fuzzy" nature of the charged soft layer is intrinsically incompatible with the concept of a sharp interface and therefore necessarily calls for more detailed spatial representations for phi, rho fix, and k. In this paper, the notion of diffuse interface is introduced. For the sake of illustration, linear spatial distributions for phi and rho fix are considered in the interfacial zone between the bulk of the porous charged layer and the bulk electrolyte solution. The corresponding distribution for k is inferred from the Brinkman equation, which for low phi reduces to Stokes' equation. Linear electrostatics, hydrodynamics, and electroosmosis issues are analytically solved within the context of streaming current and streaming potential of charged surface layers in a thin-layer cell. The hydrodynamic analysis clearly demonstrates the physical incorrectness of the concept of a discrete slip plane for diffuse interfaces. For moderate to low electrolyte concentrations and nanoscale spatial transition of phi from zero (bulk electrolyte) to phi o (bulk gel), the electrokinetic properties of the soft layer as predicted by the theory considerably deviate from those calculated on the basis of the discontinuous approximation by Ohshima.

Microstructural studies on degradation of interface between LSM–YSZ cathode and YSZ electrolyte in SOFCs

DEFF Research Database (Denmark)

Liu, Yi-Lin; Hagen, Anke; Barfod, Rasmus

2009-01-01

The changes in the cathode/electrolyte interface microstructure have been studied on anode-supported technological solid oxide fuel cells (SOFCs) that were subjected to long-term (1500 h) testing at 750 °C under high electrical loading (a current density of 0.75 A/cm2). These cells exhibit...... different cathode degradation rates depending on, among others, the composition of the cathode gas, being significantly smaller in oxygen than in air. FE-SEM and high resolution analytical TEM were applied for characterization of the interface on a submicron- and nano-scale. The interface degradation has...... to decrease further due to the more pronounced formation of insulating zirconate phases that are present locally and preferably in LSM/YSZ electrolyte contact areas. The effects of the cathode gas on the interface degradation are discussed considering the change of oxygen activity at the interface, possible...

Interface superconductivity

Energy Technology Data Exchange (ETDEWEB)

Gariglio, S., E-mail: stefano.gariglio@unige.ch [DQMP, Université de Genève, 24 Quai E.-Ansermet, CH-1211 Genève (Switzerland); Gabay, M. [Laboratoire de Physique des Solides, Bat 510, Université Paris-Sud 11, Centre d’Orsay, 91405 Orsay Cedex (France); Mannhart, J. [Max Planck Institute for Solid State Research, 70569 Stuttgart (Germany); Triscone, J.-M. [DQMP, Université de Genève, 24 Quai E.-Ansermet, CH-1211 Genève (Switzerland)

2015-07-15

Highlights: • We discuss interfacial superconductivity, a field boosted by the discovery of the superconducting interface between LaAlO. • This system allows the electric field control and the on/off switching of the superconducting state. • We compare superconductivity at the interface and in bulk doped SrTiO. • We discuss the role of the interfacially induced Rashba type spin–orbit. • We briefly discuss superconductivity in cuprates, in electrical double layer transistor field effect experiments. • Recent observations of a high T{sub c} in a monolayer of FeSe deposited on SrTiO{sub 3} are presented. - Abstract: Low dimensional superconducting systems have been the subject of numerous studies for many years. In this article, we focus our attention on interfacial superconductivity, a field that has been boosted by the discovery of superconductivity at the interface between the two band insulators LaAlO{sub 3} and SrTiO{sub 3}. We explore the properties of this amazing system that allows the electric field control and on/off switching of superconductivity. We discuss the similarities and differences between bulk doped SrTiO{sub 3} and the interface system and the possible role of the interfacially induced Rashba type spin–orbit. We also, more briefly, discuss interface superconductivity in cuprates, in electrical double layer transistor field effect experiments, and the recent observation of a high T{sub c} in a monolayer of FeSe deposited on SrTiO{sub 3}.

Magnons and interface magnetic substructures

International Nuclear Information System (INIS)

Djafari-Rouhani, B.; Dobrzynski, L.

1975-01-01

The localized magnons at an interface between two Heisenberg ferromagnets and the ferromagnetic stability at the interface are studied. The authors consider simple cubic crystals having the same lattice parameter and the same spin value in the fundamental state on each site, but different exchange integrals between first and second nearest neighbours. An interface by coupling two semi-infinite crystals having the same crystallographic surface is defined. The conditions for the existence of localized magnons at (001) interfaces as well as the dispersion curves of localized and resonant magnons in the high symmetry directions of the Brillouin zone are studied. The effect of the interface interactions on these modes is determined. It is shown that magnetic superstructures may exist at (110) interfaces. Such an instability is given by the existence of a soft localized mode at the interface [fr

Current-Driven Switch-Mode Audio Power Amplifiers

DEFF Research Database (Denmark)

Knott, Arnold; Buhl, Niels Christian; Andersen, Michael A. E.

2012-01-01

The conversion of electrical energy into sound waves by electromechanical transducers is proportional to the current through the coil of the transducer. However virtually all audio power amplifiers provide a controlled voltage through the interface to the transducer. This paper is presenting...... a switch-mode audio power amplifier not only providing controlled current but also being supplied by current. This results in an output filter size reduction by a factor of 6. The implemented prototype shows decent audio performance with THD + N below 0.1 %....

An Interface Transformation Strategy for AF-IPPS

Science.gov (United States)

2012-12-01

Oracle, or SAP . Like other AF and Department of Defense (DoD) ERP programs, AF-IPPS is expected to have 100+ interfaces with 90+ external trading partners...platform such as PeopleSoft, Oracle, or SAP . Like other AF and Department of Defense (DoD) ERP programs, AF-IPPS is expected to have 100...currently perform these functions. The core of AF-IPPS will be implemented using an Enterprise Resource Planning ( ERP ) platform such as PeopleSoft

The interface effect

CERN Document Server

Galloway, Alexander R

2013-01-01

Interfaces are back, or perhaps they never left. The familiar Socratic conceit from the Phaedrus, of communication as the process of writing directly on the soul of the other, has returned to center stage in today's discussions of culture and media. Indeed Western thought has long construed media as a grand choice between two kinds of interfaces. Following the optimistic path, media seamlessly interface self and other in a transparent and immediate connection. But, following the pessimistic path, media are the obstacles to direct communion, disintegrating self and other into misunderstanding

Graphical Interfaces for Simulation.

Science.gov (United States)

Hollan, J. D.; And Others

This document presents a discussion of the development of a set of software tools to assist in the construction of interfaces to simulations and real-time systems. Presuppositions to the approach to interface design that was used are surveyed, the tools are described, and the conclusions drawn from these experiences in graphical interface design…

TacTool: a tactile rapid prototyping tool for visual interfaces

NARCIS (Netherlands)

Keyson, D.V.; Tang, H.K.; Anzai, Y.; Ogawa, K.; Mori, H.

1995-01-01

This paper describes the TacTool development tool and input device for designing and evaluating visual user interfaces with tactile feedback. TacTool is currently supported by the IPO trackball with force feedback in the x and y directions. The tool is designed to enable both the designer and the

Advanced operator interface design for CANDU-3 fuel handling system

Energy Technology Data Exchange (ETDEWEB)

Arapakota, D [Atomic Energy of Canada Ltd., Saskatoon, SK (Canada)

1996-12-31

The Operator Interface for the CANDU 3 Fuel Handling (F/H) System incorporates several improvements over the existing designs. A functionally independent sit-down CRT (cathode-ray tube) based Control Console is provided for the Fuel Handling Operator in the Main Control Room. The Display System makes use of current technology and provides a user friendly operator interface. Regular and emergency control operations can be carried out from this control console. A stand-up control panel is provided as a back-up with limited functionality adequate to put the F/H System in a safe state in case of an unlikely non-availability of the Plant Display System or the F/H Control System`. The system design philosophy, hardware configuration and the advanced display system features are described in this paper The F/H Operator Interface System developed for CANDU 3 can be adapted to CANDU 9 as well as to the existing stations. (author).

Advanced operator interface design for CANDU-3 fuel handling system

International Nuclear Information System (INIS)

Arapakota, D.

1995-01-01

The Operator Interface for the CANDU 3 Fuel Handling (F/H) System incorporates several improvements over the existing designs. A functionally independent sit-down CRT (cathode-ray tube) based Control Console is provided for the Fuel Handling Operator in the Main Control Room. The Display System makes use of current technology and provides a user friendly operator interface. Regular and emergency control operations can be carried out from this control console. A stand-up control panel is provided as a back-up with limited functionality adequate to put the F/H System in a safe state in case of an unlikely non-availability of the Plant Display System or the F/H Control System'. The system design philosophy, hardware configuration and the advanced display system features are described in this paper The F/H Operator Interface System developed for CANDU 3 can be adapted to CANDU 9 as well as to the existing stations. (author)

Comparative analysis of safety related site characteristics

International Nuclear Information System (INIS)

Andersson, Johan

2010-12-01

This document presents a comparative analysis of site characteristics related to long-term safety for the two candidate sites for a final repository for spent nuclear fuel in Forsmark (municipality of Oesthammar) and in Laxemar (municipality of Oskarshamn) from the point of view of site selection. The analyses are based on the updated site descriptions of Forsmark /SKB 2008a/ and Laxemar /SKB 2009a/, together with associated updated repository layouts and designs /SKB 2008b and SKB 2009b/. The basis for the comparison is thus two equally and thoroughly assessed sites. However, the analyses presented here are focussed on differences between the sites rather than evaluating them in absolute terms. The document serves as a basis for the site selection, from the perspective of long-term safety, in SKB's application for a final repository. A full evaluation of safety is made for a repository at the selected site in the safety assessment SR-Site /SKB 2011/, referred to as SR-Site main report in the following

Comparative analysis of safety related site characteristics

Energy Technology Data Exchange (ETDEWEB)

Andersson, Johan (ed.)

2010-12-15

This document presents a comparative analysis of site characteristics related to long-term safety for the two candidate sites for a final repository for spent nuclear fuel in Forsmark (municipality of Oesthammar) and in Laxemar (municipality of Oskarshamn) from the point of view of site selection. The analyses are based on the updated site descriptions of Forsmark /SKB 2008a/ and Laxemar /SKB 2009a/, together with associated updated repository layouts and designs /SKB 2008b and SKB 2009b/. The basis for the comparison is thus two equally and thoroughly assessed sites. However, the analyses presented here are focussed on differences between the sites rather than evaluating them in absolute terms. The document serves as a basis for the site selection, from the perspective of long-term safety, in SKB's application for a final repository. A full evaluation of safety is made for a repository at the selected site in the safety assessment SR-Site /SKB 2011/, referred to as SR-Site main report in the following

Knowledge-based critiquing of graphical user interfaces with CHIMES

Science.gov (United States)

Jiang, Jianping; Murphy, Elizabeth D.; Carter, Leslie E.; Truszkowski, Walter F.

1994-01-01

CHIMES is a critiquing tool that automates the process of checking graphical user interface (GUI) designs for compliance with human factors design guidelines and toolkit style guides. The current prototype identifies instances of non-compliance and presents problem statements, advice, and tips to the GUI designer. Changes requested by the designer are made automatically, and the revised GUI is re-evaluated. A case study conducted at NASA-Goddard showed that CHIMES has the potential for dramatically reducing the time formerly spent in hands-on consistency checking. Capabilities recently added to CHIMES include exception handling and rule building. CHIMES is intended for use prior to usability testing as a means, for example, of catching and correcting syntactic inconsistencies in a larger user interface.

Theory of the Spin Galvanic Effect at Oxide Interfaces

Science.gov (United States)

Seibold, Götz; Caprara, Sergio; Grilli, Marco; Raimondi, Roberto

2017-12-01

The spin galvanic effect (SGE) describes the conversion of a nonequilibrium spin polarization into a transverse charge current. Recent experiments have demonstrated a large conversion efficiency for the two-dimensional electron gas formed at the interface between two insulating oxides, LaAlO3 and SrTiO3 . Here, we analyze the SGE for oxide interfaces within a three-band model for the Ti t2 g orbitals which displays an interesting variety of effective spin-orbit couplings in the individual bands that contribute differently to the spin-charge conversion. Our analytical approach is supplemented by a numerical treatment where we also investigate the influence of disorder and temperature, which turns out to be crucial to providing an appropriate description of the experimental data.

Playful User Interfaces. Interfaces that Invite Social and Physical Interaction.

NARCIS (Netherlands)

Nijholt, Antinus; Unknown, [Unknown

2014-01-01

This book is about user interfaces to applications that can be considered as ‘playful’. The interfaces to such applications should be ‘playful’ as well. The application should be fun, and interacting with such an application should, of course, be fun as well. Maybe more. Why not expect that the

Electrochemical detection of dopamine using arrays of liquid-liquid micro-interfaces created within micromachined silicon membranes

International Nuclear Information System (INIS)

Berduque, Alfonso; Zazpe, Raul; Arrigan, Damien W.M.

2008-01-01

The detection of protonated dopamine by differential pulse voltammetry (DPV) and square wave voltammetry (SWV) at arrays of micro-interfaces between two immiscible electrolyte solutions (μITIES) is presented. Microfabricated porous silicon membranes (consisting of eight pores, 26.6 μm in radius and 500 μm pore-pore separation, in a hexagonal layout) were prepared by photolithographic and etching procedures. The membrane pores were fabricated with hydrophobic internal walls so that the organic phase filled the pores and created the liquid interface at the aqueous side of the membrane. These were used for harnessing the benefits of three-dimensional diffusion to the interface and for interface stabilisation. The liquid-liquid interface provides a simple method to overcome the major problem in the voltammetric detection of dopamine at solid electrodes due to the co-existence of ascorbate at higher concentrations. Selectivity for dopamine over ascorbate was achieved by the use of dibenzo-18-crown-6 (DB18C6) for the facilitated ion transfer of dopamine across the μITIES array. Under these conditions, the presence of ascorbate in excess did not interfere in the detection of dopamine and the lowest concentration detectable was ca. 0.5 μM. In addition, the drawback of current signal saturation (non-linear increase of the peak current with the concentration of dopamine) observed at conventional (millimetre-sized) liquid-liquid interfaces was overcome using the microfabricated porous membranes

Interfacing Sensors To Micro Controllers

KAUST Repository

Norain, Mohamed

2018-01-01

This lecture will cover the most common interface and interface techniques between sensors and microcontrollers. The presentation will introduce the pros and cons of each interface type including analogue, digital and serial output sensors. It will also cover the basic required electronics knowledge to help you in selecting and designing your next sensor to microcontroller interface.