| 1. |
- Ahrens, J, et al.
(author)
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Helicity dependence of the (gamma)over-right-arrow (p)over-right-arrow -> n pi(+) pi(0) reaction in the second resonance region
- 2003
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In: Physics Letters. Section B: Nuclear, Elementary Particle and High-Energy Physics. - 0370-2693. ; 551:1-2, s. 49-55
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Journal article (peer-reviewed)abstract
- The helicity dependence of the total cross section for the (γ) over right arrow(p) over right arrownpi(+) pi(0) reaction has been measured for the first time at incident photon energies from 400 to 800 MeV The measurement was performed with the large acceptance detector DAPHNE at the tagged photon beam facility of the MAMI accelerator in Mainz. This channel is found to be excited predominantly when the photon and proton have a parallel spin orientation, due to the intermediate production of the D-13 resonance. (C) 2002 Elsevier Science B.V. All rights reserved.
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| 2. |
- Ahrens, J, et al.
(author)
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First measurement of the helicity-dependent (gamma)over-right-arrow(p)over-right-arrow -> p eta differential cross-section
- 2003
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In: European Physical Journal A. Hadrons and Nuclei. - : Springer Science and Business Media LLC. - 1434-6001. ; 17:2, s. 241-244
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Journal article (peer-reviewed)abstract
- The helicity dependence of the (γ) over right arrow(p) over right arrow -+ peta reaction has been measured for the first time at a center-of-mass angle theta(eta)*= 70degrees in the photon energy range from 780 MeV to 790 MeV. The experiment, performed at the Mainz microtron MAMI, used a 4pi-detector system, a circularly polarized, tagged photon beam. and a longitudinally polarized frozen-spin target. The helicity 3/2 cross-section is found to be small and the results for helicity 1/2 agree with predictions from the MAID analysis.
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| 3. |
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| 4. |
- Ahrens, J, et al.
(author)
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Helicity dependence of the gamma p -> N pi channels and multipole analysis in the Delta region
- 2004
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In: European Physical Journal A. Hadrons and Nuclei. - : Springer Science and Business Media LLC. - 1434-6001. ; 21:2, s. 323-333
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Journal article (peer-reviewed)abstract
- A high-quality double-polarization data set for the helicity dependence of the total and differential cross-sections for both gammap --> Npi channels in the Delta region has been obtained in the framework of the GDH experiment. The experiment, performed at the Mainz microtron MAMI, used a 4pi detection system, a circularly polarized photon beam, and a longitudinally polarized frozen-spin target. These data are included in the database to perform a multipole analysis to determine the properties of the Delta(1232)-resonance. For the resonant Delta(1232) multipoles we find a very good agreement with previous analyses, while the nonresonant ones show significant deviations.
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| 5. |
- Dutz, H, et al.
(author)
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Experimental check of the Gerasimov-Drell-Hearn sum rule for H-1
- 2004
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In: Physical Review Letters. - 1079-7114. ; 93:3
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Journal article (peer-reviewed)abstract
- For the first time we checked the fundamental Gerasimov-Drell-Hearn (GDH) sum rule for the proton experimentally in the photon energy range from 0.2-2.9 GeV with the tagged photon facilities at MAMI (Mainz) and ELSA (Bonn). New data of the doubly polarized total cross section difference are presented in the energy range from 1.6 to 2.9 GeV. The contribution to the GDH integral from 0.2-2.9 GeV yields [254+/-5(stat)+/-12(syst)] mub with negative contributions in the Regge regime at photon energies above 2.1 GeV. This trend supports the validity of the GDH sum rule.
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| 6. |
- Dutz, H, et al.
(author)
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First measurement of the Gerasimov-Drell-Hearn sum rule for H-1 from 0.7 to 1.8 GeV at ELSA
- 2003
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In: Physical Review Letters. - 1079-7114. ; 91:19: 192001
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Journal article (peer-reviewed)abstract
- To verify the fundamental Gerasimov-Drell-Hearn (GDH) sum rule for the first time experimentally, we measured the helicity dependent total photoabsorption cross section with circularly polarized real photons and longitudinally polarized nucleons in the photon energy range 0.68-1.82 GeV with the tagged photon facility at ELSA. The experiment was carried out with a 4pi detection system, a circularly polarized tagged photon beam, and a frozen spin polarized proton target. The contribution to the GDH sum rule in this photon energy range is [49.9+/-2.4(stat)+/-2.2(syst)] mub.
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| 7. |
- Hao, Qi, et al.
(author)
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Cooperative Scheduling for Inter-Enterprise Manufacturing Resources Sharing
- 2003
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Conference paper (peer-reviewed)abstract
- This paper presents a cooperative virtual enterprise approach targeting the manufacturing resource sharing among small and medium enterprises. With intelligent agents and Web Services technologies being adopted, the proposed approach possesses a number of distinguishing characteristics, such as loosely-coupled distributed architecture, internal privacy protection, secure separation of information and autonomous operation. An enterprise model, partner search and selection mechanisms, coordination modes and operation monitoring mechanisms are presented in details. The proposed approach emphasizes the enterprise to maximize its profitability, which is always regarded as a higher priority over other concerns.
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| 8. |
- Kaminsky, DA, et al.
(author)
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Oscillation mechanics of the human lung periphery in asthma
- 2004
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In: Journal of Applied Physiology. - : American Physiological Society. - 1522-1601 .- 8750-7587. ; 97:5, s. 1849-1858
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Journal article (peer-reviewed)abstract
- To more precisely measure the mechanical properties of the lung periphery in asthma, we have developed a forced oscillation technique that applies a broad-band flow signal through a wedged bronchoscope. We interpreted the data from four healthy and eight mildly asthmatic subjects in terms of an anatomically accurate computer model of the wedged segment. There was substantial overlap in impedance between the two groups, with resistance ( R) showing minimal frequency dependence and elastance (E) showing positive and negative frequency dependence across subjects. After direct instillation of methacholine, R rose in both groups, but compared with healthy subjects, the asthmatic subjects displayed upward, parallel shifts in their dose-response curves. The baseline frequency-response patterns of E were enhanced after methacholine. Frequency dependencies of R and E were well reproduced in two normal subjects by a computational model that employed rigid airways connected to constant-phase tissue units but were better reproduced in the other two normal and three asthmatic subjects when the model employed heterogeneous, peripheral airway narrowing and compliant airways. To capture the frequency dependencies of R and E in the remaining five asthmatic subjects, the model was modified by increasing airway wall stiffness. These results indicate that the lung periphery of mildly asthmatic subjects is not well distinguished from that of healthy subjects by measurement of mechanical impedance at baseline, but group differences are seen after challenge with methacholine. Modeling of the response suggests that variable contributions of airway narrowing and wall compliance are operative in determining overall mechanical impedance of the lung periphery in humans with asthma, likely reflecting the functional consequences of airway inflammation and remodeling.
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| 9. |
- Ongena, J., et al.
(author)
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Recent progress on JET towards the ITER reference mode of operation at high density
- 2001
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In: Plasma Physics and Controlled Fusion. - 0741-3335 .- 1361-6587. ; 43, s. A11-A30
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Journal article (peer-reviewed)abstract
- Recent progress towards obtaining high density and high confinement in JET as required for the ITER reference scenario at Q = 10 is summarized. Plasmas with simultaneous confinement H-98(y.2) = 1 and densities up to n/n(Gw) similar to 1 are now routinely obtained. This has been possible (i) by using plasmas at high (delta similar to 0.5) and medium (delta similar to 0.3-0.4) triangularity with sufficient heating power to maintain Type I ELMs, (ii) with impurity seeded plasmas at high (delta similar to 0.5) and low (delta less than or equal to 0.2) triangularity, (iii) with an optimized pellet injection sequence, maintaining the energy confinement and raising the density, and (iv) by carefully tuning the gas puff rate leading to plasmas with peaked density profiles and good confinement at long time scales. These high performance discharges exhibit Type I ELMs, with a new and more favourable behaviour observed at high densities, requiring further studies. Techniques for a possible mitigation of these ELMs are discussed, and first promising results are obtained with impurity seeding in discharges at high triangularity. Scaling studies using the new data of this year show a strong dependence of confinement on upper triangularity, density and proximity to the Greenwald limit. Observed MHD instabilities and methods to avoid these in high density and high confinement plasmas are discussed.
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| 10. |
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| 11. |
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| 12. |
- Shen, Weiming, et al.
(author)
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Reference Architecture for Internet Based Intelligent Shop Floors
- 2000
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In: Proceedings of SPIE Conference on Network Intelligence. - : SPIE - International Society for Optical Engineering. ; , s. 63-72
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Conference paper (peer-reviewed)abstract
- Global competitiveness is causing manufacturing companies to change the way they do business. New ways of viewing markets and competition have led the movement from legacy information systems to Internet-based environments. Success in manufacturing depends on being able to respond quickly, accurately and consistently to the changing needs of the marketplace. The need to control and optimize processes and to vary the necessary parameters to obtain the best product on time and on specification has fostered a change from centralized or hierarchical to distributed manufacturing control systems. This paper proposes a reference architecture for Internet-based intelligent shop floors. Internet, Web technologies, and intelligent agents are the key technologies adopted in this approach. The reference architecture provides the framework for components of a complex control system to work together as a whole rather than as a disjoint set. It encompasses both information architecture and integration methodologies. The primary aspects of the reference architecture under consideration include: (1) statement of scope and purpose; (2) domain analysis; (3) architectural specification; and (4) methodology for architectural development and system design.
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| 13. |
- Shen, Weiming, et al.
(author)
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XML-Based Message Services for Internet Based Intelligent Shop Floors
- 2001
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In: Proceedings Volume 4566, Internet-based Enterprise Integration and Management. - : SPIE - International Society for Optical Engineering. ; , s. 135-144
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Conference paper (peer-reviewed)abstract
- Previously, we reported some preliminary results of our long-term research work on iShopFloor (Intelligent Shop Floor). This paper reports some of our recent work on the implementation of XML-based message services for Internet-based intelligent shop floors. The objective is to investigate XML for message exchange among Internet-based shop floor devices that are represented by intelligent agents. The paper discusses the advantages of using XML for message services and presents our initial implementation. From this implementation, we have seen some advantages, including: (1) simplification and standardization of message services in Internet-based intelligent shop floors; (2) facilitation of the integration of an agent-based scheduling system with other intelligent shop floor systems, including Web-based shop floor monitoring and control systems, etc.
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| 14. |
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| 15. |
- Steward, C. G., et al.
(author)
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Severe pulmonary hypertension: a frequent complication of stem cell transplantation for malignant infantile osteopetrosis
- 2004
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In: Br J Haematol. - 0007-1048. ; 124:1, s. 63-71
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Journal article (peer-reviewed)abstract
- This report describes eight infants who developed acute severe pulmonary arterial hypertension (PAH) at days -2 to +89 after allogeneic stem cell transplantation (SCT) for malignant infantile osteopetrosis (MIOP). They were taken from a total of 28 children (frequency 29%) transplanted for this disease at three institutions between 1996 and 2002. Typical presentations were acute dyspnoea, hypoxia and brady/tachycardia usually in the absence of fever, crepitations or other evidence of infection. Six patients (75%) required assisted ventilation and five (62%) died. There was clinical or pathological evidence of veno-occlusive disease (VOD) in three children, but absence of VOD in the remaining five suggests that a separate disease process may be responsible for the PAH. Responses to nitric oxide (NO), defibrotide (DF), nicardipine and steroids in varying combinations were disappointing. Three children showed sustained improvement after administration of epoprostenol (EP, prostacyclin) in conjunction with NO and/or DF and remain well and free of PAH 25, 31 and 32 months post-transplant. PAH must therefore be excluded in any child who becomes acutely breathless after SCT for osteopetrosis.
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| 16. |
- Wang, Lihui, et al.
(author)
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A Web-based Collaborative Workspace Using Java 3D
- 2001
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In: The Sixth International Conference on, 2001 Computer Supported Cooperative Work in Design. - : IEEE. - 0660184931 ; , s. 77-82
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Conference paper (peer-reviewed)abstract
- The paper presents a framework for building Web-based collaborative workspaces using the latest Java technologies-Java 3D, JavaServer Page (JSP), and Java Servlet. This Web-based approach allows designers, engineers and production managers to share a common workspace that can be used for design review, production monitoring, remote control, and troubleshooting, based on a set of interactive Java 3D models that represent the physical world with common interests. Following a brief overview of the related research work, the paper discusses the Java 3D concept from its scene graph structure to behavior control, and explains our approach to building Web-based collaborative workspaces using Java 3D. The proposed framework uses the popular client-server architecture and view-control-model design pattern with a secured session control. Control logic and the interfaces, which interact with the real world, are handled by an application server through servlets. The benefits enabled by the framework include reduced network traffic, increased flexibility of remote monitoring, interactive control, Web-based synchronous collaboration and quick response. It also shows significant potential for various Web-based real-time and distributed applications.
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| 17. |
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| 18. |
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| 19. |
- Wang, Lihui, et al.
(author)
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Java 3D-Enabled Cyber Workspace
- 2002
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In: Communications of the ACM. - : Association for Computing Machinery (ACM). - 0001-0782 .- 1557-7317. ; 45:11, s. 45-49
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Journal article (peer-reviewed)abstract
- Along with the browser paradigm, Java has fundamentally changed the work environment, helping produce compelling applications for collaborating over the Internet.
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| 20. |
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| 21. |
- Xu, Y., et al.
(author)
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A Security Framework for Collaborative Distributed System Control at the Device-Level
- 2003
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In: INDIN 2003. - : Institute of Electrical and Electronics Engineers (IEEE). - 0780382005 ; , s. 192-198
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Conference paper (peer-reviewed)abstract
- In today's globalized business world, outsourcing, joint ventures, and cross-border collaborations have led to work environments that are geographically distributed across organizational and national boundaries. There are critical research needs to develop highly secured collaborative work environments and security solutions for deployment, configuration, monitoring, and device control of interoperating services. We present a well-shaped security framework for distributed system control with a focus on device-level system control, monitoring and services reconfiguration in open and dynamic environments. The characteristics of portability, reconfigurability, interoperability, and interchangeability of these new environments are considered as key factors to produce new security risks and challenges. By adopting public key cryptography, software agent and XML binding technologies, the major security problems of authenticity, integrity, confidentiality, and safe execution are addressed in this framework. The core modules for secure task delivery and execution are presented in detail.
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| 22. |
- Zhang, Dan, et al.
(author)
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An Integrated Virtual Validation System for Parallel Kinematic Machine Analysis and Design
- 2003
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In: Proceedings of the ASME Design Engineering Technical Conference. ; , s. 1149-1158
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Conference paper (peer-reviewed)abstract
- Selecting a configuration for a machine tool that will best suit the needs of a forecast set of requirements can be a difficulty and costly exercise. This problem can now be addressed using an integrated virtual validation system. The system includes kinematic/dynamic analysis, kinetostatic model, CAD module, FEM module, CAM module, optimization module and visual environment for simulation and collision detection of the machining and deburring. It is an integration of the parallel kinematic machines (PKM) design, analysis, optimization and simulation. In this paper, the integrated virtual system is described in a detail, a prototype of a 3-dof PKM is modeled, analyzed, optimized and remote controlled with the proposed system. Some results and simulations are also given. Its effectiveness is shown with the results obtained by NRC-IMTI during the design of the 3-dof NRC PKM.
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| 23. |
- Zhang, Dan, et al.
(author)
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Modelling and Control of PKM in an Integrated Environment
- 2003
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In: Proceedings of the ASME Design Engineering Technical Conference. - : ASME Press. ; , s. 67-76
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Conference paper (peer-reviewed)abstract
- This paper introduces an integrated validation system that consists of the following modular components: kinematic/dynamic analysis module, kinetostatic model, CAD module, FEM module, CAM module, optimization module and visual environment for remote control. In this paper, authors focus mainly on the modules of kinetostatic modeling, dynamic modeling, PKM design optimization, and remote control realization. The prototype of a 3-dof PKM developed at NRC-IMTI is used as an example throughout this paper.
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