1. |
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2. |
- Klionsky, Daniel J., et al.
(author)
-
Guidelines for the use and interpretation of assays for monitoring autophagy
- 2012
-
In: Autophagy. - : Informa UK Limited. - 1554-8635 .- 1554-8627. ; 8:4, s. 445-544
-
Research review (peer-reviewed)abstract
- In 2008 we published the first set of guidelines for standardizing research in autophagy. Since then, research on this topic has continued to accelerate, and many new scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Accordingly, it is important to update these guidelines for monitoring autophagy in different organisms. Various reviews have described the range of assays that have been used for this purpose. Nevertheless, there continues to be confusion regarding acceptable methods to measure autophagy, especially in multicellular eukaryotes. A key point that needs to be emphasized is that there is a difference between measurements that monitor the numbers or volume of autophagic elements (e.g., autophagosomes or autolysosomes) at any stage of the autophagic process vs. those that measure flux through the autophagy pathway (i.e., the complete process); thus, a block in macroautophagy that results in autophagosome accumulation needs to be differentiated from stimuli that result in increased autophagic activity, defined as increased autophagy induction coupled with increased delivery to, and degradation within, lysosomes (in most higher eukaryotes and some protists such as Dictyostelium) or the vacuole (in plants and fungi). In other words, it is especially important that investigators new to the field understand that the appearance of more autophagosomes does not necessarily equate with more autophagy. In fact, in many cases, autophagosomes accumulate because of a block in trafficking to lysosomes without a concomitant change in autophagosome biogenesis, whereas an increase in autolysosomes may reflect a reduction in degradative activity. Here, we present a set of guidelines for the selection and interpretation of methods for use by investigators who aim to examine macroautophagy and related processes, as well as for reviewers who need to provide realistic and reasonable critiques of papers that are focused on these processes. These guidelines are not meant to be a formulaic set of rules, because the appropriate assays depend in part on the question being asked and the system being used. In addition, we emphasize that no individual assay is guaranteed to be the most appropriate one in every situation, and we strongly recommend the use of multiple assays to monitor autophagy. In these guidelines, we consider these various methods of assessing autophagy and what information can, or cannot, be obtained from them. Finally, by discussing the merits and limits of particular autophagy assays, we hope to encourage technical innovation in the field.
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3. |
- Abelev, Betty, et al.
(author)
-
Long-range angular correlations on the near and away side in p-Pb collisions at root S-NN=5.02 TeV
- 2013
-
In: Physics Letters. Section B: Nuclear, Elementary Particle and High-Energy Physics. - : Elsevier BV. - 0370-2693. ; 719:1-3, s. 29-41
-
Journal article (peer-reviewed)abstract
- Angular correlations between charged trigger and associated particles are measured by the ALICE detector in p-Pb collisions at a nucleon-nucleon centre-of-mass energy of 5.02 TeV for transverse momentum ranges within 0.5 < P-T,P-assoc < P-T,P-trig < 4 GeV/c. The correlations are measured over two units of pseudorapidity and full azimuthal angle in different intervals of event multiplicity, and expressed as associated yield per trigger particle. Two long-range ridge-like structures, one on the near side and one on the away side, are observed when the per-trigger yield obtained in low-multiplicity events is subtracted from the one in high-multiplicity events. The excess on the near-side is qualitatively similar to that recently reported by the CMS Collaboration, while the excess on the away-side is reported for the first time. The two-ridge structure projected onto azimuthal angle is quantified with the second and third Fourier coefficients as well as by near-side and away-side yields and widths. The yields on the near side and on the away side are equal within the uncertainties for all studied event multiplicity and p(T) bins, and the widths show no significant evolution with event multiplicity or p(T). These findings suggest that the near-side ridge is accompanied by an essentially identical away-side ridge. (c) 2013 CERN. Published by Elsevier B.V. All rights reserved.
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4. |
- Abelev, Betty, et al.
(author)
-
Measurement of prompt J/psi and beauty hadron production cross sections at mid-rapidity in pp collisions at root s=7 TeV
- 2012
-
In: Journal of High Energy Physics. - 1029-8479. ; :11
-
Journal article (peer-reviewed)abstract
- The ALICE experiment at the LHC has studied J/psi production at mid-rapidity in pp collisions at root s = 7 TeV through its electron pair decay on a data sample corresponding to an integrated luminosity L-int = 5.6 nb(-1). The fraction of J/psi from the decay of long-lived beauty hadrons was determined for J/psi candidates with transverse momentum p(t) > 1,3 GeV/c and rapidity vertical bar y vertical bar < 0.9. The cross section for prompt J/psi mesons, i.e. directly produced J/psi and prompt decays of heavier charmonium states such as the psi(2S) and chi(c) resonances, is sigma(prompt J/psi) (p(t) > 1.3 GeV/c, vertical bar y vertical bar < 0.9) = 8.3 +/- 0.8(stat.) +/- 1.1 (syst.)(-1.4)(+1.5) (syst. pol.) mu b. The cross section for the production of b-hadrons decaying to J/psi with p(t) > 1.3 GeV/c and vertical bar y vertical bar < 0.9 is a sigma(J/psi <- hB) (p(t) > 1.3 GeV/c, vertical bar y vertical bar < 0.9) = 1.46 +/- 0.38 (stat.)(-0.32)(+0.26) (syst.) mu b. The results are compared to QCD model predictions. The shape of the p(t) and y distributions of b-quarks predicted by perturbative QCD model calculations are used to extrapolate the measured cross section to derive the b (b) over bar pair total cross section and d sigma/dy at mid-rapidity.
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5. |
- Birney, Ewan, et al.
(author)
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Identification and analysis of functional elements in 1% of the human genome by the ENCODE pilot project
- 2007
-
In: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 447:7146, s. 799-816
-
Journal article (peer-reviewed)abstract
- We report the generation and analysis of functional data from multiple, diverse experiments performed on a targeted 1% of the human genome as part of the pilot phase of the ENCODE Project. These data have been further integrated and augmented by a number of evolutionary and computational analyses. Together, our results advance the collective knowledge about human genome function in several major areas. First, our studies provide convincing evidence that the genome is pervasively transcribed, such that the majority of its bases can be found in primary transcripts, including non-protein-coding transcripts, and those that extensively overlap one another. Second, systematic examination of transcriptional regulation has yielded new understanding about transcription start sites, including their relationship to specific regulatory sequences and features of chromatin accessibility and histone modification. Third, a more sophisticated view of chromatin structure has emerged, including its inter-relationship with DNA replication and transcriptional regulation. Finally, integration of these new sources of information, in particular with respect to mammalian evolution based on inter- and intra-species sequence comparisons, has yielded new mechanistic and evolutionary insights concerning the functional landscape of the human genome. Together, these studies are defining a path for pursuit of a more comprehensive characterization of human genome function.
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6. |
- Zhao, Chaoyang, et al.
(author)
-
A massive expansion of effector genes underlies gall-formation in the wheat pest Mayetiola destructor
- 2015
-
In: Current Biology. - : Elsevier BV. - 1879-0445 .- 0960-9822. ; 25:5, s. 613-620
-
Journal article (peer-reviewed)abstract
- Gall-forming arthropods are highly specialized herbivores that, in combination with their hosts, produce extended phenotypes with unique morphologies [1]. Many are economically important, and others have improved our understanding of ecology and adaptive radiation [2]. However, the mechanisms that these arthropods use to induce plant galls are poorly understood. We sequenced the genome of the Hessian fly (Mayetiola destructor; Diptera: Cecidomyiidae), a plant parasitic gall midge and a pest of wheat (Triticum spp.), with the aim of identifying genic modifications that contribute to its plant-parasitic lifestyle. Among several adaptive modifications, we discovered an expansive reservoir of potential effector proteins. Nearly 5% of the 20,163 predicted gene models matched putative effector gene transcripts present in the M. destructor larval salivary gland. Another 466 putative effectors were discovered among the genes that have no sequence similarities in other organisms. The largest known arthropod gene family (family SSGP-71) was also discovered within the effector reservoir. SSGP-71 proteins lack sequence homologies to other proteins, but their structures resemble both ubiquitin E3 ligases in plants and E3-ligase-mimicking effectors in plant pathogenic bacteria. SSGP-71 proteins and wheat Skp proteins interact in vivo. Mutations in different SSGP-71 genes avoid the effector-triggered immunity that is directed by the wheat resistance genes H6 and H9. Results point to effectors as the agents responsible for arthropod-induced plant gall formation.
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7. |
- Abelev, Betty, et al.
(author)
-
Underlying Event measurements in pp collisions at root s=0.9 and 7 TeV with the ALICE experiment at the LHC
- 2012
-
In: Journal of High Energy Physics. - 1029-8479. ; :7
-
Journal article (peer-reviewed)abstract
- We present measurements of Underlying Event observables in pp collisions at root s = 0 : 9 and 7 TeV. The analysis is performed as a function of the highest charged-particle transverse momentum p(T),L-T in the event. Different regions are defined with respect to the azimuthal direction of the leading (highest transverse momentum) track: Toward, Transverse and Away. The Toward and Away regions collect the fragmentation products of the hardest partonic interaction. The Transverse region is expected to be most sensitive to the Underlying Event activity. The study is performed with charged particles above three different p(T) thresholds: 0.15, 0.5 and 1.0 GeV/c. In the Transverse region we observe an increase in the multiplicity of a factor 2-3 between the lower and higher collision energies, depending on the track p(T) threshold considered. Data are compared to PYTHIA 6.4, PYTHIA 8.1 and PHOJET. On average, all models considered underestimate the multiplicity and summed p(T) in the Transverse region by about 10-30%.
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8. |
- Al Karim, Miftah, et al.
(author)
-
Synchrophasor-based data mining for power system fault analysis
- 2012
-
In: Innovative Smart Grid Technologies (ISGT Europe), 2012 3rd IEEE PES International Conference and Exhibition on. - : IEEE. - 9781467325974 ; , s. 6465843-
-
Conference paper (peer-reviewed)abstract
- Phasor measurement units can provide high resolution and synchronized power system data, which can be effectively utilized for the implementation of data mining techniques. Data mining, based on pattern recognition algorithms can be of significant help for power system analysis, as high definition data is often complex to comprehend. In this paper three pattern recognition algorithms are applied to perform the data mining tasks. The deployment is carried out firstly for fault data classification, secondly for checking which faults are occurring more frequently and thirdly for identifying the root cause of a fault by clustering the parameters behind each scenario. For such purposes three algorithms are chosen, k-Nearest Neighbor, Naïve Bayes and the k-means Clustering.
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9. |
- Babazadeh, Davood, et al.
(author)
-
A Platform for Wide Area Monitoring and Control System ICT Analysis and Development
- 2013
-
In: 2013 IEEE Grenoble Conference PowerTech, POWERTECH 2013. - : IEEE. - 9781467356695
-
Conference paper (peer-reviewed)abstract
- PMU-based Wide Area Monitoring and Control(WAMC) system is introduced to improve the monitoring ofpower grid across large geographic areas and control the gridusing more efficient and smart applications. The performance ofWAMC applications in real power system scenarios and impactof their supporting Information and Communication Technology(ICT) on the data quality can be quantified and analyzed bypseudo-real co-simulation test beds. The purpose of this study isto propose and develop a WAMC testing platform to facilitate thereal-time simulation of dynamic power grid, the ICTinfrastructure that overlays the grid and WAMS applications.The platform consists of OPNET, a powerful communicationnetwork emulator, connected to a real-time power systemsimulator through virtualized PMU device. The end pointstations such as Phasor Data Concentrator or PMU-basedapplications are also linked to the platform through OPNET’sreal-simulation gateway called SITL (System-In-The-Loop). Toassess the performance of the platform architecture, a case studyhas been performed with five PMUs which collect the data from apower model and deliver to PMU-based mode-estimationapplication over a typical communication network. In this study,the results explicitly intend to quantify the effect of networkprotocols on data delay.
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10. |
- Babazadeh, Davood, et al.
(author)
-
Real-Time Smart Grid Application Testing using OPNET SITL
- 2012
-
Conference paper (peer-reviewed)abstract
- Phasor -based Wide Area Monitoring and Control (WAMC) system promise to improve the monitoring of power grid across large geographic areas and accordingly controlling grid in more efficient and intelligent ways. In order to have confidence on the correctness, performance and reliability of applications used in WAMC system in real world scenarios, pseudo-real test beds where the requirements for the applications and their supporting Information and Communication Technology (ICT) can be quantified and analyzed. In this paper, a WAMC system testing platform is proposed to facilitate the real-time simulation of dynamic power grid, the ICT infrastructure that overlays the grid and WAMC applications. The proposed platform consists of OPNET as a powerful communication network simulator connected to real-time power system simulator on one side through virtualized Phasor Measurement Unit device, and linked to end point stations such as Phasor Data Concentrator or application on the other side through OPNET’s real-simulation gateway. A set of proof of concept scenarios using this framework is presented.
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11. |
- Badr, Hussein O., et al.
(author)
-
Bottom-up, scalable synthesis of anatase nanofilament-based two-dimensional titanium carbo-oxide flakes
- 2022
-
In: Materials Today. - : ELSEVIER SCI LTD. - 1369-7021 .- 1873-4103. ; 54
-
Journal article (peer-reviewed)abstract
- Two-dimensional (2D) materials offer advantages that their 3D counterparts do not. The conventional method for the bulk synthesis of 2D materials has predominantly been through etching layered solids. Herein, we convert - through a bottom-up approach - 10 binary and ternary titanium carbides, nitrides, borides, phosphides, and silicides into 2D flakes by immersing them in a tetramethylammonium hydroxide solution at temperatures in the 25-85 degrees C range. Based on X-ray diffraction, density functional theory, X-ray photoelectron, electron energy loss, Raman, X-ray absorption near edge structure spectroscopies, transmission and scanning electron microscope images and selected area diffraction, we conclude that the resulting flakes are carbon containing anatase-based layers that are, in turn, comprised of approximate to 6 x 10 angstrom(2) nanofilaments in cross-section some of which are few microns long. Electrodes made from some of these films performed well in lithium-ion and lithium-sulphur systems. These materials also reduce the viability of cancer cells thus showing potential in biomedical applications. Synthesizing 2D materials, at near ambient conditions, with non-layered, inexpensive, green precursors (e.g., TiC) is paradigm shifting and will undoubtedly open new and exciting avenues of research and applications.
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12. |
- Björkman, Gunnar, et al.
(author)
-
SCADA system architectures
- 2010
-
Other publication (other academic/artistic)abstract
- The aim of deliverable 2.3 in the VIKING is to catalogue architecture patterns or reference architectures, i.e. commonly deployed solutions, for SCADA systems. These patterns are represented as a set of descriptions that capture the vast majority of SCADA systems’ architecture on a high level. The patterns developed in this report focus on: - Software services in SCADA systems and software services which SCADA systems exchange data with. - Data flows among these services. - How services are placed in different security zones (network zones). The purpose of the SCADA architecture patterns is to clarify how SCADA systems are commonly designed by employing a stringent model framework. Internal in the project the SCADA patterns will be used to develop SCADA system design models that reflect some typical systems deployed in industry. These models will be used in other work packages and deliverables in the VIKING project.
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13. |
- Bottura, Riccardo, et al.
(author)
-
SITL and HLA Co-simulation Platforms : Tools for Analysis of the Integrated ICT and Electric Power System
- 2013
-
In: 2013 IEEE EUROCON. - 9781467322300
-
Conference paper (peer-reviewed)abstract
- Due to the necessity of developing analysis tools inthe integrated ICT and power system domain, this paperdescribes and compares the architecture and configuration oftwo different co-simulation approaches called SITL and HLACo-simulation platforms. We provide several details on theirimplementation and present their features by means of theresults obtained for two test cases. The paper aims at clarifyingthe type of analysis that can be effectively carried out by usingthe two different platforms. Both platforms make use of thecommunication network simulator OPNET (Optimum NetworkPerformance). One of the two platforms operates in real time, inorder to perform system-in-the-loop (SITL) simulations. Theother platform is based on the interface between OPNET and thepower network simulation environment EMTP (ElectromagneticTransient Program). The interface is based on the application ofthe High-Level Architecture (HLA) standard.
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14. |
- Chen, Fangjun, et al.
(author)
-
Comprehensive kinetic modeling and product distribution for pyrolysis of pulp and paper mill sludge
- 2024
-
In: Science of the Total Environment. - 0048-9697 .- 1879-1026. ; 924
-
Journal article (peer-reviewed)abstract
- Pyrolysis holds immense potential for clean treatment of pulp and paper mill sludge (PPMS), enabling efficient energy and chemical recovery. However, current understanding of PPMS pyrolysis kinetics and product characteristics remains incomplete. This study conducted detailed modeling of pyrolysis kinetics for two typical PPMSs from a wastepaper pulp and paper mill, namely, deinking sludge (PPMS-DS) and sewage sludge (PPMS-SS), and analyzed comprehensively pyrolysis products. The results show that apparent activation energy of PPMS-DS (169.25–226.82 kJ/mol) and PPMS-SS (189.29–411.21 kJ/mol) pyrolysis undergoes significant change, with numerous parallel reactions present. A distributed activation energy model with dual logistic distributions proves to be suitable for modeling thermal decomposition kinetics of both PPMS-DS and PPMS-SS, with coefficient of determination >0.999 and relative root mean square error <1.99 %. High temperature promotes decomposition of solid organic materials in PPMS, and maximum tar yield for both PPMS-DS (53.90 wt%, daf) and PPMS-SS (56.48 wt%, daf) is achieved at around 500 °C. Higher levels of styrene (24.45 % for PPMS-DS and 14.71 % for PPMS-SS) and ethylbenzene (8.61 % for PPMS-DS and 8.33 % for PPMS-SS) are detected in tar and could be used as chemicals. This work shows great potential to propel development of PPMS pyrolysis technology, enabling green and sustainable production in pulp and paper industry.
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15. |
- Chen, Hui, et al.
(author)
-
Characterization of insolubilized humic acid and its sorption behaviors
- 2009
-
In: Environmental Geology. - : Springer Science and Business Media LLC. - 0943-0105 .- 1432-0495. ; 57:8, s. 1847-1853
-
Journal article (peer-reviewed)abstract
- Insolubilized humic acid (IHA) was prepared in the laboratory by heating approach. Through the comparison between the endothermic peaks, optimal heating temperature was determined to be 330A degrees C. The modified IHA then was characterized by TG-DTA, SEM, FTIR, element analysis, and nitrogen adsorption-desorption isotherms. The removal efficiency of p-nitrophenol from the aqueous solution by adsorption onto solid IHA surfaces was shown to be a function of pH, reaction temperature, and p-nitrophenol concentration. Adsorption equilibrium data satisfactorily fitted the Langmuir adsorption isotherm. Under a certain concentration range, the removal rate of p-nitrophenol at pH 3.5 could reach 24, 29, and 35 mg/g at a temperature of 25, 35, and 45 +/- 0.1A degrees C. The results suggest that IHA could play a role as a potential efficient absorbent to remove organic contaminants, e.g., utilized to purify water contaminated by organic compounds.
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16. |
- Chenine, Moustafa, et al.
(author)
-
Survey on Priorities and Communication Requirements for PMU-based Applications in the Nordic Region
- 2009
-
In: 2009 IEEE Bucharest PowerTech. - : IEEE. - 9781424422340 ; , s. 1183-1190
-
Conference paper (peer-reviewed)abstract
- Phasor based Wide Area Monitoring and Control Systems (WAMC) promise to offer more accurate and timely data on the state of the power system, thus, increasing the possibilities to manage the system at a more efficient and responsive level and apply wide area control and protection schemes. This paper presents results of a survey on communications and technical requirements for applications based on Phasor Measurement Units (PMU). The survey was carried out in the Nordic Region with participants from Transmission System Operators (TSOs) and researchers. The survey focused on documenting the stage of research and development among TSOs and researchers in the Nordic Region, as well as, their plans and visions for the future. This includes planned PMU deployments and prioritization of PMU based applications. Furthermore, a significant part of the survey was an elicitation of communication requirements for applications based on PMU data. In the paper, an examination of the time requirements for these applications in terms of delays and samples per second and comparison similar published specifications is provided.
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17. |
- Ehlers, Todd A., et al.
(author)
-
Past, present, and future geo-biosphere interactions on the Tibetan Plateau and implications for permafrost
- 2022
-
In: Earth-Science Reviews. - : Elsevier BV. - 0012-8252. ; 234
-
Journal article (peer-reviewed)abstract
- Interactions between the atmosphere, biosphere, cryosphere, hydrosphere, and geosphere are most active in the critical zone, a region extending from the tops of trees to the top of unweathered bedrock. Changes in one or more of these spheres can result in a cascade of changes throughout the system in ways that are often poorly understood. Here we investigate how past and present climate change have impacted permafrost, hydrology, and ecosystems on the Tibetan Plateau. We do this by compiling existing climate, hydrologic, cryosphere, biosphere, and geologic studies documenting change over decadal to glacial-interglacial timescales and longer. Our emphasis is on showing present-day trends in environmental change and how plateau ecosystems have largely flourished under warmer and wetter periods in the geologic past. We identify two future pathways that could lead to either a favorable greening or unfavorable degradation and desiccation of plateau ecosystems. Both paths are plausible given the available evidence. We contend that the key to which pathway future generations experience lies in what, if any, human intervention measures are implemented. We conclude with suggested management strategies that can be implemented to facilitate a future greening of the Tibetan Plateau.
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18. |
- Estrada, Karol, et al.
(author)
-
Genome-wide meta-analysis identifies 56 bone mineral density loci and reveals 14 loci associated with risk of fracture.
- 2012
-
In: Nature genetics. - : Springer Science and Business Media LLC. - 1546-1718 .- 1061-4036. ; 44:5, s. 491-501
-
Journal article (peer-reviewed)abstract
- Bone mineral density (BMD) is the most widely used predictor of fracture risk. We performed the largest meta-analysis to date on lumbar spine and femoral neck BMD, including 17 genome-wide association studies and 32,961 individuals of European and east Asian ancestry. We tested the top BMD-associated markers for replication in 50,933 independent subjects and for association with risk of low-trauma fracture in 31,016 individuals with a history of fracture (cases) and 102,444 controls. We identified 56 loci (32 new) associated with BMD at genome-wide significance (P < 5 × 10(-8)). Several of these factors cluster within the RANK-RANKL-OPG, mesenchymal stem cell differentiation, endochondral ossification and Wnt signaling pathways. However, we also discovered loci that were localized to genes not known to have a role in bone biology. Fourteen BMD-associated loci were also associated with fracture risk (P < 5 × 10(-4), Bonferroni corrected), of which six reached P < 5 × 10(-8), including at 18p11.21 (FAM210A), 7q21.3 (SLC25A13), 11q13.2 (LRP5), 4q22.1 (MEPE), 2p16.2 (SPTBN1) and 10q21.1 (DKK1). These findings shed light on the genetic architecture and pathophysiological mechanisms underlying BMD variation and fracture susceptibility.
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19. |
- Franke, Ulrik, et al.
(author)
-
Enterprise Architecture analysis using Fault Trees and MODAF
- 2009
-
In: Proceedings of the Forum at the CAiSE 2009 Conference. ; , s. 61-66
-
Conference paper (peer-reviewed)abstract
- Analysis of dependencies between information systems, business processes, and strategic goals is an important part of the discipline of Enterprise Architecture (EA). However, EA models typically provide only visual and qualitative decision support. This paper shows how EA frameworks for dependency analysis can be extended into the realm of quantitative methods by the use of techniques from Fault Tree Analysis (FTA). Using MODAF, the UK Ministry of Defence Architecture Framework as an example, we give a list of criteria for the extraction of a metamodel for FTA use, and provide such a metamodel for MODAF. Furthermore, we use this MODAF FTA metamodel to perform dependency analysis on a sample MODAF model.
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20. |
- Fu, Hongyan, et al.
(author)
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Tunable all-optical microwave notch filter with a negative tap based on a semiconductor optical amplifier and a dispersive medium
- 2009
-
In: Optics and Laser Technology. - : Elsevier BV. - 0030-3992 .- 1879-2545. ; 41:3, s. 213-216
-
Journal article (peer-reviewed)abstract
- A tunable all-optical microwave notch filter with a negative tap based on a semiconductor optical amplifier and a dispersive medium is demonstrated. A negative tap is realized through the cross gain modulation in the semiconductor optical amplifier. The free spectrum range of the notch filter can be tuned by tuning the wavelength of one of the two laser sources. The influence of the amplitude mismatch of the two lasers on the performance of the filter is analyzed. The present notch filter is easy to implement and cost-effective.
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21. |
- Han, Xue, et al.
(author)
-
Empirical analysis for Distributed Energy Resources' impact on future distribution network
- 2012
-
In: Energy Conference and Exhibition (ENERGYCON), 2012 IEEE International. - : IEEE. - 9781467314541 ; , s. 731-737
-
Conference paper (peer-reviewed)abstract
- There has been a large body of statements claiming that the large scale deployment of Distributed Energy Resources (DERs) will eventually reshape the future distribution grid operation in various ways. Thus, it is interesting to introduce a platform to interpret to what extent the power system operation will be alternated. In this paper, quantitative results in terms of how the future distribution grid will be changed by the deployment of distributed generation, active demand and electric vehicles, are presented. The analysis is based on the conditions for both a radial and a meshed distribution network. The input parameters are based on the current and envisioned DER deployment scenarios proposed for Sweden.
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22. |
- Han, Xue, et al.
(author)
-
Modelling Framework and the Quantitative Analysis of Distributed Energy Resources in Future Distribution Networks
- 2013
-
In: International Journal of Emerging Electric Power Systems. - : De Gruyter. - 2194-5756 .- 1553-779X. ; 14:5, s. 421-431
-
Journal article (peer-reviewed)abstract
- There has been a large body of statements claiming that the large-scale deployment of Distributed Energy Resources (DERs) could eventually reshape the future distribution grid operation in numerous ways. Thus, it is necessary to introduce a framework to measure to what extent the power system operation will be changed by various parameters of DERs. This article proposed a modelling framework for an overview analysis on the correlation between DERs. Furthermore, to validate the framework, the authors described the reference models of different categories of DERs with their unique characteristics, comprising distributed generation, active demand and electric vehicles. Subsequently, quantitative analysis was made on the basis of the current and envisioned DER deployment scenarios proposed for Sweden. Simulations are performed in two typical distribution network models for four seasons. The simulation results show that in general the DER deployment brings in the possibilities to reduce the power losses and voltage drops by compensating power from the local generation and optimizing the local load profiles.
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23. |
- He, Shu, et al.
(author)
-
A global assay of haemostasis which uses recombinant tissue factor and tissue-type plasminogen activator to measure the rate of fibrin formation and fibrin degradation in plasma
- 2007
-
In: Thrombosis and Haemostasis. - 0340-6245 .- 2567-689X. ; 98:4, s. 871-882
-
Journal article (peer-reviewed)abstract
- The global assay of Overall Haemostasis Potential we previously described has been refined. The coagulation cascade in platelet-poor plasma is triggered by adding a minimal dose of recombinant tissue factor together with purified phospholipids and calcium; fibrinolysis is initiated by adding recombinant tissue type-plasminogen activator in a concentration similar to what can be obtained during thrombolysis. Numerical differentials of optical densities reflecting rates of fibrin formation and degradation are calculated by a new software, and the Coagulation Profile (Cp) and the Fibrinolysis Profile (Fp) are determined. The combined effect of these counteractive systems is expressed as a ratio of Cp to Fp, called the Overall Haemostasis Index. Commercially available coagulant-deficient patient plasma samples and plasma with various amounts of added PAI-1 are examined; changes of fibrin turbidity demonstrate that this assay can determine Cp and Fp in a physiologically relevant way. Increased Cp and decreased Fp in prothrombotic patients, as well as expected effects of heparin or a thrombin inhibitor on Cp and Fp, suggest that our method can detect hypercoagulability and assist in monitoring antithrombotic treatment. Ongoing studies will show whether this simple assay can be of value in clinical routine.
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24. |
- Honeth, Nicholas, et al.
(author)
-
Decentralized topology inference of electrical distribution networks
- 2012
-
In: 2012 IEEE PES Innovative Smart Grid Technologies, ISGT 2012. - : IEEE. - 9781457721588
-
Conference paper (peer-reviewed)abstract
- Power system operation and control relies heavily on models for decision making. Topology is a critical part of producing these models and maintaining up-to-date topologies of electrical distribution networks is a resource consuming and challenging task. This paper proposes a methodology and system architecture for inference of electrical topology using process and model data from IEC 61850 compliant substation automation devices. A system of autonomous intelligent agents communicating via an overlay network is proposed where agents are capable of communicating on the IEC 61850 station bus. An algorithm for topology inference using structured exchange and comparison of process and model information is developed. The capabilities of structured information exchange and interfacing of substation automation devices enables plug-and-play operation of the topology inference requiring minimal prior knowledge of electrical network structure. Decentralized topology inference forms the basis for future work in operation and management of active distribution networks.
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25. |
- König, Johan, et al.
(author)
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Mapping the Substation Configuration Language of IEC 61850 to ArchiMate
- 2010
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In: Proceedings - IEEE International Enterprise Distributed Object Computing Workshop, EDOC. - : IEEE. - 9780769541648 ; , s. 60-68
-
Conference paper (peer-reviewed)abstract
- This paper presents a mapping between the Enterprise Architecture framework ArchiMate and the Substation Configuration Language (SCL) of IEC 61850. Enterprise Architecture (EA) is a discipline for managing an enterprise's information system portfolio in relation to the supported business. Metamodels, descriptive models on how to model and one of the core components of EA, can assist stakeholders in many ways, for example in decision-making. Moreover, the power industry is a domain with an augmented reliance on the support of information systems. IEC 61850 is a standard for the design of Substation Automation (SA) systems and provides a vendor independent framework for interoperability by defining communication networks and functions. The SCL is a descriptive language in IEC 61850 on the configuration of substation Intelligent Electronic Devices (IED) which describes the structure together with physical components and their relating functions. By using SCL, which models the architecture of SA systems, and mapping it to ArchiMate, stakeholders are assisted in understanding their SA system and its architecture. The mapping is intended to support the integration of SA systems applying IEC 61850 into the enterprise architecture. The mapping is demonstrated with an example applying the mapping to a SA configuration based on SCL.
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26. |
- Liu, Ching-Ti, et al.
(author)
-
Assessment of gene-by-sex interaction effect on bone mineral density
- 2012
-
In: Journal of Bone and Mineral Research. - : Wiley. - 1523-4681 .- 0884-0431. ; 27:10, s. 2051-2064
-
Journal article (peer-reviewed)abstract
- Sexual dimorphism in various bone phenotypes, including bone mineral density (BMD), is widely observed; however, the extent to which genes explain these sex differences is unclear. To identify variants with different effects by sex, we examined gene-by-sex autosomal interactions genome-wide, and performed expression quantitative trait loci (eQTL) analysis and bioinformatics network analysis. We conducted an autosomal genome-wide meta-analysis of gene-by-sex interaction on lumbar spine (LS) and femoral neck (FN) BMD in 25,353 individuals from 8 cohorts. In a second stage, we followed up the 12 top single-nucleotide polymorphisms (SNPs; p?
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27. |
- Moayyeri, Alireza, et al.
(author)
-
Genetic determinants of heel bone properties : genome-wide association meta-analysis and replication in the GEFOS/GENOMOS consortium
- 2014
-
In: Human Molecular Genetics. - : Oxford University Press (OUP). - 0964-6906 .- 1460-2083. ; 23:11, s. 3054-3068
-
Journal article (peer-reviewed)abstract
- Quantitative ultrasound of the heel captures heel bone properties that independently predict fracture risk and, with bone mineral density (BMD) assessed by X-ray (DXA), may be convenient alternatives for evaluating osteoporosis and fracture risk. We performed a meta-analysis of genome-wide association (GWA) studies to assess the genetic determinants of heel broadband ultrasound attenuation (BUA; n = 14 260), velocity of sound (VOS; n = 15 514) and BMD (n = 4566) in 13 discovery cohorts. Independent replication involved seven cohorts with GWA data (in silico n = 11 452) and new genotyping in 15 cohorts (de novo n = 24 902). In combined random effects, meta-analysis of the discovery and replication cohorts, nine single nucleotide polymorphisms (SNPs) had genome-wide significant (P < 5 x 10(-8)) associations with heel bone properties. Alongside SNPs within or near previously identified osteoporosis susceptibility genes including ESR1 (6q25.1: rs4869739, rs3020331, rs2982552), SPTBN1 (2p16.2: rs11898505), RSPO3 (6q22.33: rs7741021), WNT16 (7q31.31: rs2908007), DKK1 (10q21.1: rs7902708) and GPATCH1 (19q13.11: rs10416265), we identified a new locus on chromosome 11q14.2 (rs597319 close to TMEM135, a gene recently linked to osteoblastogenesis and longevity) significantly associated with both BUA and VOS (P < 8.23 x 10(-14)). In meta-analyses involving 25 cohorts with up to 14 985 fracture cases, six of 10 SNPs associated with heel bone properties at P < 5 x 10(-6) also had the expected direction of association with any fracture (P < 0.05), including three SNPs with P < 0.005: 6q22.33 (rs7741021), 7q31.31 (rs2908007) and 10q21.1 (rs7902708). In conclusion, this GWA study reveals the effect of several genes common to central DXA-derived BMD and heel ultrasound/DXA measures and points to a new genetic locus with potential implications for better understanding of osteoporosis pathophysiology.
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28. |
- Nordström, Lars, et al.
(author)
-
A Multi-Disciplinary Course Portfolio on Computer Applications in Power Systems
- 2014
-
In: IEEE Transactions on Power Systems. - 0885-8950 .- 1558-0679. ; 29:4, s. 1919-1927
-
Journal article (peer-reviewed)abstract
- As a response to the new requirements posed by the shift towards Smartgrids, there have been many initiatives worldwide to develop and update power engineering education curricula. This paper reports efforts to develop courses with the purpose to cross the gap between the disciplines of power engineering and information communication technology at KTH-the Royal Institute of Technology in Sweden. The course portfolio is engineered to complement several master programs offered by the university, and the intended audience are students and practitioners both with and without the power engineering background. This paper primarily focuses on details of a keystone course, Computer Applications in Power Systems, and its connection with the other courses in the portfolio. To prove the popularity and relevance of the reported course portfolio, increasingly positive feedback from students, recognition from industry partners, and accomplishments in terms of meeting several strategic goals in education set by the IEEE Power & Energy Society are also reported by this paper.
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29. |
- Nordström, Lars, et al.
(author)
-
Information and communication system architectures for wide-area monitoring and control applications
- 2011
-
Conference paper (peer-reviewed)abstract
- This paper presents a review of work performed in the field of communication systems requirements for wide area monitoring and control applications. This includes studies performed both in the context of NASPI, the North American Syncrophasor Initiative, as well as other studies in the US and Europe. Presently a relatively large body of work has been done regarding the requirements on the communication infrastructure. Among the work included, are surveys among Transmission System Operators on the foreseen communication requirements, as well as other theoretical studies on acceptable delays and other performance characteristics, such as data loss, that Wide Area Control applications put on the Information and Communication System. Much of the above referenced work still needs verification either though experimental work or through simulations. It is especially important to simulate large scale communication infrastructures that consider background traffic under different operational conditions in the power system, such as under disturbances. The paper is concluded with some remarks on future direction of work within the field.
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30. |
- Oei, Ling, et al.
(author)
-
A genome-wide copy number association study of osteoporotic fractures points to the 6p25.1 locus
- 2014
-
In: Journal of Medical Genetics. - : BMJ Publishing Group. - 0022-2593 .- 1468-6244. ; 51:2, s. 122-131
-
Journal article (peer-reviewed)abstract
- BACKGROUND: Osteoporosis is a systemic skeletal disease characterised by reduced bone mineral density and increased susceptibility to fracture; these traits are highly heritable. Both common and rare copy number variants (CNVs) potentially affect the function of genes and may influence disease risk.AIM: To identify CNVs associated with osteoporotic bone fracture risk.METHOD: We performed a genome-wide CNV association study in 5178 individuals from a prospective cohort in the Netherlands, including 809 osteoporotic fracture cases, and performed in silico lookups and de novo genotyping to replicate in several independent studies.RESULTS: A rare (population prevalence 0.14%, 95% CI 0.03% to 0.24%) 210 kb deletion located on chromosome 6p25.1 was associated with the risk of fracture (OR 32.58, 95% CI 3.95 to 1488.89; p=8.69×10(-5)). We performed an in silico meta-analysis in four studies with CNV microarray data and the association with fracture risk was replicated (OR 3.11, 95% CI 1.01 to 8.22; p=0.02). The prevalence of this deletion showed geographic diversity, being absent in additional samples from Australia, Canada, Poland, Iceland, Denmark, and Sweden, but present in the Netherlands (0.34%), Spain (0.33%), USA (0.23%), England (0.15%), Scotland (0.10%), and Ireland (0.06%), with insufficient evidence for association with fracture risk.CONCLUSIONS: These results suggest that deletions in the 6p25.1 locus may predispose to higher risk of fracture in a subset of populations of European origin; larger and geographically restricted studies will be needed to confirm this regional association. This is a first step towards the evaluation of the role of rare CNVs in osteoporosis.
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31. |
- Qian, Xukun, et al.
(author)
-
Structure stability of metal-organic framework MIL-53 (Al) in aqueous solutions
- 2013
-
In: International journal of hydrogen energy. - : Elsevier BV. - 0360-3199 .- 1879-3487. ; 38:36, s. 16710-16715
-
Journal article (peer-reviewed)abstract
- The structural stability of MIL-53 (Al) in different pH aqueous solutions from room temperature to 100 degrees C has been investigated. Experimental results show MIL-53 (Al) is stable and highly resistant to hydrolysis in neutral and acidic solutions. It can retain its crystallinity and permanent porosity without structural collapse. The good structure stability of MIL-53 (Al) to aqueous solutions is quite unusual among the MOFs. The nitrogen adsorption for the soaked frameworks show a typical type I isotherm. In basic aqueous solution, MIL-53 (Al) undergoes structure transformation.
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32. |
- Quinlan, Ronald A., et al.
(author)
-
Transfer of carbon nanosheet films to nongrowth, zero thermal budget substrates
- 2011
-
In: Journal of Vacuum Science & Technology B. - : American Vacuum Society. - 1071-1023 .- 1520-8567. ; 29:3, s. 030602-
-
Journal article (peer-reviewed)abstract
- Carbon-based nanostructures and materials have become a popular subject of research due to their unique thermal, mechanical, electrical, and optical properties. For example, the strong C-C bonds of graphene-based systems allow for excellent thermal conduction at room temperature and the conjugation of the sp(2) lattice enables extremely high electron mobility. However, the use of carbon nanostructures as a component in polymer composites, sensors, mirco-electro-mechanical systems, and both rigid and flexible electronics has been limited by several factors, including the incompatibility with standard photolithography techniques, the high temperatures required for the nanostructure growth, and the presence of-or complication-of removing noncarbon species. Here, the authors report on a novel method for the transfer of carbon nanosheets to a low or zero thermal budget substrate while maintaining their original morphology and electrical properties. Four-point probe measurements' post-transfer shows the retention of in-plane conductivity and scanning electron microscopy reveals the preservation of the original vertical morphology. Raman spectroscopy measurements confirm the retention of the graphitic structure of the post-transfer nanosheet film. This new transfer technique builds on the ability to conformally coat nanosheets while maintaining the original ultrahigh surface area morphology and the ability to fully incorporate nanosheets into several polymers while maintaining the original nanostructure separation. For a demonstration of the usefulness of polymer filling, carbon nanosheets were used as an ultrahigh surface area electrode for the photoactive polymer poly[2-methoxy-5-(2'-ethyl-hexyloxy)-1,4-phenylene vinylene] in proof of principle experiments of a nanosheet-based organic photovoltaic device.
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33. |
- Sampson, Joshua N., et al.
(author)
-
Analysis of Heritability and Shared Heritability Based on Genome-Wide Association Studies for 13 Cancer Types
- 2015
-
In: Journal of the National Cancer Institute. - : Oxford University Press (OUP). - 0027-8874 .- 1460-2105. ; 107:12
-
Journal article (peer-reviewed)abstract
- Background: Studies of related individuals have consistently demonstrated notable familial aggregation of cancer. We aim to estimate the heritability and genetic correlation attributable to the additive effects of common single-nucleotide polymorphisms (SNPs) for cancer at 13 anatomical sites. Methods: Between 2007 and 2014, the US National Cancer Institute has generated data from genome-wide association studies (GWAS) for 49 492 cancer case patients and 34 131 control patients. We apply novel mixed model methodology (GCTA) to this GWAS data to estimate the heritability of individual cancers, as well as the proportion of heritability attributable to cigarette smoking in smoking-related cancers, and the genetic correlation between pairs of cancers. Results: GWAS heritability was statistically significant at nearly all sites, with the estimates of array-based heritability, h(l)(2), on the liability threshold (LT) scale ranging from 0.05 to 0.38. Estimating the combined heritability of multiple smoking characteristics, we calculate that at least 24% (95% confidence interval [CI] = 14% to 37%) and 7% (95% CI = 4% to 11%) of the heritability for lung and bladder cancer, respectively, can be attributed to genetic determinants of smoking. Most pairs of cancers studied did not show evidence of strong genetic correlation. We found only four pairs of cancers with marginally statistically significant correlations, specifically kidney and testes (rho = 0.73, SE = 0.28), diffuse large B-cell lymphoma (DLBCL) and pediatric osteosarcoma (rho = 0.53, SE = 0.21), DLBCL and chronic lymphocytic leukemia (CLL) (rho = 0.51, SE = 0.18), and bladder and lung (rho = 0.35, SE = 0.14). Correlation analysis also indicates that the genetic architecture of lung cancer differs between a smoking population of European ancestry and a nonsmoking Asian population, allowing for the possibility that the genetic etiology for the same disease can vary by population and environmental exposures. Conclusion: Our results provide important insights into the genetic architecture of cancers and suggest new avenues for investigation.
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34. |
- Sandels, Claes, et al.
(author)
-
Analyzing fundamental aggregation functions in power systems
- 2011
-
In: IEEE PES Innovative. Smart Grid Technol. Conf. Europe. - : IEEE. - 9781457714214
-
Conference paper (peer-reviewed)abstract
- The concept of Aggregators is receiving large attention when new business cases for Smart grids are presented. Several studies propose different schemes of aggregating load and/or production. However, many of these studies are tailored for one specific market or network, making the generic value of the work small. The objective of the work presented in the paper is to analyze the fundamental needs for aggregating small scale loads or production units from a technical, financial and regulatory point of view. The final results of the analysis can work as a foundation for developing more elaborate aggregation business cases. These can later be analyzed from a technical and economical standpoint by, e.g., simulations.
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35. |
- Tian, Yu, et al.
(author)
-
Revealing morphology rules of MX precipitates in Ti-V-Nb multi-microalloyed steels
- 2022
-
In: Materials Characterization. - : Elsevier BV. - 1044-5803 .- 1873-4189. ; 188
-
Journal article (peer-reviewed)abstract
- Despite a large number of studies relevant to MX (M = Ti, V, Nb; X = C, N) precipitation in microalloyed steels, the evolution rules of the precipitate morphology remain unclear. In this work, the precipitation behavior and morphological characteristics of MX precipitates in deformed Ti-V-Nb multi-microalloyed steels under contin-uous cooling were revealed through integrating transmission electron microscopy and theoretical models. The experimental results demonstrate that the precipitates are mainly Ti-rich cuboidal multi-component precipitates and irregular compound precipitates formed in austenite, and fine spherical V8C7 precipitates formed in ferrite. For the first time, the L parameter model that evaluates the shape of MX precipitates has been introduced into microalloyed steels, together with the validating experiments. In austenite, as the L increases, precipitates tend to become cuboidal under equilibrium conditions while rod-like elongating along their (100) orientation under deformation conditions; in ferrite, as the L increases, precipitates tend to be disk-like under equilibrium con-ditions while thin elliptical cylindrical extending along their (110) orientation on the habit plane under defor-mation conditions. The evolution rules of precipitate morphology revealed in this work provide insights in controlling precipitates morphology to develop high-performance microalloyed steels.
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36. |
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37. |
- Wang, Yu, et al.
(author)
-
FlexZNS : Building High-Performance ZNS SSDs with Size-Flexible and Parity-Protected Zones
- 2023
-
In: Proceedings - 2023 IEEE 41st International Conference on Computer Design, ICCD 2023. - : Institute of Electrical and Electronics Engineers (IEEE). ; , s. 291-299
-
Conference paper (peer-reviewed)abstract
- NVMe zoned namespace (ZNS) SSDs present a new class of storage devices with attractive features including low cost, software definability, and stable performance. However, one primary culprit that hinders the adoption of ZNS is the high garbage collection (GC) overhead it brings to host software. The ZNS interface divides the logical address space into size-fixed zones that must be written sequentially. Despite being friendly to flash memory, ZNS requires host software to perform out-of-place updates and GC on individual zones. Current ZNS SSDs typically employ a large zone size (e.g., of GBs) to be conducive to die-level RAID protection on flash memory. This impedes flexible data placement, such as mixing data with different lifetimes in the same zone, and incurs sizable data migrations during zone GC. To address this problem, we propose FlexZNS, a novel ZNS SSD design that provides reliable zoned storage allowing host software to configure the zone size flexibly as well as multiple zone sizes. The size variability of zones poses two interrelated challenges, one for the SSD controller to establish per-zone RAID protection, and the other for host software to manage variable zone capacity loss caused by parity storage. To tackle the challenges, FlexZNS decouples the storage of parity from individual zones on flash memory and hides the zone capacity loss from the host software. We verify FlexZNS on a ZNS-compatible file system F2FS and a popular key-value store RocksDB. Extensive experiments demonstrate that FlexZNS can significantly improve the system performance and reduce GC-induced write amplification, compared with a conventional ZNS SSD with large-sized zones.
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38. |
- Woo, Jong Hun, et al.
(author)
-
Assessment Framework of Smart Shipyard Maturity Level via Data Envelopment Analysis
- 2021
-
In: Sustainability. - : MDPI AG. - 2071-1050. ; 13:4
-
Journal article (peer-reviewed)abstract
- The fourth industrial revolution ("Industry 4.0") has caused an escalating need for smart technologies in manufacturing industries. Companies are examining various cutting-edge technologies to realize smart manufacturing and construct smart factories and are devoting efforts to improve their maturity level. However, productivity improvement is rarely achieved because of the large variety of new technologies and their wide range of applications; thus, elaborately setting improvement goals and plans are seldom accomplished. Fortunately, many researchers have presented guidelines for diagnosing the smartness maturity level and systematic directions to improve it, for the eventual improvement of productivity. However, most research has focused on mass production industries wherein the overall smartness maturity level is already high (e.g., high-level automation). These studies thus have limited applicability to the shipbuilding industry, which is basically a built-to-order industry. In this study, through a technical demand survey of the shipbuilding industry and an investigation of existing smart manufacturing and smart factories, the keywords of connectivity, automation, and intelligence were derived and based on these keywords, we developed a new diagnostic framework for smart shipyard maturity level assessment. The framework was applied to eight shipyards in South Korea to diagnose their smartness maturity level, and a data envelopment analysis (DEA) was performed to confirm the usefulness of the diagnosis results. By comparing the DEA models, the results with the smart level as an input represents the actual efficiency of shipyards better than the results of conventional models.
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39. |
- Wu, Renbing, et al.
(author)
-
Pt nanodendrites anchored on bamboo-shaped carbon nanofiber arrays as highly efficient electrocatalyst for oxygen reduction reaction
- 2013
-
In: International journal of hydrogen energy. - : Elsevier BV. - 0360-3199 .- 1879-3487. ; 38:36, s. 16677-16684
-
Journal article (peer-reviewed)abstract
- In order to improve the Pt utilization and enhance their catalytic performance in fuel cells, a novel composite electrode composed of single-crystalline Pt nanodendrites and support constructed by bamboo-shaped carbon nanofiber arrays (CNFAs) on carbon paper, is reported. This electrode is designed by growing vertically CNFAs on carbon paper via plasma enhanced chemical vapor deposition, followed by the direct synthesis of Pt nanodendrites using a simple surfactant-free aqueous solution method. Electron microscopy studies reveal that the Pt nanodendrites are uniformly high dispersed and anchored on the surface of CNFAs. Electrochemical measurements demonstrate that the resultant electrode exhibits higher electrocatalytic activity and stability for oxygen reduction reaction than commercial Pt/C catalyst, suggesting its potential application in fuel cells.
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40. |
- Wu, Yiming, 1987-, et al.
(author)
-
Framework incorporating synchronized phasor data for power system operation and control
- 2012
-
In: The 9th IET International Conference on Advances in Power System Control, Operation and Management. - : Institution of Engineering and Technology. - 9781849197434
-
Conference paper (peer-reviewed)abstract
- This position paper presents initial research and investigation on a unified framework combining two independent systems, the legacy SCADA system and the synchronized phasor data system, that share the same measurement sources, i.e., current and voltage transducers and the same communication medium. In this framework, conventional SCADA system coupled with substation automation system are modeled together with synchronized phasor systems. The contribution of this paper also includes a state-of–the-art survey of topics related to the proposed architectures. Furthermore, an overview of the data flows between substation and control centers including both SCADA and phasor measurements are presented. Taking into consideration the growing interest in communication and automation standardization this paper also addresses the communication between the substations coupled with relevant standards and technology.
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41. |
- Wu, Yiming, 1987-, et al.
(author)
-
Perspectives on Peer-to-Peer Data Delivery Architectures for Next Generation Power Systems
- 2013
-
In: Smart Grid Management.
-
Conference paper (peer-reviewed)abstract
- Introduction of new Information and Communication Technologies (ICT) and aggregation of equipment bring in new perspectives in terms of the increasing number of data users. It also brings new data delivery requirements which are difficult to be met by the legacy systems. Off-the-shelf standards and communication technologies are the enablers to push current data delivery solutions to a new level. At this level this new data delivery system can fulfill Quality of Service (QoS) requirements of next generation power system. This paper proposes a comprehensive architecture of Peer-to-Peer (P2P) based overlay-control data delivery system covering all levels of data delivery. The core technology of such an architecture lays on the Intelligent Substation Gateway (ISG), which is employed to provide data delivery service to meet the QoS requirements. Proposed data delivery system brings advantages as autonomy, flexibility, scalability, and efficient to the power system.
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42. |
- Xie, M., et al.
(author)
-
A seasonal ARIMA model with exogenous variables for elspot electricity prices in Sweden
- 2013
-
In: European Energy Market (EEM), 2013 10th International Conference on the. - : IEEE. - 9781479920082 ; , s. 6607293-
-
Conference paper (peer-reviewed)abstract
- In a spot market, price prediction plays an indispensable role in maximizing the benefit of a producer as well as optimizing the utility of a consumer. This paper develops a seasonal ARIMA model with exogenous variables (SARIMAX) to predict day-ahead electricity prices in Elspot market, the largest day-ahead market for power trading in the world. Compared with the basic ARIMA model, SARIMAX has two distinct features: 1) A seasonal component is introduced to cope with weekly effect on price fluctuations. 2) Exogenous variables that exert influence on electricity prices are incorporated to make price predictions in the context of an integrated energy market. A detailed implementation of SARIMAX for Elspot market in Sweden is presented.
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43. |
- Ye, Chenhui, et al.
(author)
-
All-Optical Approach to Microwave Frequency Measurement With Large Spectral Range and High Accuracy
- 2012
-
In: IEEE Photonics Technology Letters. - : IEEE. - 1041-1135 .- 1941-0174. ; 24:7, s. 614-616
-
Journal article (peer-reviewed)abstract
- An all-optical approach for microwave frequency (MWF) measurement with a low-speed oscilloscope is proposed and experimentally demonstrated. In this scheme, an optical filter with a single and ultranarrow passband, together with a tunable laser and a low-speed photodiode is utilized to calculate the MWF by measuring the time delay between the sweeping optical carrier and its upper/lower sideband passing through the filter. Single-frequency and multifrequency measurements are experimentally demonstrated. The measurement recognition, accuracy, and resolution are below 0.1, 0.09, and 0.2 GHz, respectively. This proposed scheme can be easily upgraded to higher frequencies using a modulator with higher bandwidth proportional to the desired measurement range.
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44. |
- Ye, Chenhui, et al.
(author)
-
An All-Optical Transformer From Differential NRZ Data to Ultra-Wideband Pulse Stream
- 2011
-
In: IEEE Photonics Technology Letters. - 1041-1135 .- 1941-0174. ; 23:9, s. 579-581
-
Journal article (peer-reviewed)abstract
- We propose and experimentally demonstrate a compact and cost-effective scheme based on a fiber Sagnac structure to realize real time conversion from differential nonreturn-to-zero (NRZ) data to ultra-wideband (UWB) pulse stream. The proposed conversion system for the UWB signal generation consists of a single-wavelength laser, a phase modulator, several polarization controllers, and optical couplers. Due to the optical interference between the two phase-modulated light waves with slight phase difference in the Sagnac loop, two sharp optical pulses with opposite polarities are obtained. With proper time delay, a UWB monocycle pulse stream is generated from the original differential NRZ data. Our proposed method gives a reliable, easy, and low-cost transformer from differential NRZ signal to UWB pulse stream, and no high-speed arbitrary waveform generator (AWG) is required in this all-optical transformer.
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45. |
- Zhang, Shuai, et al.
(author)
-
MIMO reference antennas for OTA applications
- 2013
-
In: 2013 7th European Conference on Antennas and Propagation, EuCAP 2013. - New York : IEEE. - 9788890701832 ; , s. 2556-2557, s. 2243-2244
-
Conference paper (peer-reviewed)abstract
- In this paper, MIMO reference antennas with different correlation coefficients are proposed for Over-The-Air (OTA) applications. The correlation can be simply controlled through a slot etched on a dual-feed PIFA with the similar total efficiency. Three kinds of situations are investigated with the proposed method: high correlation (HC), mid correlation (MC), and low correlation (LC). In order to verify the introduced idea, the measurements of correlations and efficiencies are carried out in a reverberation chamber. The simulation and measurement agree well with each other.
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46. |
- Zhang, Shuai, et al.
(author)
-
MIMO Reference Antennas with Controllable Correlations and Total Efficiencies
- 2014
-
In: Progress In Electromagnetics Research. - 1070-4698 .- 1559-8985. ; 145, s. 115-121
-
Journal article (peer-reviewed)abstract
- MIMO reference antennas are proposed for over the air (OTA) measurement applications. The reference antennas could get rid of feeding cable interference and control envelope correlation coefficients (ECC) continuously by only changing the length of an etched slot on a dual-feed PIFA. If only the ECC is investigated, the MIMO reference antenna is optimized to have a small variation of total efficiency from 70% to 50% when the ECC increases from 0.1 to 0.88. The prototypes are fabricated and measured in a scattered field chamber (SFC). Measurements agree well with the simulations. If the MIMO performance is studied, the MIMO reference antenna is proposed to own a large variation of total efficiencies from 90% to 47% while the ECC increases from 0 to 0.98. The bandwidth of the proposed reference antennas depend on the size of the antennas. This method is valid for all the frequencies.
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47. |
- Zhang, S. W., et al.
(author)
-
Synthesis of narrowly distributed polystyrene-encapsulated silica nanoparticles via emulsion polymerization
- 2017
-
In: Journal of Dispersion Science and Technology. - : Informa UK Limited. - 0193-2691 .- 1532-2351. ; 38:3, s. 451-456
-
Journal article (peer-reviewed)abstract
- Polystyrene (PS)-encapsulated silica nanoparticles were successfully synthesized by conventional emulsion polymerization for solving the aggregation matter of nanoscaled silica. The grafting coupling agents and PS on the silica surface were detected by Fourier Transform Infrared (FTIR) spectroscopy. The influence of silica and monomer to water ratios and initiator concentration on particle size distribution of the nanocomposite latex was investigated. The particle size distribution firstly narrowed and then broadened with the increase of silica and monomer to water ratios and initiator concentration. The narrow distribution could be controlled in an appropriate silica and monomer to water ratio and an initiator concentration of 1/15 and 2wt%, respectively. From the evaluation of transmission electron microscopy (TEM) micrographs and dynamic light scattering (DLS) measurement, it was proved that the nanocomposite latex did not have all sphere-like shape, but contained tiny amounts of irregular bodies. The formation mechanism of PS-encapsulated silica nanoparticles was also discussed.
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48. |
- Zhou, Yongqiang, et al.
(author)
-
Inflow rate-driven changes in the composition and dynamics of chromophoric dissolved organic matter in a large drinking water lake
- 2016
-
In: Water Research. - : Elsevier BV. - 0043-1354 .- 1879-2448. ; 100, s. 211-221
-
Journal article (peer-reviewed)abstract
- Drinking water lakes are threatened globally and therefore in need of protection. To date, few studies have been carried out to investigate how the composition and dynamics of chromophoric dissolved organic matter (CDOM) in drinking water lakes are influenced by inflow rate. Such CDOM can lead to unpleasant taste and odor of the water and produce undesirable disinfection byproducts during drinking water treatment. We studied the drinking water Lake Qiandao, China, and found that the concentrations of suspended particulate matter (SPM) in the lake increased significantly with inflow rate (p
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49. |
- Zhou, Yongqiang, et al.
(author)
-
Rainstorm events shift the molecular composition and export of dissolved organic matter in a large drinking water reservoir in China : High frequency buoys and field observations
- 2020
-
In: Water Research. - : Elsevier BV. - 0043-1354 .- 1879-2448. ; 187
-
Journal article (peer-reviewed)abstract
- Rainstorm events can flush large amounts of terrestrial organic-rich material into lakes that are used for drinking water. To date, few studies have been carried out to investigate how rainstorm events change the molecular composition, bio-lability, and flux of upstream-imported dissolved organic matter (DOM), which can impact the odor and taste of drinking water as well as the efficiency of wastewater treatment. We undertook high-frequency buoy monitoring and point sample collection (n = 495), during high, moderate, and low inflow discharge, in Lake Qiandao, a key drinking water source for about 10 million people. Data from two online fluorescent DOM sensors deployed and field samples collected at the river site, Jiekou, and the lake site, Xiaojinshan, showed that rainstorm events increased the specific UV absorbance (SUVA254), humification index (HIX), humic-like components (C1-C2), and FT-ICR MS derived condensed aromatic and polyphenolic compounds (p < 0.001) and decreased the spectral slope of DOM (S275–295), spectral slope ratio (SR), biological index (BIX), and highly bio-degradable peptide-like and aliphatic substances (p < 0.001). Our results suggest that rainstorm events enhanced the export to the lake of colored, hydrophobic, and aromatic DOM. Upstream-derived dissolved organic carbon (DOC) concentrations decreased (p < 0.001), while DOC bio-availability (BDOC) increased only slightly (p < 0.05) during rainstorm events. The loss rate of DOC in Lake Qiandao is 0.82 × 104 t C yr−1, of which 0.30 × 104 t C yr−1 is highly bio-labile, and higher occurrences of both ≥ 25 mm d − 1 and ≥ 50 mm d − 1 rainfall events are anticipated by linear fittings for this region in the future. The application of in situ fluorescence sensors provides an early warning of DOC surge incidents caused by rainstorm events and may be useful in advising drinking water treatment plant managers of changes in raw water DOM quality and treatability.
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50. |
- Zhu, Jie, 1990, et al.
(author)
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Bi-level ramp merging coordination for dense mixed traffic conditions
- 2024
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In: Fundamental Research. - 2096-9457 .- 2667-3258. ; In Press
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Journal article (peer-reviewed)abstract
- Connected and Autonomous Vehicles (CAVs) hold great potential to improve traffic efficiency, emissions and safety in freeway on-ramp bottlenecks through coordination between mainstream and on-ramp vehicles. This study proposes a bi-level coordination strategy for freeway on-ramp merging of mixed traffic consisting of CAVs and human-driven vehicles (HDVs) to optimize the overall traffic efficiency and safety in congested traffic scenarios at the traffic flow level instead of platoon levels. The macro level employs an optimization model based on fundamental diagrams and shock wave theories to make optimal coordination decisions, including optimal minimum merging platoon size to trigger merging coordination and optimal coordination speed, based on macroscopic traffic state in mainline and ramp (i.e., traffic volume and penetration rates of CAVs). Furthermore, the micro level determines the real platoon size in each merging cycle as per random arrival patterns and designs the coordinated trajectories of the mainline facilitating vehicle and ramp platoon. A receding horizon scheme is implemented to accommodate human drivers’ stochastics as well. The developed bi-level strategy is tested in terms of improving efficiency and safety in a simulation-based case study under various traffic volumes and CAV penetration rates. The results show the proposed coordination addresses the uncertainties in mixed traffic as expected and substantially improves ramp merging operation in terms of merging efficiency and traffic robustness, and reducing collision risk and emissions, especially under high traffic volume conditions.
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