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51.
A new type of left handed microstrip lines implemented by means of complementary split-ring resonators (CSRRs) is proposed. The CSRRs are etched on the signal strip alternating with series gaps. Additionally, shunt connected stubs are introduced for the first time to the previous structure. The combination of these three elements, that is, the series gaps, the CSRR and the shunt inductance, enhances design flexibility. By this means, the ground plane is left unaltered and narrow band artificial transmission lines with good performance and compact dimensions can be synthesised. The lumped element equivalent circuit model of the structure is proposed and validated. To demonstrate the applicability of these new left handed transmission lines, two compact microwave components have been designed and fabricated: (i) a narrow band power divider and (ii) a band pass filter. The resulting power divider is 75% smaller than the conventional implementation and 50% smaller than previous power dividers implemented by means of CSRRs. The band pass filter performance is comparable to that of previous CSRR-based filters with ground plane etching, whereas its size is smaller. This work represents a significant progress on the design of microwave components based on CSRRs, that is, the approach is opened to those systems where the ground plane cannot be etched. 相似文献
52.
Wanasinghe Arachchige Dumith Madushanka Jayathilaka Kun Qi Yanli Qin Amutha Chinnappan William Serrano‐García Chinnappan Baskar Hongbo Wang Jianxin He Shizhong Cui Sylvia W. Thomas Seeram Ramakrishna 《Advanced materials (Deerfield Beach, Fla.)》2019,31(7)
Together with the evolution of digital health care, the wearable electronics field has evolved rapidly during the past few years and is expected to be expanded even further within the first few years of the next decade. As the next stage of wearables is predicted to move toward integrated wearables, nanomaterials and nanocomposites are in the spotlight of the search for novel concepts for integration. In addition, the conversion of current devices and attachment‐based wearables into integrated technology may involve a significant size reduction while retaining their functional capabilities. Nanomaterial‐based wearable sensors have already marked their presence with a significant distinction while nanomaterial‐based wearable actuators are still at their embryonic stage. This review looks into the contribution of nanomaterials and nanocomposites to wearable technology with a focus on wearable sensors and actuators. 相似文献
53.
L. R. Gil A. Marques 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》1989,280(2-3):301-303
Curves of “range × cone length” and “diameter × cone length” are calculated for tracks left by low-energy light ions in 39Cr. The calculations cover ions from helium to iron and are performed for 6.25N NaOH at 70°C and a standard etching time but can be easily extended to other etching conditions. 相似文献
54.
Mateusz Sypniewski Zbigniew J. Krl Joanna Szyda Elbieta Kaja Magdalena Mroczek Tomasz Suchocki Adrian Lejman Maria Stpie Piotr Topolski Maciej Dbrowski Krzysztof Kotlarz Angelika Aplas Micha Wasiak Marzena Wojtaszewska Pawe Zawadzki Agnieszka Pawlak Robert Gil Paula Dobosz Joanna Stojak 《International journal of molecular sciences》2022,23(15)
Background: Severe outcomes of COVID-19 account for up to 15% of all cases. The study aims to check if any gene variants related to cardiovascular (CVD) and pulmonary diseases (PD) are correlated with a severe outcome of COVID-19 in a Polish cohort of COVID-19 patients. Methods: In this study, a subset of 747 samples from unrelated individuals collected across Poland in 2020 and 2021 was used and whole-genome sequencing was performed. Results: The GWAS analysis of SNPs and short indels located in genes related to CVD identified one variant significant in COVID-19 severe outcome in the HADHA gene, while for the PD gene panel, we found two significant variants in the DRC1 gene. In this study, both potentially protective and risk variants were identified, of which variants in the HADHA gene deserve the most attention. Conclusions: This is the first study reporting the association between the HADHA and DRC1 genetic variants and COVID-19 severe outcome based on the cohort WGS analysis. Although all the identified variants are localised in introns, they may be correlated and therefore inherited along with other risk variants, potentially causative to severe outcome of COVID-19 but not discovered yet. 相似文献
55.
Computational workflows are a powerful paradigm to represent and manage complex applications, particularly in large-scale distributed scientific data analysis. Workflows represent application components that result in individual computations as well as their interdependences in terms of dataflow. Workflow systems use these representations to manage various aspects of workflow creation and execution for users, such as the automatic assignment of execution resources. This article describes an approach to automating a new aspect of the process: the selection of application components and data sources. We present a novel approach that enables users to specify varying degrees of detail and amount of constraints in a workflow request, including the specification of constraints on input, intermediate or output data in the workflow, abstract workflow component classes rather than specific component implementations, and generic reusable workflow templates that express a pre-defined combination of components. The algorithm elaborates the user request into a set of fully ground workflows with specific choices of data sources and codes to be used so that they can be submitted for mapping and execution. The algorithm searches through the space of possible candidate workflows by creating increasingly more specialized versions of the original template and eliminating candidates that violate constraints cumulated in the candidate workflow as components and data sources are selected. A novel feature of our approach is that it assumes a distributed architecture where data and component catalogues are separate from the workflow system. The algorithm explicitly poses queries to external catalogues, and therefore any reasoning regarding data or component properties is not assumed to occur within the workflow system. We describe our implementation of this approach in the Wings workflow system. This implementation uses the W3C Web Ontology Language and associated reasoners to implement the workflow system as well as the data and component catalogues. This research demonstrates the use of artificial intelligence techniques to support the kinds of automation envisioned by the scientific community for large-scale distributed scientific data analysis. 相似文献
56.
Pia Fahlbusch Aleksandra Nikolic Sonja Hartwig Sylvia Jacob Ulrike Kettel Cornelia Kllmer Hadi Al-Hasani Stefan Lehr Dirk Müller-Wieland Birgit Knebel Jrg Kotzka 《International journal of molecular sciences》2022,23(12)
Alterations in mitochondrial function are an important control variable in the progression of metabolic dysfunction-associated fatty liver disease (MAFLD), while also noted by increased de novo lipogenesis (DNL) and hepatic insulin resistance. We hypothesized that the organization and function of a mitochondrial electron transport chain (ETC) in this pathologic condition is a consequence of shifted substrate availability. We addressed this question using a transgenic mouse model with increased hepatic insulin resistance and DNL due to constitutively active human SREBP-1c. The abundance of ETC complex subunits and components of key metabolic pathways are regulated in the liver of these animals. Further omics approaches combined with functional assays in isolated liver mitochondria and primary hepatocytes revealed that the SREBP-1c-forced fatty liver induced a substrate limitation for oxidative phosphorylation, inducing enhanced complex II activity. The observed increased expression of mitochondrial genes may have indicated a counteraction. In conclusion, a shift of available substrates directed toward activated DNL results in increased electron flows, mainly through complex II, to compensate for the increased energy demand of the cell. The reorganization of key compounds in energy metabolism observed in the SREBP-1c animal model might explain the initial increase in mitochondrial function observed in the early stages of human MAFLD. 相似文献
57.
An 800 kV electric power substation can have more than one hundred of porcelain multicone type insulators supporting busbar structures.Two or more sections in series,having middle and end fittings,compose these insulators.Ageing process can cause degradation of the cement used in this type of insulator and this fact can affect its dielectric performance under heavy rain.This paper presents results of an investigation based on power frequency high voltage tests performed on 800 kV porcelain multicone type insulators,removed from service after having operated for more than 20 years,as well a non-used one that had been stored on site for long time.The insulators were tested in different arrangements:each section at a time and the two sections assembled in series,as actually used insulator columns.The tests were carried out under artificial rain ranging from 1 mm/min to 5 mm/min.The results have confirmed a reduction of up to 30% in the insulator power frequency flashover voltage under 5 mm/min rain conditions and gave important information to the utility about radial cracks that were observed in many insulators and about the discharge mechanisms along the insulators under rain. 相似文献
58.
A major issue in the design and operation of ad hoc networks is sharing the common spectrum among links in the same geographic
area. Bandwidth allocation, to optimize the performance of networks in which each station can converse with at most a single
neighbor at a time, has been recently studied in the context of Bluetooth Personal Area Networks. There, centralized and distributed,
capacity assignment heuristics were developed, with applicability to a variety of ad hoc networks. Yet, no guarantees on the
performance of these heuristics have been provided. In this paper, we extend these heuristics such that they can operate with
general convex objective functions. Then, we present our analytic results regarding these heuristics. Specifically, we show
that they are β-approximation (β<2) algorithms. Moreover, we show that even though the distributed and centralized algorithms
allocate capacity in a different manner, both algorithms converge to the same results. Finally, we present numerical results
that demonstrate the performance of the algorithms.
Randeep Bhatia received the Ph.D. degree in Computer Science from University of Maryland, the M.S. degree in Mathematics and Computer Science
from University of Illinois at Chicago and the B.Tech. degree in Computer Science and Engineering from Indian Institute of
Technology, Delhi. He is currently with the High Speed Networks Research Department at Bell Labs, Lucent technologies, working
on network design, traffic engineering and scheduling algorithms. His current research interests are in the area of QoS for
multimedia services in wireless data networks.
Adrian Segall received the B.Sc. and M.Sc. degrees in electrical engineering from the Technion, Israel Institute of Technology in 1965
and 1971, respectively, and the Ph.D. degree in electrical engineering with a minor in statistics from Stanford University
in 1973. After serving active duty in the Israel Defense Forces, he joined in 1968 the Scientific Department of Israel’s Ministry
of Defense. From 1973 to 1974 he was a Research Engineer at System Control Inc., Palo Alto, CA and a Lecturer at Stanford
University. From 1974 to 1976 he was an Assistant Professor of Electrical Engineering and Computer Science at the Massachusetts
Institute of Technology. From 1987 to 1998 he was on the faculty of the Department of Computer Science at the Technion. He
is presently Benjamin Professor of Computer-Communication Networks in the Department of Electrical Engineering, Technion,
Israel Institute of Technology. From 1982 to 1984 he was on leave with the IBM T.J.Watson Research Center, Yorktown Heights,
NY. He held visiting positions with IBM, AT&T and Lucent Bell Labs. His current research interests are in the area of optical
networks, wireless, sensor and ad-hoc networks. Dr. Segall is an IEEE Fellow and has served in the past as Editor for Computer
Communication Theory of the IEEE Transactions on Communications, Editor for the IEEE Information Theory Society Newsletter
and Senior Editor for the IEEE Journal on Selected Areas in Communications. He was selected as an IEEE delegate to the 1975
IEEE-USSR Information Theory Workshop, and is the recipient of the 1981 Miriam and Ray Klein Award for Outstanding Research
and of the 1990 Taub Award in Computer Science.
Gil Zussman received the B.Sc. degree in Industrial Engineering and Management and the B.A. degree in Economics (both summa cum laude) from the Technion—Israel Institute of Technology in 1995. He received the M.Sc. degree (summa cum laude) in Operations Research from Tel-Aviv University in 1999 and the Ph.D. degree in Electrical Engineering from the Technion—Israel
Institute of Technology in 2004. Between 1995 and 1998, he served as an engineer in the Israel Defense Forces. He is currently
a Postdoctoral Associate in the Laboratory for Information and Decision Systems in MIT. His current research interests are
in the area of ad hoc and sensor networks. In particular, he is interested in energy efficient protocols, medium access control
protocols, and personal area networks. Gil received the Knesset (Israeli Parliament) Award for distinguished students, the
Best Student Paper Award at the IFIP-TC6 Networking 2002 Conference, and the IEEE Communications Magazine Best Paper Award
at the OPNETWORK 2002 Conference. In 2004 he received the Marie Curie Outgoing International Fellowship and the Fulbright
Fellowship. 相似文献
59.
Alvaro J. Romera Gil Levy Pierre C. Beukes Dave A. Clark Chris B. Glassey 《Nutrient Cycling in Agroecosystems》2012,92(3):329-346
On New Zealand dairy farms, it is the nitrogen excreted directly onto pasture, particularly urine, that drives nitrogen (N)
leaching from the farm. A new framework (UPF: Urine Patch Framework) is presented that post-processes the results of a whole
farm model and runs a mechanistic soil model to simulate the urine patches. Two alternative methods to simulate the spatial
distribution of urine patches were implemented and compared (Grid: spatially explicit, and Probabilistic: based on the probability of different temporal urination patterns). This paper describes the implementation of these two
methods in connection with a Whole Farm Model; and compares the N leaching predictions with observed data. Two examples are
provided, one analyzing the impact of urine patch overlap and another, the relative risk of N leaching at different times
of urinary N deposition. The model showed good correlation and predictive ability between simulated annual N leaching results
and observed data [R2 = 94 %, mean relative prediction error (MRPE) = 10 % for Grid and R2 = 72 %, MRPE = 20 % for Probabilistic]. The two methods produced similar results across an 8-year period for monthly and annual N leaching (R2 = 96 %, MRPE = 10 % and R2 = 86 %, MRPE = 8 %; respectively). Only 8 % of the paddock area was covered with multiple urinations during 1 year, but as
much as 39 % of the total urine volume was deposited on overlapped patches. Systematically removing all urinary N for 1 month
in either May or June reduced N leaching by approximately 20 %. Avoiding urinary N deposition during autumn or early winter
could be highly effective in mitigating N leached during the following winter. 相似文献
60.
Gustavo González‐Neves Graciela Gil Guzmán Favre Milka Ferrer 《International Journal of Food Science & Technology》2012,47(5):900-909
The anthocyanin composition of Tannat red wines obtained with four winemaking techniques was evaluated in different years. The wines were elaborated with traditional maceration (TM), cold pre‐fermentative maceration, delayed extraction of anthocyanins and extended maceration. Two vinifications were carried out for each technique, employing 70 kg of grapes in each one. The anthocyanin composition of wines was analysed by high‐performance liquid chromatography–diode array detection. The results confirm the fundamental role of the grape composition on the anthocyanin composition of the wines. The winemaking had an important effect on the total concentration of anthocyanins and also may modify the anthocyanic profile of wines. The wines obtained with TM had higher or similar content of anthocyanins than those elaborated with the other techniques. Canonical discriminant analysis of data showed that vintage has a greater effect on anthocyanin concentration than winemaking techniques. 相似文献