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排序方式: 共有191条查询结果,搜索用时 234 毫秒
1.
Bossert R.C. Brandt J.S. Carson J.A. Coulter K. Delchamps S. Ewald K. Fulton H. Gonczy I. Koska W. Lamm M.J. Strait J.B. Wake M. Gordon M. Hassan N. Sims R. Winters M. 《IEEE transactions on magnetics》1992,28(1):129-132
Full length and short model SSC (Superconducting Super Collider) 50 mm bore dipoles are being built and tested at Fermilab. The mechanical design of these magnets has been determined from experience with the construction of previous superconducting magnets. Construction experience includes coil fabrication, ground insulation, instrumentation, collaring, and yoke assembly. Fabrication techniques are explained, and construction problems and their solutions are reviewed. The relationship of short to long model construction is discussed 相似文献
2.
Khanapure Sharanabasappa Pore Dattaprasad Jagadale Megha Patil Vaishali Rashinkar Gajanan 《Catalysis Letters》2021,151(8):2237-2249
Catalysis Letters - A novel silica supported ferrocene appended N-heterocyclic carbene-palladium complex (SilFemBenzNHC@Pd) has been prepared and characterized by using fourier transform infrared... 相似文献
3.
Brian Coulter Srini Krishnamoorthy 《International Transactions in Operational Research》2014,21(2):263-274
This paper examines the effect of reference prices on companies operating within competitive industries. We confirm that even with competition, firms optimally price high in the short term to generate a high reference price and then decrease this price over time. Competitors' prices converge toward each other over time, emphasizing the short‐term nature of reference prices. We then show that pricing optimally to take advantage of reference prices generates a positive externality for other firms in an industry, such that competitors may generate higher profit. The longer the focus of a given firm, the more profit the firm generates, but less relative to its competitors. This arises because the externalities created through pricing high to increase reference prices outweigh the benefits of the higher reference prices themselves. If pricing managers are compensated relative to their competition, this suggests that short‐termism may be implicitly encouraged to the detriment of profit. 相似文献
4.
L. Civale B. Maiorov A. Serquis J. O. Willis J. Y. Coulter H. Wang Q. X. Jia P. N. Arendt M. Jaime J. L. MacManus-Driscoll M. P. Maley S. R. Foltyn 《Journal of Low Temperature Physics》2004,135(1-2):87-98
The main challenges for the success of high temperature superconducting wires, the YBa2Cu3O7 (YBCO) coated conductors (CC), are to avoid the the weak-link problem through the production of biaxially textured films, and to increase the critical current density (J c) through the introduction of large densities of appropriate defects. To that end, it is essential to understand the pinning mechanisms and their correlation with the microstructure of the CC. We first present a brief overview of the main methods currently used to produce YBCO CC, and we describe the architecture of the YBCO on IBAD fabricated at Los Alamos, summarizing the recent improvements of their structural and superconducting properties. Then, we analyze some aspects of the J c dependence on temperature and magnetic field (orientation and intensity) for the best CC available, and we compare and contrast the results with those of YBCO thin films on single crystal substrates, in order to determine if the defects controlling the pinning mechanisms are the same in both cases. Our results indicate that over large field and angular ranges J c on CC is higher than J c in thin films on SCS. 相似文献
5.
Douglas A. Stow Christopher D. Lippitt Lloyd L. Coulter Andrew C. Loerch 《International journal of remote sensing》2018,39(5):1441-1458
The objective of this article is to synthesize research findings and requirements pertaining to development of time-sensitive remote-sensing systems (TSRSS) that support decision-making pertaining to post-hazard assessment of damage to what we define as hyper-critical infrastructure (HCI), based on an aerial imaging approach known as repeat station imaging (RSI). The following TSRSS components are addressed and related findings are reported: (1) understanding information requirements of emergency managers pertaining to damage of HCI; (2) flight planning and data capture requirements for supporting bi-temporal RSI pairs; (3) automatic image registration and shadow classification and normalization routines applied to RSI pairs; (4) damage detection and delineation approach that exploits simple temporal differences in image brightness to automatically, reliably, and robustly delineates new cracks associated with damage; and (5) rapid data and information transfer to emergency managers. The highest priority follow-on research topics are: (1) integrating small unmanned aerial systems (sUAS) with the RSI approach, while enabling multiple view perspectives other than vertical (i.e. nadir pointing) and (2) developing and testing of machine learning routines for automatic identification of damage features from RSI pairs, particularly those captured from integrated sUAS–RSI. 相似文献
6.
This paper presents a geocast technique for underwater sensor networks. The model named as Routing and Multicast Tree based Geocasting (RMTG) (TRACE'10, Bhopal, India, 2010; ICWET'10, Mumbai, India, 2010) has been designed for underwater sensor networks. In our previous work (TRACE'10, Bhopal, India, 2010; ICWET'10, Mumbai, India, 2010) we proposed only a theoretical model for underwater geocasting. The RMTG technique uses greedy forwarding and previous hop handshaking to route the packets towards the geocast region and further disseminates the data within the geocast region by creating a multicast shortest path tree. We also presented various link broken scenarios along with their solutions. The proposed model does not use the flooding technique to deliver the packets inside the geocast region that is used in most of the geocasting techniques. In this paper, we present the simulated RMTG model. The simulation results show that the proposed model provides an efficient distribution of data in the geocast region in terms of node mobility handling, packet delivery ratio and a better end‐to‐end latency. Most of the work on geocasting has been done for mobile and vehicular ad hoc networks; hence we present in this paper a novel simulated model for underwater environment. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
7.
8.
Brajendra Kumar Singh Jeremy Coulter Mohammad Abdul Ghani Sayani Syed M. Sami Mohammad Khalid Kemal E. Tepe 《The International journal of environmental studies》2013,70(5):765-776
Communication systems are needed to integrate generated power from wind farms with the electrical grid. This paper provides a comprehensive review of available communication technologies, protocols and objectives related to wind energy and electrical grid integration. This paper summarizes the communication system solutions for wind generation. A major obstacle is an absence of unified communication architectures and standards. 相似文献
9.
Cover Feature: A Designed Enzyme Promotes Selective Post‐translational Acylation (ChemBioChem 15/2018)
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10.
Previous studies in the primate fetal adrenal gland have indicated that the gland is comprised of three functional zones: 1) the inner fetal zone (FZ), which has the enzymes necessary for dehydroepiandrosterone sulfate (DHEAS) production beginning early in gestation; 2) the transitional zone (TZ), which possesses enzymes necessary for cortisol production; and 3) the outer, definitive zone (DZ), which appears to function as a reservoir of progenitor cells that may populate the remainder of the gland and does not acquire a steroidogenic phenotype with the capacity to produce mineralocorticoids until near term. The enzymes CYP21A2 (P450 21 hydroxylase, or P450c21), CYP11B1 (11beta hydroxylase or P450c11) and CYP11B2 (aldosterone synthase) are necessary for glucocorticoid and mineralocorticoid synthesis but have not been localized previously in an ontogenic manner in the primate fetal adrenal gland. Therefore, we used immunocytochemistry (ICC) to assess specific zonal localization and developmental regulation of CYP21A2 and CYP11B1/CYP11B2 in the human (13-24 weeks' gestation) and rhesus monkey (109 d-term) fetal adrenal gland. In the fetal rhesus, ICC was performed with and without metyrapone administration to the fetus to assess the effects of endogenously increased fetal ACTH. In the human fetal adrenal, CYP21A2 immunoreactivity (IR) was present in only a few isolated cells in the DZ but was detectable in almost all cells in the TZ and FZ. In the fetal rhesus, CYP21A2-IR was present in cells throughout the DZ and TZ and, to a lesser degree, in the FZ. Staining intensity increased with advancing gestational age and was up-regulated in the DZ and TZ, but not the FZ, of the metyrapone-treated fetuses. In the human fetal adrenal gland, CYP11B1/CYP11B2-IR was absent in the DZ but present in the TZ and FZ. In the fetal rhesus monkey adrenal, CYP11B1/CYP11B2-IR was present in all cells of the TZ and FZ but was absent from the DZ until near term. After metyrapone, CYP11B1/CYP11B2-IR was induced in the DZ and was up-regulated in the TZ and FZ. Taken together, these data indicate that in the primate fetal adrenal gland, the FZ has the capacity to synthesize DHEA and DHEAS beginning early in development, the TZ has the capacity to synthesize cortisol after midgestation, and the DZ has the capacity to synthesize mineralocorticoids, but not until near term. The spatial localization of steroid metabolizing enzymes and steroid products in the human and rhesus monkey fetal adrenal suggests analogies of the three functional zones of the fetus (DZ, TZ, and FZ) to their adult counterparts (zona glomerulosa, zona fasciculata, and zona reticularis) and their steroid products (mineralocorticoids, glucocorticoids and androgens, respectively), although the reason for the presence of CYP11B1/CYP11B2- and CYP21A2-IR in the FZ remains to be elucidated. 相似文献