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1.
The review covers a number of works on heat pipes designed in the U.S.S.R. between 1970 and 1987, and consists of two parts. The first part deals with fundamental studies of energy and substance transfer in closed evaporator-condenser systems. The second one contains the results of integration of heat pipes, thermosyphons and units on their base in different branches of engineering, agriculture and building.  相似文献   

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Over the last 23 years, the U.S. Securities and Exchange Commission has required over 34,000 companies to file over 165,000 annual reports. These reports, the so-called “Form 10-Ks,” contain a characterization of a company’s financial performance and its risks, including the regulatory environment in which a company operates. In this paper, we analyze over 4.5 million references to U.S. Federal Acts and Agencies contained within these reports to measure the regulatory ecosystem, in which companies are organisms inhabiting a regulatory environment. While individuals across the political, economic, and academic world frequently refer to trends in this regulatory ecosystem, far less attention has been paid to supporting such claims with large-scale, longitudinal data. In this paper, in addition to positing a model of regulatory ecosystems, we document an increase in the regulatory energy per filing, i.e., a warming “temperature.” We also find that the diversity of the regulatory ecosystem has been increasing over the past two decades. These findings support the claim that regulatory activity and complexity are increasing, and this framework contributes an important step towards improving academic and policy discussions around legal complexity and regulation.  相似文献   

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In this work we investigate whether information theory measures like mutual information and transfer entropy, extracted from a bank network, Granger cause financial stress indexes like LIBOR-OIS (London Interbank Offered Rate-Overnight Index Swap) spread, STLFSI (St. Louis Fed Financial Stress Index) and USD/CHF (USA Dollar/Swiss Franc) exchange rate. The information theory measures are extracted from a Gaussian Graphical Model constructed from daily stock time series of the top 74 listed US banks. The graphical model is calculated with a recently developed algorithm (LoGo) which provides very fast inference model that allows us to update the graphical model each market day. We therefore can generate daily time series of mutual information and transfer entropy for each bank of the network. The Granger causality between the bank related measures and the financial stress indexes is investigated with both standard Granger-causality and Partial Granger-causality conditioned on control measures representative of the general economy conditions.  相似文献   

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The 13th annual U.S. National School on Neutron and X-ray Scattering was held June 11-25, 2011, at both Oak Ridge and Argonne National Laboratories. This school brought together 65 early career graduate students from 56 different universities in the United States and provided them with a broad introduction to the properties and techniques available at the major large-scale neutron and synchrotron X-ray facilities. This school is focused primarily on techniques relevant to the physical sciences, but also touches on cross-disciplinary bio-related scattering measurements. During the school, the students received lectures by more than 30 researchers from academia, industry, and national laboratories and participated in a number of short demonstration experiments at Argonne's Advanced Photon Source (APS) and Oak Ridge's Spallation Neutron Source (SNS) and High Flux Isotope Reactor (HFIR) facilities to get hands-on experience in using neutron and synchrotron sources.  相似文献   

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《Solid State Ionics》2006,177(19-25):2039-2044
The U.S. Department of Energy (DOE) Office of Fossil Energy (FE) through the National Energy Technology Laboratory (NETL) is leading the development and demonstration of high efficiency and low cost solid oxide fuel cells (SOFCs) and fuel cell turbine (FCT) hybrid power generation systems primarily under the Solid State Energy Conversion Alliance (SECA). Additional long-term basic research is performed at the High Temperature Electrochemistry Center (HiTEC). Distributed generation (DG) systems have ultra low emissions, produce water, and can be configured to isolate/segregate carbon dioxide – all features useable in FutureGen and advanced coal-based systems.  相似文献   

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This paper proposes a dynamic cascade model to investigate the systemic risk posed by sector-level industries within the U.S. inter-industry network. We then use this model to study the effect of the disruptions presented by Covid-19 on the U.S. economy. We construct a weighted digraph G = (V,E,W) using the industry-by-industry total requirements table for 2018, provided by the Bureau of Economic Analysis (BEA). We impose an initial shock that disrupts the production capacity of one or more industries, and we calculate the propagation of production shortages with a modified Cobb–Douglas production function. For the Covid-19 case, we model the initial shock based on the loss of labor between March and April 2020 as reported by the Bureau of Labor Statistics (BLS). The industries within the network are assigned a resilience that determines the ability of an industry to absorb input losses, such that if the rate of input loss exceeds the resilience, the industry fails, and its outputs go to zero. We observed a critical resilience, such that, below this critical value, the network experienced a catastrophic cascade resulting in total network collapse. Lastly, we model the economic recovery from June 2020 through March 2021 using BLS data.  相似文献   

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Time-resolved radiation dosimetry measurements inside the crew compartment have been made during recent Shuttle missions with the U.S. Air Force Radiation Monitoring Equipment-III (RME-III), a portable battery-powered four-channel tissue equivalent proportional counter. Results from the first six missions are presented and discussed. Half of the missions had orbital inclinations of 28.5 degrees with the remainder at inclinations of 57 degrees or greater; altitudes ranged from 300 to 600 km. The determined dose equivalent rates ranged from 70 to 5300 microSv/day. The RME-III measurements are in good agreement with other dosimetry measurements made aboard the vehicles. Measurements indicate that medium- and high-LET particles contribute less than 2% of the particle fluence for all missions, but up to 50% of the dose equivalent, depending on the spacecraft's altitude and orbital inclination. Isocontours of fluence, dose and dose equivalent rate have been developed from measurements made during the STS-28 mission. The drift rate of the South Atlantic Anomaly is estimated to be 0.49 degrees W/yr and 0.12 degrees N/yr. The calculated trapped proton and GCR dose for the STS-28 mission was significantly lower than the measured values.  相似文献   

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All natural and living systems are governed by atomic and molecular behavior at the nanoscale. Research is now seeking systematic approaches to create revolutionary new products and technologies by control of matter at the same scale. Fundamental discoveries and potential implications of nanotechnology to wealth, health and peace have captured the imagination of scientists, industry and government experts. The National Nanotechnology Initiative (NNI) has become a top national priority in science and technology in U.S. for fiscal year 2001, with a Federal nanotechnology investment portfolio of $422 million. Nanotechnology is expected to have a profound impact on our economy and society in the earlier 21st century.The vision, research and development strategy, and timeline of NNI are presented by using several recent scientific discoveries and results from industry.  相似文献   

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Viviana Fernandez 《Physica A》2007,386(1):267-282
In this article, we study the behavior of the stock prices of a subset of eight U.S. industries from the late 1800's to the Great Depression. In particular, we focus on the potential presence of volatility shifts, the persistence of volatility, and on the degree of co-movement of stock returns prior to and during the Great Depression. Our findings show that stock markets became particularly volatile toward the mid 1930's, but that the persistence of volatility tended to decrease around the same time period. In that regard, we find little evidence that such behavior is driven by trading volume. In addition, we conclude that the overall correlation across the different industries was relatively more significant in statistical terms from 1921 to part of the Great Depression (1929-1931; 1933-1934 and 1936).  相似文献   

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Using the recent work of Hartelman, van der Maas, and Wagenmakers, we demonstrate the use of invariant stochastic catastrophe models in finance for modeling net flows (the difference between purchases and redemptions of fund shares) of U.S. mutual funds. We validate Goetzmann et al. and others' work concerning the importance of sentiment variables on stock fund flows. We also answer some of the questions Goetzmann et al. and Brown et al. pose at the end of their respective papers. We end with possible experiments for experimental economists and sociophysicists.  相似文献   

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U.S. manufacturers of fiber optic equipment continue to be major competitors in the world markets for these products. U.S. producers account for approximately half of the total worldwide production of optical fiber and cable. In active components for fiber optic transmission systems (transmitters, receivers, amplifiers, and related components), U.S. firms are beginning to recapture some of the market share previously lost to foreign competitors. This article provides a brief overview of the competitiveness of U.S. manufacturers in the global market for fiber optic equipment, with particular focus on European and Japanese competitors.  相似文献   

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The intent of this paper is to present some personal observations on the relative strength of U.S. and foreign fiber optics industries. Most of the paper is devoted to a comparison of the Japanese and the American strengths, since these two countries seem to be most active in the field. The potential world market is huge, and this has led to intense competition between countries with highly developed technology.  相似文献   

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Abstract

The intent of this paper is to present some personal observations on the relative strength of U.S. and foreign fiber optics industries. Most of the paper is devoted to a comparison of the Japanese and the American strengths, since these two countries seem to be most active in the field. The potential world market is huge, and this has led to intense competition between countries with highly developed technology.  相似文献   

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This article presents early results from an opinion formation study based on a 76-member panel of U.S. citizens, with comparison data from a group of 177 nanotechnology experts. While initially similar to the expert group in terms of their perceptions of the risks, benefits, and need for regulation characterizing several forms of nanotechnology, the first follow-up survey indicates that the panel is beginning to diverge from the experts, particularly with respect to perceptions of the levels of various “societal” risks that nanotechnology might present. The data suggest that responding to public concerns may involve more than attention to physical risks in areas such as health and environment; concerns about other forms of risk actually appear more salient.  相似文献   

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