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1.
The aim of this paper is to investigate the long and short-run relationship between spot and futures prices of the energy, precious metals, and base metals markets. We analyze daily data from January 1985 to February 2019. The empirical findings based on the cointegration test, which follows a nonlinear process, suggest that the spot prices of energy and metals assets have long-run relationships with their futures prices. Nonparametric Granger causality test results also indicate bi-directional causality among futures and spot prices. These findings indicate that the energy and metals markets are informationally efficient in the sense of Fama (1970). 相似文献
2.
Specialized varieties of sugar beets (Beta vulgaris L.) may be an eligible feedstock for advanced biofuel designation under the USA Energy Independence and Security Act of 2007. These non-food industrial beets could double ethanol production per hectare compared to alternative feedstocks. A mixed-integer mathematical programming model was constructed to determine the breakeven price of ethanol produced from industrial beets, and to determine the optimal size and biorefinery location. The model, based on limited field data, evaluates Southern Plains beet production in a 3-year crop rotation, and beet harvest, transportation, and processing. The optimal strategy depends critically on several assumptions including a just-in-time harvest and delivery system that remains to be tested in field trials. Based on a wet beet to ethanol conversion rate of 110 dm3 Mg−1 and capital cost of 128 M$ for a 152 dam3 y−1 biorefinery, the estimated breakeven ethanol price was 507 $ m−3. The average breakeven production cost of corn (Zea mays L.) grain ethanol ranged from 430 to 552 $ m−3 based on average net corn feedstock cost of 254 and 396 $ m−3 in 2014 and 2013, respectively. The estimated net beet ethanol delivered cost of 207 $ m−3 was lower than the average net corn feedstock cost of 254–396$ m−3 in 2013 and 2014. If for a mature industry, the cost to process beets was equal to the cost to process corn, the beet breakeven ethanol price would be $387 m-3 (587 $ m−3 gasoline equivalent). 相似文献
3.
We investigate the problem of efficient wireless power transfer in wireless sensor networks. In our approach, special mobile entities (called the Mobile Chargers) traverse the network and wirelessly replenish the energy of sensor nodes. In contrast to most current approaches, we envision methods that are distributed and use limited network information. We propose four new protocols for efficient charging, addressing key issues which we identify, most notably (i) what are good coordination procedures for the Mobile Chargers and (ii) what are good trajectories for the Mobile Chargers. Two of our protocols (DC, DCLK) perform distributed, limited network knowledge coordination and charging, while two others (CC, CCGK) perform centralized, global network knowledge coordination and charging. As detailed simulations demonstrate, one of our distributed protocols outperforms a known state of the art method, while its performance gets quite close to the performance of the powerful centralized global knowledge method. 相似文献
4.
Few jurisdictions have translated internationally agreed social impact assessment (SIA) principles into statutory provisions. Governments and regulatory bodies tend to provide developers with high-level frameworks, or require that social impacts be ‘considered’, without specifying how this is to be done. In Australia, this lack of clarity leaves all parties uncertain about requirements for SIA. The New South Wales (NSW) Government’s 2017 release of the SIA guideline for State-significant mining, petroleum and extractive industry development represents an attempt to clarify requirements and provide guidance. In this paper, we describe the process of bringing this guideline to fruition from the perspective of being directly involved in its development, and highlight the challenges involved in integrating leading-practice principles into the state’s pre-existing policy framework. While the guideline represents a significant advance in policy-based SIA guidance, some aspects leave room for improvement. The real test of the guideline’s impact will lie in its influence on SIA practice in NSW, and ultimately in social outcomes for communities affected by resources projects. 相似文献
5.
Journal of Computer Science and Technology - New non-volatile memory (NVM) technologies are expected to replace main memory DRAM (dynamic random access memory) in the near future. NAND flash... 相似文献
6.
A novel synthetic route has been proposed to prepare hausmannite nanoparticles. The synthetic route comprises an iron mediated constant current cathodic electrodeposition of manganite and heat treatment of the latter to obtain hausmannite. The obtained nanostructures have been characterized using X-ray Diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectrometry (EDX) and Fourier transform Infrared Spectrometry (FTIR). The role of iron in the formation of manganite precursor has been studied by cyclic voltammetry (CV) and differential thermal analysis (DTA). A formation mechanism based on iron mediated formation of Mn3+ and subsequent cathodic reduction of the disproportionated products has been proposed accordingly. The prepared nanoparticles exhibited specific capacitance of 143 F g−1 in 0.5 M Na2SO4 solution. The retained specific capacity was 87% after 2000 cycles. 相似文献
7.
《Energy Policy》2015
This article sounds the alarm that a significant build-out of efficient lighting and renewable energy technologies may be endangered by shortages of rare earths and rare earth permanent magnets. At the moment, China is the predominant supplier of both and its recent rare earth industrial policies combined with its own growing demand for rare earths have caused widespread concern. To diversify supplies, new mining—outside of China—is needed. But what many observers of the “rare earth problem” overlook is that China also dominates in (1) the processing of rare earths, particularly the less abundant heavy rare earths, and (2) the supply chains for permanent magnets. Heavy rare earths and permanent magnets are critical for many renewable energy technologies, and it will require decades to develop new non-Chinese deposits, processing capacity, and supply chains. This article clarifies several misconceptions, evaluates frequently proposed solutions, and urges policy makers outside of China to undertake measures to avert a crisis, such as greater support for research and development and for the cultivation of intellectual capital. 相似文献
8.
近年来,国有科研单位,尤其是地处经济不发达地区的国有科研单位,出现了较为严重的人才流失现象,一定程度上影响和制约了国有科研单位的发展。通过对国有科研单位人才流失原因的分析,提出了相应的对策。 相似文献
9.
The effects of parameter uncertainty on optimal policy have been a matter of interest for academics, and even for some policymakers,
for a long time. Two lines of literature have developed analytical results on this matter. The first line uses static models
and the second dynamic models. In this dynamic line most of the results are confined to models with a single state and a single
control variable.
In this paper we want to encourage the analysis of more general dynamic cases. To do so, the results in the dynamic line are
extended from one-state and one-control finite horizon models to models with a pair of control variables. We then discuss
some of the hurdles which must be surmounted for the results to be made more general and suggests some lines for further research.
JEL classification: C61; E61 相似文献
10.
《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》2003,510(3):248-261
The energy dependence of the energy and position resolutions of the electromagnetic calorimeter prototype made of lead tungstate crystals produced in Bogoroditsk (Russia) and Shanghai (China) is presented. These measurements were carried out at the Protvino accelerator using a 1–45 GeV electron beam. The crystals were coupled to photomultiplier tubes. The dependence of energy and position resolutions on different factors as well as the measured electromagnetic shower lateral profile are presented. 相似文献