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The kernel extreme learning machine (KELM) is more robust and has a faster learning speed when compared with the traditional neural networks, and thus it is increasingly gaining attention in hyperspectral image (HSI) classification. Although the Gaussian radial basis function kernel widely used in KELM has achieved promising classification performance in supervised HSI classification, it does not consider the underlying data structure of HSIs. In this paper, we propose a novel spectral-spatial KELM method (termed as MF-KELM) by incorporating the mean filtering kernel into the KELM model, which can properly compute the mean value of the spatial neighboring pixels in the kernel space. Considering that in the situation of limited training samples the classification result is very noisy, the spatial bilateral filtering information on spectral band-subsets is introduced to improve the accuracy. Experiment results show that our method outperforms other kernel functions based on KELM in terms of classification accuracy and visual comparison.
In an effort to fight against local protectionism in court enforcement proceedings, China's Supreme People's Court (SPC) promulgated its “Notice on relevant issues pertaining to the people's court handling foreign and foreign-related arbitration” in 1995. Pursuant to this Notice, all Intermediate People's Courts have to report to the SPC and obtain its approval for any decision not to enforce a foreign or foreign-related arbitral award. However, the effectiveness of this internal reporting mechanism in constraining local protectionism has never been empirically tested. This study is based on 98 publicly available non-enforcement reply opinions rendered by the SPC after lower courts have made and reported preliminary non-enforcement decisions. It analyses whether these non-enforcement decisions show any pattern of local protectionism. Statistical results do not suggest that local protectionism is a major barrier hindering effective enforcement of foreign or foreign-related arbitral awards in China. We therefore contend that this internal reporting system may serve other functions by providing an alternative tool to reinforce judicial oversight in spite of China's weak appellant system. At the same time, the Chinese government seems to rely on this internal reporting system to achieve important policy goals. In this sense, analysing the functionality of this internal reporting system offers insights into this mechanism for top-level judicial control.
This article examines the state sovereign immunity rule in the context of a rising number of sovereign wealth funds and their ever-increasing value of cross-border commercial activities in the aftermath of the latest global financial crisis. The concept of sovereignty and the rule of sovereignty remain in a state of flux while new actors such as sovereign wealth funds are participating in global commercial activities in a nontransparent and politically motivated manner. Accordingly, states may pursue strategic foreign policy objectives through these newer investment arms in an unconventional way, thereby being deeply involved in the political-economic arena and distorting the existing concepts of international law. This article posits that there is an international law black hole in which sovereign wealth funds have come to engage in commercial activities as well as exercise the public functions traditionally associated with states (acts jure imperii). The doctrine of restrictive immunity has come into question and the bulk of local court decisions have offered little clear guidance. Against this backdrop three interconnected perspectives are then discussed with reference to emerging economies like China: the immunity rule, the principle of sovereignty, and the balance of power in globalization.
The lithium ion battery is the most promising battery candidate to power battery electric vehicles. For these vehicles to be competitive with those powered by conventional internal combustion engines, significant improvements in battery performance are needed, especially in the energy density and power delivery capabilities. Promising substitutes for graphite as the anode material include silicon, tin, germanium, and various metal oxides that have much higher theoretical storage capacities and operated at slightly higher and safer potentials. In this critical review, metal oxides-based materials for lithium ion battery anodes are reviewed in detail together with the progress which is made in my lab on that topic. Their advantages, disadvantages, and performance in lithium ion batteries are discussed through extensive analysis of the literature, and new trends in materials development are also reviewed. Two important future research directions are proposed and performed in my lab, based on results published in the literature: the development of composite and nanostructured metal oxides to overcome the major challenge posed by the high capacity of metal oxide anodes.
Methods of imaging and image analysis are presented for dusty plasma experiments. Micron-sized polymer spheres, electrically suspended in a partially ionized gas, are illuminated by a sheet of laser light and imaged by video cameras. Image analysis methods yield particle positions and velocities of individual particles in each video image. Methods to minimize errors in the particle positions and velocities, which are now commonly used in the dusty plasma community, are described.
Gauged river flow records from China generally span only a few decades, which hampers the detection of long-term, decadal- to centennial-scale cycles and trends in streamflow variability. New and updated tree-ring chronologies help reconstructed the water-year (October–September) streamflow for the Aksu River, which is an important river at the edge of the Taklimakan Desert that drains into the Tarim Basin. The reconstruction dates back to 1692 and has an adjusted r2 of 0.61 (1957–2006). Based on frequency, intensity and duration of droughts and pluvial events, the lowest streamflows occurred in the 1920s. Since then streamflow has continuously increased, and was exceptionally rapidly after the 1960s, until today. The start and end of the 20th century to the present were the highest streamflow periods. The mid-20th century was the longest and driest period over the past 300 yr. The reconstructed streamflow series has a strong positive correlation with the North Atlantic Oscillation Index. Changes in mid-latitude circulation patterns influencing precipitation may have indirectly resulted in streamflow variations along the Aksu River over the past 300 yr. The rapid increase and the exceptional streamflows of the 1960s are likely linked with global warming and mid-latitude atmospheric circulation changes.
Electron cyclotron maser (ECM) instability is today’s most favoured process for microwave spike emission. Although ECM looks attractive, the emission mechanism is still unclear due to the imperfection of present theories, inadequacy of observational data, and uncertainty as to conditions in the source region. To find solar active phenomena, both statistically and individually coincident with radio spike events, is essential for understanding the ambient conditions needed for generating spike emission, locating sites where spike emission is produced, and providing clues for particle acceleration and energy release in flares.
In this paper, evidence for an association between spike emission at 21 cm and fast variation of the magnetic configuration in post-flare loops is presented. Such associations may be helpful for solving the questions mentioned above.
This study was to analyze the microstructure, microhardness, tensile and fatigue performance of the welded joints performed by a fiber laser on 22MnB5 and dual-phase steels (DP590, DP980) in similar and dissimilar combinations. The result shows that the weld zone (WZ) basically consisted of lath martensite. The HAZ in these steels can be divided into 3 parts: quenched, incomplete quenched, and tempered region. The WZ had the highest hardness, and a soft zone existed in the HAZ of all steels. Inside the WZ of the dissimilar welded joints, two hardness subregions were observed due to the difference in the alloying elements of these steels. Tensile specimens of the 22MnB5–22MnB5 and 22MnB5–DP980 welded joints were all broken in HAZ, while the 22MnB5–DP590 welded joints failed in the DP590 base metal (BM). The BM had a higher fatigue life than the welded joints, and the fatigue failure of the 22MnB5 similar and 22MnB5–DP980 dissimilar welded joints respectively occurred in the HAZ and DP980 BM. The fatigue fracture contained 3 parts: crack initiation, crack propagation, and the final fast fracture region.
Sediment resuspension is an important internal lake process in regulating nutrient cycling and ecosystem structure. Tubificid worms are widely and abundantly distributed in freshwater ecosystems and are able to alter the sediment characteristics. This study was conducted to verify the hypothesis that the alteration of sediments by tubificids may substantially influence the sediment resuspension process. Specifically, we investigated the influence of Limnodrilus hoffmeisteri (Tubificidae) on sediment resuspension using an apparatus designed to simulate the sediment resuspension process in Lake Taihu (China). We examined L. hoffmeisteri according to its density (30 000 ind.m−2) in Lake Taihu and simulated the light (3.2 m.s−1), moderate (5.1 m.s−1) and strong (8.7 m.s−1) wind processes present in Lake Taihu. Tubificids loosened the sediment through their feeding and defecation activities and increased the sediment water content. The appearance of tubificids increased the suspended solids (SS) in a 1.6 m water column under all three wind processes. During the sedimentation process, SS decreased rapidly in both the control and tubificid treatments. The total SS in the water column was significantly increased by tubificids and it changed significantly with time. In addition, the small size particles of the SS in the tubificid treatment were higher than that in the control. So, the appearance of tubificid worms (L. hoffmeisteri) enhanced sediment resuspension and raised the proportion of small size particles in SS.
August–July precipitation has been reconstructed back to AD 1724 for the Mohe region in the northern Greater Higgnan Mountains, China, using Pinus sylvestris var. mongolica tree-ring width. The reconstruction explains 39% of the variance in the precipitation observed from AD 1960–2008. Some droughts noted in historical documents are precisely captured in our reconstruction. Wet periods occurred during the periods of AD 1734–1785, AD 1805–1830, AD 1863–1880, AD 1922–1961, and AD 1983–1998; while the periods of AD 1786–1804, AD 1831–1862, AD 1881–1921, and AD 1962–1982 were relatively dry. Power spectral and wavelet analyses demonstrated the existence of significant 24-yr, 12-yr, and 2-yr cycles of variability. The results of the spatial correlations suggest that our reconstruction contains climatic signals for the southern Stanovoy Range and the northern Greater Higgnan Mountains. The positive correlations between the new reconstructed precipitation series and two precipitation reconstructions indicate that our precipitation reconstruction captures broad-scale regional climatic variations. A comparison between the weakening tendency of summer monsoon and the dry period of our reconstruction reveals that the annual precipitation in the Mohe region is partly influenced by the East Asian Summer Monsoon.
We have developed a low cost and convenient approach to fabricate ITO-comparable transparent electrodes by using solution process of silver nanowires mixed with poly peroxotitanic acid (PPT) gel. The PPT gel is applied to connect the dispersed silver nanowires to preserve its high conductivity while remaining transparency and reducing surface roughness of the transparent electrode. The silver nanowires were synthesized via a modified polyol method, and the PPT gels were prepared by sol-gel method in appropriate concentrations. After applying the PPT gels, the sheet resistance of the transparent electrodes was improved from 192 Ω/□ to 44.7 Ω/□ with a transmittance of 81 %. And the roughness (RMS) was decreased from 106.3 nm to 48.1 nm. The PPT gel also improved the reliability of the proposed electrodes, which the conductivity was remained after general atmospheric storage of 6 months. We also demonstrate an Alq3 based OLED with the proposed transparent electrodes.
For cable-driven parallel manipulators (CDPMs), it is known that maintaining positive cable tension is critical in constraining the moving platform. Hence, the force-closure workspace of CDPMs represents a set of poses where the cable tensions can balance arbitrary external wrench applied on the moving platform, proposed by researchers. A new computation method for the force-closure workspace of CDPMs is developed in this paper, and the new method is realized by calculating the null space of the structure matrix and solving the linear matrix inequalities. The detailed calculation procedures of the force-closure workspace for the incompletely restrained, completely restrained, and redundantly restrained CDPMs are given, respectively, and the advantages of the new method are analyzed according to the time complexity. The simulation experiments of the force-closure workspace computation are implemented on a six-degree of freedom (6-DOF) CDPM with eight cables, and then the superiority of the new method over the existing algorithm is studied.
Three robust tree-ring density chronologies were developed for the western Tianshan Mountains of northwestern China. The chronologies were significantly correlated and form a regional chronology (GLD). The GLD had significant and positive correlations with temperature of warm seasons. Based on this relationship, the mean minimum temperatures of May to August were reconstructed using the GLD chronology for the period AD 1657 to 2008. The temperature reconstruction exhibited temperature patterns on interannual to centennial timescales, and showed that the end of the 20th century is the warmest period in the past 352 years. The reconstructed temperature variation has a teleconnection with large-scale atmospheric–oceanic variability and captures long- and broad-scale regional climatic variations.
In understanding the sources of China's growth success, one theory is that the Chinese government's active and successful promotion of industrial upgrading, rather than passively waiting for market-determined natural evolution of its comparative advantage, is a key for its sustained high growth rates. One possible market failure that could justify government promotion of industrial upgrading is the externality of discovering a country's latent comparative advantage. If the benefits of the discovery are not accrued fully to the firms that make the initial investment in the costly discovery, then private firms generally underinvest in the discovery process (Hausmann and Rodrik 2003). As a result, the natural evolution of a country's comparative advantage may be too slow. Other types of market failure also could justify a role for the government in promoting structural upgrading that would make a country's industrial composition appear precocious relative to its current income level or factor endowment.
A popular measure of precocious industrial structure is the difference between a country's actual export bundle relative to the expected mix based on its income or factor endowment. By this measure, China's export structure appears precociously advanced. Across countries, Rodrik (2006) and Hausmann et al. (2007) reported that those countries with a more precocious export structure tend to grow faster – and China is simply an illustration of this. Schott (2008) documented an apparent rapid increase in the similarity between the People's Republic of China (PRC)'s export structure and that of high-income countries and interpreted it as evidence of a rise in the level of sophistication embedded in the country's exports.
An adaptive computed torque (ACT) controller in the task space is proposed for the trajectory tracking of a parallel manipulator with redundant actuation. The dynamic model, including the active joint friction, is established in the task space for the parallel manipulator, and the linear parameterization expression with respect to the dynamic and friction parameters is formulated. On the basis of the dynamic model, a new control law, which contains adaptive dynamics compensation, friction compensation, and tracking error elimination terms, is designed. After defining the state-space model of the error system, the parameter adaptation law is derived by using the Lyapunov method, and the convergence of the tracking error and the error rate is proved by using the Barbalat's lemma. The ACT controller is implemented in the trajectory tracking experiments of an actual 2-DOF parallel manipulator with redundant actuation, and the experiment results are compared with the computed torque controller.
(In)GaAsN based heterostructures have been found to be promising candidates for the active region of 1.3 micron VCSELs. However, (In)GaAsN bulk layers and quantum wells usually demonstrate lower photoluminescence intensity than their nitrogen-free analogues. Defects associated with lower temperature growth and N-related defects due to plasma cell operation and possible nonuniform distribution of nitrogen enhance the non-radiative recombination in N-contained layers. We studied the photoluminescence intensity of GaAsN layers as a function of N content in MBE grown samples using rf-plasma source. Increasing the growth temperature to as high as 520 °C in combination with the increase in the growth rate allowed us to avoid any N-related defects up to 1.5% of nitrogen. Low-temperature-growth defects can be removed by post-growth annealing. We achieved the same radiative efficiency of GaAsN samples grown at 520°C with that of reference layer of GaAs grown at 600°C. Compositional fluctuations in GaAsN layers lead to characteristic S-shape of temperature dependence of photoluminescence peak position and this feature is the more pronounced the higher the amount of nitrogen in GaAsN. Annealing reduces compositional fluctuations in addition to the increase in the photoluminescence intensity. The results obtained are important for further improving the characteristics of InGaAsN lasers emitting at 1.3 micron.
The years under study in this chapter are often retrospectively called the high Qing or middle Qing era. Following the sixty-one years of the Kangxi reign (1662–1722) was a relatively short rule by the Yongzheng Emperor (1723–1735), which in turn was followed by the Qianlong reign (1736–1796), an era as glorious and almost as long as the Kangxi reign. In 1795, the eighty-four year old Qianlong Emperor decided to abdicate the throne, so as not to surpass the record length of his grandfather’s rule. The accession of the Jiaqing Emperor brought a change of reign title but little else; Qianlong continued to rule behind the scenes, though with less vigor and interest, until his death in 1799. His last years, however, proved crucial to the future of the Qing empire. Historians often remind us that the 1790s saw an acceleration of the slide toward chaos, from which the two ensuing reigns – Jiaqing (1796–1820) and Daoguang (1821–1850) – never managed to recover.
The familiar drama of a dynastic cycle coming to an end this time concluded with two cataclysmic events. In 1840, the first Opium War broke out. With modern weaponry, Great Britain blew open the doors of the Qing empire in the name of protecting British citizens and their property. The war brought to the fore problems that can be traced back to the Qianlong years, when the British opium trade began to disturb the balance of currency exchange by creating shortages of silver and produced a large population of opium addicts. Qing’s defeat in this war, however, was much more than a military, commercial, and economic event; its profound impact on Chinese political, intellectual, and literary life would become apparent only in the years to come.
Nitrogen was doped into titanium dioxide film to alter its surface electrostatic properties, and subsequently modulate the interaction force between MS2 virus and semiconductor films for control of the adsorption behavior of MS2 on semiconductor surfaces. By combining atomic force microscopy (AFM) height profile and phase profile, adsorptions of MS2 virus on TiO2-based semiconductor surfaces were observed in solutions over a range of pH values. The adsorption behavior was shown to agree with the theoretical analysis of colloidal interactions.
Jeffrey Frankel, James W. Harpel Professor of Capital Formation and Growth, Kennedy School of Government, Harvard University,
Shang-Jin Wei, Chief Trade and Investment Division, Research Department, International Monetary Fund
ABSTRACT: This study is an attempt to review broadly what the last decade reveals about which policies for crisis prevention or crisis management seem to work and which do not. The empirical investigation tries out a variety of methodological approaches: reasoning from examples of prominent crises of the last eight years, formal probit analysis, a regression tree analysis, conventional regression analysis, and a look at the typical profile of financing during the sudden stop preceding a crisis.
We seek to draw greater attention to policy decisions that are made during the phase when capital inflows come to a sudden stop. Procrastination – the period of financing a balance of payments deficit rather than adjusting – had serious consequences in some cases. Crises are more frequent and more severe when short-term borrowing and dollar denominated external debt are high, and foreign direct investment (FDI) and reserves are low, in large part because balance sheets are then very sensitive to increases in exchange rates and short-term interest rates.
Our point is that these compositional measures are affected by decisions made by policymakers in the period immediately after capital inflows have begun to dry up but before the speculative attack itself has hit. If countries that are faced with a fall in inflows adjusted more promptly, rather than stalling for time by running down reserves or shifting to loans that are shorter-termed and dollar-denominated, they might be able to adjust on more attractive terms.
In the last 30 years, emerging markets have experienced at least two complete boom-bust cycles.[…]