Cluster ensembles: A survey of approaches with recent extensions and applications

Cluster ensembles have been shown to be better than any standard clustering algorithm at improving accuracy and robustness across different data collections. This meta-learning formalism also helps users to overcome the dilemma of selecting an appropriate technique and the corresponding parameters, given a set of data to be investigated. Almost two decades after the first publication of a kind, the method has proven effective for many problem domains, especially microarray data analysis and its down-streaming applications. Recently, it has been greatly extended both in terms of theoretical modelling and deployment to problem solving. The survey attempts to match this emerging attention with the provision of fundamental basis and theoretical details of state-of-the-art methods found in the present literature. It yields the ranges of ensemble generation strategies, summarization and representation of ensemble members, as well as the topic of consensus clustering. This review also includes different applications and extensions of cluster ensemble, with several research issues and challenges being highlighted.     

Small-scale portable photovoltaic-battery-LED systems with submersible LED units to replace kerosene-based artisanal fishing lamps for Sub-Saharan African lakes

A technical simulation and economic model was developed for a floating photovoltaic (PV)-battery system powering a submerged light emitting diode (LED) lighting system. The system was designed to provide around the equivalent of 1000 lumens (lm) of light of the existing light fishing technology (a floating pressurised kerosene light) for artisanal light fishers to use for 8 h per night on Lake Victoria and other lakes in the region (Tanganyika, Rukwa, Mweru, Kivu, etc.). The net present cost (NPC) of a technically appropriate PV-battery-LED system was calculated as US$280 over 5 years, five-times less than the existing solar-based technology, a PV-battery-compact fluorescent lamp (CFL) system, and around ten times less than the baseline pressurised kerosene-based technology over the five years. Fishers owning the new PV-battery-LED system outright will likely recoup their initial investment within a year relative to the cost of alternatives, although the upfront capital cost of the new system was higher than the pressurised kerosene and PV-battery-CFL, and found to be practically unaffordable to the subsistence fishers without microcredit. Nonetheless, the technical simulations found that the new system was also able to provide additional lighting services during the day and evening, with little (if any) electrical impact on the system when in use for light fishing during the small hours of moonless nights. This research also demonstrates that the high cost of operating pressurised kerosene lamps precludes them for use in other applications within the community, including in homes. This research suggests that facilitated local development of appropriate new light fishing technology configurations will require training of local individuals to sensitise fishing communities to the new technology, and sustain wider adoption of the more efficient, cost-effective, and safer alternative.     

A facile method to synthesize carbon coated Li1.2Ni0.2Mn0.6O2 with improved performance

Carbon-coated Li_1.2Ni_0.2Mn_0.6O₂ powders have been synthesized with Bakelite and heat process in air. The effect of carbon coating on the physical and electrochemical properties have been discussed through the characterizations of X-ray diffraction (XRD), scanning electron microscopy (SEM), electrochemical impedance spectroscopy (EIS), discharge and rate tests. The carbon-coated cathode exhibits much improved first discharge capacity and rate capability than the pristine sample. The discharge capacity at 0.1 and 5.0 C rates are 246 and 125 mAhg⁻¹, while that of pristine are only about 222 and 49 mAhg⁻¹, respectively. The capacity retention of Li_1.2Ni_0.2Mn_0.6O₂ electrode after 50 cycles is improved from 89.8 to 97.5% after carbon coating. EIS results indicate that R_ct of Li_1.2Ni_0.2Mn_0.6O₂ electrode is decreased from 62 to 37 Ω after carbon coating.     

英语修辞问句的构成及其话语和语篇功能简析

英语修辞问句，以主谓倒装的疑问句结构形式出现，句末可以使用问号，句号或感叹号，其本质上不要求读者或听众提供答案，而是起特定的话语或篇章修辞效果。这些效果包括吸引读者或听众的注意力，激发对方的兴趣，获取对方的支持，充当模糊限定语，加强语势，突出重点，强调前述论点，提起新的话轮，回答问题等。对英语修辞问句语篇功能的了解，有助于提高英语学习者的阅读和理解能力。     

Current states of coalbed methane and its sustainability perspectives in China

With the rapid development of China's economy in the recent years, the gap between energy supply and demand has been gradually enlarged. To solve the problem of insufficient reserves of natural gas, greenhouse effect, and safety of coal mines, coalbed methane (CBM) is considered as an effective substitute. First of all, CBM industry status is introduced, mainly including resource endowment, development status, technical conditions, and market environment. Then, the policy environment of CBM in China was summarized into 6 aspects: price policy, tax policy, financial subsidy policy, resource management policy, foreign cooperation policy, and other policies. Thirdly, through Politics, Economics, Society, and Technology analysis, Strength, Weakness, Opportunities, and Threats analysis, Politics, Economics, Society, and Technology‐Strength, Weakness, Opportunities, and Threats analysis, and Comparative Analysis, the influence of political factors, economic factors, social factors, and technological factors on CBM industry is analyzed, and the strengths, weaknesses, opportunities, and threats of CBM development are pointed out. Fourth, through the above analysis, development proposal is given from 3 aspects which include policy support, technical support, and market support. Finally, through the analysis of the industry, the related conclusions and the prospect of China's CBM are put forward.     

Enhancing multisensor data fusion on light sectioning coordinate measuring systems for the in-process inspection of freeform shaped parts

A method for automatic determination of sensors positions and orientations in multisensor laser triangulation coordinate measuring systems is presented. Based on a series of measurements on a conical artifact without the use of external light sources, the approach allows for both optimized adjustment of the physical sensors alignment and improved 3D data registration by software. Simulations were conducted to quantify the sensitivity of the method. Experimental results based on measurements of steep details of complex shaped parts show a 5-times reduction of deviations between measurements of sensors with respect to an already optimized adjustment by manual methods.     

Convolutional neural network based deep conditional random fields for stereo matching

Stereo matching has been studied for many years and is still a challenge problem. The Markov Random Fields (MRF) model and the Conditional Random Fields (CRF) model based methods have achieved good performance recently. Based on these pioneer works, a deep conditional random fields based stereo matching algorithm is proposed in this paper, which draws a connection between the Convolutional Neural Network (CNN) and CRF. The object knowledge is used as a soft constraint, which can effectively improve the depth estimation accuracy. Moreover, we proposed a CNN potential function that learns the potentials of CRF in a CNN framework. The inference of the CRF model is formulated as a Recurrent Neural Network (RNN). A variety of experiments have been conducted on KITTI and Middlebury benchmark. The results show that the proposed algorithm can produce state-of-the-art results and outperform other MRF-based or CRF-based methods.     

Vortex States of a Three-Dimensional Mesoscopic Superconducting Torus in an External Magnetic Field

The time-dependent Ginzburg–Landau equations have been solved numerically by the finite-element method for a three-dimensional mesoscopic superconducting torus. We obtain the different vortex patterns as a function of the applied field perpendicular to its surface. And we find that multivortex states are ground state in a three-dimensional mesoscopic torus. These results show that our approach is effective and useful to interpret experimental data on vortex states in mesoscopic superconductors.     

Inhibition of copper corrosion in sodium chloride solution by the self-assembled monolayer of sodium diethyldithiocarbamate

Sodium diethyldithiocarbamate (DDTC) self-assembled monolayer (SAM) on copper surface has been investigated by SERS and EDS and the results show that DDTC SAM is chemisorbed on copper surface by its S atoms with tilted orientation. Corrosion inhibition ability of DDTC SAM was measured in 3% NaCl solution using electrochemical methods. The impedance results indicate that the maximum inhibition efficiency of DDTC SAM can reach 99%. Quantum chemical calculations show that DDTC has relatively small ΔE between HOMO and LUMO and large negative charge in its two sulfur atoms, which facilitates the formation of a DDTC SAM on copper surface.     

Gold nanoparticles incorporated mesoporous silica thin films of varied gold contents and their well-tuned third-order optical nonlinearities

Gold nanoparticles (NPs) incorporated mesoporous silica thin films (MSTFs) of varied gold contents from 4.64 to 29.15 wt.% were synthesized through a refined chemical modification to the mesopore surface using different amounts of silane with amino end group. The microstructures of the composite thin films were characterized and the off-resonant third-order optical nonlinearities of the composite thin films were investigated by Z-scan technique at 1064 nm. The resultant composite thin films showed increased third-order optical nonlinear susceptibility (χ⁽³⁾) from 4.26 × 10⁻¹¹ to 9.24 × 10⁻¹⁰ esu at increased gold contents. The dependence of χ⁽³⁾ on gold content have been discussed, which can be described by an exponent function y = y₀ + Ae^−x/t when the gold contents of the composite thin films were below 30 wt.%.