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This paper revisits set containment join (SCJ) problem, which uses the subset relationship (i.e., ⊆ ) as condition to join set-valued attributes of two relations and has many fundamental applications in commercial and scientific fields. Existing in-memory algorithms for SCJ are either signature-based or prefix-tree-based. The former incurs high CPU cost because of the enumeration of signatures, while the latter incurs high space cost because of the storage of prefix trees. This paper proposes a new adaptive parameter-free in-memory algorithm, named as frequency-hashjoin or FreshJoin in short, to evaluate SCJ efficiently. FreshJoin builds a flat index on-the-fly to record three kinds of signatures (i.e., two least frequent elements and a hash signature whose length is determined adaptively by the frequencies of elements in the universe set). The index consists of two sparse inverted indices and two arrays which record hash signatures of all sets in each relation. The index is well organized such that FreshJoin can avoid enumerating hash signatures. The rationality of this design is explained. And, the time and space cost of the proposed algorithm, which provide a rule to choose FreshJoin from existing algorithms, are analyzed. Experiments on 16 real-life datasets show that FreshJoin usually reduces more than 50% of space cost while remains as competitive as the state-of-the-art algorithms in running time. [ABSTRACT FROM AUTHOR]

Mining industries worldwide have inevitably resorted to exploiting resources from the deep underground. However, traditional mining methods can cause various problems, e.g., considerable mining difficulty, environmental degradations, and frequent disastrous accidents. To exploit deep resources in the future, the concept of mining must be reconsidered and innovative new theories, methods, and technologies must be applied. To effectively acquire coal resources deeper than 2000 m, new theoretical and technological concepts about deep in situ fluidized mining are required. The limits of mining depth need to be broken to acquire deep-coal resources in an environmentally friendly, safe, and efficient manner. This is characterized by 'There are no coal on the ground and no men in the coal mine'. First, this paper systematically explains deep in situ fluidized coal mining. Then, it presents a new theoretical concept, including the theories of mining-induced rock mechanics, three-field visualization, multi-physics coupling for in situ transformation, and in situ mining, transformation and transport. It also presents key technological concepts, including those of intelligent, unmanned, and fluidized mining. Finally, this paper presents a strategic roadmap for deep in situ fluidized coal mining. In summary, this paper develops new theoretical and technological systems for accomplishing groundbreaking innovations in mining technologies of coal resources in the deep underground. [ABSTRACT FROM AUTHOR]

This article presents a high-precision multi-modal approach for localizing moving cameras with monocular videos, which has wide potentials in many intelligent applications, including robotics, autonomous vehicles, and so on. Existing visual odometry methods often suffer from symmetric or repetitive scene patterns, e.g., windows on buildings or parking stalls. To address this issue, we introduce a robust camera localization method that contributes in two aspects. First, we formulate feature tracking, the critical step of visual odometry, as a hierarchical min-cost network flow optimization task, and we regularize the formula with flow constraints, cross-scale consistencies, and motion heuristics. The proposed regularized formula is capable of adaptively selecting distinctive features or feature combinations, which is more effective than traditional methods that detect and group repetitive patterns in a separate step. Second, we develop a joint formula for integrating dense visual odometry and sparse GPS readings in a common reference coordinate. The fusion process is guided with high-order statistics knowledge to suppress the impacts of noises, clusters, and model drifting. We evaluate the proposed camera localization method on both public video datasets and a newly created dataset that includes scenes full of repetitive patterns. Results with comparisons show that our method can achieve comparable performance to state-of-the-art methods and is particularly effective for addressing repetitive pattern issues. [ABSTRACT FROM AUTHOR]

Objective: To investigate the association between radiotherapy and anatomic severity of coronary artery disease (CAD) using the SYNTAX scores (SXscores) of coronary angiograms in adult-onset thoracic cancer survivors. Methods: A total of 152 patients who previously had thoracic cancer and underwent coronary angiography between 2010 and 2016 were examined. Propensity score matching (PSM) was used to identify 27 well-matched pairs of patients. Characteristics and coronary angiograms were collected from each patient. Coronary artery abnormalities were assessed using SXscores of coronary angiograms. Results: Among the 152 patients, the SXscores and percentage of high SXscores were higher in the radiotherapy group than in the non-radiotherapy group; however, the latter was not significantly different (p = 0.0266 and p = 0.064, respectively). After PSM, the SXscores and percentage of high SXscores were significantly higher in the radiotherapy group than in the non-radiotherapy group (22 [interquartile range (IQR) 10.00–30.00] vs. 15.00 [IQR 4.00–26.00], p = 0.0459), (70.07 vs. 44.44%, p = 0.027), respectively. After adjusting for related risk factors and chemotherapy, the OR of radiotherapy for a high SXscore was 3.674 (95% CI 1.094–12.343) by logistic regression analysis. Conclusion: Thoracic cancer survivors who underwent radiotherapy have higher SXscores and are at a higher risk of developing anatomically severe CAD, independent of chemotherapy. [ABSTRACT FROM AUTHOR]

Background: MRI signal diffusion-weighted imaging (DWI) hyperintensity in the hippocampus in patients with transient global amnesia (TGA) are resolved within several days after the onset of TGA.Purpose: To use multiparametric MRI to unravel the sequelae of TGA.Study Type: A prospective longitudinal study.Population: Eight TGA patients.Field Strength/sequence: A 3.0T Siemens Tim Trio MRI scanner with T1 -weighted MPRAGE, diffusion-weighted echo planar imaging, and multiecho gradient-recalled echo sequences.Assessment: Brain MRI scanned within 72 hours, 2 weeks, and 3 months after onset of TGA, respectively. T1 image hippocampus was first segmented into 12 subregions using FreeSurfer and registered to DWI to locate DWI lesion. Then a T1 image with segmented hippocampus was registered to its corresponding apparent diffusion coefficient (ADC) map, fractional anisotropy (FA) map, and quantitative susceptibility map, respectively. Finally, the volume, water diffusion and anisotropy, and magnetic susceptibility of DWI lesion were analyzed.Statistical Tests: A paired samples t-test was performed to detect measurement differences between three tests. Pearson correlation was used to assess the correlations between all measurements.Results: Hyperintensity was detected in the head, body, and caudate of CA1 and hippocampal tail. No significant changes existed in CA1/unit volume across the three timepoint measurements (all, P > 0.480). In Test 1, ratio ADC (DWI lesion / adjacent healthy, rADC) and ratio FA (rFA) decreased below, while ratio susceptibility increased above 1.0. In Test 2, all the episodes normalized around 1.0. In Test 3, rADC remained normalization, but rFA decreased and ratio susceptibility increased again. In Test 1 and Test 3 (vs. Test 2), decreased FA values were accompanied with lower axial diffusivity and/or higher radial diffusivity (all, P < 0.001). Moreover, rFA significantly correlated with ratio susceptibility in Test 3 (r = -0.665, P = 0.039).Data Conclusion: Microstructural sequelae in hippocampus were demonstrated, which indicates that ischemic lesions may be associated with TGA.Level Of Evidence: 2 Technical Efficacy: Stage 3 J. Magn. Reson. Imaging 2018;47:1350-1358. [ABSTRACT FROM AUTHOR]

Composite event detection is one of the fundamental tasks for heterogeneous wireless sensor networks (WSNs). Multi-modal data generated by heterogeneous sensors bring new challenges for composite event monitoring in heterogeneous WSNs. By exploiting the correlations between different types of data, the approximate composite event detection problem is investigated in this paper. The optimal transmitting scheme problem is proposed to calculate the optimal transmitting scheme with minimum cost on the constraint that the confidence of the composite event must exceed the threshold. The optimal transmitting scheme problem is proved to belong to NP-complete. A dynamic programming based algorithm is presented for simple linear confidence combination operators, which runs in pseudo-polynomial time. The greedy based approximate algorithm is also designed for general confidence combination operators and the approximate ratio is proved to be 2 for '+' as the confidence combination operator. The simulation results show that our algorithms can reduce energy consumption significantly. [ABSTRACT FROM AUTHOR]

Data sharing among multiple sampling tasks significantly reduces energy consumption and communication cost in low-power wireless sensor networks (WSNs). Conventional proposals have already scheduled the discrete point sampling tasks to decrease the amount of sampled data. However, less effort has been expended for applications that generate continuous interval sampling tasks. Moreover, most pioneering work limits its view to schedule sampling intervals of tasks on a single sensor node and neglects the process of task allocation in WSNs. Therefore, the gained efforts in prior work cannot benefit a large-scaleWSN because the performance of a scheduling method is sensitive to the strategy of task allocation. Broadening the scope to an entire network, this article is the first work to maximize data sharing among continuous interval sampling tasks by jointly optimizing task allocation and scheduling of sampling intervals in WSNs. First, we formalize the joint optimization problem and prove it NP-hard. Second, we present the COMBINE operation, which is the crucial ingredient of our solution. COMBINE is a 2-factor approximate algorithm for maximizing data sharing among overlapping tasks. Furthermore, our heuristic named CATS is proposed. CATS is 2-factor approximate algorithm for jointly allocating tasks and scheduling sampling intervals so as to maximize data sharing in the entire network. Extensive empirical study is conducted on a testbed of 50 sensor nodes to evaluate the effectiveness of our methods. In addition, the scalability of our methods is verified by utilizing TOSSIM, a widely used simulation tool. The experimental results indicate that our methods successfully reduce the volume of sampled data and decrease energy consumption significantly. [ABSTRACT FROM AUTHOR]

ABSTRACT The hydrolysis of poly(ethylene terephthalate) (PET) obtained from waste bottles was studied. The dual functional phase transfer catalyst [(CH3)3N(C16H33)]3[PW12O40] exhibited outstanding catalytic activity to the hydrolysis of PET. Fourier transform infrared spectroscopy and proton nuclear magnetic resonance spectroscopy were used to confirm the main product terephthalic acid (TPA) of hydrolysis. The effects of temperature, time, particle size of PET and dosage of catalyst on hydrolysis reaction were examined. Under the optimum conditions of reaction temperature 145°C, time 2 h, particle size of PET at 0.5-1 mm and dosage of catalyst at 7 wt %, the conversion of PET and the yield of TPA were almost 100% and 93%, respectively. After easily separated from the product, the catalyst could be reused more than three times without obvious decrease in the conversion of PET and yield of TPA. An economical and convenient process was developed for hydrolysis of PET. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 2790-2795, 2013 [ABSTRACT FROM AUTHOR]

This paper deals with the problem of city scale on-device mobile visual location recognition by fusing the inertial sensors and computer vision techniques. The main contributions are as follows: Firstly, we design an efficient vector quantization strategy by combining the Transform Coding (TC) and Residual Vector Quantization (RVQ). Our method can compress a visual descriptor into only several bytes while providing reasonable searching accuracy, which makes the managing of city scale image database directly on mobile devices come true. Secondly, we integrate the information from inertial sensors into the Vector of Locally Aggregated Descriptors (VLAD) generation and image similarity evaluation processes. Our method is not only fast enough for on-device implementation, but it also can improve the location recognition accuracy obviously. Thirdly, we also release a set of 1.295 million geo-tagged street view images with the information from inertial sensors, as well as a difficult set of query images. These resources can be used as a new benchmark to facilitate further research in the area. Experimental results prove the validity of the proposed methods for on-device mobile visual location recognition applications. [ABSTRACT FROM PUBLISHER]

Wolf Totem is not a novel which advocates 'molar' wolf characteristics such as violence, brutality and bloodthirstiness, and 'molar' wolf laws such as the law of the jungle and the law of profiting at others' expense, but a novel which reveals to readers a brand new life experience, different affects possessed by the 'molecular' wolf, and the becoming-wolf of human beings. Becoming-wolf is not to imitate the above-mentioned characteristics of the 'molar' wolf, but to see or imagine what affects the 'molecular' wolf has, and make the life force or the assumed life force possessed by the 'molecular' wolf transverse a person, so that he or she can also have those affects. Becoming-wolf is to find a line of flight between man and wolf, to get rid of all the restraints imposed by the Confucian culture on the law-abiding, abjectly obedient people, and thus regaining the force of the 'impersonal, inorganic' life, so as to become different by endless desiring productions, and enhance mankind's power. [ABSTRACT FROM AUTHOR]

A technical problem central to wireless sensor networks is location verification: how to accurately detect sensors' location information that are damaged or deliberately compromised. The need for this is evident in, e.g., battleground surveillance, where compromised sensors may incur severe damage. Previous approaches to tackling this problem are mostly centralized: a sensor node is designated as the sink, which collects location information from all nodes, conducts analysis and detects possible attacks. These, however, have to bear with prolonged response time, high energy consumption and low reliability. This paper proposes a novel location verification scheme named LPV. In contrast to previous approaches, LPV is distributed: the falsified locations of sensors are detected by conducting evaluation analysis on information of their neighboring nodes. We show that in LPV, it suffices to detect malicious nodes when each sensor only collects the information of neighboring nodes within one hops. Another advantage of LPV is, it consider the impact of localization error. We proposed a kernel-bascd approach that approximates the distribution of the localization results. We evaluate the correctness of distribution to detect localization attack. We verify, via formal analysis and experimental study in various settings, that LPV has performance comparable to centralized approaches in accurately identifying falsified sensors with higher reliability. [ABSTRACT FROM AUTHOR]

The study of cylindrical particulate internal flows has wide industrial applicability hence received much attention. This article reviews the cylindrical particulate internal flows over the past twenty years. The research is related to the cylindrical particulate flows in the straight channel, curved channel and rotational channel. Finally, several open research issues have been identified. [ABSTRACT FROM AUTHOR]

A correction to the article "Microstructure, Hardness, and Bending Strength of Carbon Nanotube-Iron Aluminide Composites" that was published in the Vol. 41, Issue 16 of the journal is presented.

During the radical phase of the Cultural Revolution in 1967-1969, China's violation of the diplomatic norms of the international community reached an unprecedented level. Two dozen British diplomats and private citizens on the mainland became de facto hostages of their host government. In response to China's hostage-taking, the British government preferred quiet diplomacy to extreme retaliation such as a rupture of diplomatic relations and economic sanctions. It focused on negotiations through minimal publicity and reciprocal gestures. But in China, the British found a culturally different negotiating partner that was obsessed with principles rather than details. Through a step-by-step negotiating approach recommended by the Sinologists in the British Mission, London was finally successful in securing the release of its detained nationals. The lesson of Britain's quiet diplomacy was a culture-sensitive approach to negotiation and the ability to separate the hostage question from the wider political and economic relationship that would facilitate the resolution of future hostage crises. [ABSTRACT FROM AUTHOR]

Industrial organic montmorillonite (IO-MMT) was characterized by X-ray diffraction (XRD) and thermogravimetry (TG). The results indicate that IO-MMT could prepare nanocomposite directly in theory. As dispersants, different nonionic surfactants were used to disperse IO-MMT. The result shows that nonionic surfactant TO-10 was selected as optimum dispersant. Then, vinyl polymer/industrial organic montmorillonite nanocomposite (PVP/IO-MMT) was prepared by vinyl polymer (PVP) and IO-MMT which dispersed in nonionic surfactant TO-10. The structure of PVP/IO-MMT nanocomposite was characterized by XRD and TEM. The result of XRD shows that the basal spacing d value of nanocomposite is 3.53 nm. The result of TEM indicates that composite was intercalated nanocomposite. Finally, PVP/IO-MMT was applied in the leather making process to examine its properties. The pickled sheepskin was tanned with 6% PVP/IO-MMT associated with 2% chromate, the shrinkage temperature of leather can be raised to 88°C. The application results show that it is an effective way to decrease the use of chromate for nanocomposites. [ABSTRACT FROM AUTHOR]

A considerable market share of electric vehicles (EVs) is expected in the near future, which leads to a transformation from gas stations to EV charging infrastructure for automobiles. EV charging stations will be integrated with the power grid to replace the fuel consumption at the gas stations for the same mobile needs. In order to evaluate the impact on distribution networks and the controllability of the charging load, the temporal and spatial distribution of the charging power is calculated by establishing mapping the relation between gas stations and charging facilities. Firstly, the arrival and parking period is quantified by applying queuing theory and defining membership function between EVs to parking lots. Secondly, the operational model of charging stations connected to the power distribution network is formulated, and the control variables and their boundaries are identified. Thirdly, an optimal control algorithm is proposed, which combines the configuration of charging stations and charging power regulation during the parking period of each individual EV. A two-stage hybrid optimization algorithm is developed to solve the reliability constrained optimal dispatch problem for EVs, with an EV aggregator installed at each charging station. Simulation results validate the proposed method in evaluating the controllability of EV charging infrastructure and the synergy effects between EV and renewable integration. [ABSTRACT FROM AUTHOR]