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Adapting keyword search to XML data has been attractive recently, generalized as XML keyword search (XKS). One of its key tasks is to return the meaningful fragments as the result.[1] is the latest work following this trend, and it focuses on returning the fragments rooted at SLCA (Smallest LCA -Lowest Common Ancestor) nodes. To guarantee that the fragments only contain interesting nodes, [1] proposes a contributor-based filtering mechanism in its MaxMatch algorithm. However, the filtering mechanism is not sufficient. It will commit the false positive problem (discarding interesting nodes) and the redundancy problem (keeping uninteresting nodes).In this paper, our interest is to propose a framework of retrieving meaningful fragments rooted at not only the SLCA nodes, but all LCA nodes. We begin by introducing the concept of Relaxed Tightest Fragment (RTF) as the basic result type. Then we propose a new filtering mechanism to overcome those two problems in MaxMatch. Its kernel is the concept of valid contributor, which helps to distinguish the interesting children of a node. The new filtering mechanism is then to prune the nodes in a RTF which are not valid contributors to their parents. Based on the valid contributor concept, our ValidRTF algorithm not only overcomes those two problems in MaxMatch, but also satisfies the axiomatic properties deduced in [1] that an XKS technique should satisfy. We compare ValidRTF with MaxMatch on real and synthetic XML data. The result verifies our claims, and shows the effectiveness of our validcontributor-based filtering mechanism.

The pulp and paper industry is one of the most energy-intensive industries worldwide. An energy audit is a primary step toward improving energy efficiency at the facility level. This paper describes a plant-wide energy audit aimed at identifying energy conservation and carbon dioxide (CO 2 ) mitigation opportunities at a paper mill in Guangdong province, China. We describe the energy audit methods, relevant Chinese standards, methods of calculating energy and carbon indicators, baseline energy consumption and CO 2 emissions of the audited paper mill, and nine energy-efficiency improvement opportunities identified by the audit. For each of the nine options, we evaluate the energy conservation and associated CO 2 mitigation potential. The total technical energy conservation potential for these nine opportunities is 967.8 terajoules (TJ), and the total CO 2 mitigation potential is equal to 93,453 tonnes CO 2 annually, representing 14.4 percent and 14.7 percent, respectively, of the mill's total energy consumption and CO 2 emissions during the audit period.

The pulp and paper industry accounts for approximately 5 percent of total industrial energy consumption and contributes 2 percent of direct carbon dioxide (CO 2 ) emissions from industries. World paper and paperboard demand and production are increasing significantly, leading to an increase in this sector's energy use and CO 2 emissions. Although current studies identify a wide range of energy-efficiency technologies that have already been commercialized for the pulp and paper industry, information is limited or scattered regarding new energy-efficiency technologies that are not yet fully commercialized. Development of emerging or advanced energy-efficiency technologies and their deployment in the market will be crucial for this industry's midand longterm energy saving and climate change mitigation strategies. This paper compiles available information on energy savings, environmental and other benefits, costs, and commercialization status for 25 emerging technologies to reduce the energy use and CO 2 emissions. The purpose is to provide a well-structured comprehensive review on these emerging energy-efficiency technologies for engineers, researchers, investors, policy makers, pulp and/or paper companies, and other interested parties.

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We propose a facile and effective route for large-scale fabrication of a superhydrophobic thermal energy storage (STES) sprayable coating with heat storage capacity and superhydrophobicity based on polydivinylbenzene (PDVB) nanotubes (NTs). Herein, the STES coating was applied on wood by convenient spraying, and the PDVB NTs played an integral role in the STES coating. On the one hand, PDVB NTs act as a support material to adsorb and prevent the leakage of industrial paraffin wax (IPW) because of the lipophilicity of PDVB NTs and the capillary forces between the PDVB NTs and the melted IPW. By improving the specific surface area of PDVB NTs, the PDVB NTs show a great loading capacity for IPW (78.29 wt %), which contributes to the large latent heat of fusion (119.6 J/g) of the STES coating. Moreover, the STES coating possesses good thermal reliability and thermal energy conversion ability. On the other hand, PDVB NTs as a framework combine with fluorine-containing SiO2 nanoparticles to form a hierarchical structure of the STES coating, which endows the STES coating satisfactory water-repellent properties with a water contact angle of 157.7° and a sliding angle of 1.3°. In addition, the coating possesses outstanding resistance against corrosive liquids and UV irradiation as well as has self-cleaning properties. Surprisingly, the knife scratch test confirms that even if the surface of the STES coating is destroyed, the revealed surface will also present superhydrophobicity. Simultaneously, the STES coating has good adhesion strength that maintains excellent superhydrophobicity under ultrasonic treatment, finger rubbing, and severe friction due to the contribution of ethyl α-cyanoacrylate. Therefore, the STES coating has both great phase change behaviors and remarkable superhydrophobic properties to resist the erosion of the natural environment, which will pave the way for its application in practice.

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