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Rock breaking by double hydraulic hammers has a wide application prospect in hard-rock roadway excavation because of its environmental protection and strong rock-breaking ability, but the optimal spacing under double-indenter synchronous impact is not clear. Based on the rock-breaking experimental system under double-indenter synchronous impact established by combining a detachable double-indenter device and Hopkinson pressure bar, the impact tests of three kinds of rocks are carried out, and a theoretical model of specific energy consumption is derived to determine the optimal spacing. The results show that when the indenter spacing is 28 mm, 42 mm, and 14 mm, respectively--that is, when the cross section of the fragmentation crater is in the shape of a "peanut" with a fine middle and two large ends--the concrete, limestone, and sandstone specimens reach the minimum specific energy consumption, which is reduced by 22.55 %, 30.60 %, and 11.85 %, respectively, compared with single-indenter impact. The theoretical model, which explains and verifies the experimental phenomena and results well, can be divided into four zones, and the optimal spacing is in Zone III. The research can be helpful for actual hard-rock tunneling under double hydraulic hammers. [ABSTRACT FROM AUTHOR]

Against the background that the top-level semantic framework of Chinese traditional culture is not comprehensive and unified, this study aims to preserve and disseminate cultural heritage information about Chinese traditional culture through the development of a domain ontology which is constructed from ancient books. A combination of top-down and bottom-up approaches was used to construct the ontology for Chinese traditional culture (CTCO). An investigation of historians' needs, and LDA topic clustering model were conducted, understanding the specific needs of historians, collecting the topic, concepts and relationships. CIDOC CRM was reused to construct the basic framework of CTCO. Ontology structure and function were adopted to evaluate the effectiveness of CTCO. Evaluation results show that the ontology meets all the quality criteria of OntoMetrics, and the experts agreed on content representation (average score = 4.30). CTCO contributes to the organization of traditional Chinese culture and the construction of related databases. The study also forms a common path and puts forward proposals for the construction of domain ontology, which has great social relevance. [ABSTRACT FROM AUTHOR]

With the continuous improvement of the economy and people's living standards, forest tourism has become an important form of tourism that has the greatest development potential. Guided by the theory of sustainable development, this thesis draws on the theoretical research results of ecotourism, external effects, tourism management, national parks, etc., studies the forest park management system, tourism development model, and development and construction ideas, and then summarizes forest tourism resources. Aiming at the shortcomings of the cost-route optimization of the axle-spoke tourism network design problem, this article introduces the segmented cost function to propose the problem of the axle-spoke tourism network design. At the same time, a mixed integer programming model for the problem is established, a greedy algorithm for solving the problem is designed, and an example provided by the AP data package is used as a platform to perform a calculation experiment on the model. Taking the AP2-6 network as a reference object, the superiority of the piecewise cost function over the two-stage cost function is analyzed. [ABSTRACT FROM AUTHOR]

Titanium dioxide (TiO2) nanotubes were obtained via an anodic oxidation process. Furthermore, a graphene oxide was formed by means of an improved Hummer's Method, and the corresponding reduced graphene oxide was obtained via reduction under concentrated-alkali conditions. The resulting RGO/TiO2 nanotube composite was synthesized using Anodic Electrochemical Deposition Techniques. Carbon dioxide was photoelectrocatalytically reduced to ethanol with the RGO/TiO2 nanotube composite as the cathode and platinum as the anode. The Ti02 nanotubes were characterized via scanning electron microscopy (SEM), and RGO was characterized via SEM as well as transmission electron microscopy (TEM). Moreover, the composite was characterized using SEM, energy dispersive spectroscopy, as well as X-ray diffraction, and gas chromatography was used to determine the yield of ethanol. The results showed that, through Anodic Electrochemical Deposition Techniques, an RGO/TiO2 nanotube composite can be synthesized by applying a 20 V reaction voltage for 6 h. Using a 2 % aqueous sodium bicarbonate solution as the electrolyte, the carbon dioxide was reduced to ethanol by applying a 1.5 V reaction voltage for 4 h under ultraviolet light. In addition, gas chromatography revealed an ethanol yield of 185.08 nmol/cm² cat. [ABSTRACT FROM AUTHOR]