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Julian Canto-Perello Jorge Curiel-Esparza Vicente Calvo 《Tunnelling and Underground Space Technology incorporating Trenchless Technology Research》2009,24(2):185-189
Utilities are an integral component of the total transportation network comprising highways, railways, airways, and waterways, as well as pipelines, wires, and cables that transport people, goods, and public services. The perennial dilemma of mutual interference between utility lines and transportation networks could be minimised making use of utility tunnel systems. Utilidors most striking feature is that they house several types of power, water, sewage, communications, gas and other statutory services in an easily accessible space. Placing utilities in tunnels under public rights-of-way reduces the continual cutting of pavements resulting from utility burial practices and facilitates the installation, inspection, replacement, and maintenance operations. Utility tunnels and transportation networks may not be compatible at transmission levels. Highway systems are generally planned to avoid high-density areas insofar as is possible. However, where the location of utility networks coincides sufficiently with the highway routes, the situation becomes more favourable to the utility tunnel concept. This paper discusses how compatibility of utility system networks with highway system networks could be greatly improved by appropriate attention to utilidor systems in urban planning. A sustainable approach to the dilemma of where to locate utilities in urban streets and highways has become urgent as the need for services expands in our modern cities. Interference between the safety and flow of highway traffic and utility tunnel operation could be a problem unless adequate measures are undertaken. 相似文献
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Julian Salas Marina Alvarez Gabriel Gomez Janer Veras 《Building Research & Information》2013,41(6):367-376
In a previous issue the Instituto Eduardo Torroja in Spain described the development of lightweight panels made from ordinary Portland cement and rice husk ash (RHA). This paper discusses the crucial effect of the curing régime on compressive strength with temperatures maintained at 30C and relative humidity at 80 percent. 相似文献
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Congling Yin Guobao Li Tounan Jin Julian Tao James W. Richardson Chun-K. Loong Fuhui Liao Jianhua Lin 《Journal of Alloys and Compounds》2010,489(1):152-156
A new compound Ba5Sn1.1Mn3.9O15 has been synthesized at 1300 °C by solid-state reaction. The structure was characterized by X-ray, electron and neutron diffraction methods. Ba5Sn1.1Mn3.9O15 crystallizes in hexagonal space group P63/mmc with a = 5.717 Å and c = 23.534 Å. The magnetic measurement reveals that Ba5Sn1.1Mn3.9O15 has a spin glass transition at 7 K. 相似文献
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Simon Harding Julian F. Miller Wolfgang Banzhaf 《Genetic Programming and Evolvable Machines》2010,11(3-4):397-439
Self-modifying Cartesian Genetic Programming (SMCGP) is a general purpose, graph-based, developmental form of Genetic Programming founded on Cartesian Genetic Programming. In addition to the usual computational functions, it includes functions that can modify the program encoded in the genotype. This means that programs can be iterated to produce an infinite sequence of programs (phenotypes) from a single evolved genotype. It also allows programs to acquire more inputs and produce more outputs during this iteration. We discuss how SMCGP can be used and the results obtained in several different problem domains, including digital circuits, generation of patterns and sequences, and mathematical problems. We find that SMCGP can efficiently solve all the problems studied. In addition, we prove mathematically that evolved programs can provide general solutions to a number of problems: n-input even-parity, n-input adder, and sequence approximation to π. 相似文献