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91.
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
92.
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
93.
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
94.
95.
96.
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
97.
Keun HC Beckonert O Griffin JL Richter C Moskau D Lindon JC Nicholson JK 《Analytical chemistry》2002,74(17):4588-4593
Cryogenic probe technology can significantly compensate for the inherently low sensitivity of natural abundance 13C NMR spectroscopy. This now permits its routine use in NMR spectroscopy of biofluids, such as urine or plasma, with acquisition times that enable a high throughput of samples. Metabonomic studies often generate numerous samples in order to characterize fully the time-dependent biochemical response to stimuli, but until now, they have been largely conducted using 1H NMR spectroscopy because of its high sensitivity and hence efficient data acquisition. Here, we demonstrate that information-rich 13C NMR spectra of rat urine can be obtained using appropriately short acquisition times suitable for biochemical samples when using a cryogenic probe. Furthermore, these data were amenable to automated pattern recognition analysis, which produced a profile of the metabolic response to the model hepatotoxin hydrazine that was consistent with earlier studies. Thus, a new source of detailed and complementary information is available to metabonomics using cryogenic probe 13C NMR spectroscopy. 相似文献
98.
Lenoble J Martin T Blumthaler M Philipona R Albold A Cabot T de La Casinière A Gröbner J Masserot D Müller M Pichler T Seckmeyer G Schmucki D Touré ML Yvon A 《Applied optics》2002,41(9):1629-1639
A measurement campaign was organized in March 1999 in the Bavarian Alps as part of the European project, Characteristics of the UV Radiation Field in the Alps (CUVRA), to analyze the effect of altitude, aerosols, and snow cover on ground-level UV spectral irradiance. We present the results of simultaneous measurements of aerosol optical depth (AOD) made at various sites on two cloudless days in March 1999. The two days exhibited different aerosol conditions. Results derived from spectral measurements of UV irradiance are compared with data from filter radiometer measurements made at discrete wavelengths extending from the UV to the near IR. The different methods generated values for the AOD that were in good agreement. This result confirms that one can use either method to retrieve the AOD with an uncertainty of approximately 0.03-0.05. On 18 March, high turbidity was observed at low altitude (400-nm AOD approximately 0.5 at 700 m above sea level), and the AOD decreased regularly with altitude; on 24 March, the turbidity was much less (0.11 at 700 m above sea level). On both days very low AODs (0.05-0.09) were measured at 3000 m above sea level. The spectral dependence of the AOD is often parameterized by the angstrom relationship; the alpha parameter is generally difficult or impossible to retrieve from spectral measurements because of the relatively narrow wavelength range (320-400 nm), and only one of the spectro-radiometers used during the campaign permits this retrieval. In most cases, during this field campaign, alpha was found by filter sunphotometers to be 1.1-1.5. 相似文献
99.
Estefania Argente Vicente Julian Vicente Botti 《Electronic Notes in Theoretical Computer Science》2006,150(3):55-71
Organizational models have been recently used in agent theory for modeling coordination in open systems and to ensure social order in multi-agent system applications. In this paper, we propose the employment of Organization Theory for the analysis and design of multiagent systems. Thus, we first discuss the current state of the art of organization-oriented multiagent system methods, placing emphasis on their organizational features. We also review human organizational structures, and we propose several guidelines for implementing agent organizations by means of Organization Theory. Our final aim is to employ well-known human organizational structures to develop multiagent systems. 相似文献
100.
Volker Willert Julian Eggert Jürgen Adamy Raphael Stahl Edgar K?rner 《IEEE transactions on systems, man, and cybernetics. Part B, Cybernetics》2006,36(5):982-994
This paper proposes a biologically inspired and technically implemented sound localization system to robustly estimate the position of a sound source in the frontal azimuthal half-plane. For localization, binaural cues are extracted using cochleagrams generated by a cochlear model that serve as input to the system. The basic idea of the model is to separately measure interaural time differences and interaural level differences for a number of frequencies and process these measurements as a whole. This leads to two-dimensional frequency versus time-delay representations of binaural cues, so-called activity maps. A probabilistic evaluation is presented to estimate the position of a sound source over time based on these activity maps. Learned reference maps for different azimuthal positions are integrated into the computation to gain time-dependent discrete conditional probabilities. At every timestep these probabilities are combined over frequencies and binaural cues to estimate the sound source position. In addition, they are propagated over time to improve position estimation. This leads to a system that is able to localize audible signals, for example human speech signals, even in reverberating environments. 相似文献