Santa Barbara castle is one of the largest fortified complexes of the Spanish Mediterranean coast. Set in a strategic enclave in the city of Alicante. It has been transformed over the centuries since its origin, so th...Santa Barbara castle is one of the largest fortified complexes of the Spanish Mediterranean coast. Set in a strategic enclave in the city of Alicante. It has been transformed over the centuries since its origin, so that nowadays includes numerous buildings inside its area. The fortified area contains several lines bastioned and some medieval and Muslim fronts, composed of quadrangular towers. During the years 2007 and 2008, a research team composed of members from the University of Alicante, the University of Burgos and the Polytechnic University of Catalonia has developed a study on the conservation status of the Castle. This study has been funded through research grants from thc Genemlitat Valenciana （Project GV reference 2007/150）, and an agreement with Manuel PeIAez Foundation. We have generated a 3D object of the whole, composed by clouds of millions points, through laser-scanner in order to manage the analysis of the architectural element＇s conservation status that make up the huge fortified complex. This tool reduced greatly the architectural survey work, providing an extremely accurate. They were developed through the program Pointools View, generating JPEG files, which were imported from Autocad. Later we undertook a comprehensive making of photos -- some 7,000 photographs, which we linked to the 3D object. Thus we have immediate access to the photographs of each element of the Castle from the program Pointools View with a simple click on each 3D element. The graphic representation of damages was done on screen with programs Pointools View and Autocad open simultaneously. This technique has meant better accuracy in the study of conservation status and has greatly reduced the time commitment.展开更多
This paper presents the geologic and ground control challenges that were encountered by Consol Energy＇s coal mining operations in southwestem Pennsylvania, USA. Geologic encounters, such as sandstone- to-limestone ge...This paper presents the geologic and ground control challenges that were encountered by Consol Energy＇s coal mining operations in southwestem Pennsylvania, USA. Geologic encounters, such as sandstone- to-limestone geology transition, massive sandstone channels, shale channels, pyritic rich green claystone, laminated roof, and soft floor, have significantly impacted the development and longwall mining in Consol＇s Pittsburgh Seam coal mines. Experience from different mines shows that, in the sandstone-to-limestone geology transition zone, 1.83 m high-tension, fully-grouted primary bolts employed along with 4.88 m cen- ter cable bolts at every other strap greatly improved beam building and ensured proper anchorage into the competent roof. Hydraulic fracturing of the massive sandstone was often necessary to enhance caving of the massive sandstone behind the shields to relieve pressure at the face. The presence of soft floor coupled with presence of thick floor coal and deep cover, induced excessive headgate convergence during retreat of the first right hand longwall panel. In all, it is important to explore the roof and in-seam geology in detail to delineate normal and anomalous geologic conditions prior to and during development. With diligent geologic reconnaissance, geotechnical monitoring, and assessment, site-specific geotechnical solutions have been provided to mine operations to improve safety and productivity.展开更多
The flotation process is a particle-hydrophobic surface-based separation technique. To improve the essential flotation steps of collision and attachment probabilities, and reduce the step of detachment probabilities b...The flotation process is a particle-hydrophobic surface-based separation technique. To improve the essential flotation steps of collision and attachment probabilities, and reduce the step of detachment probabilities between air bubbles and hydrophobic particles, a selectively designed cavitation venturi tube combined with a static mixer can be used to generate very high numbers of pico and nano bubbles in a flotation column. Fully embraced by those high numbers of tiny bubbles, hydrophobic particles readily attract the tiny bubbles to their surfaces. The results of column flotation of Pittsburgh No. 8 seam coal are obtained in a 5.08 cm ID and 162 cm height flotation column equipped with a static mixer and cavitation venturi tube, using kerosene as collector and MIBC as frother. Design of the experimental procedure is combined with a statistical two-stepwise analysis to determine the optimal operating conditions for maximum recovery at a specified grade. The effect of independent variables on the responses has been explained. Combustible material recovery of 85–90% at clean coal product of 10–11% ash is obtained from feed of 29.6% ash, with a much-reduced amount of frother and collector than that used in conventional column flotation. The column flotation process utilizing pico and nano bubbles can also be extended to the lower limit and upper limit of particle size ranges, minus 75 lm and 300–600 lm, respectively, for better recovery.展开更多
By introducing a kind of maximal operator of the fractional order associated with the mean Luxemburg norm and using the technique of the sharp function,the weak type LlogL estimates for the commutators of the fraction...By introducing a kind of maximal operator of the fractional order associated with the mean Luxemburg norm and using the technique of the sharp function,the weak type LlogL estimates for the commutators of the fractional integral operator and the related maximal operator are established.展开更多
CUBA The U.S.cruise ship Adonia arrives in Havana on May 2 with 704 passengers on board,becoming the first such vessel to dock in Cuba from the United States since 1978RUSSIA Performers wearing work clothes attend a r...CUBA The U.S.cruise ship Adonia arrives in Havana on May 2 with 704 passengers on board,becoming the first such vessel to dock in Cuba from the United States since 1978RUSSIA Performers wearing work clothes attend a rally in St.展开更多
文摘Santa Barbara castle is one of the largest fortified complexes of the Spanish Mediterranean coast. Set in a strategic enclave in the city of Alicante. It has been transformed over the centuries since its origin, so that nowadays includes numerous buildings inside its area. The fortified area contains several lines bastioned and some medieval and Muslim fronts, composed of quadrangular towers. During the years 2007 and 2008, a research team composed of members from the University of Alicante, the University of Burgos and the Polytechnic University of Catalonia has developed a study on the conservation status of the Castle. This study has been funded through research grants from thc Genemlitat Valenciana （Project GV reference 2007/150）, and an agreement with Manuel PeIAez Foundation. We have generated a 3D object of the whole, composed by clouds of millions points, through laser-scanner in order to manage the analysis of the architectural element＇s conservation status that make up the huge fortified complex. This tool reduced greatly the architectural survey work, providing an extremely accurate. They were developed through the program Pointools View, generating JPEG files, which were imported from Autocad. Later we undertook a comprehensive making of photos -- some 7,000 photographs, which we linked to the 3D object. Thus we have immediate access to the photographs of each element of the Castle from the program Pointools View with a simple click on each 3D element. The graphic representation of damages was done on screen with programs Pointools View and Autocad open simultaneously. This technique has meant better accuracy in the study of conservation status and has greatly reduced the time commitment.
文摘This paper presents the geologic and ground control challenges that were encountered by Consol Energy＇s coal mining operations in southwestem Pennsylvania, USA. Geologic encounters, such as sandstone- to-limestone geology transition, massive sandstone channels, shale channels, pyritic rich green claystone, laminated roof, and soft floor, have significantly impacted the development and longwall mining in Consol＇s Pittsburgh Seam coal mines. Experience from different mines shows that, in the sandstone-to-limestone geology transition zone, 1.83 m high-tension, fully-grouted primary bolts employed along with 4.88 m cen- ter cable bolts at every other strap greatly improved beam building and ensured proper anchorage into the competent roof. Hydraulic fracturing of the massive sandstone was often necessary to enhance caving of the massive sandstone behind the shields to relieve pressure at the face. The presence of soft floor coupled with presence of thick floor coal and deep cover, induced excessive headgate convergence during retreat of the first right hand longwall panel. In all, it is important to explore the roof and in-seam geology in detail to delineate normal and anomalous geologic conditions prior to and during development. With diligent geologic reconnaissance, geotechnical monitoring, and assessment, site-specific geotechnical solutions have been provided to mine operations to improve safety and productivity.
基金provided by West Virginia State Coal and Energy Research Bureau (CERB)the Department of Mining Engineering,West Virginia University
文摘The flotation process is a particle-hydrophobic surface-based separation technique. To improve the essential flotation steps of collision and attachment probabilities, and reduce the step of detachment probabilities between air bubbles and hydrophobic particles, a selectively designed cavitation venturi tube combined with a static mixer can be used to generate very high numbers of pico and nano bubbles in a flotation column. Fully embraced by those high numbers of tiny bubbles, hydrophobic particles readily attract the tiny bubbles to their surfaces. The results of column flotation of Pittsburgh No. 8 seam coal are obtained in a 5.08 cm ID and 162 cm height flotation column equipped with a static mixer and cavitation venturi tube, using kerosene as collector and MIBC as frother. Design of the experimental procedure is combined with a statistical two-stepwise analysis to determine the optimal operating conditions for maximum recovery at a specified grade. The effect of independent variables on the responses has been explained. Combustible material recovery of 85–90% at clean coal product of 10–11% ash is obtained from feed of 29.6% ash, with a much-reduced amount of frother and collector than that used in conventional column flotation. The column flotation process utilizing pico and nano bubbles can also be extended to the lower limit and upper limit of particle size ranges, minus 75 lm and 300–600 lm, respectively, for better recovery.
基金This work was supported by 973 Project of China, the National Natural Science Foundation of China (Grant No. 19971010) and DPFIHEC (Grant No. 98002703).
文摘By introducing a kind of maximal operator of the fractional order associated with the mean Luxemburg norm and using the technique of the sharp function,the weak type LlogL estimates for the commutators of the fractional integral operator and the related maximal operator are established.
文摘CUBA The U.S.cruise ship Adonia arrives in Havana on May 2 with 704 passengers on board,becoming the first such vessel to dock in Cuba from the United States since 1978RUSSIA Performers wearing work clothes attend a rally in St.
