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51.
以澳门天主教堂为研究对象,探索原本在时间、空间和性质上差异极大的两种文明之间的和谐共存。通过梳理教堂的建造背景,分析教堂的典型案例,进而归纳教堂的建筑特点,发现澳门教堂既是东方建筑,又是西方建筑,既满怀必不可免的“出世”情结,也拥有无法超脱的“人间”关怀。 相似文献
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53.
生物滞留系统对城市公路径流的治理作用 有无内部蓄水层设计的对比研究 总被引:2,自引:0,他引:2
研究评价了两种生物滞留系统对于综合公路径流的治理作用。该实验位于炎热干旱的德州布赖恩市德州农工大学(TAMU)河滨校区,实验者制作了5个大型的生态滞留装置,以便于在底部形成61cm深的内部蓄水(IWS)层,分别对有无内部蓄水层设计的生物滞留系统进行了模拟真实径流水量和水质的合成公路径流测试。比较结果表明,内部蓄水(IWS)层能减少洪峰流量、延长径流滞留时间,同时还显著提高了对铜、悬浮固体以及氮和磷的去除效果。尽管内部蓄水层改善了公路径流的治理,但在炎热干旱地区使用内部蓄水层持水仍面临巨大挑战,因为大量的水会通过蒸发而散失掉。接下来的研究需要制定关于内部蓄水层在炎热干旱地区应用的进一步方针。 相似文献
54.
Efforts have been made to develop a promising anode material with a novel composition for sodium-ion batteries (SIBs).In this study,the sodium-ion storage mecha... 相似文献
55.
This paper provides meta‐analyses of the published findings relating the respiratory health of occupants of schools with visible dampness, water damage, visible mold, and/or mold odor. Random effects models were used to develop central estimates and confidence limits for the associations of respiratory health effects with school dampness and mold. Eleven studies, all with cross‐sectional designs, were included in the meta‐analyses; however, analyses for some health outcomes were based on as few as four studies. Analyses were performed using data from adults and children combined, using only data from children, and using data from adults and children after excluding two studies. The central estimates of odds ratios from the meta‐analyses were consistently above unity. The evidence of adverse health effects was strongest for cough and wheeze, which had confidence limits excluding unity in some or all analyses. The odds ratios of 1.32 for cough and 1.68 for wheeze suggest moderate increases in health risk. Studies not included in the meta‐analyses provide additional evidence that dampness and mold in schools are associated with adverse health outcomes. These meta‐analyses and the published literature not included in the meta‐analyses suggest that dampness and mold in schools are associated with adverse respiratory health effects. 相似文献
56.
57.
In Chan Kim 《Journal of Mechanical Science and Technology》2000,14(1):84-92
A new bounce back boundary method of the second order in error is proposed for the lattice Boltzmann fluid simulation. This new method can be used for the arbitrarily irregular lattice geometry of a non-slip boundary. The traditional bounce back boundary condition for the lattice Boltzmann simulation is of the first order in error. Since the lattice Boltzmann method is the second order scheme by itself, a boundary technique of the second order has been desired to replace the first order bounce back method. This study shows that, contrary to the common belief that the bounce back boundary condition is unilaterally of the first order, the second order bounce back boundary condition can be realized. This study also shows that there exists a generalized bounce back technique that can be characterized by a single interpolation parameter. The second order bounce back method can be obtained by proper selection of this parameter in accordance with the detailed lattice geometry of the boundary. For an illustrative purpose, the transient Couette and the plane Poiseuille flows are solved by the lattice Boltzmann simulation with various boundary conditions. The results show that the generalized bounce back method yields the second order behavior in the error of the solution, provided that the interpolation parameter is properly selected. Coupled with its intuitive nature and the ease of implementation, the bounce back method can be as good as any second order boundary method. 相似文献
58.
In this paper, an on-line trained neural network controller is applied to control the flow rate of a process control rig. The neural controller replaces a conventional controller in the forward path. The overall performance of this controller is compared with that of a PID controller in the presence of noise and non-linearity. It is shown that as the non-linearity is added to the system, the PID controller cannot track the set-point changes, however, the neural controller copes well under various conditions. 相似文献
59.
Chuang MT Fu JS Jang CJ Chan CC Ni PC Lee CT 《The Science of the total environment》2008,406(1-2):168-179
Aerosol is frequently transported by a southward high-pressure system from the Asian Continent to Taiwan and had been recorded a 100% increase in mass level compared to non-event days from 2002 to 2005. During this time period, PM2.5 sulfate was found to increase as high as 155% on event days as compared to non-event days. In this study, Asian emission estimations, Taiwan Emission Database System (TEDS), and meteorological simulation results from the fifth-generation Mesoscale Model (MM5) were used as inputs for the Community Multiscale Air Quality (CMAQ) model to simulate a long-range transport of PM2.5 event in a southward high-pressure system from the Asian Continent to Taiwan. The simulation on aerosol mass level and the associated aerosol components were found within a reasonable accuracy. During the transport process, the percentage of semi-volatile PM2.5 organic carbon in PM2.5 plume only slightly decreased from 22-24% in Shanghai to 21% near Taiwan. However, the percentage of PM2.5 nitrate in PM2.5 decreased from 16-25% to 1%. In contrast, the percentage of PM2.5 sulfate in PM2.5 increased from 16-19% to 35%. It is interesting to note that the percentage of PM2.5 ammonium and PM2.5 elemental carbon in PM2.5 remained nearly constant. Simulation results revealed that transported pollutants dominate the air quality in Taipei when the southward high-pressure system moved to Taiwan. Such condition demonstrates the dynamic chemical transformation of pollutants during the transport process from continental origin over the sea area and to the downwind land. 相似文献
60.
Comparisons of commuter's exposure to particulate matters while using different transportation modes 总被引:2,自引:0,他引:2
This study compared commuters' exposures to particulate matter (PM) while using motorcycles, cars, buses, and the mass rapid transit (MRT) on the same routes in Taipei, Taiwan. Motorcycle commuters who had the shortest travel time (28.4+/-4.2 min) were exposed to the highest concentrations of PM(10) (112.8+/-38.3 microg/m(3)), PM(2.5) (67.5+/-31.3 microg/m(3)), and PM(1.0) (48.4+/-24.7 microg/m(3)) among four commuting modes. By contrast, car commuters were exposed to the lowest PM concentrations and had the second shortest travel time among them. Motorcycle commuters' high trip-averaged PM concentrations and bus commuters' long commuting time (43.1+/-5.1 min) resulted in their high whole-trip PM exposures. Size fractions of PM were relatively consistent across PM exposures of the four commuting modes with fine particles (PM(2.5)) contributing to 53-60% of PM(10) and submicron particle (PM(1)) contributing to 39-43% of PM(10). Motorcycles idled at traffic lights and bus doors opened at stops increased commuters' PM exposures. Fixed-site monitoring data explained well the variation of whole-trip PM(10) exposure of car (r(2)=0.63) and MRT (r(2)=0.52) commuters, and of whole-trip PM(2.5) exposure of car (r(2)=0.76), MRT (r(2)=0.73) and motorcycle (r(2)=0.64) commuters in regression analyses. The coefficients (slopes) of regression between fixed-site monitoring data and PM(2.5) exposures were less than 1 for car and MRT commuters but greater than 1 for motorcycle commuters. In conclusion, proximity to traffic emissions contributes to a person's high PM exposure during his or her daily commute. This proximity occurs when people use motorcycles on roads and when bus/MRT commuters walk or wait along commuting routes. Fixed-site air monitoring data can under-estimate motorcycle commuters' PM(2.5) exposures but over-estimate car and MRT commuters' PM(2.5) exposures. 相似文献