面向智慧旅游的游客数据库设计与实现

游客数据是智慧旅游的关键基础数据,本文深入分析了游客个性化的智慧旅游需求特点,归纳凝练了游客的偏好和交互等信息,设计了一种实用的游客数据库结构,支持相关动态信息的实时接入与动态更新,开发了典型智慧旅游原型系统,并实验验证了游客数据库的有效性。     

测量监测技术在高层钢结构施工中的应用实践

本文结合大连期货大厦高层钢结构施工放样工程论述了高层钢结构主体施工控制和监测的工艺方法,具体介绍了首层控制网建立,内控点投测、轴线控制,标高控制、标高传递的步骤,以及钢柱扭转、错位、垂直度纠正的方法,对其它高层钢结构施工有参考价值。     

基于腹地划分的中国城市群空间影响范围识别

城市群空间影响范围的界定是认清城市群内中心城市与腹地、城市与城市间相互关联的基础。采用主成分分析法计算中国287个地级及以上城市的结节性指数,利用累积耗费距离法和k阶数据场,综合测度了交通可达性与空间场能,根据场强"取大"原则对城市腹地进行了划分,依据城市腹地范围界定了城市群的空间影响范围。结果表明:①中国地级以上城市最大和最小结节性指数相差157.53倍,城市平均可达时间为193.43 min,场能平均值为5 412,最大和最小城市腹地相差3 751倍;②23个城市群中,空间影响范围最大的是北疆城市群,空间平均场强最大的是中原城市群;③城市群在空间上呈现为发育程度不同的"11+9+3"的分布格局和逆时针90°旋转的"β"型城市群连绵带发展格局;④基于腹地划分的城市群空间影响范围充分考虑了现实的交通网络和地形地貌特点,实现了对广域空间范围内城市腹地范围和城市群空间影响范围的定量测度。     

辅助微分方程完全匹配层在声波方程数值模拟中的应用

在地震波数值模拟中,为提高算法精度,需要使用高阶时间更新格式,而普通的非分裂完全匹配层（PML）吸收边界局限于低阶时间格式。辅助微分方程完全匹配层（ADE PML）是一种可以适应任意阶时间格式的非分裂完全匹配层技术,且可以直接应用复频移拉伸算子以提高PML在高角度入射时的效果。作者将ADE PML应用于声波方程四阶Runge Kutta时间格式的数值模拟中,对其吸收效能进行了检验。数值模拟表明,复频移ADE PML在高角度入射时表现优于非复频移ADE PML。另外,不同辅助变量更新格式的吸收效果存在微小差异,显格式下计算结果与解析解吻合较好。长时间能量衰减计算表明ADE PML可以稳定至2 × 10⁵时间步。     

An Approach for Modeling Rock Discontinuous Mechanical Behavior Under Multiphase Fluid Flow Conditions

In this paper, the two computer codes TOUGH2 and RDCA (for “rock discontinuous cellular automaton”) are integrated for coupled hydromechanical analysis of multiphase fluid flow and discontinuous mechanical behavior in heterogeneous rock. TOUGH2 is a well-established code for geohydrological analysis involving multiphase, multicomponent fluid flow and heat transport; RDCA is a numerical model developed for simulating the nonlinear and discontinuous geomechanical behavior of rock. The RDCA incorporates the discontinuity of a fracture independently of the mesh, such that the fracture can be arbitrarily located within an element, while the fluid pressure calculated by TOUGH2 can be conveniently applied to fracture surfaces. We verify and demonstrate the coupled TOUGH–RDCA simulator by modeling a number of simulation examples related to coupled multiphase flow and geomechanical processes associated with the deep geological storage of carbon dioxide—including modeling of ground surface uplift, stress-dependent permeability, and the coupled multiphase flow and geomechanical behavior of fractures intersecting the caprock.     

桩筏基础下地基土的荷载传递特性

桩筏基础由桩和筏组成一种联合基础，筏将大部分总荷载传递给桩，同时其本身也承担总荷载的一部分。因此，充分认识桩筏基础对上部荷载向地基土的传递特性是非常必要的。该文提出一个桩筏基础传递荷载的计算模型，模型考虑了桩的布置形式对地基接触压力的影响，同时还考虑了桩的受荷过程中的变化特性，并详细分析了桩与筏之间的荷载分配问题。     

An approach to studying heavy metal pollution caused by modern city development in Nanjing, China

 Nanjing is currently one of the fastest developing regions in terms of construction and economy in China. Heavy metal pollution is becoming more serious with the expansion of production and life scales. Four environmental units (highway, refinery, rubbish dumps associated with human daily life, and shoal of the Yangtse River) were selected from the region according to the geneses of the pollution to study and evaluate the distribution and mechanism of the contamination, the speciations of the polluting elements, and the geneses of the pollution in the soils and sediments. The purposes of the study are to understand generally the current situation and the cause of the pollution, and to provide a scientific basis to prevent and solve the pollution problem. At the same time, it would be helpful to probe the effective way of studying heavy metal pollution resulting from the development of modern cities and to accumulate data. It is indicated by the study that the heavy metals contained in the soil of the environmental unit of the highway are Pb, Co and Cr; in the soil of the refinery Cr, V, Pb, Ni, and Co; in the soil of the rubbish plot Co, Cu, and Sb; in the sediments of the shoal Pb, Co, Cu, and Ni. Fe-Mn oxide is given the first place to the speciations in polluting heavy metals transmitted by air. Carbonate is more in speciations of polluting heavy metals transmitted by water than in speciations of the metals transmitted by air. In the ten elements studied, Pb is most directly poisonous to the plants in the region; Co and Cu are the next, and Ni is the least. Heavy metal pollution has been occurring in the soils and sediments of the region and the situation will worsen if some effective measures are not taken. Received: 18 October 1997 · Accepted: 3 February 1998     

GPS授时地震仪走时误差校正

受制造成本和工艺的限制,GPS授时地震仪中的守时晶振不可避免地会有频率误差,继而在数据采集过程中,随着采集时间的增加,各台站之间会出现采集不同步现象。介绍了Akima分段多项式插值重采样方法及其在GPS授时地震仪时间校正中的应用。通过对理论数据与实际数据的Akima插值重采样试验表明,Akima插值重采样方法可应用于GPS授时地震仪走时误差校正,是一种简便、高效、保形性好的插值重采样方法。     

埋藏岩溶洞穴垮塌深度定量图版及其在碳酸盐岩缝洞型储层地质评价预测中的意义

通过对岩溶洞穴垮塌的岩石力学原理及塔里木盆地奥陶系实钻资料的分析,基本明确了洞穴埋藏垮塌的控制因素是岩石抗弯强度、洞穴尺度、洞穴距风化暴露面的距离等,并得到了洞穴垮塌深度的定量图版。该图版对于钻前预测现今埋藏于地下的碳酸盐岩洞穴是否已经垮塌、洞穴埋藏演化史精确恢复以及对裂缝—洞穴型储层的评价预测具有较强的实践意义。     

Five new E′ centers and their 29Si hyperfine structures in electron-irradiated α-quartz

Single-crystal electron paramagnetic resonance (EPR) spectra of fast-electron-irradiated quartz, after annealing at 120 and 200°C, reveal five new E′ type centers, herein labeled E ₅^￠ , E ₆^￠ , E ₇^￠ , E ₈^￠ , \textand E ₉^￠ E_{ 5}^{\prime } ,\,E_{ 6}^{\prime } ,\,E_{ 7}^{\prime } ,\,E_{ 8}^{\prime } ,\,{\text{and}}\,E_{ 9}^{\prime } . Centers E ₅^￠ , E ₇^￠ , \textand E ₉^￠ E_{ 5}^{\prime } ,\,E_{ 7}^{\prime } ,\,{\text{and}}\,E_{ 9}^{\prime } are characterized by the orientations of the unique principal g and A(²⁹Si) axes close to a short Si–O bond direction, hence representing new variants of the well-established E ₁^￠ E_{ 1}^{\prime } center. Centers E ₆^￠ E_{ 6}^{\prime } and E ₈^￠ E_{ 8}^{\prime } have the orientations of the unique principal g and A(²⁹Si) axes approximately along a long Si–O bond direction, similar to the E ₂^￠ E_{ 2}^{\prime } centers. Therefore, these new E′ type centers apparently arise from the removal of different oxygen atoms and represent variable local distortions around the oxygen vacancies.