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1.
In this study, households’ decisions on reconstruction of damaged houses were modeled, using questionnaire data in Japan.
Characteristics of households’ decisions were investigated using parameter estimation results. The effects of subsidizing
policy were evaluated as follows. First, subsidy for rebuilding may be effective for the households whose houses were heavily
damaged. Second, there is a possibility that subsidy accelerated rebuilding of houses by the households having children. Third,
subsidy for rebuilding may not be effective for elderly people’s households and households in depopulated areas. 相似文献
2.
边境区位及其再创造初探 总被引:2,自引:0,他引:2
传统区位理论认为,国家边界降低了边境地区中心地的“中心性”,分割了中心地市场区,使边界两侧的经济活动交往的空间和时间距离加大。当前,随着经济全球化、区域经济一体化以及企业组织、企业行为变革和各边境地区区域和地方组织的积极参与等动力机制的作用,跨边界经济合作过程中,边境地区进行着边境区位的再创造。本文对传统区位理论有关边境区位的论述进行了评述,并分析和论述了经济全球化和区域经济一体化以及企业组织、企业行为变革和各区域、地方组织等动力机制对边境区位再创造的影响。 相似文献
3.
正电子断层扫描仪与PET图像重建概述 总被引:2,自引:0,他引:2
概述了PET(Positron emission tomography,正电子断层扫描仪)及其图像重建的基本原理、方法与临床使用,介绍了常用的图像重建FBP(滤波反投影,Filtered Back-Projection)算法和OSEM(有序子集最大似然法,Ordered Subset Expectation Maximization)算法,描述了如何通过PET的临床协议中的参数选择以得到满意的重建效果。此外,对PET的准三维重建也做了一些简介。 相似文献
4.
本文研究适用于ICF实验的CT技术,并已用于“星光Ⅱ”装置的激光等离子体的实验X光测量,重建出X光的三维分布,获得了有意义的结果,表明该技术在ICF实验中的应用的可能性。 相似文献
5.
Formation of arcs and backarc basins inferred from the tectonic evolution of Southeast Asia since the Late Cretaceous 总被引:6,自引:0,他引:6
Results of the geological and geophysical surveys in the Daito ridges and basin in the northern West Philippine Basin suggest that the Daito Ridge was an arc facing toward the south from the Late Cretaceous to the Early Tertiary. The Late Cretaceous and Tertiary history of Southeast Asia is evaluated based on these data in the Daito ridges and basins and reconstructed based on overall plate kinematics that have operated in this area. During the Late Cretaceous, the Daito Ridge and the East Philippine Islands were positioned along the boundary between the Indian and Pacific Plates. The western half of the Philippines setting on the Indian Plate approached from the south and collided with the East Philippine–Daito Arc either during the latest Paleocene or the earliest Eocene. It is inferred that the bulk of the Philippine archipelago rotated clockwise and Borneo spun counterclockwise during the Tertiary.From the reconstruction, the formation of backarc basins and their spreading direction are assessed. As a result, some primary causes and significant characteristics are suggested for the opening of backarc basins in Southeast Asia. First, opening of some backarc basins commenced with or was triggered by collisions. Second, backarc basins opened approximately parallel to oceanic plate motion. Third, the formation of some backarc basins was triggered by the approach of a hot spreading center. Fourth, the spreading mode or direction of backarc basins was greatly affected by the configuration of the surrounding continent and was also rearranged to spread approximately parallel to oceanic plate motion.The formation of backarc basins and their spreading direction can be reasonably explained by plate kinematics. However, the generative force responsible for their formation is possibly within the subduction system, particularly to form horizontal tensional force in backarc side. 相似文献
6.
7.
基于奇异谱分析的南方涛动指数短期气候预测试验 总被引:2,自引:0,他引:2
The Southern Oscillation Index (SOI) time series is analyzed by means of the singular spectrum analysis (SSA) method with 60-month window length. Two major oscillatory pairs are found in the series whose pe riods are quasi-four and quasi-two years respectively. The auto-regressive model, which is developed on the basis of the Maximum Entropy Spectrum Analy sis, is fitted to each of the 9 leading components including the oscillatory pairs. The prediction of SOI with the 36-month lead is obtained from the reconstruction of these extrapolated series. Correlation coefficient between predicted series and 5 months running mean of observed series is up to 0.8. The model can successfully predict the peak and duration of the strong ENSO event from 1997 to 1998. It's also shown that the proper choice of reconstructed components is the key to improve the model prediction. 相似文献
8.
图像重建算法FBP与OSEM在工业CT应用中的对比研究 总被引:1,自引:0,他引:1
滤波反投影法(FBP)与有序子集最大期望值法(OSEM)是图像重建中最为常用的两种方法,本文研究了这两种重建方法在工业CT中的应用,就不同的探测器数目、不同的旋转投影角度取样数、不同的噪声水平,对两种方法的重建效果进行对比与分析,结果表明在某些条件下迭代法OSEM重建图像质量明显好于解析法FBP。 相似文献
9.
2004-03-18 23:10~23:50 UT期间,“双星(Double Star)”探测一号卫星(TC 1)在向阳面磁层顶高纬晨侧由内向外穿越磁层顶,其时TC_1的GSM坐标为 (75RE, -55RE, -54RE), RE为地球半径.穿越过程中TC_1观测到了8个通量管和1个磁通量传输事件(FTEs).在此期间Cluster星簇位于向阳面太阳风内,其GSM坐标为(180RE, -31RE, -62RE),其4颗卫星监测到行星际磁场(IMF)的BZ分量持续南向,BY有较大的负值.本文的研究表明:TC_1观测到的前7个通量管具有准周期重现性,周期大约是1~4 min,明显小于以前所观测到的FTEs的平均周期(8~11 min);所有的通量管都具有较强的核心场.本文分别使用最小方差分析法(MVA)和Grad_Shafranov反演方法(GSR)对通量管的轴向进行了分析和对比,发现所有的通量管主轴基本沿晨昏向,结果显示GSR方法在轴向分析上比MVA优越.本文使用GSR方法对通量管的磁场结构进行了分析,恢复出了通量管的磁场在卫星穿越面的结构图;此外,本文还对这次多重通量管事件进行了deHoffmann Teller(HT)分析,结果表明,所有通量管大致朝南极方向运动,均来源于向日面低纬区域.这说明它们可能起源于向日面低纬区,由该区的磁场分量重联产生. 相似文献
10.
本文简介了康普顿背散射扫描仪(CBS)的基本原理,优点,阐述了便携式CBS的特点和对CBS多道分析器的要求,介绍了一种多道分析器的指标,电路原理,工作过程和稳峰技术。 相似文献