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701.
资源型经济转型是我国经济高质量发展及区域协调发展的重要掣肘和关键突破口,同时先进制造业集群已成为提升全球竞争力和创新能力的区域根基。本文主要结合德国德累斯顿区域和美国阿克伦城市群从锈带到世界级先进制造业集群的发展历程,剖析其资源型经济转型及集群化高质量发展的共性路径特征,总结其经验启示。研究发现,区域发展过程是路径创造与演化的过程,德累斯顿区域和阿克伦城市群均持续专注于一到两项界限分明的科技创新建立区域转型发展的磁极,本地蜂鸣与全球网络以及二者之间的互动是转型发展的主导力量;采用以主体多元化、领域跨界化、结构扁平化、组织开放化为主要特征的网络化创新组织模式,有效推动形成了政产学研用协同创新共同体和创新型产业集群;空间组织形态兼顾本区域的地理空间集聚和跨区域的集群间协作;集群组织等网络化协作组织在促进本地技术创新网络、跨区域协同合作网络以及本地-全球互动网络构建和发展中发挥着非常重要的“织网人”作用。建议我国资源型经济区域全面对接国家创新驱动发展战略及集群策动战略,专注于一到两项界限分明的科技创新,以本地根植性为聚集核,以培育发展创新型产业集群为导向,制定区域经济转型与集群化高质量发展的完整路径,同时加快建立集群组织、联盟组织等网络化协作组织,通过其“织网人”和“粘合剂”作用推动构建本地技术创新网络和全球协同创新网络,推进区域发展路径的演化与转型。 相似文献
702.
Chinese Contribution to CMIP5:An Overview of Five Chinese Models’Performances 总被引:4,自引:0,他引:4 下载免费PDF全文
ZHOU Tianjun CHEN Xiaolong DONG Lu WU Bo MAN Wenmin ZHANG Lixi LIN Renping YAO Junchen SONG Fengfei ZHAO Chongbo 《Acta Meteorologica Sinica》2014,28(4):481-509
An overview of Chinese contribution to Coupled Model Intercomparison Project-Phase 5 (CMIP5) is presented. The performances of five Chinese Climate/Earth System Models that participated in the CMIP5 pro ject are assessed in the context of climate mean states, seasonal cycle, intraseasonal oscillation, interan-nual variability, interdecadal variability, global monsoon, Asian-Australian monsoon, 20th-century historical climate simulation, climate change pro jection, and climate sensitivity. Both the strengths and weaknesses of the models are evaluated. The models generally show reasonable performances in simulating sea surface tem-perature (SST) mean state, seasonal cycle, spatial patterns of Madden-Julian oscillation (MJO) amplitude and tropical cyclone Genesis Potential Index (GPI), global monsoon precipitation pattern, El Ni-no-Southern Oscillation (ENSO), and Pacific Decadal Oscillation (PDO) related SST anomalies. However, the perfor-mances of the models in simulating the time periods, amplitude, and phase locking of ENSO, PDO time periods, GPI magnitude, MJO propagation, magnitude of SST seasonal cycle, northwestern Pacific mon-soon and North American monsoon domains, as well as the skill of large-scale Asian monsoon precipitation need to be improved. The model performances in simulating the time evolution and spatial pattern of the 20th-century global warming and the future change under representative concentration pathways pro jection are compared to the multimodel ensemble of CMIP5 models. The model discrepancies in terms of climate sensitivity are also discussed. 相似文献
703.
QUASI-RESONANCE OF BAROCLINIC ATMOSPHERIC WAVES AND EXTRATROPICAL LOW-FREQUENCY OSCILLATION* 下载免费PDF全文
Lu Weisong 《Acta Meteorologica Sinica》1993,7(4):442-453
In operating the quasi-geostrophic two-layer model,the quasi-resonance occurs possibly in two cases:(1)pure barotropic waves;(2) two baroclinic and one barotropic waves.For case (2),we find the analytical solution of triad amplitude of quasi-resonance and approximate expression for the period of wave energy variation.Both the approximate expression and numerical calculation indicate that this period tends to approach the period (2πε)/(△ω) of the quasi-resonance frequency mismatch △ω itself for the baroclinic atmosphere than for the barotropic atmosphere.Physically,there is a feedback mechanism between the wave phase and amplitude,and the slowly varying phase difference between the barotropic wave and the baroclinic wave causes the conversion of kinetic energy and available potential energy,which gives rise to the wave-related low-frequency oscillation alternatively strengthening and weakening with the oscillation period identical to the above approximate formula.For △ω~(0.1-0.02) 0(ωj),the averaged energy period is 12-43 days and when △ω=0,it is 366 days.Therefore,the occurrence of frequency mismatch △ω is probably a new important mechanism for the formation of extratropical low-frequency oscillation in baroclinic atmosphere as well. 相似文献
704.
Jianhui Wei Ningpeng Dong Benjamin Fersch Joël Arnault Sven Wagner Patrick Laux Zhenyu Zhang Qianya Yang Chuanguo Yang Shasha Shang Lu Gao Zhongbo Yu Harald Kunstmann 《水文研究》2021,35(8):e14341
The regional terrestrial water cycle is strongly altered by human activities. Among them, reservoir regulation is a way to spatially and temporally allocate water resources in a basin for multi-purposes. However, it is still not sufficiently understood how reservoir regulation modifies the regional terrestrial- and subsequently, the atmospheric water cycle. To address this question, the representation of reservoir regulation into the terrestrial component of fully coupled regional Earth system models is required. In this study, an existing process-based reservoir network module is implemented into NOAH-HMS, that is, the terrestrial component of an atmospheric–hydrologic modelling system, namely, the WRF-HMS. It allows to quantitatively differentiate role of reservoir regulation and of groundwater feedback in a simulated ground-soil-vegetation continuum. Our study focuses on the Poyang Lake basin, where the largest freshwater lake of China and reservoirs of different sizes are located. As compared to streamflow observations, the newly extended NOAH-HMS slightly improves the streamflow and streamflow duration curves simulation for the Poyang Lake basin for the period 1979–1986. The inclusion of reservoir regulation leads to major changes in the simulated groundwater recharges and evaporation from reservoirs at local scale, but has minor effects on the simulated soil moisture and surface runoff at basin scale. The performed groundwater feedback sensitivity analysis shows that the strength of the groundwater feedback is not altered by the consideration of reservoir regulation. Furthermore, both reservoir regulation and groundwater feedback modify the partitioning of the simulated evapotranspiration, thus affecting the atmospheric water cycle in the Poyang Lake region. This finding motivates future research with our extended fully coupled atmospheric–hydrologic modelling system by the community. 相似文献
705.
706.
警用视频监控的犯罪防控效果及空间差异 ——以苏州市姑苏区为例 总被引:1,自引:2,他引:1
采用双重差分法,对苏州市姑苏区2014~2016年的警情数据进行分析,评估警用治安视频监控的犯罪防控效果。结果表明,视频监控对犯罪具有明显的抑制性作用。在案件类型上,视频监控对盗窃类案件的防控效果较好,但对盗窃电动自行车、盗窃电动车电瓶的防控效果较小。在时间维度上,与节假日相比,对工作日犯罪的抑制效果更好;与晚上相比,对白天犯罪的抑制效果更好。针对通过局部空间自相关分析所获取的重点区域,与警务人员访谈和实地调研后发现,视频监控的犯罪防控效果与周边地理环境、人流密集程度、警务情况等密切相关。 相似文献
707.
Slope instability arisen along with dam construction is a common problem of great concern in reservoir areas. Thus, displacement monitoring of active slopes is of great importance for the safety of dam operation. The unstable Guobu slope is located only about 1.5 km away from Laxiwa hydropower station in upstream Yellow River. In this study, Synthetic Aperture Radar (SAR) datasets acquired by C-band Environmental Satellite (ENVISAT) Advanced Synthetic Aperture Radar (ASAR), L-band Advanced Land Observing Satellite 2 (ALOS-2) Phased Array type L-band Synthetic Aperture Radar 2 (PALSAR-2), and X-band TerraSAR-X covering different evolution stages of Guobu slope were collected to investigate the displacement history so as to facilitate understanding of its deformation and failure mechanisms. The displacements occurred during the past decade were quantitatively identified for the first time by SAR pixel offset tracking analyses. The results show that before the reservoir impoundment, the maximum accumulative displacements on the slope were more than 7 m from 2003 to 2008, while the post-impoundment displacements also exceeded 7 m in just 1 year from September 2009 to September 2010. Furthermore, this slope is still in active deformation up to now. Nevertheless, the displacement rates seem decreased recently according to the interferometric results of TerraSAR-X data pairs from September 2015 to March 2016. 相似文献
708.
709.
采用基于小波分析提取信号趋势项的方法,对实测三浮陀螺漂移数据的趋势项加以提取,并对其残差进行建模。在建立了时序模型的基础上进行卡尔曼滤波器设计,对三浮陀螺的随机漂移数据进行卡尔曼滤波,结果表明,滤波方法有效地抑制了陀螺的随机误差。 相似文献
710.
DGSC—203型液动射流冲击器在地热井的试验 总被引:4,自引:0,他引:4
介绍了新研制的DGSC-203石油钻井液动射液冲击器的性能参数及结构设计上的创新点,测试所获得的排量与压降之间的关系曲线可指导冲击器的使用。生产性试验证明该冲击器工作稳定,可大幅度提高硬地层钻井效率,克服钻柱振动,延长钻柱的使用寿命,具有良好应用前景。 相似文献