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1.
非开挖技术在市政管道铺设中的应用越来越广泛,从直径50mm通讯光缆-直径3000mm混凝土管道,采用非开挖安装各种管道都变得很普遍。同时,鉴于非开挖技术综合效益优越性、环境友好型施工特点,也逐渐被工程建设方、社会所接受和认可。泥水平衡顶管技术是非开挖最为成熟的技术之一,在城市市政设施建设中也起着举足轻重的作用。采用泥水平衡顶管技术进行城市雨污分流改造已经在国内大量城市取得应用,但是,采用泥水平衡顶管在岩层中铺设直径达2000mm埋深在5m电力管道,在国内为数不多,在福建厦门地区也是尚属首次。通过在工程施工中对设备、施工工艺的摸索和改进,最后采用泥水平衡顶管施工技术成功铺设建设方所要求的电力管道。本工程将为在福建地区采用预管技术铺设大口径长距离、曲线管道提供了指导和借鉴。  相似文献   
2.
阐述 PBS 型地震仪 CF 卡的工作原理、硬件电路接口设计及底层驱动设计,并按照 FAT32文件系统格式,实现文件存储,可方便地震记录文件在 Windows 系统下的识读,为后期数据分析与解释提供便利。  相似文献   
3.
Traditional precipitation skill scores are affected by the well-known“double penalty”problem caused by the slight spatial or temporal mismatches between forecasts and observations. The fuzzy (neighborhood) method has been proposed for deterministic simulations and shown some ability to solve this problem. The increasing resolution of ensemble forecasts of precipitation means that they now have similar problems as deterministic forecasts. We developed an ensemble precipitation verification skill score, i.e., the Spatial Continuous Ranked Probability Score (SCRPS), and used it to extend spatial verification from deterministic into ensemble forecasts. The SCRPS is a spatial technique based on the Continuous Ranked Probability Score (CRPS) and the fuzzy method. A fast binomial random variation generator was used to obtain random indexes based on the climatological mean observed frequency, which were then used in the reference score to calculate the skill score of the SCRPS. The verification results obtained using daily forecast products from the ECMWF ensemble forecasts and quantitative precipitation estimation products from the OPERA datasets during June-August 2018 shows that the spatial score is not affected by the number of ensemble forecast members and that a consistent assessment can be obtained. The score can reflect the performance of ensemble forecasts in modeling precipitation and thus can be widely used.  相似文献   
4.
基于华南地区自动站逐小时观测资料, 采用传统站点评分、邻域法等评估华南区域高分辨率数值模式(包括GRAPES_GZ_R 1 km模式和GRAPES_GZ 3 km模式)对降水、地面温度和风场等要素的预报能力。结果表明: GRAPES_GZ_R 1 km模式的降水预报技巧优于GRAPES_GZ 3 km模式, 模式预报以正偏差为主。对于不同起报时间的预报, 00时(世界时, 下同)起报的预报效果优于12时。GRAPES_GZ_R 1 km模式的TS评分是GRAPES_GZ 3 km模式的两倍以上, 对不同降水阈值的评分均较高。分数技巧评分(FSS)显示GRAPES_GZ_R 1 km模式6 h累计降水预报在0.1 mm、1 mm及5 mm以上的降水均可达到最低预报技巧尺度, 对所检验降水对象的空间位置把握能力更好。2 m气温和10 m风速检验结果表明两个模式均能较好把握广东省温度的分布特征, GRAPES_GZ_R 1 km模式对2 m气温预报结果优于GRAPES_GZ 3 km模式, 预报绝对误差更小; 两个模式对风速的预报整体偏强, 预报偏差在1~4 m/s之间, 但相比之下GRAPES_GZ 3 km模式在风场预报上表现更好。GRAPES_GZ_R 1 km模式的2 m气温和10 m风速预报偏差随降水过程存在明显波动, 强降水过后温度预报整体偏低, 风速预报偏强, 在模式产品订正、使用等需要考虑模式对主要天气系统的预报情况。总的来说, GRAPES_GZ_R 1 km模式的预报产品具有较好的参考价值。   相似文献   
5.
主要介绍了新型波浪采集系统的设计思想与主要参数,采集、存储、运算和电源控制部分的结构与组成,以及各部分的特点和关键技术。  相似文献   
6.
王保君 《城市地质》2012,7(2):27-29
本文在依据郑州北郊地区水文地质条件,分析了其水源地深层地下水的补给量和排泄量:中深层地下水补给量为7152m3/d,排泄量为7134m3/d,均衡差为18m3/d;开采条件下,中深层地下水的补给量为46301m3/d,排泄量为46320m3/d,均衡差为-19m3/d。  相似文献   
7.
Coastal areas are characterised by the choice of performance measures and/or reference points which may be critical in the environmental management process, determining the success of an Integrated Coastal Zone Management (ICZM) plan. The tools for the strategic control of ICZM plans are particularly important, although they are still not widely used at the local level. The following paper proposes the use of the Balanced Scorecard (BSC) method of Kaplan and Norton (1992), which is a holistic management performance tool that can be used by managers to put into action their business strategy. In particular the methodology has focused on the use of a BSC process, inspired by the Niven (2003) approach for public bodies. The BSC suggests the creation of a framework for the strategic assessment of plans and projects based on the Protocol on Integrated Coastal Zone Management in the Mediterranean (Protocol). An analysis of the Protocol has been carried out according to the BSC model, and it shows how it can be integrated with assessment and environmental management tools, such as the Driving forces, Pressures, States, Impacts and Responses (DPSIR) framework. The proposed process has suggested a novel framework for analysing the ICZM plans of coastal managers and stakeholders. The analytical framework facilitates the examination of Drivers and causes of the ICZM strategy, the possible impact on society and coastal communities, the most appropriate measures to achieve the objectives and the practicalities of implementing such measures given the institutional context of where these are developed.  相似文献   
8.
酸溶——催化极谱法测定地质样品中的钨、钼   总被引:3,自引:0,他引:3  
陶秋丽 《陕西地质》2008,26(1):82-86
本文采用混合酸溶解样品,对影响催化体系稳定的酸度、温度和不同反应时间的因素分别进行了对比试验,确定催化体系相对稳定的最佳条件,经过大量样品的分析验证,分析方法可靠。  相似文献   
9.
In the Yangtze Block (South China), a well-developed Mesozoic thrust system extends through the Xuefeng and Wuling mountains in the southeast to the Sichuan basin in the northwest. The system comprises both thin- and thick-skinned thrust units separated by a boundary detachment fault, the Dayin fault. To the northwest, the thin-skinned belt is characterized by either chevron anticlines and box synclines to the northwest or chevron synclines to the southeast. The former structural style displays narrow exposures for the cores of anticlines and wider exposures for the cores of synclines. Thrust detachments occur along Silurian (Fs) and Lower Cambrian (Fc) strata and are dominantly associated with the anticlines. To the southeast, this style of deformation passes gradually into one characterized by chevron synclines with associated principal detachment faults along Silurian (Fs), Cambrian (Fc) and Lower Sinian (Fz) strata. There are, however, numerous secondary back thrusts. Therefore, the thin-skinned belt is like the Valley and Ridge Province of the North American Applachian Mountains. The thick-skinned belt structurally overlies the thin-skinned belt and is characterized by a number of klippen including the Xuefeng and Wuling nappes. It is thus comparable to the Blue Ridge Province of Appalachia.The structural pattern of this thrust system in South China can be explained by a model involving detachment faulting along various stratigraphic layers at different stages of its evolution. The system was developed through a northwest stepwise progression of deformation with the earliest delamination along Lower Sinian strata (Fz). Analyses of balanced geological cross-sections yield about 18.1–21% (total 88 km) shortening for the thin-skinned unit and at least this amount of shortening for the thick-skinned unit. The compressional deformation from southeast to northwest during Late Jurassic to Cretaceous time occurred after the westward progressive collision of the Yangtze Block with the North China Block and suggests that the orogenic event was intracontinental in nature.  相似文献   
10.
最近十年来中国地理科学的进展   总被引:10,自引:0,他引:10  
最近十年来中国地理科学的最重要进展有:自然地理学与人文地理学的平衡发展,人口、资源、环境的研究,遥感的应用与地理信息系统的建立,自然地理定位观测,青藏高原隆起对自然环境的影响,城市与城市规划,中国历史地理研究等。最近,并已开始研究气候变化与海平面上升对中国的影响,使我国地理科学研究紧紧跟上世界发展的步伐。  相似文献   
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