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41.
化学物相分析在物料成分全分析数据处理中的应用   总被引:1,自引:0,他引:1  
黄宝贵 《岩矿测试》2009,28(5):439-443
讨论了化学物相分析在物料成分全分析数据加合平衡计算中的作用。根据对不同类型、不同共生组合且具有代表性的物料成分全分析数据平衡计算过程中所推荐的计算程序和计算结果,介绍了化学物相分析在物料成分全分析数据处理中的实际应用。同时阐述了具体应用对象、应用规则、应用模式以及应用过程中需要注意的问题等。  相似文献   
42.
A three-dimensional numerical method was used to simulate cavity expansion during installation and an in situ load test conducted on a single rammed aggregate pier (RAP). Verification of the numerical model was carried out by comparing the computed settlements at top and tip of the pier with the measured values. An un-rammed aggregate pier (UAP) of the same diameter and length was also simulated using the numerical method to demonstrate the effect of installation. Interpretations of the numerical results were focused on the load–settlement behavior, the bulging of the pier, the axial load distributions along the pier, and the stress paths of the soil around the pier. A parametric study was conducted to investigate the influence of the pier length/diameter ratio and the soil properties on the behavior of rammed and un-rammed aggregate piers.  相似文献   
43.
集群与负载均衡是大型在线网站解决网络瓶颈、提高网络灵活性和可靠性的一种策略。文章分析了集群与负载均衡的相关技术,结合陕西省电子地图网站提出了基于集群的地图网站负载均衡策略,并进行了试验。  相似文献   
44.
岩石蠕变破裂过程及其响应比变化的实验研究   总被引:1,自引:0,他引:1       下载免费PDF全文
施行觉  赵闯  李成波  温丹 《地震学报》2010,32(3):332-339
对花岗岩样品进行逐次加载的蠕变实验,得到了加载过程中的蠕变曲线和蠕变破裂的全过程曲线.对加载过程中的杨氏模量、蠕变量、蠕变速率等参数用加卸载响应比方法进行了分析,认为有二种不同形态的响应曲线.在中低应力的弹性阶段其响应比都近似为1,而在高应力的膨胀阶段其响应比都随应力而增加.对应力不变时的蠕变破裂全过程曲线进行了分解,在蠕变破裂过程中,瞬态、稳态和加速3个阶段的持续时间分别为全部时间的18%,75%和7%;在加速蠕变阶段蠕变速率及其响应比明显增加.这一结果是预测蠕变破裂的明显指标.  相似文献   
45.
This paper identifies imbalanced columns (or rows) as a significant source of ill‐conditioning in the preconditioned coefficient matrix using the standard Jacobi preconditioner, for finite element solution of Biot's consolidation equations. A simple and heuristic preconditioner is proposed to reduce this source of ill‐conditioning. The proposed preconditioner modifies the standard Jacobi preconditioner by scaling the excess pore pressure degree‐of‐freedoms in the standard Jacobi preconditioner with appropriate factors. The performance of such preconditioner is examined using the symmetric quasi‐minimal residual method. To alleviate storage requirements, element‐by‐element iterative strategies are implemented. Numerical experiment results show that the proposed preconditioner reduces both the number of iteration and CPU execution time significantly as compared with the standard Jacobi preconditioner. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   
46.
New Zealand's Quota Management System (QMS) consists of a two tier operational structure: Quota shares in a fishstock provide an Annual Catch Entitlement (ACE) of the total allowable commercial catch (TACC) of the specific fishstock. Fishers operating in a multispecies fishery need a portfolio of ACE that matches the mix of their annual catch. Fishers may own quota shares, and thereby receive the needed ACE allocations or they may operate without quota shares and rely on acquiring ACE in the ACE market. Whatever the fisher's situation, it is common for fishers to both buy and sell ACE during a fishing year as they seek to balance their actual catch against ACE. The incentive to achieve a balance is strong because at year-end fishers whose catch exceeds ACE are required to pay a fee called ‘deemed value’. For many fishstocks the deemed value fee increases sharply as the percentage by which a fisher's catch exceeds their ACE increases. When no ‘unbalanced’ ACE is available for purchase, an overfished fisher may attempt to mitigate their deemed value liability by engaging in arbitrage trading in ACE whereby they buy ACE from other overfished fishers. This study examines the nature and extent of ACE arbitrage behaviour in the New Zealand quota managed fishery. The study finds that the number of fishstocks where arbitrage trading occurs is relatively small and is declining. However, sizeable deemed value mitigation transactions are still evident.  相似文献   
47.
李军  李光  邸永强  陈百江 《气象科技》2017,45(2):281-284
目前陕西省气象宽带通信网省、市、县3级连接中,区县局出口是以单台路由器连接双运营商线路接入市局,这一架构造成明显的路由器单点故障风险,同时也不能有效解决台站各业务之间带宽竞争的问题。据此改造市-县级网络拓扑,在区县局出口部署双路由器,分别对接电信、广电运营商线路。启用VRRP(虚拟路由冗余协议),并配置VRRP的负载分担模式,对台站业务根据带宽消耗和时效性高低进行分流传输,在链路冗余的基础上实现了双机热备和负载均衡。同时配置BFD(双向转发检测协议)和VRRP联动,通过BFD监控VRRP路由器的上行链路状态,实现主备路由器的快速切换。经过在西安市多个区县局的广域网建设实践和一年多的业务运行,收到了预期的效果,方案可为同级气象部门提供参考。  相似文献   
48.
通过对顺义地震的序列特征、地震活动与加卸载响应比等前兆异常的时空演化等方面的研究,认为顺义的地震为一次非前光性震群;震前存在地震条带、3级以上地震东移、南北向小震条带、响应经异常地震活动异常以及以顺义板桥水位为主要的破年变等前光异常,这些前光异常的时空演化过程表现出与中强地震类似的具有一定力学基础的三阶段特征,这些结果对北京及邻区的中等以上地震的预测研究与短临跟踪工作都具有重要参考作用。  相似文献   
49.
Implementing acoustic emission experiments with large rock samples, LURR (Load/Unload Response Ratio) theory was studied. The loading conditions in the experiments were designed to simulate the complicated loading process of underground rocks. The damages emerging inside the rock samples were recorded by the acoustic emission technique during the loading process. The experimental results were consistent with prediction by LURR theory. Integrating the changing processes of LURR value Y and the location process of acoustic emission events showed agreement between the variation of LURR value Y and the damage evolution inside the rocks. Furthermore, the high value of Y emerged before the complete breakdown of materials. Therefore, the damage evolution of rock specimen can be quantitatively analyzed with LURR theory, thus the failure of the rock materials and the earthquake occurrence may be predicted. The experimental results gave a further verification of LURR theory.  相似文献   
50.
Web Server集群技术   总被引:1,自引:0,他引:1  
以LVS为例构建了一个集群系统,对部分LVS核心程序进行了修改,并加入了一种新的分配算法,在试验中取得了较好的效果。  相似文献   
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