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在长大公路隧道施工中,进行地质超前预报是非常重要和必要的。超前地质预报工作的成功与否,关系到隧道能否成功修建。文章结合某高速公路长大隧道的工程实际,通过地质雷达方法在超前地质预报中的成功案例,证明了地质雷达在短距离超前地质预报中的重要作用,提出了提高地质雷达波形解释、识别的准确性和精度需要注意的问题,并对最佳作业时间进行了建议。 相似文献
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隧道超前地质预报综述 总被引:2,自引:0,他引:2
在长大公路隧道施工中进行超前地质预报,是减少施工地质灾害、顺利进行施工的关键。文章通过对超前地质预报的方法和步骤进行分析,宏观地对超前地质预报的工作方法和实施步骤进行了探讨,为隧道超前地质预报提供参考。 相似文献
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本文通过对蚕豆田2号隧道右幅涌突水情况和发展过程分析,结合涌突水处岩性分析和水体分析,让我们对不良地质地段隧道施工有了新的体会和认识,隧道不良地质危害不是不可防、不可控,做好超前地质预报,采用合理的技术手段等,危害是可以控制在一定范围内,实践证明该方案制定较为妥当,施工方法是可行的,为类似隧道工程施工中遭遇不良地质地段,出现大量涌水,大塌腔等综合处理提供参考。 相似文献
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隧道水文和工程地质条件复杂多变,难以在地面勘察阶段探明影响隧道施工的不良地质体的具体位置、性质和规模。为保障隧道施工安全,对隧道掌子面前方岩体的地质情况和含水情况进行超前预报,具有重大理论意义和工程价值。本文结合实例,对TSP203成果进行对比分析,总结出隧道含水地层的判别规律,对类似地质条件的隧道超前预报工作具有一定指导意义。 相似文献
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超前地质预报作为隧道工程施工过程中规避施工风险的一项重要保证手段,已被广泛运用。结合石桥头隧道的超前地质预报工作实施情况,分析了地质预报在石桥头隧道中的应用成果,起到了完善设计,优化施工方法的作用,为隧道的安全施工提供了有力的信息支持。 相似文献
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地质雷达法是隧道超前地质预报的常用方法,能有效的探明隧道前方的地质情况,正确指导隧道施工,本文结合具体的工程案列,对探地雷达在公路隧道施工应用进行了分析研究. 相似文献
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随着我国高等级公路建设的迅猛发展,用作路基填筑的材料越来越多,红砂岩就是其中一种较为理想的材料,红砂岩作为路基填料有强度高、稳定性好等诸多优点。本文对红砂岩填筑路基的施工工艺和质量检测控制进行了初步的探讨。 相似文献
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基于logistic-svm组合预测模型在公司信用评级中的应用 总被引:1,自引:0,他引:1
对公司建立信用评价模型,以便及早发现信用危机信号,不仅有利于公司的经营管理,也有利于投资人的投资决策。采用logistic回归模型和支持向量机相结合的组合评价方法,试图寻找出降低公司信用风险的有效措施。试验结果表明,这两种方法的组合预测模型不仅有较高的预测精度,同时也有较好的稳定性,logistic-svm组合模型优于单一模型。 相似文献
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对公司建立信用评价模型,以便及早发现信用危机信号,不仅有利于公司的经营管理,也有利于投资人的投资决策。采用logistic回归模型和BP神经网络相结合的变权组合评价方法,试图寻找出降低公司信用风险的有效措施。试验结果表明,变权组合预测模型不仅有较高的预测精度,同时也有较好的稳定性,变权组合模型优于单一模型。 相似文献
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好的财务管理,能让企业以最小的成本博得最大的利润。作为财务人员,要使企业财务管理实现最佳,要对各方信息了如指掌,对成本支出科学运筹,对风险有科学预测与控制手段,为企业长远发展做好参谋助手。 相似文献
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Attribute Selection is an important issue for developing a prediction model, however, how to determine an effective attribute selection algorithm is an important but difficult issue. Attribute selection can effectively delete the irrelevant and redundant attributes to increase the prediction accuracy, and evaluating attribute selection methods usually need to consider several criteria such as accuracy, type I error, and type II error. In this paper, the selected attribute process is modeled as a group multiple attributes decision making (GMADM) problem. In evaluating different GMACD methods, the most results usually are consistently, But there are some situations where the evaluated outcomes have different results. The GMADM method is useful tool for evaluating attribute selection algorithms, and the TOPSIS is capable of identifying a compromised solution when different GMADM method result in conflicting rankings. Therefore, this paper proposes an objective (persuasive) GMADM-based attributes selection method to solve this disagreement and help decision makers pick the most suitable method. After verification, the proposed model is more persuasive to evaluate the attributes selection methods for developing prediction model. 相似文献
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Although there are encouraging trends, alcohol abuse continues to be a significant public health problem. Econometric studies of alcohol demand have yielded a great deal of information for alcohol abuse prevention policy. These studies suggest that higher alcohol taxes and stricter drunk‐driving policies can reduce heavy drinking and drunk driving. In this paper we explore the role physician advice plays in the campaign to prevent alcohol‐related problems. Compared to alcohol taxation, physician advice is a more precisely targeted intervention that does not impose extra costs on responsible drinkers. Compared to the resource costs of arresting, processing, and punishing drunk drivers, physician advice may be a lower‐cost intervention. To provide a basis for alcohol policy analysis, we use an alcohol demand framework to test whether physician‐provided information about the adverse consequences of alcohol abuse shifts demand to more moderate levels. There are three aspects of our alcohol demand model that complicate the estimation: (1) the dependent variable is non‐negative (it is a count variable—number of drinks consumed); (2) a non‐trivial number of sample observations have zero values for the dependent variable; and (3) because the data we use is non‐experimental, the treatment variable indicating receipt of advice from a physician may be endogenous. We implement an estimation method that is specifically designed to deal with these three complicating factors. Our results show that advice has a substantial and significant impact on alcohol consumption by males with hypertension, and that failing to account for the endogeneity of advice masks this result. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献