可视化灾害数字仿真重构理论及实证研究--灾害本质解析及仿真理论可行性分析

可视化灾害数字仿真重构理论研究，不仅可以实现对灾害空问数据进行有效的集成管理和时空分析，而且为灾害的防治、应急管理和工程论证等提供可靠的依据，是解决灾害实验的危险性和不可重复性的最佳途径。本文在综述灾害防治手段及相关研究进展的基础上，明确了灾害的定义和特征，论述了灾害的分类与分级方法，研究了孕灾环境、承灾体和致灾因子的成灾模式，提出了灾害空间的涵义。在灾害本质解析的基础上，提出灾害数字仿真重构理论的概念，并论证了理论的可行性，为进一步的研究创造了条件。     

在数字信号处理中二进制数量化引起的有限字长效应

在数字信号处理中,采用不同的二进制数的表示方法及量化方式,其误差相距甚远.本文首先分析二进制数的不同表示方式是产生有限字长误差的直接原因,然后对三种二进制数的表示方法及两种量化方式做了详细的说明及分析,同时,还利用MATLAB对不同量化方式的误差敏感性进行了分析,并针对具体问题进行了归纳和总结,提出了相应的解决方案.信号处理在林业森林生态信息处理以及林业生产安全信息处理等方面具有重要的意义.     

FLEXIBLE PRICING IN WATER SUPPLY PLANNING–FOR FLEXIBLE ENGINEERS1

ABSTRACT. Preliminary results from a digital simulation model designed to test time-varying water pricing policies are presented. Stochastic inflows feeding a water supply reservoir are assumed for a hypothetical community with defined demand functions. Prices are allowed to vary as a function of reservoir level, generally rising as reservoir levels fall. Increasing, decreasing and constant rates are tested. It is concluded that varying the price to reflect the increased value of scarce supplies can greatly reduce the risk of water supply shortages. It is also concluded that varying incremental (conservational) pricing policies not only reduces the risk of shortages, but also lowers the average price to the community while rewarding the low consumption user with lower average rates.     

数字化测图与环境的关系

随着测绘科学技术的发展,数字化测图已替代了原有白纸测图,它既降低了成本又保护了环境。环境保护是一项利国利民的大事,在各个行业都应该重视它从小事做起从点滴做起。本文从数字化测图工作的外业、内业以及测量成果表现形式上,对数字化测图的特点进行了分析;分析了数字化测图质量评价的内容和特点;结合数字化测图的工作实践,对数字化测图工作提出了几点有益的认识。     

无人机数字摄影测量与激光雷达在地形地貌与地表覆盖研究中的应用及比较

无人机数字摄影测量（UAV-DAP）与激光雷达（LiDAR）凭借其机动灵活、高效便捷和高分辨率的特点,在地形地貌、生态监测、工程勘察、环境规划、林业资源清查等领域得到广泛应用。本文针对数字摄影测量与激光雷达的技术特征和应用趋势,着重比较两者在数据采集、数据处理、应用领域以及成本耗费等方面的区别,分析了两种技术在林业资源清查、地形地貌研究、灾害防控等领域的最新应用动态,并且基于两者的技术特点和发展动态提出了进一步的可能应用前景。基于运动结构重建算法的数字摄影测量技术获得的数字地表模型在一定条件下可以达到激光雷达技术的超高空间分辨率程度（如0.2 m×0.2 m）,但是数字摄影无法穿透植被冠层,而激光雷达可以较好地穿透植被层从而获取植被及地表信息。然而数字摄影测量技术设备简单、操作方便,成本低廉,并具有较高的空间分辨率,因而能够和高精度、高耗费、大数据量的激光雷达技术形成优势互补。无人机数字摄影测量与激光雷达技术是林业资源清查、地形地貌研究、灾害防控等领域在快速响应、高精度调查、多时期扫描等方面进一步发展的重要突破口。     

Small enterprises and major hazards: How to develop an appropriate safety management system

Many small and medium sized enterprises (SMEs) are obliged to adopt a Safety Managements System (SMS) by the Directive 2012/18/EU for the control of Major Accident Hazards (Seveso III). The difficulties of implementing an SMS within a small sized work organization are well known by practitioners, including inspectors and auditors and have been discussed in many recent papers. In the present paper is discussed a new method, based on the bowtie model, to build an easy and effective SMS. The very core of this method is a “safety net model”, which is able to connect in a network all the tangible and intangible elements of safety, including equipment, operating instructions, procedures and safety documents. This safety model has been used as the core of a smart application, the strength of which is the workers' contribution. The application allows the users to build step by step an SMS. It starts from a first version based just on regulations and standard codes (version 0), then it integrates internal knowledge through the bowtie paradigm (version 1). Near misses' discussion is used to transfer actual workers' experience into the system, to get intermediate improvement of the SMS (version 1.x). At the end audit may be used to a major release of the SMS (version 2). The full cycle has been tested at two small Seveso establishments: a galvanic plant and small glue manufacturer.     

Interpolating SRTM Elevation Data to Higher Resolution to Improve Hydrologic Analysis

The Shuttle Radar Topography Mission (SRTM) digital elevation model (DEM) has been a valuable resource for hydrological analysis, providing elevation data at a consistent resolution on a near‐global scale. However, its resolution (three arc‐second or 90 m) is sometimes too low to obtain the desired level of accuracy and precision for hydrologic analysis. We evaluated the performance of several methods for interpolating SRTM three arc‐second data to a 30‐m resolution grid to better represent topography and derive terrain characteristics of the landscape. STRM data were interpolated to 30‐m DEMs on a common grid using spline, inverse distance weighting (IDW), kriging (KR), natural neighbor methods, and cubic convolution (CC) resampling. Accuracy of the methods was assessed by comparing interpolated and resampled 30‐m grids with the reference data. Slope, aspect, sinks, and stream networks were derived for the 30‐m grids and compared on a cell‐by‐cell basis to evaluate their performance in reproducing the derivatives. The comparisons identify spline and KR as the most accurate interpolation methods, of which spline is preferred because of its relative simplicity. IDW provided the greatest bias in all methods with artifacts evident in slope and aspect maps. The performance of CC projection directly to a 30‐m resolution was comparable to spline interpolation, thus is recommended as the most convenient method for interpolating SRTM to a higher resolution.     

施工过程安全数字孪生模型的构建和应用*

为解决施工过程安全信息的虚实交互难题,降低施工过程安全风险,提出施工过程安全数字孪生模型。建立施工过程安全语义本体,分析施工过程安全关键知识要素;定义施工过程安全数字孪生五维模型,明确模型的构成和功能,基于物联网和有限状态机构建施工过程安全监控方法,并以塔吊顶升活动安全监控为例进行应用。研究结果表明:该模型能够实现塔吊顶升施工过程安全的数字化表达、参数化监测和自动化控制。     

数字经济何以推动乡村生态振兴？——基于中国省级面板数据的经验证据

数字经济具有生态化的本质，是提高乡村生态演进韧性、全面推进乡村振兴的关键动力。在系统梳理数字经济对乡村生态振兴影响的直接机制、中介机制基础上，本文利用2010—2020年省级面板数据，运用固定效应模型、中介效应模型等方法，多维度实证考察了数字经济对乡村生态振兴的影响机制。研究结果表明：数字经济发展显著推动了乡村生态振兴，在运用分时间段检验、剔除特殊值方法进行稳健性检验后，该结论仍然成立。数字经济发展对乡村“三生”环境的影响大小有所差异，对乡村生活绿色宜居化的影响最大，对乡村生产绿色低碳化的影响次之，对乡村生态本底品质化的影响最小。中介效应显示，农村经济增长、绿色科技创新和环境规制都是数字经济助力生态振兴的重要机制。异质性分析表明，数字经济影响乡村生态振兴的效应大小呈现出“西部>中部>东部”态势，总体上，中西部地区数字经济的绿色赋能效应更为显著。因此，应强化农村数字基础设施建设，充分发挥数字经济在农村生态经济增长点培育、企业绿色科技创新及环境监管、宣教引导等方面的作用，因地制宜以差异化的数字化策略提升赋能乡村生态振兴的有效性。     

基于集对分析-吸收马尔可夫链的铁路移动通信系统安全动态评估*

为了更有效地评估和防范铁路数字移动通信系统（GSM-R）的安全风险，针对未考虑系统不同时期系统风险状况不同、研究多局限于静态评估的不足，提出基于马尔可夫链的风险指数量化计算方法，构建基于集对分析-吸收马尔可夫链的铁路数字移动通信系统（GSM-R）风险评估模型。首先使用吸收马尔可夫链对通信系统风险进行定量计算，运用集对分析关联度的同一性、差异性和矛盾性动态分析通信系统安全风险的趋势，通过结合马尔可夫链计算下一阶段的关联度以获得通信系统最终安全风险评估结果，选取通信系统6个时间段数据进行分析，并进行验证。结果表明:本文评估方法能实现铁路数字移动通信系统（GSM-R）安全风险的全面动态评估，验证通信系统安全风险动态评估模型的科学性、有效性和可行性。