Comparison between FLO-2D and Debris-2D on the Application of Assessment of Granular Debris Flow Hazards with Case Study

Numerical simulation has been widely applied to the assessment of debris flow hazards. In East Asia and especially Taiwan, the most widely used numerical programs are FLO-2D and Debris-aD. Although these two programs are applied to the same engineering tasks, they are different in many aspects. These two programs were compared according to their fundamental theories, input and output data, computational algorithms and results. Using both programs, the simulations of a real debris flow with abundant granular material induced by landslides at Xinfa village in southern Taiwan are performed for comparison. The simulation results show that Debris- 2D gives better assessment in hazard area delineating and flow depth predicting. Therefore, Debris-2D is better for simulation of granular debris flows.

Environmental life cycle assessment of Indian coal-fired power plants

Coal is the backbone of the Indian power sector. The coal-fired power plants remain the largest emitters of carbon dioxide, sulfur dioxide and substantial amounts of nitrogen oxides, which are associated with climate and health impacts. Various CO2 mitigation technologies （carbon capture and storage--CCS） and SO2/NOx mitigation technologies （flue gas desulfurization and selective catalytic reduction） have been employed to reduce the environmental impacts of the coal-fired power plants. Therefore, it is imperative to understand the feasibility of various mitigation technologies employed. This paper attempts to perform environmental life cycle assessment （LCA） of Indian coal-fired power plant with and without CO2, SO2 and NOx mitigation controls. The study develops new normalization factors for India in various damage categories, using the Indian emissions and energy consumption data, coupled with the emissions and particulate emission to come up with a final environmental impact of coal-fired electricity. The results show a large degree of dependence on the perspective of assessment used. The impact of sensitivities of individual substances and the effect of plant efficiency on the final LCA results is also studied.

Risk Assessment M ode of Sale-Leaseback——Based on Fuzzy Analytic Hierarchy Process

Sale-leaseback is paid special focus on for its great application in China in recent years.By giving a detailed analysis,an analysis of the features of sale-leaseback and a study of the risks of it are given in this paper.Then a quantitative analysis of commercial real estate sale-leaseback is carried out.The scientific theoretical analysis is provided in this paper for risk assessment in commercial real estate sale-leaseback mode in China.An effective approach is put forward for sale-leaseback project evaluation and prevention of risk.A useful means is given to supervise commerciai real estate sale-leaseback mode for relevant departments and a certain contribution is made to a further sound development of commercial real estate sale-leaseback mode.

Assessing the Impacts of Land Use and Land Cover Changes on Hydrology of the Mbarali River Sub-Catchment. The Case of Upper Great Ruaha Sub-Basin, Tanzania

Intensification of agricultural land use and population growth from 1990-2017 has caused changes in land cover and land use of the Mbarali River sub-catchment which is located in the Upper Great Ruaha Sub basin, Tanzania. This has affected the magnitude of the surface runoff, total water yield and the groundwater flow. This study assesses the impacts of the land cover and land use changes on the stream flows and hydrological water balance components (surface runoff, water yield, percolation and actual evapotranspiration). The land use and land cover (LULC) maps for three window period snapshots, 1990, 2006 and 2017 were created from Landsat TM and OLI_TIRS with the help of QGIS version 2.6. Supervised classification was used to generate LULC maps using the Maximum Likelihood Algorithm and Kappa statistics for assessment of accuracy. SWAT was set up and run to simulate stream flows and hydrological water balance components. The assessment of the impacts of land use and land cover changes on stream flows and hydrological water balance component was performed by comparing hydrological parameters simulated by SWAT using land use scenarios of 2006 and 2017 against the baseline land use scenario of 1990. Accuracy of LULC classification was good with Kappa statistics ranging between 0.9 and 0.99. There was a drastic increase in areal coverage of cultivated land, for periods 1990-2006 (5.84%) and 2006-2017 (12.05%) compared to other LULC. During 2006 and 2017 surface runoff increased by 4% and 9% respectively;however, water yield increased by only 0.5% compared to 1990 baseline period. This was attributed to increased proportion of cultivated land in the sub-catchment which has a high curve number (59.60) that indicates a higher runoff response and low infiltration rate.

Heath Assessment Method of EMU Trains in Level 3-5 Maintenance and Repair

An accurate and objective assessment of the health status of EMU trains is of great importance.In order to make sure the trains are functional,reliable,and endurable in their full life cycle(FLC),health assessment method for EMU trains after Level 3-5 maintenance and repair is studied.First,the element-selection principles and the assessment rules are defined;second,to present the complex topological relationship between the elements in assessment,a functional logical structure construction method is proposed;third,a health value calculation model is defined based on the element’s characteristics and their logical structures.The health variables of each element is calculated and fitted following the steps in the corresponding weight calculation methods.The assessment method is proved to be applicable and effective.

Distribution,fractionation,and contamination assessment of heavy metals in offshore surface sediments from western Xiamen Bay,China

Surface sediment samples were collected at 21 offshore sites in western Xiamen Bay, Southeast China. Total concentrations of Li, V, Cr, Co, Ni, Cu, Zn, St, Mn, Pb, Ba, Fe, and Ti were determined by inductively coupled plasma-optical emission spectrometry; Hg was determined by atomic fluorescence spectrometry. A modified BCR sequential extraction procedure was used to extract fractions of the above elements. Concentrations of Pb, Cr, and Hg at most sites met the primary standard criteria of Marine Sediment Quality except site S12 for Pb and S7 for Cr, while concentrations of Zn at 17 sites and Cu at seven sites exceeded the criteria. The mean concentration of Hg was three times higher than the background, with a possible source being the Jiulong River. Fe, Ti, Ba, Co, V, and Li dominated the residual phase, mainly from terrestrial input. Ni, Cr, Pb, and Hg in the non-residual phase varied largely between sites. Sr, Mn, Cu, and Zn were mainly in the non- residual fraction. Most sites showed considerable ecological risk; exceptions were site S7 （very high） and sites S10, S11, and S14 （moderate）. Cu showed moderate-to-high pollution and Pb exhibited no-to-low pollution, while other metals had a non-pollution status according to their ratios of secondary phase to primary phase （RSP）. Results of two assessment methods showed moderate pollution and a very high ecological risk for Cu, Zn, Ni, and Cr at site S7, which might be due to the local sewage treatment plant.

Assessment of structural damage using natural frequency changes

The present paper develops a new method for damage localization and severity estimation based on the employment of modal strain energy. This method is able to determine the damage locations and estimate their severities, requiring only the information about the changes of a few lower natural frequencies. First, a damage quantification method is formulated and iterative approach is adopted for determining the damage extent. Then a damage localization algorithm is proposed, in which a damage indicator is formulated where unity value corresponds to the true damage scenario. Finally, numerical studies and model tests are conducted to demonstrate the effectiveness of the developed algorithm.

AltBOC navigation signal quality assessment and measurement

In order to ensure that Chinese BeiDou satellite navigation system runs smoothly,the assessment of signal quality has become a significant task.Alternative binary offset carrier(AltBOC)is BeiDou B2 frequency signal.The acquisition of BeiDou signal is processed in off-line mode and the evaluation is performed by taking signal power spectrum,eye diagram,constellation,correlation,loss and s-curve deviation on AltBOC as signal quality evaluation parameters.The results illustrate that the new system signal,namely AltBOC signal,has the best performance in code tracking precision,anti-jamming and anti-multipath.

语言教师测评素养文献综述(2014-2024年)

语言教师测评素养是语言测评领域的研究热点。本文回顾了92篇国内外近10年(2014-2024年)语言教师测评素养相关文献,归纳了语言教师测评素养研究的五大主题:(1)定义与内涵、(2)教师测评观、(3)测评子素养、(4)现状及影响因素、(5)提升路径。本文最后提出未来研究方向,即拓展研究主题,丰富研究方法,扩大研究群体,以期对未来语言教师测评素养研究有所启示。

Enhancing Learners’Performance in Grade 7 Mathematics Through 50-30-20 Exercise

Assessment exercises constitute a crucial component of the teaching and learning process,serving the purpose of gauging the degree to which learning objectives have been accomplished.This study aims to assess the mathematics performance of Grade 7 learners using the 50-30-20 exercise.Specifically,this study seeks to determine the learners’pre-test and post-test mean scores,identify significant differences between the pre-test and post-test results,evaluate learners’exercises,and propose enhanced exercises.The research employs a quasi-experimental design,with 40 Grade 7 learners in the school year 2023-2024 as participants,selected through purposive non-random sampling.Statistical data analysis involves the use of mean,standard deviation,paired t-test,and Cohen’s D effect size.Ethical considerations were paramount,as evidenced by a letter of authorization from the school head outlining the strict adherence to voluntary participation,informed parental consent,anonymity,confidentiality,risk mitigation,results-sharing protocols,and the commitment to keeping research data confidential.The data yielded a remarkable outcome:the experimental group exhibited improvement in both the pre-test and post-test.This result substantiates the initial objective of the study,showcasing a noteworthy and favorable performance among the participants.Consequently,it suggests that a majority of the participants strongly agree that the 50-30-20 exercises contribute to enhancing their understanding and problem-solving skills,as well as their ability to grasp mathematical concepts and improve their overall performance in mathematics.Therefore,the 50-30-20 exercises not only facilitated students in understanding mathematics lessons but were also aligned with the Department of Education’s development plan.

中国大陆东部中-弱活动断层潜在地震最大震级评估的震级-频度关系模型

中国大陆东部中-弱活动断层小区的震级-频度关系符合特征地震模式,其指数函数部分(即G-R关系)的最大截距震级a/b明显偏小于当地的特征震级MC。为了能利用参数a/b间接估计断层小区潜在地震的最大震级,文中发展了综合历史与现代地震资料建立断层小区长期震级-频度关系的方法,计算出130个断层小区按t=500a归算的G-R关系参数at/b值。分析表明,断层小区已发生的最大地震震级Mmax与at/b值呈正相关,且随着at/b值的增大,最大地震震级Mmax的上限呈现较平整、单调上升的特点。已基于这种特点分别建立起华北、华东—华中、华南与东南沿海三大区域的最大地震震级上限Mmu-at/b值关系的3个经验公式,作为利用at/b值估算断层小区潜在地震最大震级的经验模型。文中应用新发展的方法与模型估计了若干断层小区的潜在地震最大震级。研究还揭示出中-小震群、余震和触发型地震序列、人为诱发地震等现代异常地震活动以及最小完整性震级的确定等均对断层小区的at/b值计算有影响。

三种营养筛查工具对维持性血液透析病人透析相关性蛋白质-能量消耗的评价比较

目的:比较三种营养筛查工具对血液透析病人透析相关性蛋白质-能量消耗(PEW)的预测作用,以筛选出一种快速、准确和易行的方法。方法:采用营养风险筛查2002(NRS 2002)、7分主观整体评估(7分SGA)、营养不良炎症评分(MIS)三种筛查工具对205例行维持性血液透析病人进行PEW患病率调查。同时,将三种筛查工具与人体测量指标、血生化指标等进行相关性分析,并与国际肾脏营养与代谢学会(ISRNM)制订的PEW诊断金标准进行比较。结果:根据ISRNM标准,31.2%的透析病人存在PEW,基于MIS、7分SGA、NRS 2002的评价标准,透析病人PEW的患病率分别为58.0%、40.8%和46.8%。三种筛查工具均与血生化和人体测量学指标呈明显相关关系(P<0.05),其中NRS 2002与常用客观营养指标的复合相关系数最大(r=0.787,P<0.001),相关性最为密切。在透析病人中,NRS 2002有较高的灵敏度和正确指数,分别为87.5%和59.1%。结论:对透析病人,MIS、7分SGA、NRS 2002三种筛查工具均有较好的准确性,以NRS 2002更优。NRS 2002可能是预测透析病人PEW更快速、准确、易行的营养筛查工具。

Preliminary Pointing Bias Calibration of ZY3-03 Laser Altimeter

ZiYuan3-03(ZY3-03)satellite was launched on July 25,2020,equipped with China’s second-generation laser altimeter for earth observation.In order to preliminarily evaluate the in-orbit performance of the ZY3-03 laser altimeter,the pointing bias calibration based on terrain matching method was adopted.Three tracks of laser data were employed for the ZY3-03 laser altimeter calibration test.Three groups of pointing parameters were obtained respectively,and the mean value of pointing is considered as the optimal calibration result.After calibration,ZY3-03 laser pointing accuracy is greatly improved by the method,and its pointing accuracy is approximately 12.7 arcsec.The first-track laser data on the Black Sea surface is used to evaluate the relative elevation accuracy of ZY3-03 laser altimeter after pointing bias calibration,which is improved from 0.33 m to 0.19 m after calibration.Meanwhile,the absolute elevation accuracy of ZY3-03 laser altimeter after pointing bias calibration is evaluated by the Ground Control Points(GCPs)measured by RTK(Real-Time Kinematic),which is better than 0.5 m in the flat terrain.

基于特征匹配度与异类子模型融合的安全性评估方法

机器学习模型的好坏影响预测精度、输入与输出结果的拟合情况。在复杂系统中,使用单一模型评估系统安全性问题时容易受数据量、数据格式、模型结构以及环境干扰等因素影响,使得这个模型在解决某个问题的能力上比较出色,而在解决其他问题时,结果却不尽如人意。针对上述问题,提出一种基于特征匹配度和异类子模型融合的安全性评估方法。首先,按照采样数据的输出值划分不同规模的数据集并构建子模型;其次,通过计算每个新数据对于这些子模型的匹配度,进而得到每个子模型的权重;最后,根据权重大小融合所有子模型的子输出得到最终的多模型融合结果。所提方法对山东省济宁市霄云煤矿采掘数据集进行研究,实验结果表明,该方法与多样本单模型、少样本单模型和传统多模型方法相比,在以330/70的比例来构建子模型的情况下均方根误差(RMSE)分别降低了15.13%、51.67%和12.46%,该方法充分集成各子模型所能提供的有效信息,减少和分散单一模型的预测误差,以提高模型的预测精度和泛化能力。

基于频域阻抗的新能源并网振荡风险评估方法

随着新能源装机规模不断增加,如何评估由其引发的系统次/超同步振荡风险是目前电网运行高度关注的重要问题。提出了一种基于频域阻抗的新能源并网振荡风险评估方法,首先利用系统各元件频域导纳模型形成网络节点导纳矩阵,实现对新能源场站并网点系统侧网络等效阻抗的计算,能准确反映电网结构特性以及网内其他设备的动态特性,然后结合新能源场站阻抗特性,通过阻抗分析评估新能源场站并网振荡风险。该方法采用电路节点分析法,算法易于实现,能够适应系统结构和运行方式变化,充分反映网侧动态元件的影响,可利用电网同步相量测量装置提供的结构和潮流数据对系统内新能源场站并网振荡风险进行评估分析。以某地区实际电力系统为研究对象,利用所提方法展开了次同步振荡风险评估,同时基于特征值法和时域仿真验证了评估结果的准确性和评估方法的有效性。

基于ALFF/fALFF的肾虚证认知功能下降的神经机制研究

目的初步探究肾虚证亚健康人群认知功能改变的神经影像学机制。方法对35例肾虚型亚健康受试者和35例健康对照进行重复性成套神经心理状态测验(Repeatable Battery for the Assessment of Neuropsychological Status,RBANS)及评估,并进行静息态功能磁共振扫描。应用皮质分析方法计算两组被试脑区的低频震荡振幅(amplitude of low frequency fluctuations,ALFF)值和分数低频振幅(fractional ALFF,fALFF)值,并分析异常功能活动脑区与认知功能及临床症状之间的相关性。结果与健康受试者相比,肾虚型亚健康受试者的即刻记忆、注意编码及RBANS测验总分显著降低;并发现其左侧初级视觉皮质、左侧背侧枕叶皮质及右侧辅助运动皮质等脑区的ALFF/fALFF值异常改变。此外,左侧背侧枕叶皮质、右侧额叶眼动区ALFF值,左侧初级视觉皮质fALFF值与肾虚证积分均成正比。右侧额叶眼动区ALFF值,右侧辅助运动皮质fALFF值与测验总分成反比。结论肾虚型亚健康受试者的记忆与注意功能受损,左侧枕叶和右侧额叶等多个脑区神经活动的改变可能是肾虚证亚健康人群认知功能改变的潜在神经机制。

湖北省“多测合一”成果质量检查的实践与思考

根据湖北省2023年开展的工程建设项目“多测合一”竣工验收阶段成果质量检查工作,总结了“多测合一”成果质检的技术流程,制定了“多测合一”成果的质量(子)元素、重点检查项、权重表,提出了“多测合一”成果检查项的数学精度评分方法和成果质量评分方法,分析了“多测合一”成果的主要质量问题以及在质检实施中遇到的问题,最后对湖北省未来开展“多测合一”成果质检工作提出了相关建议,经验做法值得借鉴和推广。

园区类项目区域雷击风险评估应用探讨

介绍区域雷击风险评估相关内容,包括项目前期勘测、闪电定位资料应用、评估子区域划定标准和区域雷击风险评估模型;以上海某化工园区为例,介绍项目基本情况、雷电环境特点、子区域划分,给出评价指标隶属度及区域雷击风险值的计算结果;提出在区域雷击风险评估时,应尽可能通过现场勘测、调研问卷等多种形式详细了解项目基本情况,并结合雷电分布特征详细划分子区域,开展区域雷击风险评估。

基于GIS的中国气候分区及综合评价

气候是生态环境的一个重要因子，也是生态环境评价中的重要指标。本文应用地理信息系统技术，基于全国1973年～2002年734个气象站点的基本气象数据，计算了各气象站的多年平均气温、≥10℃积温、干燥度、年降水量和年降水变率等气候指标；对每个气候指标，利用聚类分析，将全国分成4～7个区域，进而在每个分区里利用“回归分析＋残差修正”的方法进行插值，生成各气候指标的1km×1km栅格数据，最后利用层次分析法（AHP）建立全国的气候综合评价模型，对我国气候进行了综合评价，实现了参考土壤、植被等其他空间数据、进行气候要素区域空间变异的定量化表达及综合分析与评价。

城市小区规划对大气环境影响的评估研究

不同城市小区规划方案对大气环境的影响不同。本文在已建城市小区尺度气象和污染扩散模式的基础上,针对城市小区规划对气象及大气环境的影响,提出了一套以人为本的客观、科学、可操作的影响评估指标及方法,并以北京市某小区两种规划方案为例,具体评估了它们对气象及大气环境的不同影响。结果表明:由于第二种规划方案在小区中部有一条较宽的东西向道路,并且道路中绿化较多,这条道路是气流东西向流动的重要通道,道路附近风速较大、气温较低、污染较轻,并且对整个小区的气象和大气环境都有改善。由此可见,基于城市小区尺度模式,对城市小区规划对大气环境的影响进行评估是必要和可行的。本文提出的人体舒适度、行人舒适度、地面污染物浓度、最高建筑高度以下污染物浓度、建筑物表面污染物浓度及扩散能力等六项评估指标,并分别给予该6种指标的权重系数为0.2,0.1,0.1,0.1,0.1及0.4,然后再加权平均的评估方法是合理可行的。