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1.
应用遥感与地理信息系统技术构建基于GIS模型的蓄滞洪区空间数据库,对蓄滞洪区内的基础地理数据进行存储、管理,并对空间数据进行可视化和空间分析等操作;运用RS技术对蓄滞洪区内的土地利用、生态环境变化等情况进行动态监测,建立蓄滞洪区发展指标体系;探求蓄滞洪区的和谐发展模式,为蓄滞洪区的可持续发展提供科学依据。  相似文献   
2.
ABSTRACT

Tourists’ hotel event experiences have received little attention in tourism research. By proposing an integrated model of expectation–confirmation theory (ECT) and the experience economy concept, this research explores the relationship between tourists’ event experience and their satisfaction regarding the hotel event setting. The hypothesized model was empirically validated using a sample of 663 tourists who experienced a holiday event at a resort hotel. Results confirmed that the integration of the experience economy and ECT provided a better understanding of tourists’ post-satisfaction in a pleasure-driven setting. This affective–cognitive approach advances the knowledge of tourists’ experiences and satisfaction at hotel events.  相似文献   
3.
This study examines determinants of materiality disclosure quality (MDQ) in integrated reporting (IR) in an international setting. To this purpose, we constructed a novel, hand‐collected MDQ score in line with the <IR> guiding principles introduced by the International Integrated Reporting Council. On the basis of a cross‐national sample consisting of 359 firm‐year observations between 2013 and 2016, we find that MDQ is positively associated with learning effects, gender diversity, and the assurance of nonfinancial information in the integrated report. On the other hand, we find that IR readability, listing in the Dow Jones Sustainability Index, and earnings management do not affect MDQ. Our results are robust to different statistical models. We expand on earlier empirical findings on IR disclosure quality and provide valuable insights for research, practice, and standard setting.  相似文献   
4.
ABSTRACT

This paper examines the annual departmental reports prepared by Maltese government departments and highlights the gap between current practices and integrated reporting (IR). The authors suggest that principles and elements of IR could be gradually introduced in an effort to enhance transparency and accountability. The internalization of integrated thinking could also lead to enhanced value creation, and overcome the silo mentality that characterizes the Maltese public sector. Detailed guidelines for preparing ADRs urgently need to be developed in Malta—preparers should not expect to find them in the IIRC Framework, because they are not there.  相似文献   
5.
针对机载多传感器成像战场态势感知的问题,提出了一种合成孔径雷达(Synthetic Aperture Radar,SAR)与可见光图像压缩感知融合增强方法。该方法首先对SAR与可见光图像分别进行压缩感知测量,得到压缩测量值,然后通过基于局部权值的融合方法实现对压缩测量值的融合,再利用有序度最优分割法提取SAR图像的强散射目标,最后对融合测量值重建得到初步融合图像,初步融合图像通过目标对比度增强得到最终融合图像。对多组图像进行了仿真分析,视觉及数值结果表明该方法能显著增强融合图像的目标对比度,提升了图像纹理清晰度,较大程度降低了图像融合过程中的数据计算量。  相似文献   
6.
[目的]软硬变化区的划分是进行遥感变化检测技术识别农作物的基础。为解决人工判读方法中存在人为主观因素影响以及自动判别和交互式判别方法对不同研究区的适用性问题,该文提出基于剖线梯度变化(Profile based Gradient Change Magnitude,PGCM)进行软硬变化区划分的方法。[方法]该研究选择破碎农业景观种植区域为研究区,计算拔节期Quick Bird影像和播种期模拟影像两个时相的变化强度,从作物地块内部向外绘制剖线,利用剖线强度的梯度变化确定硬变化区(Hard change region,HCR)、软变化区(Soft change region,SCR)和未变化区(Non change region,NCR)3者间的划分阈值。[结果]从识别结果来看,PGCM能够有效在地块边界处探测到软变化像元,进而确定HCR、SCR。像元分辨率在5~60 m不同尺度下,识别HCR区混入比例为11%~16%,混入比例随着分辨率下降而降低;NCR区混入比例为3%~4%,受分辨率尺度影响不大;SCR区识别比例为74%~86%,识别精度较高,识别结果与冬小麦空间分布结果保持一致。[结论]PGCM方法能够自动、便捷地确定阈值,摆脱人工判定的主观性,有效地划分出HCR、SCR和NCR 3个区域,为进一步HCR、SCR区内的作物识别提供基础。  相似文献   
7.
以浙江电网企业转型现代能源综合服务的具体战略与发展规划为研究背景,针对能源综合服务系统的运行规划目标,开展基于运行规划的能源综合服务系统能效管理研究。从系统工程的视角出发,以能源流为纽带,基于多尺度能源系统建模方法,构建了能源综合服务系统模型,并结合系统综合能效,采用粒子群优化算法来优化系统各设备单元的运行策略,以实现基于运行规划的最优能效管理。通过能源综合服务系统模型计算表明,大规模清洁能源和可再生能源的接入,可以明显提高系统综合能效;随着区域用户总冷量和/或总热量需求占总电力需求的比值增大,系统最优综合能效逐渐增大;与使用内燃机、燃气轮机及汽轮机为原动机的热电联产系统相比,使用燃料电池为原动机的热电联产系统可以使能源综合服务系统综合能效更优。  相似文献   
8.
The objective of the conducted research is the identification and determination of requirements of members of fire rescue brigades during operations in the conditions of high risk in order to minimize the possibilities for injury incidence during the intervention. The research is focused on examination, determination and identification of factors affecting the increasing number of occupational injuries of members of fire rescue brigades during interventions. Hypothetical framework of the research problem consists of general hypothesis and six special hypotheses. Results suggest that almost all respondents believe that their skills and abilities are applicable in the intervention phase, but less than a half believe that their skills are applicable in prevention phase. Two-thirds of respondents stated that in their organization they have support for further education and upgrading while a half of respondents stated that they need education concerning identification, assessment and management of risks that can lead to emergency situations.  相似文献   
9.
对于无人机遥感来说,融合了无人机技术与遥感技术。在无人机遥感技术应用的过程中,涵盖了诸多不同类型的先进技术,比如,无人机驾驶飞行技术、通讯技术、遥感传感器技术等,存在着显著的智能化、自动化等不同方面的特征,能够迅速得到相关资源,并且系统掌握国土、环境等不同方面的信息,然后加以实时化处理,通过建模与科学分析,能够制定出无人机遥感技术运用的具体策略,凸显出其良好的功效。本文针对无人机遥感系统的研究进展进行了详细地分析,同时说明了无人机遥感系统的应用前景,进而对有关研究人员形成一定的启发。  相似文献   
10.
Over the last four decades, the loss of agricultural land has been observed in Egypt at high rates. However, the highest rates of losses have occurred since the January 25th revolution in 2011. Greater Cairo (GC), which is the largest metropolitan in Egypt, has witnessed a massive loss of agricultural land since the 2011 revolution. However, until now, no study or official report has revealed the volume of agricultural land losses in this region. This study quantifies agricultural land losses around the GC using Landsat satellite images from 2010 and 2018. Supervised classification was performed using the maximum likelihood algorithm in QGIS software. A post-classification comparison method was applied to detect the land use/land cover changes between the classified images; then, the loss of agricultural land was quantified using Arc GIS software. Visualizations of the gains and losses in agricultural land and the spatial trends of agricultural land losses were created using TerrSet software. The results show that 9600 ha of agricultural land were converted to urban use during 2010–2018, which means that the annual rate of agricultural land loss has tripled and now reaches approximately 1200 ha per year. Decay of executive authority, rapid population growth, real estate market speculation and fragmentation of agricultural land were the main driving factors of agricultural land losses during this period. The results of this research may help decision makers understand the current high rate of agricultural land loss. Hence, appropriate strategies may be adopted to prevent future losses of this valuable land.  相似文献   
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