scholarly journals Spatio-Temporal Visualization Method for Urban Waterlogging Warning Based on Dynamic Grading

2020 ◽  
Vol 9 (8) ◽  
pp. 471
Author(s):  
Jingyi Zhou ◽  
Jie Shen ◽  
Kaiyue Zang ◽  
Xiao Shi ◽  
Yixian Du ◽  
...  

With the acceleration of the urbanization process, the problems caused by extreme weather such as heavy rainstorm events have become more and more serious. During such events, the road and its auxiliary facilities may be damaged in the process of the rainstorm and waterlogging, resulting in the decline of its traffic capacity. Rainfall is a continuous process in a space–time dimension, and as rainfall data are obtained through discrete monitoring stations, the acquired rainfall data have discrete characteristics of time interval and space. In order to facilitate users in understanding the impact of urban waterlogging on traffic, the visualization of waterlogging information needs to be displayed under different spatial and temporal granularity. Therefore, the appropriateness of the visualization granularity directly affects the user’s cognition of the road waterlogging map. To solve this problem, this paper established a spatial granularity and temporal granularity computing quantitative model for spatio-temporal visualization of road waterlogging and the evaluation method of the model was based on the cognition experiment. The minimum visualization unit of the road section is 50 m and we proposed a 5-level depth grading method and two color schemes for road waterlogging visualization based on the user’s cognition. To verify the feasibility of the method, we developed a prototype system and implemented a dynamic spatio-temporal visualization of the waterlogging process in the main urban area of Nanjing, China. The user cognition experiment showed that most participants thought that the segmentation of road was helpful to the local visual expression of waterlogging, and the color schemes of waterlogging depth were also helpful to display the road waterlogging information more effectively.

2011 ◽  
Vol 8 (5) ◽  
pp. 9435-9468 ◽  
Author(s):  
A. Akbari ◽  
F. Othman ◽  
A. Abu Samah

Abstract. Spatial and temporal pattern of rainfall play an important role in runoff generation. Raingauge density influences the accuracy of spatial pattern and time interval influence the accuracy of temporal pattern of storms. Usually due to practical and financial limitation the perfect distribution is not achievable. Several sources of data are used to define the behavior of rainfall over a watershed. Raingauges station, radar operation and satellite sensor are the main source of rainfall estimation over the space and time. Recording raingauges are the most common source of rainfall data in many countries. However raingauge network has not adequate coverage in many watersheds spatially in developing countries. Therefore other global source of rainfall data may be useful for hydrological analysis such as flood modeling. This research assessed the ability of TRMM rainfall estimates for explain the Spatio-temporal pattern of severe storm over Klang watershed which is a hydrologically well instrumented watershed. It was experienced that TRMM rainfall estimates are 35% less than actual data for the investigated events. Due to coarse temporal resolution of TRMM (3 h) compare to gauge rainfall (15 min), significant uncertainty influences identifying the start and end of storm event and consequently their resultant time to peak of flood hydrograph which is extremely important in flood forecasting systems. Due to coarse pixel size of TRMM data, watershed scale is important issue.


2013 ◽  
Vol 726-731 ◽  
pp. 4109-4114
Author(s):  
Jin Song Shi ◽  
Bo Hu ◽  
Hou Cou Sun ◽  
Qin Tao Wang

This paper analyzed the impact of the mountain highway on road domain ecosystems, and defined the concept and content of the road domain ecosystem ecological integration and its relationship with ecosystem health. Based on PSR framework, the ecological integrated measurement model was built. By constructing various subsystems indicators, the road domain ecosystem ecological integration was quantified by using the comprehensive evaluation method. On this basis, this paper divided the ecological integration into four grades: poor, moderate, good and excellent. It provided a theoretical basis for the ecological protection and restoration of the mountain highway construction.


2020 ◽  
Author(s):  
Frederik Tack ◽  
Alexis Merlaud ◽  
Marian-Daniel Iordache ◽  
Gaia Pinardi ◽  
Ermioni Dimitropoulou ◽  
...  

<p>Sentinel-5 Precursor (S-5P), launched in October 2017, is the first mission of the Copernicus Programme dedicated to the monitoring of air quality and climate. Its characteristics, such as the fine spatial resolution, introduce many new opportunities and challenges, requiring to carefully assess the quality and validity of the generated data products by comparison with independent reference observations.</p><p>In the presented study, the S-5P/TROPOMI tropospheric nitrogen dioxide (NO<sub>2</sub>) L2 product (3.5 x 7 km<sup>2 </sup>at nadir observations) has been validated over strongly polluted urban regions based on comparison with coincident high-resolution airborne remote sensing observations (~100 m<sup>2</sup>). Airborne imagers are able to map the horizontal distribution of tropospheric NO<sub>2</sub>, as well as its strong spatio-temporal variability, at high resolution and with high accuracy. Satellite products can be optimally assessed based on airborne observations as a large amount of satellite pixels can be fully mapped in a relatively short time interval, reducing the impact of spatiotemporal mismatches. Additionally, such data sets allow to study the TROPOMI subpixel variability and impact of signal smoothing due to its finite satellite pixel size, typically coarser than fine-scale gradients in the urban NO<sub>2</sub> field.</p><p>In the framework of the S5PVAL-BE campaign, the Airborne Prism EXperiment (APEX) imaging spectrometer has been deployed during four mapping flights (26-29 June 2019) over the two largest urban regions in Belgium, i.e. Brussels and Antwerp, in order to map the horizontal distribution of tropospheric NO<sub>2</sub>. Per flight, 15 to 20 TROPOMI pixels were fully covered by approximately 5000 APEX measurements for each TROPOMI pixel. Mapping flights and ancillary ground-based measurements (car-mobile DOAS, MAX-DOAS, CIMEL, ceilometer, etc.) were conducted in coincidence with the overpass of TROPOMI (typically between noon and 2 PM UTC). The TROPOMI and APEX NO<sub>2</sub> vertical column density (VCD) retrieval schemes are similar in concept. Retrieved NO<sub>2 </sub>VCDs were georeferenced, gridded and intercompared. As strongly polluted areas typically exhibit strong NO<sub>2 </sub>vertical gradients (besides the strong horizontal gradients), a custom TROPOMI tropospheric NO<sub>2 </sub>product was computed and compared as well with APEX by replacing the coarse 1° x 1° a priori NO<sub>2 </sub>vertical profiles from TM5-MP by NO<sub>2</sub> profile shapes from the CAMS regional CTM ensemble at 0.1° x 0.1°.</p><p>Overall for the ensemble of the four flights, the standard TROPOMI NO<sub>2</sub> VCD product is well correlated (R= 0.94) but biased low (slope = 0.73) with respect to APEX NO<sub>2</sub> retrievals. When replacing the TM5-MP a priori NO<sub>2</sub> profiles by CAMS-based profiles, the slope increases to 0.88. When calculating the NO<sub>2</sub> VCD differences, the bias is on average -1.3 ± 1.2 x 10<sup>15</sup> molec cm<sup>-2</sup> or -16% ± 11% for the difference between APEX NO<sub>2</sub> VCDs and the standard TROPOMI NO<sub>2</sub> VCD product. The bias is substantially reduced when replacing the coarse TM5-MP a priori NO<sub>2</sub> profiles by CAMS-based profiles, being -0.1 ± 1.1  x 10<sup>15</sup> molec cm<sup>-2</sup> or -0.1% ± 11%. Both sets of retrievals are well within the accuracy requirement of a maximum bias of 25-50% for the TROPOMI tropospheric NO<sub>2</sub> product for all individual compared pixels.</p>


2013 ◽  
Vol 726-731 ◽  
pp. 4135-4141
Author(s):  
Jin Song Shi ◽  
Bo Hu ◽  
Hou Cai Sun ◽  
Qin Tao Wang

This paper analyzed the concept and content of the road domain ecosystem ecological integration and its relationship with ecosystem health. Based on PSR framework, the ecological integrated measurement model was built, which divided the ecological integration into three subsystems, pressure, state and response. By constructing various subsystems indicators, the road domain ecosystem ecological integration was quantified by using the comprehensive evaluation method. On this basis, the ecological integration index was calculated along the highway at different distances of Yichang to Badong highway. The result shows that the road domain ecosystem ecological integration is relative to the distance on both sides of the highway. In the range of 0-5m, the ecological integration index is only 0.0408, which is gradually rising with distance increasing. To the range of 100-200m, the ecological integration index reaches 0.9343, which is close to the normal ecosystems level. This result is mainly related to the road construction disturbance. When it is closer to the road, the interference intensity is greater and the impact on the ecosystem is more obvious, which leads to the worse ecological integration. Conversely, the ecological integration is better.


2014 ◽  
Vol 14 (20) ◽  
pp. 28231-28268 ◽  
Author(s):  
H. Vogelmann ◽  
R. Sussmann ◽  
T. Trickl ◽  
A. Reichert

Abstract. Water vapor is the most important greenhouse gas and its spatio-temporal variability strongly exceeds that of all other greenhouse gases. However, this variability has hardly been studied quantitatively so far. We present an analysis of a five-year period of water vapor measurements in the free troposphere above Mt. Zugspitze (2962 m a.s.l., Germany). Our results are obtained from a combination of measurements of vertically integrated water vapor (IWV), recorded with a solar Fourier Transform InfraRed (FTIR) spectrometer on the summit of Mt. Zugspitze and of water vapor profiles recorded with the nearby differential absorption lidar (DIAL) at the Schneefernerhaus research station. The special geometrical arrangement of one zenith-viewing and one sun-pointing instrument and the temporal resolution of both instruments allow for an investigation of the spatio-temporal variability of IWV on a spatial scale of less than one kilometer and on a time scale of less than one hour. The SD of differences between both instruments σIWV calculated for varied subsets of data serves as a measure of variability. The different subsets are based on various spatial and temporal matching criteria. Within a time interval of 20 min, the spatial variability becomes significant for horizontal distances above 2 km, but only in the warm season (σIWV = 0.35 mm). However, it is not sensitive to the horizontal distance during the winter season. The variability of IWV within a time interval of 30 min peaks in July and August (σIWV > 0.55 mm, mean horizontal distance = 2.5 km and has its minimum around midwinter (σIWV < 0.2 mm, mean distance > 5 km). The temporal variability of IWV is derived by selecting subsets of data from both instruments with optimal volume matching. For a short time interval of 5 min, the variability is 0.05 mm and increases to more than 0.5 mm for a time interval of 15 h. The profile variability of water vapor is determined by analyzing subsets of water vapor profiles recorded by the DIAL within time intervals from 1 to 5 h. For all altitudes, the variability increases with widened time intervals. The lowest relative variability is observed in the lower free troposphere around an altitude of 4.5 km. Above 5 km, the relative variability increases continuously up to the tropopause by about a factor of 3. Analysis of the covariance of the vertical variability reveals an enhanced variability of water vapor in the upper troposphere above 6 km. It is attributed to a more coherent flow of heterogeneous air masses, while the variability at lower altitudes is also driven by local atmospheric dynamics. By studying the short-term variability of vertical water vapor profiles recorded within a day, we come to the conclusion that the contribution of long-range transport and the advection of heterogeneous layer structures may exceed the impact of local convection by one order of magnitude even in the altitude range between 3 and 5 km.


2020 ◽  
Vol 64 (1-4) ◽  
pp. 1365-1372
Author(s):  
Xiaohui Mao ◽  
Liping Fei ◽  
Xianping Shang ◽  
Jie Chen ◽  
Zhihao Zhao

The measurement performance of road vehicle automatic weighing instrument installed on highways is directly related to the safety of roads and bridges. The fuzzy number indicates that the uncertain quantization problem has obvious advantages. By analyzing the factors affecting the metrological performance of the road vehicle automatic weighing instrument, combined with the fuzzy mathematics theory, the weight evaluation model of the dynamic performance evaluation of the road vehicle automatic weighing instrument is proposed. The factors of measurement performance are summarized and calculated, and the comprehensive evaluation standard of the metering performance of the weighing equipment is obtained, so as to realize the quantifiable analysis and evaluation of the metering performance of the dynamic road vehicle automatic weighing instrument in use, and provide data reference for adopting a more scientific measurement supervision method.


2017 ◽  
Vol 11 (3) ◽  
pp. 255
Author(s):  
Jeky El Boru

Abstract: This research aims to analyze the impact of Janti Flyover Construction toward the growth of layout at Janti Urban Area, including structured space, open space, and linkage. Method used for data collecting are observation, air photograph monitoring, and interview, whereas the analysis method is qualitative description, which is the superimposed method of two layers, that are the layout condition before and after flyover construction. The result shows that the impact of Janti Flyover construction can be seen on building mass (solid), the increasing number of open spaces, including the road network, parking place, and park, whereas the relation between spaces, visually and structurally, can be seen on the growth of buildings which have new shapes and styles, therefore the performance of the overall building does not have a proportional shape. Considering Janti Street at the collective relation, its role is getting stronger as the main frame road network.Keywords: Flyover construction, layout changing, Janti AreaAbstrak: Penelitian ini bertujuan untuk menganalisis pengaruh pembangunan Jalan Layang Janti terhadap perkembangan tata ruang Kawasan Janti, meliputi ruang terbangun, ruang terbuka, serta hubungan antar ruang (“linkage”). Metode pengumpulan data dilakukan melalui observasi, pengamatan foto udara, dan wawancara; sedangkan metode analisis melalui deskripsi secara kualitatif yang berupa “superimposed method” dari dua lapisan kondisi lahan, yakni kondisi tata ruang sebelum dan sesudah pembangunan jalan layang. Hasil penelitian menunjukkan bahwa pengaruh pembangunan Jalan Layang Janti terdapat pada massa bangunan (“solid”), pertambahan ruang terbuka yang berupa jaringan jalan, parkir, dan taman; sedangkan pada hubungan antar ruang ̶ secara visual dan struktural ̶ yakni tumbuhnya bangunan dengan bentuk dan gaya baru, sehingga bentuk tampilan bangunan secara keseluruhan tidak proporsional. Pada hubungan kolektif, Jalan Janti semakin kuat perannya sebagai kerangka utama jaringan jalan.Kata kunci : Pembangunan jalan layang, tata ruang, Kawasan Janti


2013 ◽  
Vol 13 (2) ◽  
Author(s):  
Wisyanto Wisyanto

Tsunami which was generated by the 2004 Aceh eartquake has beenhaunting our life. The building damage due to the tsunami could be seenthroughout Meulaboh Coastal Area. Appearing of the physical loss wasclose to our fault. It was caused by the use dan plan of the land withoutconsidering a tsunami disaster threat. Learning from that event, we haveconducted a research on the pattern of damage that caused by the 2004tsunami. Based on the analysis of tsunami hazard intensity and thepattern of building damage, it has been made a landuse planning whichbased on tsunami mitigation for Meulaboh. Tsunami mitigation-based ofMeulaboh landuse planning was made by intergrating some aspects, suchas tsunami protection using pandanus greenbelt, embankment along withhigh plants and also arranging the direction of roads and setting of building forming a rhombus-shaped. The rhombus-shaped of setting of the road and building would reduce the impact of tsunamic wave. It is expected that these all comprehensive landuse planning will minimize potential losses in the future .


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