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1.
Precise, automatic and fast method for vanishing point detection 总被引：1，自引：0，他引：1
A new automated approach for vanishing point detection in images of urban scenes is described. This method is based on the theorem of Thales. The main contribution of this paper is the automatic and simultaneous detection of all vanishing points of the image, achieved by converting this problem into the detection of circles in a complex cloud of points, in which each point corresponds to a segment and is associated with an uncertainty. This extraction of circles uses a RANSAC method, modified to improve its speed by using accumulation techniques (Hough transform or otherwise). This robust estimation is then refined by least squares error propagation using the individual variances of each segment. The algorithm is robust, its accuracy is optimised and it is entirely automatic. Its successful operation has been tested on a large number of images of varied urban scenes. 相似文献
2.
Bahram Saeidian Abbas Rajabifard Behnam Atazadeh Mohsen Kalantari 《Transactions in GIS》2023,27(6):1724-1747
In underground environments, survey elements such as survey points and observations provide the information required to define legal boundaries. These elements are also used to connect underground legal spaces to a geodetic survey network. Due to the issues of current 2D approaches for managing underground cadastral data, prominent 3D data models have been extended to support underground land administration. However, previous studies mostly focused on defining underground legal spaces and boundaries, with less emphasis on survey elements. This research aims to extend CityGML to support underground cadastral survey data. The proposed extension is based on the survey elements elicited from underground cadastral plans, which is then implemented for an underground case study area in Melbourne, Australia. This extension integrates underground survey data with legal and physical data in a 3D digital environment and provides an improved representation of survey elements, facilitating the management and communication of underground cadastral survey data. 相似文献
3.
Seismic evaluation of rocking structures through performance assessment and fragility analysis 总被引：2，自引：2，他引：0
Numerical studies have been conducted for low- and medium-rise rocking structures to investigate their efficiency as earthquake-resisting systems in comparison with conventional structures. Several non-linear time-history analyses have been performed to evaluate seismic performance of selected cases at desired ground shaking levels, based on key parameters such as total and flexural story drifts and residual deformations. The Far-field record set is selected as input ground motions and median peak values of key parameters are taken as best estimates of system response. In addition, in order to evaluate the probability of exceeding relevant damage states, analytical fragility curves have been developed based on the results of the incremental dynamic analysis procedure. Small exceedance probabilities and acceptable margins against collapse, together with minor associated damages in main structural members, can be considered as superior seismic performance for medium-rise rocking systems. Low-rise rocking systems could provide significant performance improvement over their conventional counterparts notwithstanding certain weaknesses in their seismic response. 相似文献
4.
As natural and man-made disasters have been increasing, interest in preventing crises and/or mitigating the associated consequences has been growing as well. When dealing with predictable disasters, there is a limited time for effective response, and people should be evacuated in a short time to minimize the fatalities. In such extraordinary situations, attention should be given to making better use of existing infrastructure. The aim of this study is to present a model for optimizing street directions in order to increase the outbound capacity of the network. However, because of the magnitude of the problem, an optimal solution cannot be reached through ordinary methods. Hence, the simulated annealing algorithm, which is a meta-heuristic technique, is used. Computational results on a case study demonstrate that this technique yields considerable improvement in the objective function of the problem which is total travel time of road network users.
相似文献5.
Spatio-temporal analysis of crime by developing a method to detect critical distances for the Knox test 总被引：1，自引：0，他引：1
Mohsen Kalantari Bamshad Yaghmaei Somaye Ghezelbash 《International journal of geographical information science》2016,30(11):2302-2320
The present study examined and compared spatio–temporal interaction of the theft of car parts, shop burglary and motorcycle theft in the central business district (CBD) of the city of Zanjan in Iran. The Knox test was selected to detect spatio–temporal interaction. This test has been criticized as being subjective because the selection of critical distances is arbitrary; thus, a method is proposed to detect critical distances in the Knox test using the mean distance, natural breaks classification of nearest neighbour (NN) distance and Ripley’s k function. Results show obvious differences between the spatio-temporal clusters of the three sets of crimes. They also indicate that changing the spatial cut-offs within a cluster creates different temporal patterns. Of the three criteria for determining critical distances, NN classification based on natural breaks showed more interactions than the other methods. 相似文献
6.
Natural Resources Research - In this study, ZnO nanoparticles were modified with rice bran. Synthesis and production of ZnO nano-particles is highly important due to the use of rice bran. In... 相似文献
7.
Site selection and cost-benefit analysis for artificial recharge in the Baghmalek plain, Khuzestan Province, southwest Iran 总被引：2，自引：2，他引：0
Nasrollah Kalantari Kazem Rangzan Satish Shripad Thigale Mohammad Hosein Rahimi 《Hydrogeology Journal》2010,18(3):761-773
Available hydrogeological data for the Baghmalek aquifer, southwest Iran, suggest that in order to counter progressive depletion of groundwater, but at the same time meet the growing demand on groundwater resources, artificial recharge should be considered. The success of artificial recharge schemes requires the integration of many types of data and information. The prime prerequisite in establishing an artificial recharge scheme using the surface spreading technique is identification of a suitable site. Therefore, an integrated investigation, including a detailed assessment of surface and sub-surface geology, and hydrogeological surveys were undertaken. The potential of harvesting storm waters, considering their quality and suspended loads, has been evaluated. Using this background, three sites (including basins and check dam) for artificial recharge are suggested in the north and northeast of the area, where the thickness of coarse alluvium is greatest. On the basis of the collected data, (1) the rate of recharge that can be achieved at the three sites is approximately 2.2 million m3 per year, (2) the cost–benefit ratio is 1:1.32, and (3) the analysis suggests that the project could recover the investment within 3 years. 相似文献
8.
Saeid Kalantari Reza Safarzadeh Ramhormozi Yunli Wang Sun Sun Xin Wang 《Transactions in GIS》2023,27(4):996-1020
Trailer allocation and truck routing are critical components of truck transportation management. However, in real-world applications, inter-influence between selecting the best trailers and trucks, strict fulfillment of Pickup or Delivery (PD) orders, and the size of the fleet are some of the challenges that need to be dealt with in a large truck company. In addition, trailer allocation and truck routing problems are considered to be NP-hard combinatorial optimization (CO) problems. Therefore, we use deep reinforcement learning (DRL), which has the capability of solving routing problems with a single set of hyperparameters. This is significant progress toward finding strong heuristics for a special case of the trailer allocation to customers and truck routing problem presented in this article. Given a set of trailers, trucks, customers, and orders we propose a novel two-phase framework based on Bipartite Graph Assignment (BGA) and attention-based DRL to minimize the total traveling distance traveled from trucks to trailers and then to customers. The BGA heuristic finds the minimum traveling distance from the trailers to the customers based on the edge information and the encoder-decoder helps DRL to get useful node and graph feature representations and trains the model to find the proper solutions for the trailer allocation and truck routing problem. Our experiments on three different problem sizes showcase the effectiveness of ARTT-DRL. The results indicate that ARTT-DRL produces desirable outcomes and has strong generalization capabilities. 相似文献
9.
Hydrochemical constituents in streams may originate from currently active sources at the surface and/or legacy sources from earlier surface inputs, waste deposits and land contamination. Distinction and quantification of these source contributions are needed for improved interpretation of tracer data and effective reduction of waterborne environmental pollutants. This article develops a methodology that recognizes and quantifies some general mechanistic differences in stream concentration and load behavior versus discharge between such source contributions. The methodology is applied to comparative analysis of stream concentration data for chloride (Cl−), copper (Cu), lead (Pb), and zinc (Zn), and corresponding data for water discharge, measured over the period 1990–2018 in multiple hydrological catchments (19 for Cl−, 11 for Cu and Zn, 10 for Pb) around the major Lake Mälaren in Sweden. For Cl−, the average load fraction of active sources is quantified to be 19%, and the average active and legacy concentration contributions as 2.9 and 11 mg/L, respectively. For the metals, the average active load fractions at outlets are 1%–3% over all catchments and 9%–14% in the relatively few catchments with mixed metal sources. Average active and legacy concentration contributions are 0.14 and 3.2 μg/L for Cu, 0.05 and 1.5 μg/L for Pb, and 1.4 and 12 μg/L for Zn, respectively. This multi-catchment analysis thus indicates a widespread prevalence of legacy sources, with greater legacy than active concentration contributions for both Cl− and the metals, and active contributions playing a greater role for chloride than for the metals. The relatively simple first-order methodology developed and applied in the study can be used to screen commonly available stream monitoring data for possible distinction of active and legacy contributions of any hydrochemical constituent in and across various hydrological catchment settings. 相似文献
10.
Karim Zadeh Zarin Ghafory-Ashtiany Mohsen Kalantari Afshin Shokuhirad Sahar 《Bulletin of Earthquake Engineering》2022,20(11):5905-5942
Bulletin of Earthquake Engineering - One of the main components for developing regional seismic risk models is the fragility functions of common building types. Due to the differences between the... 相似文献