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1.
Siting service facilities in order to maximize regional coverage is important when budget resources are limited. Various approaches exist for addressing this particular planning problem for discrete or continuous representations of potential facility sites and demand to be served. In cases where both candidate facility sites and service demand are continuous, approaches for maximizing regional coverage have only examined the siting of a single facility. In this article, a geocomputational approach is proposed for addressing multiple facility siting when demand is continuously distributed and facilities may be located anywhere in the region. Emergency warning siren location is used to highlight the developed approach. 相似文献
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提出一种基于网络Voronoi面域图的最大覆盖选址模型及相应的粒子群优化方法,并应用于城市响应时间敏感型公共服务设施的空间优化。本文考虑设施功能沿交通网络辐射以及需求非均匀分布情形,对设施在网络连续空间上进行布局优化,选址模型采用网络Voronoi面域图划分布局设施的功能辐射域,以启发空间优化最小化重叠覆盖。模型同时顾及了设施利用率的最大化,规定设施对给定距离以内的需求实行的完全服务覆盖和对给定距离以外的需求实行随距离衰减的部分服务覆盖。本研究提出基于遗传机制和广义Voronoi图改进的粒子群算法以提高其空间优化性能,通过对南京市消防站最大覆盖空间优化实验表明,该研究取得了较为理想的结果,可应用于城市化区域应急设施最大覆盖空间优化。 相似文献
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Pranab K. Roy Chowdhury Jeanette E. Weaver Eric M. Weber Dalton Lunga St. Thomas M. LeDoux Amy N. Rose 《International Journal of Digital Earth》2020,13(1):119-135
ABSTRACTUrban areas presently consume around 75% of global primary energy supply, which is expected to significantly increase in the future due to urban growth. Having sustainable, universal energy access is a pressing challenge for most parts of the globe. Understanding urban energy consumption patterns may help to address the challenges to urban sustainability and energy security. However, urban energy analyses are severely limited by the lack of urban energy data. Such datasets are virtually non-existent for the developing countries. As per current projections, most of the new urban growth is bound to occur in these data-starved regions. Hence, there is an urgent need of research methods for monitoring and quantifying urban energy utilization patterns. Here, we apply a data-driven approach to characterize urban settlements based on their formality, which is then used to assess intra-urban urban energy consumption in Johannesburg, South Africa; Sana’a, Yemen; and Ndola, Zambia. Electricity is the fastest growing energy fuel. By analyzing the relationship between the settlement types and the corresponding nighttime light emission, a proxy of electricity consumption, we assess the differential electricity consumption patterns. Our study presents a simple and scalable solution to fill the present data void to understand intra-city electricity consumption patterns. 相似文献
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Area coverage maximization in service facility siting 总被引：3，自引：2，他引：1
Traditionally, models for siting facilities in order to optimize coverage of area demand have made use of discrete space representations
to efficiently handle both candidate facility locations and demand. These discretizations of space are often necessary given
the linear functional forms of many siting models and the complexities associated with evaluating continuous space. Recently,
several spatial optimization approaches have been proposed to address the more general problem of identifying facility sites
that maximize regional coverage for the case where candidate sites and demand are continuously distributed across space. One
assumption of existing approaches is that only demand falling within a prescribed radius of the facility can be effectively
served. In many practical applications, however, service areas are not necessarily circular, as terrain, transportation, and
service characteristics of the facility often result in irregular shapes. This paper develops a generalized service coverage
approach, allowing a sited facility to have any continuous service area shape, not simply a circle. Given that demand and
facility sites are assumed to be continuous throughout a region, geometrical properties of the demand region and the service
facility coverage area are exploited to identify a facility site to optimize the correspondence between the two areas. In
particular, we consider the case where demand is uniformly distributed and the service area is translated to maximize coverage.
A heuristic approach is proposed for efficient model solution. Application results are presented for siting a facility given
differently shaped service areas.
相似文献
| Alan T. MurrayEmail: |
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GIS与模糊数学理论在商服中心空间选址中的应用 总被引：1，自引：1，他引：0
城市商服中心空间位置选择的好坏,直接关系到商服中心能否最大限度的发挥其效用和实现其自身的利益或价值。在利用城市地理信息系统,获取若干可行商服中心地址样本的基础上,采用特尔菲法确定影响选址的因素和它们的权重,并采用贴近度的方法比较被选地址与理想目标的接近程度,由此来确定备选地址的优劣次序,选择最佳的地址。 相似文献
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The location requirements for emergency callers outside urban areas can hardly be fulfilled without global navigation satellite
systems (GNSS). Consequently, interest in positioning techniques based on use of a GNSS such as GPS or on the cellular network
infrastructure itself is growing rapidly in the mobile-telephone community. Moreover, the increasing demand for commercial
location-based services (LBS) has driven cellular-phone and network manufacturers to focus on positioning solutions which
are even more accurate than the regulatory mandates for positioning of emergency callers. One example of these upcoming LBS
is our PARAMOUNT project, which aims at improving user-friendly info-mobility services for hikers and mountaineers by combining
wireless communications (GMTS), satellite navigation (GNSS) and geographic information systems (GIS), based on a mobile client/server
architecture. The availability of mobile phones or PDAs with combined GNSS and cellular network-based wireless communication
on a high integration level is one primary demand of such LBS applications. Based on this, we will give some initial answers
to the question of whether mobile handset architecture synergies exist for the combination of GNSS with wireless location
in CDMA cellular wireless networks. In order to identify synergies, we will outline similarities and differences between wireless
communication and satellite navigation. In this respect, we pay particular attention to the so-called RAKE receiver architecture
employed in mobile CDMA cellular handsets. Our initial investigations will show that the RAKE receiver architecture, on which
mobile CDMA cellular handsets are based, will most likely be the one most suitable for achieving synergies between the two
positioning techniques within the same mobile handset architecture. Consequently, several receiver components could be used
to handle both types of signals (navigation and communications), resulting in a reduction of manufacturing costs and in a
decrease in energy consumption.
Electronic Publication 相似文献
8.
中国的国民经济和社会发展规划、土地利用总体规划以及城乡规划都是法定规划,但由于规划主体、技术标准和编制办法、实施手段和监督机制等的不同,导致"三规分离"、各个规划之间相互冲突的问题较为突出。虽然国家为了消除冲突,正在开展"三规合一"的有关工作,但缺乏有关技术手段的支持。本文以地理信息科学为出发点,对地理过程建模在国内外研究中的应用进行了总结,阐述了地理模拟与优化的框架体系可以成为目前中国正在进行的"三规合一"工作的重要理论和方法支撑。 相似文献
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This research develops a clustering‐based location‐allocation method to the Capacitated Facility Location Problem (CFLP), which provides an approximate optimal solution to determine the location and coverage of a set of facilities to serve the demands of a large number of locations. The allocation is constrained by facility capacities – different facilities may have different capacities and the overall capacity may be inadequate to satisfy the total demands. This research transforms this special location‐allocation problem into a clustering model. The proposed approach has two parts: (1) the allocation of demands to facilities considering capacity constraints while minimizing the cost; and (2) the iterative optimization of facility locations using an adapted K‐means clustering method. The quality of a location‐allocation solution is measured using an objective function, which is the demand‐weighted distance from demand locations to their assigned facilities. The clustering‐based method is evaluated against an adapted Genetic Algorithm (GA) alternative, which integrates the allocation component as described above but uses GA operations to search for ‘optimal’ facility locations. Experiments and evaluations are carried out with various data sets (including both synthetic and real data). 相似文献
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随着现代社会从信息化时代向智能化时代发展,导航通信探测信号的数量急剧增长,指标要求也日益提高,在有限的频谱资源、设备重量、体积与功耗约束下,人们对资源共享多功能一体化信号的需求愈发迫切. 如何通过灵活的信号设计实现资源高效利用和功能动态调整,是该领域当前亟待解决的难题. 本文首先提出了基于“积木单元”思想的信号设计框架,将信号表征为信号矢量和波形基函数的形式,选择基函数的系数组合重构信号矢量,就可以等价地表示对应的信号设计,从而将波形域的信号优化设计转换为信号空间的矢量优化问题. 进一步,分析了传统的信号评估方法,在所提的一体化信号设计框架下推导了导航、通信、探测信号度量准则. 最后,提出了一体化信号度量准则,为信号设计提供了可解释、可量化的优化目标,并讨论了一体化信号设计需要考虑的部分约束,包括能量约束、电磁频谱约束、峰均比等. 相似文献
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One of the simplest location models in terms of its constraint structure in location‐allocation modeling is the location set‐covering problem (LSCP). Although there have been a variety of geographic applications of the set‐covering problem (SCP), the use of the SCP as a facility location model is one of the most common. In the early applications of the LSCP, both potential facility sites as well as demand were represented by points discretely located in geographic space. The advent of geographic information systems (GIS), however, has made possible a greater range of object representations that can reduce representation error. The purpose of this article is to outline a methodology using GIS and K = 3 central place lattices to solve the LSCP when demand is continuously distributed over a bounded area and potential facility sites have not been defined a priori. Although, demand is assumed to exist over an area, it is shown how area coverage can be accomplished by the coverage of a point pattern. Potential facility site distributions based on spacings that are powers of one‐third the coverage distance are also shown to provide more efficient coverage than arbitrarily chosen spacings. Using GIS to make interactive adjustments to an incomplete coverage also provides an efficient alternative to smaller spacings between potential facility sites for reducing the number of facilities necessary for complete coverage. 相似文献
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分析了全球定位系统(GPS)、捷联惯导系统(SINS)和无线定位技术(WLAN)在城市复杂环境下室内外定位时的优缺点,提出了在城市复杂环境下采用基于卡尔曼滤波松组合的SINS／GPS组合导航定位方式,在室内环境下时,单独使用WLAN无线定位技术时易受室内复杂环境的影响,比如天花板、墙壁造成的多径效应,在传播过程中易受相近频段电器的干扰等等;提出了采用基于卡尔曼滤波的SINS／WLAN的组合导航定位技术来实现,从而实现更加平滑的导航定位结果。同时兼顾全组合导航系统高精度、低功耗、小型化的要求,设计出基于TMS320C6713和FPGA架构的嵌入式导航计算机平台。通过该平台系统的搭建,能够有效解决人们对泛在位置服务的需求问题。 相似文献
15.
Yousef Sakieh Abdolrassoul Salmanmahiny Seyed Hamed Mirkarimi Sepideh Saeidi 《国际地球制图》2017,32(8):853-873
This study develops an informed modelling approach that follows a bottom-up planning strategy to define plausible urban growth scenarios. In this case, landscape aesthetics suitability of the area was first generated using multi-criteria evaluation method. Then, a buffer zone of 1 km was considered to extract the average values of aesthetics suitability scores surrounding urban patches with medium physical size (10–30 hectares). The averaged values were considered as the dependent variable. In the next step, landscape metrics of these urban patches, as explanatory variables, were also computed to measure compositional and configuration-based attributes of urban clusters. Bivariate associations (Pearson correlation analysis) and statistical relationships (linear regression algorithm) between landscape metrics and their associated aesthetics values were measured and modelled. According to the results, both composition and configuration values are significantly correlated to the dependent variable in which configuration-based attributes depicted a stronger explanatory power. 相似文献
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The growing importance of urbanization in Canada highlights the need for nationally consistent information on major cities to support effective policy development. A spatially-explicit database, the Canadian Urban Land-Use Survey (CUrLUS), is described. It is a comprehensive source of integrated contemporary land-cover/land-use, demographic and socio-economic information as well as historic land use characterizations from earlier federal initiatives. Satellite remote sensing plays a key role in the form of provision of Landsat-based thematic classifications. The utilization of CUrLUS is illustrated in the quantification of transportation-related energy sustainability indicators, namely, density, urban compactness and land-use mix. The latter shows the greatest promise, being significantly correlated to both work-related median travel distance and percent private vehicle use. Urban transportation is complex and it is argued that indicators based solely on statistical and spatial analysis methodologies are limited in abilities to directly address specific components of this issue, for example, energy consumption. It is recommended that more sophisticated, model-enhanced indicators be developed. We also demonstrate that the land-use/urban-form information of CUrLUS will be a cornerstone in this endeavour. 相似文献
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针对定位、导航、授时、遥感、通信一体的天基信息实时服务系统对遥感信息高时间分辨率获取的需求,提出了基于改进粒子群优化（particle swarm optimization,PSO）算法的遥感卫星星座优化设计方法。基于6N和3+4P星座构型,以重访时间间隔作为优化目标,采用改进的PSO算法对星座优化模型进行求解,分别针对全球覆盖和区域覆盖任务进行了仿真对比试验。仿真结果表明,提出的方法适用于低轨遥感卫星星座设计,满足高时间分辨率要求。 相似文献
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Abstract With the availability of high‐resolution satellite imagery featuring as high as 1 meter resolution in the panchromatic mode and 3‐meter resolution in the multispectral mode, there is an interest by many new commercial and public service applications such as cellular telephones coverage area design, urban/land cover planning, and real estate marketing to extract features from images automatically. To that end, the demand for unsupervised classification techniques is growing. In this paper, the Maximum Likelihood (ML) and Maximum A prior Probability (MAP) algorithms are used as decision rules to find boundaries of classes computed by the Iterative Self‐Organizing Data (ISOADATA) algorithm. Different satellite images with different resolutions were used to experiment with these algorithms. The results of comparing and analyzing the algorithms revealed that MAP‐ISODATA performed better than ML‐ISODATA even when the same initial matrix was used. It was shown that there was no significant difference between ML‐ISODATA and MAP‐ISODATA in terms of accuracy. It was also realized that better results could be obtained if homogenous initialization strategies were used. 相似文献
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This article proposes a grey wolf optimizer (GWO) and cellular automata (CA) integrated model for the simulation and spatial optimization of urban growth. A new grey wolf‐inspired approach is put forward to determine the urban growth rules of CA cells by using the GWO algorithm, which is suitable for solving optimization problems. The inspiration for GWO comes from the social leadership of wolf groups, as well as their hunting behavior. The GWO‐optimized urban growth rules for CA describe the relationship between the spatial variables and the urban land‐use status for each cell in the formation of “if–then.” The GWO algorithm and CA model are then integrated as the GWO–CA model for urban growth simulation and optimization. By taking Nanjing City as an example, the simulation accuracy in terms of urban cells is 86.6%, and the kappa coefficient is 0.715, indicating that the GWO algorithm is efficient at obtaining urban growth rules from spatial variables. The validation of the GWO–CA model also illustrates that it performs well in terms of the simulation and spatial optimization of urban growth, and can further contribute to urban planning and management. 相似文献
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城市空间运行的出租车产生大量的OD数据,数据的时序呈现周期性特点,客观反映人们的出行行为模式,本文采用谱聚类算法对北京五环区域内各空间单元的出行特征及其相似性进行探究。由于空间单元的时空行为特征受空间邻域和功能区划的影响,研究添加邻域因子和功能区因子以改进时间序列的相似性度量方法,从而实现时间序列谱聚类算法的空间和功能区拓展,进而增加人们对不同时空条件下出行行为特征的了解,以便对不同空间单元提供差异性服务,如不同时段公交的发车频次、动态调整商场营业时间、不同时空环境出租车候车点的实时变换、调控和优化不同区域服务保障等,将有助于降低城市能耗,更加合理地利用资源,也有助于居民实现智慧生活。 相似文献