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Dynamic service area sizing in urban delivery
We consider an urban instant delivery environment, e.g., meal delivery, in which customers place orders over the course of a day and are promised delivery within a short period of time after an order is placed. Deliveries are made using a fleet of vehicles, each completing one or more trips during the day. To avoid missing delivery time promises as much as possible, the provider manages demand by dynamically adjusting the size of the service area, i.e., the area in which orders can be delivered. The provider seeks to maximize the number of orders served while avoiding missed delivery time promises. We present three techniques to support the dynamic adjusting of the size of the service area which can be embedded in planning and execution tools that help the provider achieve its goal. First, we learn the functional dependency between expected demand and the service area that can be supported with the fleet of vehicles. Second, we use value function approximation to improve an initial service area sizing plan for the day based on expected demand. Finally, we introduce a correction mechanism to dynamically adjust the service area sizing plan in response to observed realized demand. Extensive computational experiments demonstrate the efficacy of the techniques and show that dynamic sizing of the service area can increase the number of orders served significantly without increasing the number of missed delivery time promises.
Journal Article
The paradox of preservation : wilderness and working landscapes at Point Reyes National Seashore
\"Point Reyes National Seashore has a long history as a working landscape, with dairy and beef ranching, fishing, and oyster farming; yet, since 1962 it has also been managed as a National Seashore. The Paradox of Preservation chronicles how national ideals about what a park 'ought to be' have developed over time and what happens when these ideals are implemented by the National Park Service (NPS) in its efforts to preserve places that are also lived-in landscapes. Using the conflict surrounding the closure of the Drakes Bay Oyster Company, Laura Alice Watt examines how NPS management policies and processes for land use and protection do not always reflect the needs and values of local residents. Instead, the resulting landscapes produced by the NPS represent a series of compromises between use and protection--and between the area's historic pastoral character and a newer vision of wilderness. A fascinating and deeply researched book, The Paradox of Preservation will appeal to those studying environmental history, conservation, public lands, and cultural landscape management, or to those looking to learn more about the history of this dynamic California coastal region\"--Provided by publisher.
Book
Performance evaluation of Galileo high accuracy service for PPP ambiguity resolution
The Galileo high accuracy service (HAS) is now available to users worldwide for precise point positioning (PPP). PPP ambiguity resolution (AR) can further improve precise positioning performance. To date, few studies have focused on PPP AR based on HAS products at the preliminary stage (Phase 1). In this study, we first obtained the HAS precise satellite orbit and clock products by decoding HAS correction data from March 11 to 17, 2023. Then the wide-lane (WL) and narrow-lane (NL) fractional cycle biases (FCB) were estimated using HAS products while the real-time CNT products from Centre National D'Etudes Spatiales (CNES) were also used for comparison. It is noted that only Galileo FCB was estimated, although HAS provided corrections for both GPS and Galileo systems, which aim to prove the efficiency of Galileo-only PPP AR. Afterward, the self-estimated FCBs were evaluated by the posterior residuals using over 160 MGEX stations. Moreover, performance comparison with respect to geographic location as Galileo HAS provides different services to different areas is also conducted. The stations were grouped into two areas, i.e., HAS service area and non-service area. We found that it is difficult for stations outside HAS service area to achieve Galileo HAS PPP AR using the current HAS product due to the poor quality of HAS-NL FCBs. Finally, we selected 20 testing stations to evaluate the HAS and CNT PPP AR performance using Galileo system under static and simulated kinematic situations in HAS service area. For static testing, the results show that the average improvement for fixed solution of HAS was 28.7%, 12.2%, 13.5%, 20.7% and 16.2% in the east, north, up, 2D and 3D directions, respectively, while that of CNT was 39.6%, 29.8%, 19.9%, 37.3% and 26.0%, respectively. In the simulated kinematic testing, the results show that the average improvement for fixed solution of HAS was 12.3%, 13.0%, 5.7%, 12.6% and 7.6% in the east, north, up, 2D and 3D directions, respectively, while that of CNT was 8.2%, 6.1%, 3.3%,7.1% and 4.6%, respectively. In addition, we found that the fixed solutions of HAS from stations located in core areas show better improvement. The above results show that PPP AR for Galileo system can be performed in HAS service area using the HAS product in Phase 1. However, the successful fixing of ambiguity is time-consuming. This issue may be addressed in subsequent phases of HAS products (Phase 2) as well as by processing the ambiguity of both GPS and Galileo together.
Journal Article
The atlas of us
Atlas James has lost her way. In a last-ditch effort to pull her life together, she's working on a community service program rehabbing trails in the Western Sierras. The only plus is that the days are so exhausting that Atlas might just be tired enough to forget that this was one of her dad's favorite places in the world. Before cancer stole him from her life, that is. Using real names is forbidden on the trail. So Atlas becomes Maps, and with her team--Books, Sugar, Junior, and King--she heads into the wilderness. As she sheds the lies she's built up as walls to protect herself, she realizes that four strangers might know her better than anyone has before. And with the end of the trail racing to meet them, Maps is left counting down the days until she returns to her old life--without her new family, and without King, who's become more than just a friend.
Book
Exploring Spatial Distribution of Urban Park Service Areas in Shanghai Based on Travel Time Estimation: A Method Combining Multi-Source Data
Due to a growing appreciation for the ecological and recreational benefits of public green spaces, the evaluation of urban parks’ service efficiency, as well as citizens’ behavioral preferences for daily recreation, have become an increasing academic focus. However, due to the lack of empirical approaches, existing research on exploring park service areas has been simplified by their use of Euclidean distance or buffer sets by simulation, ignoring the fact that the likelihood of citizens visiting urban parks is time sensitive. Utilizing mobile signaling data and web map services, this study proposes an approach to estimating the travel times of park visitors and analyzing the characteristics of park service areas from the perspective of actual time consumption. Taking Shanghai as a case study, this research firstly identified the time–cost decay of parks with different areas and locations. A comparison analysis was then used to examine the spatial relationship between park service areas and their accessibility defined by time consumption. The results show that (1) urban parks in Shanghai have larger mean service radii than existing planning guidelines, and park service areas were significantly influenced by park locations; (2) people have a great preference for urban parks whose travel times by public transit are under 40 min, and they have no desire to visit parks located within or outside the Middle Ring Road when the travel times reach 60 min and 75 min, respectively; (3) the shapes of park service areas are consistent with the high-accessibility districts defined by time thresholds, in spite of some differences caused by citizens’ choices. These findings provide an effective tool for evaluating the actual characteristics of park recreational services, along with direct implications for policymakers aiming to establish effective strategies for improving the accessibility and vitality of urban parks.
Journal Article
Merging geographic regions for the analysis of the cardiological rehabilitation care system in Hungary
Background
Identifying spatial patterns or anomalies in medical care related administrative data is a valuable asset to plan the care system. However, the applicability of any results depends on the statistical robustness and spatial resolution of the analysis.
Methods
This study proposes a new method for designing the spatial units for a country-wide analysis, based on the iterative merging of the postal code areas. The method aims to find a trade-off between fine spatial resolution and districts with a statistically relevant number of episodes, also considering the homogeneity of the districts. The method is applied for the spatial analysis of the cardiological rehabilitation care system in Hungary over an 8-year-long period, with the cardiological rehabilitation rate (RR) after acute cardiac events as the dependent variable. We consider two cardiological episode types and perform two separate analyses throughout the study. A voting scheme is used to define the
de facto
service areas of the dominant providers. Homogeneous spatial clusters with high and low RR values are compared to the boundaries of the service areas using spatial correlation.
Results
The proposed merging method can provide a significantly finer resolution than a simple spatial approach, and the border zones become thinner and clearer between contiguous
de facto
dominant providers. The spatial analysis found strong clustering with a global Moran I index of 0.80 and 0.85, respectively, and very large regional differences, especially in rural areas of the country, which is consistent with inequities in access or referral pathways. The boundaries of rehabilitation rate anomalies generally match with the dominant service areas of the dominant providers, suggesting that the differences are linked with the anomalies in the professional practice of the providers.
Conclusions
The proposed method proved a useful tool for the spatial analysis of the cardiological rehabilitation network. The method is not specific to the local culture, and it is directly applicable in any other healthcare domain with several service providers and for which population-level, geographically referenced data is available. More research using more elaborate data sources would be needed to understand the root causes of the anomalies detected in the study.
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Journal Article
Accessibility assessment of urban public services using GIS-based network analysis: a case study in Eskişehir, Türkiye
The rapid growth of urbanization and the growing need for fair and equitable distribution of urban services is one of the important issues and challenges for urban planners and managers. Eskişehir city has been experiencing rapid urbanization in recent decades. This can lead to imbalances in the distribution of public services. The purpose of this study is to determine the coverage radius and spatial distribution of some public services as well as the location-allocation of new facilities in Eskişehir city. For this purpose, data related to some services such as fire stations, emergency centers, and urban parks were collected, preprocessed, and analyzed using network analysis in the Geographic Information Systems (GIS) environment. Service area and location-allocation analyses were applied. The findings of this study showed that the majority of the city population has access to emergency health centers within a 10-min drive time. However, Eskişehir city center does not have a sufficient distribution of fire stations and urban parks in terms of service coverage. Significant parts of the city are out of the range of fire stations at optimum response time (3–4 min). The study showed that the amount of green space per person is about 8.2 m2. Green spaces in some neighborhoods were found to have been inadequately distributed in relation to population. For this purpose, using GIS-based location-allocation network analysis, some suggestions have been presented to fill the service area gaps and solve the distribution problem by using the appropriate algorithm. The research provides valuable insights for urban managers and planners, emphasizing the need for accurate and effective management of urban areas using GIS technology.
Journal Article
A new decade of uses for geographic information systems (GIS) as a tool to research, measure and analyze library services
PurposeThe purpose of this paper is to explore library research that uses geographic information systems (GIS) as a tool to evaluate library services and resources to ascertain current trends and establish future directions for this growing research area.Design/methodology/approachThe study searched full text for geographic information systems in two databases: Library and Information Science Source (LISS) and Library, Information Science and Technology Abstracts (LISTA), replicating the method used in a prior literature review. The titles and abstracts of the search results were analyzed to gather only the research that used GIS as a tool to measure and analyze library services.FindingsThis study found growth in the last decade for library research using GIS. There remain two ways the tool is primarily used: to analyze service areas and to manage facilities and collections.Practical implicationsThe findings are relevant for library and information science researchers and practitioners because they summarize a specific area of research that has grown and changed and that still has potential to be used more widely. Using GIS in practice and research could benefit all library users and nonusers because spatial analysis facilitates more precise and informed delivery of services and resources.Originality/valueThe paper provides future directions for use of GIS in library research and attempts to define subdivisions within this research area to clarify the area for researchers and practitioners.
Journal Article
A Quantitative Study on the Identification of Ecosystem Services: Providing and Connecting Areas and Their Impact on Ecosystem Service Assessment
The spatial location relations between service-providing areas and service-demand areas determine the effective provision level of ecosystem services. Some scholars use the term ecological service flow to conceptualize the transmission path, transmission characteristics, and service benefits of the provision-oriented service type between service-providing areas and service-demand areas. A few scholars have characterized the transmission range and spatial unit characteristics of single or several ecosystem service types, such as production services and regulation services between the providing area and demand area based on landscape, region and global scale. The current literature lacks quantitative studies on the spatial location relations between providing areas and demand areas of ecosystem services and the actual level of ecosystem service provision at the municipal scale based on the demand for ecosystem services faced by cities. This study takes Jinan, China, as the research area, quantifies the providing areas, connecting areas and demand areas of seven services—namely, the air purification service, climate regulation service, flood prevention service, water pollution prevention service, water supply service, soil erosion prevention service, and habitat supply service—and analyzes the spatial relation characteristics of each element. On this basis, the Hellwig model is used to quantitatively analyze the impact of service-providing area and service-connecting area on regional overall ecosystem service assessment. The results prove that service-providing areas and service-connecting areas are the key units that affect the level of regional ecosystem service provision. The evaluation of regional ecosystem service provision level is inseparable from the identification of service-providing areas and service-connecting areas and the study of their attributes, characteristics, and spatial relations. Service-providing areas and service-connecting areas should be differentiated when developing strategies to optimize and improve the level of regional ecosystem service provision. Different optimization measures should be formulated according to the differences in unit attributes and service barriers in different areas. The results provide guidance for the optimization of ecosystem services to ensure the efficient and sustainable provision of regional ecosystem services and improve the actual benefits of service-demand groups or service-demand areas.
Journal Article