Hasil untuk "Metropolitan areas"

Christopher Marquis, Maryann Glynn

Jing Dong, Changzheng Liu, Zhenhong Lin

This paper studies electric vehicle charger location problems and analyzes the impact of public charging infrastructure deployment on increasing electric miles traveled, thus promoting battery electric vehicle (BEV) market penetration. An activity-based assessment method is proposed to evaluate BEV feasibility for the heterogeneous traveling population in the real world driving context. Genetic algorithm is applied to find (sub)optimal locations for siting public charging stations. A case study using the GPS-based travel survey data collected in the greater Seattle metropolitan area shows that electric miles and trips could be significantly increased by installing public chargers at popular destinations, with a reasonable infrastructure investment.

Michael F. Staddon, Natalie A. Dye, Marko Popović et al.

Developing epithelial tissues coordinate cell proliferation and mechanical forces to achieve proper size and shape. As epithelial cells tightly adhere together to form the confluent tissue, the distribution of cell areas significantly influences possible patterns of cellular packing and thereby also the mechanics of the epithelium. Therefore, it is important to understand the origin of cell area heterogeneity in developing tissues and, if possible, how to control it. Previous models of cell growth and division have been successful in accounting for experimentally observed area distributions in cultured cells and bacterial colonies, but developing tissues present additional complexity due to self-organized patterns of mechanical stresses that guide morphogenesis. Here, we address this challenge focusing on the D. melanogaster wing disc epithelium. We consider a simple model that couples cell cycle dynamics to tissue mechanics. From time-lapse imaging of the cellular network, we extract all model parameters - cell growth rates, division rates, and mechanical fluctuations - revealing that they all depend on cell size. With these independently measured parameters, our model quantitatively reproduces the observed cell area distribution without any fitting parameters and further predicts tissue pressure gradients, in quantitative agreement with previously published data. Importantly, we find that cell proliferation accounts for 85% of cell area variance, establishing it as the dominant source of packing disorder that influences tissue mechanics and organization.

Yang Yi, Guilian Zhang, Wei Wang et al.

Urban vegetation has important ecological functions such as purifying the air, alleviating the heat island effect and improving the quality of the living environment. Accurately assessing the carbon sink (CSK) of urban vegetation, understanding the spatial and temporal variations in carbon storage (CS) and CSK along the urban–rural gradient, and identifying their driving factors are essential for addressing climate change in cities. This study employed machine learning and geospatial statistical analysis to evaluate CS and CSK in Shanghai, a major metropolitan area in China. The results showed that: (1) From 2015 to 2020, the total CS in Shanghai increased by 1.10 Mt (41.98%), while carbon density (CD) rose by 41.54%. A pronounced gradient was observed in CS and CSK, with 75% of CS concentrated in the suburban area (Ring5). (2) Although suburban regions exhibited a larger total CSK than urban areas, it showed high fluctuation, including negative values and cold spots. In contrast, the central urban area (Ring1) demonstrated stable CSK with no negative values. (3) During the study period, the spatial distribution of CS became more homogeneous, with a reduction in the extent of high-value and low-value regions decreased. The area of the low-value region decreased by more than 50%. CSK cold spots were mainly distributed in the south, while hot spots clustered in the north, with higher index values in cold spot regions. (4) In central area (Ring1), soil conditions were the dominant factor affecting both CS and CSK. Meanwhile, the transition zone (Ring2–Ring4) was influenced by an interplay of natural environmental, socioeconomic, and locational conditions, whereas the suburb (Ring5) was predominantly controlled by climatic factors. All driving factors exhibited interactive enhancement effects, suggesting that improving regional carbon sink capacity requires integrated measures. This study demonstrates that remote sensing inversion and spatial analysis offer effective technical support for dynamic urban carbon assessment and can inform the development of differentiated carbon management policies.

Shimpei Ogawa, Hideki Endo, Masahiro Yoshida et al.

Abstract Aim Possible negative effects of the COVID‐19 pandemic on short‐term postoperative outcomes for colorectal perforation in Japan were examined in this study. Methods The National Clinical Database (NCD) is a large‐scale database including more than 95% of surgical cases in Japan. We analyzed 13 107 cases of colorectal perforation from 2019 to 2021. National data were analyzed, and subgroup analyses were conducted for subjects in prefectures with high infection levels (HILs) and metropolitan areas (Tokyo Met. and Osaka Pref.). Postoperative 30‐day mortality, surgical mortality, and postoperative complications (Clavien–Dindo grade ≥3) were examined. Months were considered to have significantly high or low mortality or complication rates, if the 95% confidence interval (CI) of the standardized mortality (morbidity) ratio (SMR) does not contain 1. Results In the NCD, postoperative 30‐day mortality occurred in 1371 subjects (10.5%), surgical mortality in 1805 (13.8%), and postoperative complications in 3950 (30.1%). Significantly higher SMRs were found for 30‐day mortality in November 2020 (14.6%, 1.39 [95% CI: 1.04–1.83]) and February 2021 (14.6%, 1.48 [95% CI: 1.10–1.96]), and for postoperative complications in June 2020 (37.3%, 1.28 [95% CI: 1.08–1.52]) and November 2020 (36.4%, 1.21 [95% CI: 1.01–1.44]). The SMRs for surgical mortality were not significantly high in any month. In prefectures with HILs and large metropolitan areas, there were few months with significantly higher SMRs. Conclusions The COVID‐19 pandemic had limited negative effects on postoperative outcomes in patients with colorectal perforation. These findings suggest that the emergency system for colorectal perforation in Japan was generally maintained during the pandemic.

Sho Kawano, Paul A. Parker, Zehang Richard Li

Area-level models for small area estimation typically rely on areal random effects to shrink design-based direct estimates towards a model-based predictor. Incorporating the spatial dependence of the random effects into these models can further improve the estimates when there are not enough covariates to fully account for spatial dependence of the areal means. A number of recent works have investigated models that include random effects for only a subset of areas, in order to improve the precision of estimates. However, such models do not readily handle spatial dependence. In this paper, we introduce a model that accounts for spatial dependence in both the random effects as well as the latent process that selects the effects. We show how this model can significantly improve predictive accuracy via an empirical simulation study based on data from the American Community Survey, and illustrate its properties via an application to estimate county-level median rent burden.

María Bugallo Porto, Domingo Morales González, Nicola Salvati et al.

In small area estimation, it is a smart strategy to rely on data measured over time. However, linear mixed models struggle to properly capture time dependencies when the number of lags is large. Given the lack of published studies addressing robust prediction in small areas using time-dependent data, this research seeks to extend M-quantile models to this field. Indeed, our methodology successfully addresses this challenge and offers flexibility to the widely imposed assumption of unit-level independence. Under the new model, robust bias-corrected predictors for small area linear indicators are derived. Additionally, the optimal selection of the robustness parameter for bias correction is explored, contributing theoretically to the field and enhancing outlier detection. For the estimation of the mean squared error (MSE), a first-order approximation and analytical estimators are obtained under general conditions. Several simulation experiments are conducted to evaluate the performance of the fitting algorithm, the new predictors, and the resulting MSE estimators, as well as the optimal selection of the robustness parameter. Finally, an application to the Spanish Living Conditions Survey data illustrates the usefulness of the proposed predictors.

Iñigo Delgado-Enales, Joshua Lizundia-Loiola, Patricia Molina-Costa et al.

The increasingly populated cities of the 21st Century face the challenge of being sustainable and resilient spaces for their inhabitants. However, climate change, among other problems, makes these objectives difficult to achieve. The Urban Heat Island (UHI) phenomenon that occurs in cities, increasing their thermal stress, is one of the stumbling blocks to achieve a more sustainable city. The ability to estimate temperatures with a high degree of accuracy allows for the identification of the highest priority areas in cities where urban improvements need to be made to reduce thermal discomfort. In this work we explore the usefulness of image-to-image deep neural networks (DNNs) for correlating spatial and meteorological variables of a urban area with street-level air temperature. The air temperature at street-level is estimated both spatially and temporally for a specific use case, and compared with existing, well-established numerical models. Based on the obtained results, deep neural networks are confirmed to be faster and less computationally expensive alternative for ground-level air temperature compared to numerical models.

Michael R. Barnes, Eric Watkins

Green spaces comprising natural turfgrass are ubiquitous in urban areas globally and allow for a variety of ecosystem services that benefit nature and people. However, traditional natural turfgrass is often critiqued for the number of inputs (e.g., fertilizer, water) required to maintain it. With those critiques in mind, some cities have turned to artificial turf as an alternative groundcover despite environmental and human health concerns (e.g., heavy metal leaching, volatile organic compounds). Research of artificial turf has been minimal compared with that of the growth of installations, especially related to social aspects of the surface. The current research used an in-person experiential case study of park visitors in the Twin Cities Metropolitan Area of Minneapolis–St. Paul, MN, USA, to investigate how individuals perceived artificial turf compared with natural turfgrass as it relates to potential uses (e.g., resting/relaxing) and beliefs about sustainability (e.g., environmental impacts). Overall, participants preferred natural turfgrass across all uses but two (recreational and organized sports). The largest differences were observed for the use for picnic areas and the use for play areas for pets. Participants also perceived natural turfgrass as more sustainable than artificial turf, corresponding to the contribution to human health and well-being. In contrast, participants equally perceived the use of these surfaces in terms of natural resources. These findings have implications for public land managers, urban planners, city councils, and other stakeholders because they consider the adoption of artificial turf or other possible alternatives (e.g., low-input turfgrasses, bee lawns) to traditional turfgrass in the communities and their sustainability, maintenance, and cost-savings.

Oseyomon John AIGBOKHAN, Oludare Hakeem ADEDEJI, Abiodun Olusegun OLADOYE et al.

In this study, the spatiotemporal dynamics of the urban environment and thermal environment of Benin City are analysed. The maximum likelihood algorithm for land use and land cover (LULC) analysis was used to categorise Landsat images. The relative transfer equation (RTE) and land surface emissivity (LSE) approaches were used to retrieve the land surface temperature (LST), whereas the Cellular Automata-Markov (CA-Markov) algorithm was used to forecast the LULC for 2030. The findings reveal evolving LULC patterns over time. Built-up areas made up 19.66% of the total area in 1990, bare ground made up 9.25%, and vegetation made up 71.08%. Built-up areas reached 23.40% in 2000, bare land reached 12%, and the vegetation cover dropped to 64.16%. In 2010, there was an increase in the proportion of built-up areas to 44.38%, the proportion of bare land increased to 22.20%, and the proportion of vegetation decreased to 33.42%. Built-up areas reached 61.79% in 2020, compared to 22.29% for bare land and 61.79% for vegetation. Regarding the relationship between the fractional vegetation cover (FVC) and LST, for the years 1992, 2002, 2012, and 2022, R2 is equal to 0.87097, 0.84598, 0.83957, and 0.71838, respectively. Conversely, for the LST and the normalised difference built-up index (NDBI), the R2 values were 0.5975, 0.73876, 0.86615, and 0.90368 for 1992, 2002, 2012, and 2022 respectively. In conclusion, this study evaluates Benin City’s metropolitan setting and thermal environment. According to the LULC study, there are more built-up areas and less vegetation. The impact of the changing land cover on urban thermal features is shown through correlation analysis, which links more built-up regions to higher LSTs. These results can support urban design efforts to lessen the effects of climate change. Examining the distribution of the LST and its associations with particular land cover types was the major goal of this study. Future research will undoubtedly use this study as a useful reference when modelling urban terrain and temperature variations.

Medhat Elkelawy, Hagar Alm ElDin Mohamad, Mohamed Samadony et al.

The transportation sector is a major source of worldwide carbon emissions and represents a significant contributor to air quality issues, particularly in metropolitan areas. To address the enormous carburization issues, the transportation sector must embrace low-emission vehicle technology. The team is presently developing a passenger electric hybrid car with the goal of reducing the environmental pollution. Hybrid electric vehicles (HEVs), which have a record of success in lowering hydrocarbon usage, stand as an intermediary technique between fully electric cars and internal combustion engines. In the present work, the conventional gasoline car has been tested on road at different trips condition. The gasoline fuel consumption as well as the SI engine emissions have been tested. A complete Hybrid electric system has been impeded instead of conventional driving gasoline engines and tested at a different charging rate of the battery. A comparison between the tested systems shows increased fuel efficiency as a key advantage of using HEVs technology. However, there are still unresolved issues about the system's energy reliability. HEVs emit up to 21.0, 5.8, 9.0-, and 23.3-times lower NOx, UHC, CO, and particle number emissions than comparable gasoline vehicles. The development of after-treatment systems, enhanced engine management methods and the use of renewable fuels are emerging as research strategic priorities

Bowen Ma, Xu Wang

The contradiction between the ecological environment and economic development restricts the sustainable development of Wuhan Metropolitan Area (WMA). As an important carrier of the ecosystem in WMA, the change of ecological space can effectively reflect the ecological environment of WMA. Accordingly, based on various development needs and the Markov-FLUS model, this paper simulated the distribution of ecological space in WMA in 2035 under five scenarios, and discussed the characteristics of landscape structure and ecosystem service value of ecological space under five different scenarios. The results show that the Markov-FLUS model can properly simulate the future distribution of ecological space in WMA. Compared with 2020, the scale of ecological space under the natural development scenario (ND), the balanced and coordinated development scenario (BCD) and the ecological space preference development scenario (ESPD) increases, while the scale of the production space preference development scenario (PSPD) and the living space preference development scenario (LSPD) decreases. In the five scenarios, the areas of ecological spatial change are predominantly concentrated in the central urban area of Wuhan, the urban construction area of Ezhou, Huangshi and Huanggang, and the Dabie Mountain area in the northeast of Huanggang. Under the influence of human activities, the landscape structure of ecological space in WMA tended to be smaller in size, simplersize, simpler in boundary, more dispersed in distribution, and more uneven. Water and forest land play a major role in the ecosystem service value of ecological space in WMA, accounting for more than 95% of the value, and mostly play hydrological and climate regulation functions. The sustainable development and protection of ecological space under the BCD mode can provide reference for the policy implementation of sustainable development of territorial space and regional ecological security in WMA in the future.

Fabrice Baudoin, Nizar Demni, Jing Wang

The monograph is devoted to the study of stochastic area functionals of Brownian motions and of the associated heat kernels on Lie groups and Riemannian manifolds. It is essentially self-contained and as such can serve as a textbook on the theory of Brownian motions and horizontal Brownian motions on manifolds. Emphasis is put on concrete examples which allows us to concretely illustrate the rich and deep interactions between stochastic calculus, Riemannian and sub-Riemannian geometry, the theory of complex and quaternionic symmetric spaces and random matrices.

Limeng Wang, Ranran Yang, Yang Qu et al.

Demand-side management is very critical in China's energy systems because of its high fossil energy consumption and low system energy efficiency. A building shape factor is introduced in describing the architectural characteristics of different functional areas, which are combined with the characteristics of the energy consumed by users to investigate the features of heating load in different functional areas. A Stackelberg game-based optimal scheduling model is proposed for electro-thermal integrated energy systems, which seeks to maximize the revenue of integrated energy operator (IEO) and minimize the cost of users. Here, IEO and users are the Stackelberg game leader and followers, respectively. The leader uses real-time energy prices to guide loads to participate in demand response, while the followers make energy plans based on price feedback. Using the Karush-Kuhn-Tucker (KKT) condition and the big-M method, the model is transformed into a mixed-integer quadratic programming (MIQP) problem, which is solved by using MATLAB and CPLEX software. The results demonstrate that the proposal manages to balance the interests of IEO and users. Furthermore, the heating loads of public and residential areas can be managed separately based on the differences in energy consumption and building shape characteristics, thereby improving the system operational flexibility and promoting renewable energy consumption.

Dirk Siersma

In this paper we study the area function of polygons, where the vertices are sliding along curves. We give geometric criteria for the critical points and determine also the Hesse matrix at those points. This is the starting point for a Morse-theoretic approach, which includes the relation with the topology of the configuration spaces. Moreover the condition for extremal area gives rise to a new type of billiard: the inner area billiard.

J. Fritzsch, M. Tyloo, Ph. Jacquod

Interconnecting power systems has a number of advantages such as better electric power quality, increased reliability of power supply, economies of scales through production and reserve pooling and so forth. Simultaneously, it may jeopardize the overall system stability with the emergence of so-called inter-area oscillations, which are coherent oscillations involving groups of rotating machines separated by large distances up to thousands of kilometers. These often weakly damped modes may have harmful consequences for grid operation, yet despite decades of investigations, the mechanisms that generate them are still poorly understood, and the existing theories are based on assumptions that are not satisfied in real power grids where such modes are observed. Here we construct a matrix perturbation theory of large interconnected power systems that clarifies the origin and the conditions for the emergence of inter-area oscillations. We show that coherent inter-area oscillations emerge from the zero-modes of a multi-area network Laplacian matrix, which hybridize only weakly with other modes, even under significant capacity of the inter-area tie-lines, i.e. even when the standard assumption of area partitioning is not satisfied. The general theory is illustrated on a two-area system, and numerically applied to the well-connected PanTaGruEl model of the synchronous grid of continental Europe.

Dmitry Zhabin

It is shown that fractal dimension can be estimated seeking a solution of functional equation defined for areas of coverages of different scales. The method proposed is compared with widely known way to estimate fractal dimension via linear regression for numbers of ordinary sets, which are used to cover the fractal, and scale size. Due to its simplicity the method described in the article may be useful to get estimation of fractal dimension for 2D time-series.

Juste Raimbault, Michael Batty

Operational urban transport models require to gather heterogeneous sets of data and often integrate different sub-models. Their systematic validation and reproducible application therefore remains problematic. We propose in this contribution to build transport models from the bottom-up using scientific workflow systems with open-source components and data. These open models are aimed in particular at estimating congestion of public transport in all UK urban areas. This allows us building health indicators related to public transport density in the context of the COVID-19 crisis, and testing related policies.

Nataša Pipenbaher, Danijel Ivajnšič, Igor Žiberna et al.

The urban heat island phenomenon (UHI) is a consequence of anthropogenic activity and local climatic conditions. Most UHI studies address large metropolitan areas. However, the data show that UHI magnitude can reach high values even in small urban systems. The study focused on the seasonal dynamics of the UHI magnitude variable (average, maximum and minimum temperature anomaly) in the town of Ljutomer by considering different weather types. Under anticyclonic or advective air circulation pattern, predominantly in summer, UHI magnitude in Ljutomer can reach values comparable to midsize or large urban systems (up to 8°C). The results of such studies are of particular concern in regard to increasing frequency of heat waves as a consequence of climate change, which further increases the already present heat stress in cities all over the Globe.

Behrang Kalantari, Jila Sajadi, Mohammad Taghi Razavia

Objective: One of the most complex social phenomena in today's cities is inequality. This inequality in urban space has led to problems, especially in metropolitan areas. One of these issues and problems is the social exclusion of some citizens in the urban space. The purpose of this paper is to survey urban space in terms of indicators of social exclusion. Methods: The present paper is applied in terms of purpose and descriptive - analytical in terms of method. First, the data were collected using questionnaire tools for indexing and then Shannon entropy method was used to weight social exclusion indices. The target neighborhoods are then ranked and leveled based on the Coopers model and analyzed spatially through a map in ArcGIS. Results:According to the indicators of social exclusion from a total of 13 neighborhoods, the residents of 4 neighborhoods, all of which are located in the northern part of the region, do not suffer from social exclusion due to their social context, economic situation and access to political power structure. While the neighborhoods of Bazaar, Imamzadeh Yahya, Sangalaj and Harandi, which have the largest population and area and form the old and central core of Tehran, are severely socially excluded in terms of socio-cultural, economic- structural and political-civil dimensions. And the other 5 neighborhoods are in a moderate situation in terms of social exclusion. Conclusion: A study and recognition of the concept and indicators of social exclusion and their evaluation in the urban space of District 12 of Tehran Municipality shows that although this area is located in the heart of Tehran in terms of geographical location, But it is not possible to provide social, political and economic opportunities for all its inhabitantsAnd some of its neighborhoods are considered isolated spacesAnd some neighborhoods are considered excluded spaces.