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1.
PLoS One ; 19(1): e0297152, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38241298

RESUMO

The extraction of roadways from remote sensing imagery constitutes a pivotal task, with far-reaching implications across diverse domains such as urban planning, management of transportation systems, emergency response initiatives, and environmental monitoring endeavors. Satellite images captured during daytime have customarily served as the primary resource for this extraction process. However, the emergence of Nighttime Light (NTL) remote sensing data introduces an innovative dimension to this arena. The exploration of NTL data for road extraction remains in its nascent stage, and this study seeks to bridge this gap. We present a refined U-Net model (CA U-Net) integrated with Cross-Attention Mechanisms, meticulously designed to extract roads from Yangwang-1 NTL images. This model incorporates several enhancements, thereby improving its proficiency in identifying and delineating road networks. Through extensive experimentation conducted in the urban landscape of Wenzhou City, the model delivers highly accurate results, achieving an F1 score of 84.46%. These outcomes significantly surpass the performance benchmarks set by Support Vector Machines (SVM) and the Optimal Threshold (OT) method. This promising development paves the way towards maximizing the utility of NTL data for comprehensive mapping and analysis of road networks. Furthermore, the findings underscore the potential of utilizing Yangwang-1 data as a reliable source for road extraction and reaffirm the viability of deploying deep learning frameworks for road extraction tasks utilizing NTL data.


Assuntos
Monitoramento Ambiental , Telemetria , Cidades , China , Monitoramento Ambiental/métodos , Planejamento de Cidades
3.
Nature ; 616(7956): 300-305, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36927804

RESUMO

Achieving food-system sustainability is a multidimensional challenge. In China, a doubling of crop production since 1990 has compromised other dimensions of sustainability1,2. Although the country is promoting various interventions to enhance production efficiency and reduce environmental impacts3, there is little understanding of whether crop switching can achieve more sustainable cropping systems and whether coordinated action is needed to avoid tradeoffs. Here we combine high-resolution data on crop-specific yields, harvested areas, environmental footprints and farmer incomes to first quantify the current state of crop-production sustainability. Under varying levels of inter-ministerial and central coordination, we perform spatial optimizations that redistribute crops to meet a suite of agricultural sustainable development targets. With a siloed approach-in which each government ministry seeks to improve a single sustainability outcome in isolation-crop switching could realize large individual benefits but produce tradeoffs for other dimensions and between regions. In cases of central coordination-in which tradeoffs are prevented-we find marked co-benefits for environmental-impact reductions (blue water (-4.5% to -18.5%), green water (-4.4% to -9.5%), greenhouse gases (GHGs) (-1.7% to -7.7%), fertilizers (-5.2% to -10.9%), pesticides (-4.3% to -10.8%)) and increased farmer incomes (+2.9% to +7.5%). These outcomes of centrally coordinated crop switching can contribute substantially (23-40% across dimensions) towards China's 2030 agricultural sustainable development targets and potentially produce global resource savings. This integrated approach can inform feasible targeted agricultural interventions that achieve sustainability co-benefits across several dimensions.


Assuntos
Produção Agrícola , Meio Ambiente , Fazendeiros , Renda , Desenvolvimento Sustentável , China , Produção Agrícola/economia , Produção Agrícola/métodos , Fertilizantes/análise , Desenvolvimento Sustentável/economia , Desenvolvimento Sustentável/tendências , Praguicidas , Gases de Efeito Estufa
4.
Sci Prog ; 105(3): 368504221118231, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35975589

RESUMO

This paper constructs an Economy-Energy-Emissions (3E) System Dynamics Model using the megacity of Beijing, China, as an example, to estimate the effects of different policy scenarios (including three single-policy scenarios and four combined-policy scenarios) on the core variables of Beijing's 3E system from 2021 to 2035. The results suggest two main points. (1) Following the current development trend, the proportion of the GDP represented by the added value of advanced high-precision industries (Gao Jing Jian in Chinese) will only be 43% in 2035, implying a limited role in promoting economic growth. Despite effective control of total energy consumption, fossil energy's share of total consumption will reach 57% by 2035, hindering the process of making the energy consumption structure cleaner and leading to failure to achieve the targeted inflection point in CO2 emissions by 2025. PM2.5 control shows some successful results and will decrease to 19 µg/m3 in 2035. However, a gap compared to other world-class cities remains. (2) The implementation of a single policy for either industrial structure optimization, energy structure transformation, or emissions control cannot simultaneously meet the goal of high-quality coordinated development of Beijing's 3E system, whereas the comprehensive implementation of policies in all three dimensions is demonstrably effective.


Assuntos
Desenvolvimento Econômico , Indústrias , Pequim , Dióxido de Carbono/análise , China , Cidades
5.
Zhongguo Wei Zhong Bing Ji Jiu Yi Xue ; 21(10): 587-9, 2009 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-19846002

RESUMO

OBJECTIVE: To observe the pathological changes in exfoliated cells from lower respiratory tract mucosa in patients undergoing mechanical ventilation for various duration. METHODS: The secretion of lower respiratory tract was collected in 144 patients of cerebral vascular diseases undergoing invasive mechanical ventilation, and exfoliated cells were examined under microscope at different time points. According to specimen collection time they were divided into five groups: less than 8 hours (28 cases), 8-24 hours (46 cases), 24 hours-3 days (22 cases), 3-7 days (20 cases), 7-28 days (14 cases), and over 28 days (14 cases). Then the injury to airway mucosa at different time of mechanical ventilation was determined. RESULTS: The mucosal injury of trachea and bronchial was worsened gradually with the prolongation of mechanical ventilation. Airway mucosa structure of less than 8-hour of mechanical ventilation was generally normal, while most cells after 8-24 hours and 24 hours-3 days of ventilation showed mild injury, and most cells from tracheal and bronchial mucosa showed severe injury after 3-7 days, 7-28 days and over 28 days of ventilation. Except the difference was not statistically significant between 7-28 days and over 28 days group (P>0.05), the differences between remaining groups were statistically significant (all P<0.05). The correlated coefficient between the duration of mechanical ventilation and airway mucosal injury was 0.781 (P<0.05), and the difference was statistically significant. CONCLUSION: There are linear correlation between length of mechanical ventilation and the airway mucosal cell injury; injuries emerges when the mechanical ventilation time exceeds 8 hours with the prolongation mechanical ventilation time, there is severe damage of airway mucosa when mechanical ventilation lasted more than 7 days, but there is no difference in extent of injury after 7 days.


Assuntos
Mucosa/patologia , Respiração Artificial/efeitos adversos , Traqueia/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Tempo , Adulto Jovem
6.
Artigo em Inglês | MEDLINE | ID: mdl-19268627

RESUMO

A novel (3,4-disfluoro)phenylquione (2F-PQ) was synthesized through the reaction of 3,4-Difluoroaniline and 1,4-benzoquinone. Its structure was verified by (1)H NMR, FTIR and Raman spectra. The ground-state geometries were optimized by using density functional theory (DFT) at B3LYP/6-311G+(d,p), B3PW91/6-311G+(d,p) and MPB3PW91/6-311G+(d,p) level without symmetry constrains, respectively. The predicted FTIR and Raman spectra scaled by factor are well consistent with experimental spectra.


Assuntos
Benzoquinonas/síntese química , Vibração , Benzoquinonas/química , Modelos Moleculares , Conformação Molecular , Espectrofotometria Infravermelho , Análise Espectral Raman
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