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1.
Sci Rep ; 14(1): 12437, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38816559

RESUMO

The min-max multi-vehicle Chinese postman problem is an NP-hard problem, which is widely used in path planning problems based on road network graphs, such as urban road structure probing planning, urban road underground cavity detection planning, high-voltage line inspection planning, and so on. With the rapid increase in the number of nodes and connections of road network graph, the solution time and path equilibrium constraints pose new challenges to the problem solving. In this paper, we propose a critical-edge tabu search algorithm, CTA-kroutes, for solving the min-max multi-vehicle postman problem for large-scale road networks. First, the initial solution with balanced path lengths is obtained by segmenting the Eulerian paths; second, the critical edges are moved in the initial solution to construct the neighborhood solution, and the tabu search algorithm is used to find the optimal solution iteratively; and lastly, the solution optimization algorithm is used at the end of each iteration to de-duplicate and optimally reconstruct the current search result. Experiments show that the CTA-kroutes algorithm can effectively improve the equalization of multi-vehicle paths and its applicability to large-scale road networks.

2.
Digit Health ; 9: 20552076231185441, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37426583

RESUMO

Objectives: This study is designed to analyze the potential influencing factors of hyperlipidemia, and to explore the relationship between liver function indicators such as gamma-glutamyltransferase (GGT) and hyperlipidemia. Methods: Data were derived from 7599 outpatients who visited the Department of Endocrinology of the First Hospital of Jilin University (2017-2019). A multinomial regression model is used to identify related factors of hyperlipidemia and the decision tree method is used to explore the general rules in hyperlipidemia patients and non-hyperlipidemia patients on these factors. Results: The average of age, body mass index (BMI), systolic blood pressure (SBP), diastolic blood pressure, aspartate aminotransferase, alanine aminotransferase (ALT), GGT and glycosylated hemoglobin (HbA1c) in the hyperlipidemia group are higher than those in the non-hyperlipidemia group. In multiple regression analysis, SBP, BMI, fasting plasma glucose, 2-h postprandial blood glucose, HbA1c, ALT, GGT are associated with triglyceride. For people with HbA1c less than 6.0%, controlling GGT within 30 IU/L reduces the prevalence of hypertriglyceridemia by 4%, and for people with metabolic syndrome with impaired glucose tolerance controlling GGT within 20 IU/L reduces the prevalence of hypertriglyceridemia by 11%. Conclusions: Even when GGT is in the normal range, the prevalence of hypertriglyceridemia increases with its gradual increase. Controlling GGT in people with normoglycemia and impaired glucose tolerance can reduce the risk of hyperlipidemia.

3.
Environ Sci Pollut Res Int ; 28(21): 26948-26960, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33496950

RESUMO

Cities are usually the final destination for consumable goods and services produced along supply chains and the most appropriate scale to implement policy. Consumption-based policies could complement current carbon emissions mitigation actions, but such studies at the city level are relatively rare. We used a demand-driven input-output model to explore a historical time series (1987-2012) of consumption-based emissions in Tianjin for the first time, a typical industrial city which has the largest carbon footprint in China. The results reveal the differences between consumption- and production-based emissions, and Tianjin has transformed from a producer city into a typical consumer city since 2000s, mainly due to infrastructure construction. There is more capital investment in industrial infrastructures than in real estate in Tianjin, causing the largest carbon footprint. The trade deficit and different carbon intensity have substantial influences on consumption-based emissions. Finally, population, income, and urbanization could enable a more accurate interpretation of urban carbon footprint growth. Demand-driven policy implications for addressing these emissions in booming industrial cities are discussed and provide a new perspective on carbon emissions mitigation. Our results offer valuable lessons on industrial cities' strategies and initiatives for climate change mitigation worldwide, particularly in developing countries.


Assuntos
Pegada de Carbono , Carbono , China , Cidades , Indústrias
4.
Environ Sci Technol ; 48(5): 2541-50, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24483209

RESUMO

Achievement of carbon emission reduction targets proposed by national governments relies on provincial/state allocations. In this study, a hybrid method for provincial energy-related carbon emissions allocation in China was developed to provide a good balance between production- and consumption-based approaches. In this method, provincial energy-related carbon emissions are decomposed into direct emissions of local activities other than thermal power generation and indirect emissions as a result of electricity consumption. Based on the carbon reduction efficiency principle, the responsibility for embodied emissions of provincial product transactions is assigned entirely to the production area. The responsibility for carbon generation during the production of thermal power is borne by the electricity consumption area, which ensures that different regions with resource endowments have rational development space. Empirical studies were conducted to examine the hybrid method and three indices, per capita GDP, resource endowment index and the proportion of energy-intensive industries, were screened to preliminarily interpret the differences among China's regional carbon emissions. Uncertainty analysis and a discussion of this method are also provided herein.


Assuntos
Poluição do Ar/prevenção & controle , Sequestro de Carbono , Carbono/análise , Conservação dos Recursos Naturais/métodos , Fontes de Energia Elétrica , Centrais Elétricas , Poluição do Ar/economia , Dióxido de Carbono/análise , China , Mudança Climática , Conservação dos Recursos Naturais/economia , Indústrias , Modelos Teóricos , Incerteza , Urbanização
5.
Surg Neurol ; 72 Suppl 1: S17-20, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18514265

RESUMO

BACKGROUND: Fibrous dysplasia of the skull is difficult to manage when the cranial nerves, skull base, and face are involved. The procedure for the surgical treatment of this lesion needs to be studied clinically because of the low incidence rate and its operative complicacy. Faced with this, combined with our clinical experience, we explore the surgical strategy and operative procedures of the skull fibrous dysplasia. METHODS: Twelve patients with skull fibrous dysplasia have been studied with neuroimaging and underwent operative removal of the lesion and cranioplasty and/or reestablishment of the skull base. RESULTS: Excellent operating outcome was obtained in 9 cases and good in 3 based on the evaluation of the lesion removal, cranioplasty, skull base reestablishment, and cranial nerve function recovery. CONCLUSION: Surgical treatment is suitable for a patient whose lesion damages his or her cranial nerve function and/or appearance. In general, removal of the lesion, cranioplasty, and/or skull base reestablishment can be finished in 1 stage.


Assuntos
Descompressão Cirúrgica , Displasia Fibrosa Óssea/cirurgia , Procedimentos Neurocirúrgicos/métodos , Nervo Óptico/cirurgia , Crânio/patologia , Crânio/cirurgia , Adolescente , Adulto , Craniotomia/métodos , Descompressão Cirúrgica/métodos , Ossos Faciais/patologia , Ossos Faciais/cirurgia , Feminino , Displasia Fibrosa Óssea/complicações , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Seios Paranasais/cirurgia , Resultado do Tratamento , Adulto Jovem
6.
J Phys Chem A ; 109(10): 2364-72, 2005 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-16839007

RESUMO

The structures, energetics, spectroscopies, and stabilities of the doublet NC(2)O radical are explored at density functional theory and ab initio levels. Nine minimum isomers are located connected by 22 interconversion transition states. At the CCSD(T)/6-311+G(2df)//QCISD/6-311G(d)+ZPVE level, the lowest-lying isomer is bent NCCO 1 (0.0 kcal/mol) with (2)A' state followed by bent isomer CNCO 2 (16.7). Two isomers (1 and 2) and another high-lying species CCNO 4 (99.4) with bent structure are considerably stabilized by a barrier of at least 20 kcal/mol. All of the three isomers should be experimentally or astrophysically observable. This result is consistent with their indication of neutralization-reionization mass spectrometry experiments. Also, the calculated spectroscopic properties and bond distances of known NCCO 1 are consistent with recent experimental observations and theoretical studies. The bonding natures of the isomers 1, 2, and 4 are analyzed. Their molecular properties including the heats of formation, adiabatic ionization potentials, and adiabatic electronic affinities are calculated at the higher levels G3//B3LYP, G3(MP2)//B3LYP, QCISD, and CCSD(T) (single-point). Possible formation strategies of the isomers 1, 2, and 4 in laboratory and space are also discussed in detail.

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