An Integration Method for Regional PM2.5 Pollution Control Optimization Based on Meta-Analysis and Systematic Review

PM2.5 pollution in China is becoming increasingly severe, threatening public health. The major goal of this study is to evaluate the mortality rate attributed to PM2.5 pollution and design pollution mitigation schemes in a southern district of China through a two-objective optimization model. The mortality rate is estimated by health effect evaluation model. Subjected to limited data information, it is assumed that the meta-analysis method, through summarizing and combining the research results on the same subject, was suitable to estimate the percentage of deaths caused by PM2.5 pollution. The critical parameters, such as the total number of deaths and the background concentration of PM2.5, were obtained through on-site survey, data collection, literature search, policy analysis, and expert consultation. The equations for estimating the number of deaths caused by PM2.5 pollution were established by incorporating the relationship coefficient of exposure to reaction, calculated residual PM2.5 concentration of affected region, and statistical total base number of deaths into a general framework. To balance the cost from air quality improvement and human health risks, a two-objective optimization model was developed. The first objective is to minimize the mortality rate attributable to PM2.5 pollution, and the second objective is to minimize the total system cost over three periods. The optimization results demonstrated that the combination of weights assigned to the two objectives significantly influenced the model output. For example, a high weight value assigned to minimizing the number of deaths results in the increased use of treatment techniques with higher efficiencies and a dramatic decrease in pollutant concentrations. In contrast, a model weighted more toward minimizing economic loss may lead to an increase in the death toll due to exposure to higher air pollution levels. The effective application of this model in the Nanshan District of Shenzhen City, China, is expected to serve as a basis for similar work in other parts of the world in the future.

Composition of binary quadratic forms over number fields

In this article, the standard correspondence between the ideal class group of a quadratic number field and the equivalence classes of binary quadratic forms of given discriminant is generalized to any base number field of narrow class number one. The article contains an explicit description of the correspondence. In the case of totally negative discriminants, equivalent conditions are given for a binary quadratic form to be totally positive definite.

Rapid Fleet Condition Analysis through Correlating Basic Vehicle Tracking Data with Engine Oil FT-IR Spectra

Engine oil condition and tribological performance are strongly interrelated. Accordingly, oil condition monitoring is common in various applications. This is especially important, as oil condition depends on the fueling and utilization profile of an internal combustion engine. Common practice involves the measurement of various parameters, such as the total acid number and total base number, oxidation, nitration, viscosity, and elemental composition; thus, it can be time-consuming and resource-intensive. This study provides a methodology for rapid analysis for large vehicle fleets or sample sizes, using only Fourier-transformed infrared spectroscopy and the subsequent multivariate data analysis offers a rapid alternative to commonly available methods. The described method provides a rapid, cost-efficient, and intuitive approach to uncovering differences in the oil condition. Furthermore, understanding the underlying reasons in engine construction and the resulting chemical degradation is also possible.

Recovery strategy of multilayer network against cascading failure

Cascading failure phenomena widely exist in real-life circumstances, such as the blackouts in power networks and the collapse in computer networks. In this paper, we construct a cascading failure model on the multilayer network, taking into account the number of invalid neighbors of nodes, the failure frequency of nodes, the effect between layers, and the percolation process. To minimize network losses caused by the cascading process, we propose a recovery strategy, i.e. repairing some certain clusters formed by ineffective nodes and links. The recovery strategy is discussed in detail, like whether to add links to the network, how many links are needed at least to add, how many layers are demanded to restore, and how to choose the values of [Formula: see text] and restorable threshold [Formula: see text] to improve the network performance. Besides, we theoretically analyze the cascading failure model with recovery strategy by virtue of mean-field approximation and generating function techniques. The theoretical solutions are found to be consistent with experimental results simulated on the ER as well as BA networks. In addition, we also investigate the affecting factors of network robustness. The effects of failure threshold [Formula: see text], base number [Formula: see text], and threshold [Formula: see text] between layers on network behaviors depend on the values of average degree [Formula: see text] and recovery proportion [Formula: see text]. These results may provide particular reference significance for maintaining system security, adjusting the network performance, and enhancing network robustness.

Descending Dysploidy and Bidirectional Changes in Genome Size Accompanied Crepis (Asteraceae) Evolution

The evolution of the karyotype and genome size was examined in species of Crepis sensu lato. The phylogenetic relationships, inferred from the plastid and nrITS DNA sequences, were used as a framework to infer the patterns of karyotype evolution. Five different base chromosome numbers (x = 3, 4, 5, 6, and 11) were observed. A phylogenetic analysis of the evolution of the chromosome numbers allowed the inference of x = 6 as the ancestral state and the descending dysploidy as the major direction of the chromosome base number evolution. The derived base chromosome numbers (x = 5, 4, and 3) were found to have originated independently and recurrently in the different lineages of the genus. A few independent events of increases in karyotype asymmetry were inferred to have accompanied the karyotype evolution in Crepis. The genome sizes of 33 Crepis species differed seven-fold and the ancestral genome size was reconstructed to be 1 C = 3.44 pg. Both decreases and increases in the genome size were inferred to have occurred within and between the lineages. The data suggest that, in addition to dysploidy, the amplification/elimination of various repetitive DNAs was likely involved in the genome and taxa differentiation in the genus.

The i̇nfluence of water on the change i̇n engi̇ne oi̇l quali̇ty i̇ndi̇cators

Introduction. One of the main types of deposits in an internal combustion engine is an emulsion or sludge formed by water, decomposition of fuel residues and solid residues. The sludge usually settles on the colder surfaces of the engine, such as the bottom of the crankcase pan, valve chambers and upper boards. The main problem is that this type of deposits can be collected by the engine oil and transferred to areas such as the oil pump, intake valve or oil channels, where the sludge can interfere with the flow of oil and cause a failure of the lubrication mode. In addition to the disruption in the operation of the above-mentioned systems, the engine oil quality indicators are also undergoing changes for the worse.Materials and methods. To monitor the condition of the engine oil, it is necessary to determine the characteristics of its performance, such as: kinematic viscosity at 40 oC and at 100 oC, acid number, base number and determine the number of elements – indicators of additives and wear products contained in the engine oil. The viscosity was determined using a Stabinger SVM 3000 viscometer. It measures the dynamic viscosity and density of oils and fuels in accordance with ASTM D7042 and automatically calculates the kinematic viscosity, viscosity index and outputs the measurement results. The acid and base numbers were determined using an automatic titrator TitroLine alpha plus, and the presence of indicator elements in engine oil using an inductively coupled plasma optical emission spectrometer of the iCAP 7000 series, designed for analysis and determination of the number of indicator elements in liquid and solid samples.Results. The dynamics of changes in the performance characteristics of the Gazpromneft Diesel Ultra 10W-40 engine oil with an extended replacement interval, which is applicable for equipment operating in severe conditions, depending on the water content in the samples of this lubricant, was analyzed.Conclusion. The consequences that may occur due to water entering the engine oil are indicated.