Groundwater is an important source of water, especially in semi-arid areas. The assessment of the chemical characteristics of groundwater under different land use types the associated risk to human ...health is of important significance for water resources utilization and protecting the ecological environment. The present study analyzed the hydrochemical characteristics and ion sources of groundwater, taking Shuangliao City as an example. The analysis was based on the field investigation (82 water samples), descriptive statistics, correlation analysis, ion proportionality coefficient method, and principal component analysis (PCA). The results indicated that the concentrations of most ions in the aquifer had wide spatiotemporal variation and were susceptible to environmental influences. NO3− showed the highest spatial variability, with concentrations ranging from 0.0 to 529.48 mg·L−1. The processes contributing the most to the chemical composition of groundwater were leaching/dissolution and cation exchange. The spatial distribution of groundwater chemistry types was visually obtained through the combined use of Piper trilinear charts and a Digital Terrain Model (DTM). The HCO3—Ca type dominated. Groundwater Cl−, SO42−, and Ca2+ were negatively correlated with the Normalized Difference Vegetation Index (NDVI) due to the absorption of inorganic salt by vegetation roots, indicating that land use types affect groundwater hydrochemistry in the area. The hazard quotient (HQ) used in the human health risk assessment (HHRA) model indicated children (0.0010–6.4162) to be at the highest risk, followed by adult females (0.0007–4.0396), with adult males (0.0005–3.0863) under the lowest risk. The spatial distribution of groundwater nitrate was shown to pose risks to children, adult females, and adult males across 62.97%, 50.01%, and 39.34% of the study area, respectively. This study can improve the understanding of groundwater evolution and the relationship between water chemistry and land use types. This study can also guide the development and utilization of groundwater resources and conservation of water quality in semi-arid areas.
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•The spatial distribution of groundwater chemistry types was visualized.•Land use types affected groundwater chemistry characteristics.•Different ions showed different responses to NDVI.•The non-carcinogenic health risks of nitrate were analyzed for different age groups.•Groundwater NO3− poses a risk to human health.
•Elevating anodizing temperature induces thinner pore walls and breakdown of AAO films.•Introducing organic acid into electrolyte prevent AAO film from breakdown at 30°C.•Lower the electronic current ...and suppress the formation of oxygen bubbles.•Scour effect of O2 on the porous-type and barrier-type AAO layers was alleviated.
Anodic aluminum oxide films, industrially produced by anodizing aluminum alloys under the galvanostatic mode at a relatively low temperature of 20°C (electrolyte bath temperature), present the reliable anticorrosive effect for numerous applications. For fabricating anodic aluminum oxide films with the promising corrosion resistance as well as high growth rate in a wide temperature range, the effect of anodizing temperatures on the structure and growth mechanism of anodic aluminum oxide films was investigated. As the temperature increases up to 30°C, the stress-driven breakdown of porous-type anodic aluminum oxide layers induced by their thinner pore walls was estimated. This phenomenon is interpreted by an increase of electronic current and thus a strong scour effect of O2 bubbles on the porous-type anodic aluminum oxide layers. Moreover, with the addition of composite organic acid into the sulfuric acid-based electrolyte solution, the anions (C6H5O73−,C4H4O62−) that incorporated into the anodic oxide contribute to lowering the electronic current and thus suppressing the formation of oxygen bubbles, resulting in a thicker barrier-type anodic aluminum oxide layer. This is assumed to be responsible for the enhanced corrosion resistance of anodic aluminum oxide films prepared at 30°C with 50 g/L organic acid addition.
Soil-structure interaction (SSI) system is composed of soil and structure that are two materials with quite different damping behaviors and it is regarded as non-classical damping system in ...conventional concept. Based on the analysis of motion state of SSI system, the paper presents the damping characteristic of SSI system via shaking table test. The results of transfer function, acceleration response time histories and equivalent viscous damping ratio and so on indicate that under certain conditions, SSI system shows approximate classical damping characteristic. In practical projects, dynamical analysis of SSI system can be viewed as approximately classical damping system once the synergistic effect of soil is considered.
•The damping characteristics of soil-structure interaction (SSI) system were investigated.•Identification method of SSI damping system was firstly developed.•A collaborative mechanism between soil and structure was observed after small excitation.•The interface of energy transfer soil-structure interaction system was observed to be integral.•SSI system can be viewed as approximately classical damping system.
The recovery of heat and water from low-grade flue gas is of considerable importance for energy conservation and environmental preservation. While the full-open absorption heat pump shows promise as ...a means of achieving heat and water recovery, the lack of research on heat and mass transfer performance of open-type solution evaporation regeneration represents a significant impediment to its design and operation. This paper experimentally investigates the regeneration performance of an open-type spaying tower equipped with ceramic structured packings. Two different regeneration modes are proposed, namely ambient air receiver mode and flue gas receiver mode, to utilize air or low-grade flue gas as a driving source. The impact of different input parameters on the regeneration characteristics, including heat transfer capacity, water removal rate, thermal efficiency, and humidity effectiveness, are demonstrated. The findings indicate that the enhancement of regeneration can be achieved through the increase of solution flow rate, solution temperature, and flue gas flow rate in both regeneration modes. However, high solution concentration and flue gas humidity ratio can weaken water removal rates and reduce thermal efficiency. For the regeneration of CaCl
2
-H
2
O with a concentration of 55%, flue gas around 200°C with a humidity ratio below 44 g/kg can successfully drive the solution regeneration process. When the solution concentration or flue gas humidity ratio continues to rise, additional energy is necessary for regeneration. Furthermore, the coupled heat and mass transfer coefficients are fitted, which can contribute to the design and optimization of the open-type regenerator.
With the rapid development of artificial intelligence and Internet of Things (IoT) technology, increasingly edge devices have entered people’s daily lives. However, due to the limited performance of ...edge devices, complex models can affect the response speed and efficiency of the whole system. Existing research still cannot simultaneously satisfy the demand for accuracy and response speed of edge devices. This paper proposes a lightweight and highly accurate object detection model that uses the Transformer to address edge devices’ limited computational capacity and storage space. Specifically, the proposed model adopts the Swin Transformer for multi-scale feature extraction to achieve better global modeling capability. In addition, we propose the Neck module with path aggregation network (PAN), which is designed with a two-feature pyramid structure capable of combining semantic and localization information in order to improve the operational performance by exploiting the underlying location features. A lightweight detection head is then developed using group convolution, fusing the two localization branches and removes the additional decoupling operation. Finally, we conduct comparative experiments on three datasets: the Retail-cabinet dataset, the Roadsign dataset, and the Pascal VOC dataset. Experimental results show that compared with the baseline model, our model achieves an 11.8% improvement in
mAP
on the Retail-cabinet dataset while reducing
Params
and
FLOPs
by 23.19% and 71.50%, respectively. The proposed model effectively reduces the model’s computational complexity and improves detection performance, thereby possessing high practical value. This code is released on
https://github.com/ydlam/ST-YOLOX
.
There are still many pressing problems in pedestrian detection, such as difficulty in detection due to severe pedestrian occlusion, difficulty in detecting small objects and low detection speed. In ...this paper, we propose A Fast and Efficient Pedestrian Detector with Center and Scale Prediction (FE-CSP). We combine channel attention with spatial attention, replace the traditional convolution with deformable convolution, and embed the backbone network to propose CSANet (Channel and Spatial Attention Network), which efficiently extracts the semantic features of the object, and then propose a feature pyramid network to replace the traditional concatenation to perform multi-scale feature detection, which effectively improves the detection speed. By conducting experiments on CityPersons, our method achieves 10.1%, 13.7% and 47.4%
M
R
-
2
at a speed of 0.21 s/img on the reasonable setting, small setting and heavy setting, respectively. On Caltech, our method achieves 5.2%
M
R
-
2
at a speed of 0.06 s/img on the Reasonable setting, further demonstrating the superiority and generalization ability of the proposed method.
Camera surveillance is widely used in residential areas, highways, schools and other public places. The monitoring and scanning of sudden abnormal events depend on humans. Human anomaly monitoring ...not only consumes a lot of manpower and time but also has a large error in anomaly detection. Video anomaly detection based on AE (Auto-Encoder) is currently the dominant research approach. The model has a highly symmetrical network structure in the encoding and decoding stages. The model is trained by learning standard video sequences, and the anomalous events are later determined in terms of reconstruction error and prediction error. However, in the case of limited computing power, the complex model will greatly reduce the detection efficiency, and unnecessary background information will seriously affect the detection accuracy of the model. This paper uses the AE loaded with dynamic prototype units as the basic model. We introduce an attention mechanism to improve the feature representation ability of the model. Deep separable convolution operation can effectively reduce the number of model parameters and complexity. Finally, we conducted experiments on three publicly available datasets of real scenarios (UCSD Ped1, UCSD Ped2 and CUHK Avenue). The experimental results show that compared with the baseline model, the accuracy of our model improved by 1.9%, 1.4% and 6.6%, respectively, across the three datasets. Compared with many popular models, the validity of our model in anomaly detection is verified.
The fine-scale spatial patterns of trees and their interactions are of paramount importance for controlling the structure and function of forest ecosystems; however, few management techniques can be ...employed to adjust the structural characteristics of uneven-aged mixed forests. This research provides an accurate, efficient, and impersonal comprehensive thinning index (P-index) for selecting candidate harvesting trees; the index was proposed by weighting the commonly used quantitative indices with respect to stand fine-scale structures, competition status, tree vigor, and tree stability. The applications of the proposed P-index in evaluating and simulating the process of thinning operations were examined using four 1-ha mapped plots with different forest types, namely, natural secondary forest, natural pine-broadleaved mixed forest, natural larch-birch mixed forest, and natural oak forest, which were widely distributed across the Heilongjiang Province in Northeast China. The results indicated that the proposed P-index could effectively affect the structural differentiations between different forest types and alternative thinning intensities. The marginal benefits of alternative thinning intensities on the integrated forest structure indicated that removing 10% of the trees from the plots might be the optimal thinning intensity from the perspective of optimizing stand structure, in which the P-index values could be increased by approximately 5%–11% for the four tested plots. The main conclusion from this paper was that the proposed P-index could be used as a quantitative tool to manage uneven-aged mixed forests.
Each great architecture tells a story to make its space meaningful. What the stadium tells matters how the individual interacts with it. The potent influence of narrative in shaping our cognitive ...processing has been revealed and widely used. This influence, however, has not been the focus of researchers in stadium operations. The present study aimed at investigating the influence of the stadium narrative on approach-avoidance responses and the corresponding neural correlates. Participants were presented with a sequence of pictures expressing a story congruent or incongruent with the general profile of the stadium, and were required to make an enter or exit response. Results showed larger amplitudes of N400 for incongruent trials than congruent trials at the end of the narrative, indicating the feasibility of continuity editing procedure for the study of narratives. Moreover, larger amplitudes of LPP were observed in response to the stadium preceded by congruent trials than incongruent trials. This effect was more pronounced in the left than right frontal sites. The LPP suggested that a congruent narrative imparted the stadium approaching affective features, and induced approaching responses, which was consistent with the behavioral and correlational results. Our findings suggested that changes in narrative were sufficient to shape the approach-avoidance responses and the underlying neural correlates. Implications for stadium management and buildings are provided.
This study was conducted to determine the optimum ratio of lysine and methionine (Lys:Met) to enhance milk protein concentration in vitro, focusing on the regulation of genes related to the ...JAK2-STAT5 and the mammalian target of rapamycin (mTOR) signaling pathways. A preliminary dose response study revealed that casein concentration peaked (2.5-2.7 ppm) at a supplemental Lys concentration of 1.2 mM and Met at 0.5 mM. At the peak casein concentration cell proliferation rate also was higher. Furthermore, the expression of CSN1S1, CSN1S2, CSN2, CSN3, LALBA, JAK2, STAT5, and MTOR was upregulated with both Lys and Met compared with the control. A subsequent experiment was conducted as a 5 × 3 factorial design with supplemental Lys plus Met at different ratios. When the supplemental concentration of Lys was 1.2 mM and Met was 0.4 mM (∼3:1), the concentration of casein peaked. Therefore, we measured gene expression, mTOR protein expression, and phosphorylated mTOR (p-mTOR) in cultures incubated with 3:1 Lys:Met (Lys&Met). Expression of CSN1S1 and LALBA were the most highly expressed genes (P < 0.01). The upregulation of CSN2, CSN3, CSN1S2 isoforms (P < 0.01) and JAK2, ELF5, mTOR (P < 0.05) was also observed. Total mTOR protein expression was greater (P < 0.05) with Lys alone and also Lys&Met. However, Lys&Met resulted in the greatest (P < 0.05) p-mTOR. Results suggest that peak concentration of casein at a supplemental 3:1 Lys:Met is driven in part via upregulation of the mRNA expression of components of the JAK-STAT and mTOR pathways.
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