BACKGROUND:Heatstroke has become a common emergency event in hospitals.Procalcitonin(PCT)is used as a biomarker of infection in the emergency department(ED),but its role in rhabdomyolysis(RM)following exertional heats...BACKGROUND:Heatstroke has become a common emergency event in hospitals.Procalcitonin(PCT)is used as a biomarker of infection in the emergency department(ED),but its role in rhabdomyolysis(RM)following exertional heatstroke(EHS)remains unclear.METHODS:A retrospective cohort study enrolled patients with EHS from the intensive care unit(ICU).We collected RM biomarkers,inflammation markers,critical disease scores at admission,24 h,48 h,and discharge,and 90-day mortality.Correlation analysis,linear regression and curve fi tting were used to identify the relationship between PCT and RM.RESULTS:A total of 162 patients were recruited and divided into RM(n=56)and non-RM(n=106)groups.PCT was positively correlated with myoglobin(Mb),acute hepatic injury,disseminated intravascular coagulation(DIC),Sequential Organ Failure Assessment(SOFA)score,and Acute Physiology and Chronic Health Evaluation II(APACHE II)score,with correlation coefficients of 0.214,0.237,0.285,0.454,and 0.368,respectively(all P<0.05).Interestingly,the results of curve fi tting revealed a nonlinear relationship between PCT and RM,and a two-piecewise linear regression model showed that PCT was related to RM with an odds ratio of 1.3 and a cut-off of<4.6 ng/mL.Survival analysis revealed that RM was associated with higher mortality compared to non-RM cases(P=0.0093).CONCLUSION:High serum PCT concentrations are associated with RM after EHS in critically ill patients.Elevated PCT concentrations should be interpreted cautiously in patients with EHS in the ED.展开更多
Threaded fasteners are one of the most commonly used connection methods for mechanical structures.Its primary function is to generate appropriate clamping forces and fasten the connected parts.An inappropriate preload...Threaded fasteners are one of the most commonly used connection methods for mechanical structures.Its primary function is to generate appropriate clamping forces and fasten the connected parts.An inappropriate preload can cause loosening,fatigue fracture,and other problems.This will affect the safety and reliability of mechanical equipment.The precise control of the preload has become a critical issue in mechanical assembly processes.Over the past few decades,various tightening measures and methods have been proposed to address this issue.However,many problems continue to exist with practical applications that have not been reviewed comprehensively and systematically.First,various control methods were summarized systematically,and their advantages and disadvantages in engineering applications were analyzed.Torque control is the most widely used tightening method owing to its simple operation and low cost.Therefore,the research on the torque control method was summarized systematically from three aspects:the torque-preload correlation formula,effective friction radius,and friction characteristics during tightening.In addition,the special circumstances that may increase preload uncertainty were discussed.Finally,based on a summary of the current research status,the prospects for future research were discussed.This study would aid researchers in extensively understanding the problems in preload control.展开更多
The precise measurement of Al, Mg, Ca, and Zn composition in copper slag is crucial for effective process control of copper pyrometallurgy. In this study, a remote laser-induced breakdown spectroscopy(LIBS) system was...The precise measurement of Al, Mg, Ca, and Zn composition in copper slag is crucial for effective process control of copper pyrometallurgy. In this study, a remote laser-induced breakdown spectroscopy(LIBS) system was utilized for the spectral analysis of copper slag samples at a distance of 2.5 m. The composition of copper slag was then analyzed using both the calibration curve(CC) method and the partial least squares regression(PLSR) analysis method based on the characteristic spectral intensity ratio. The performance of the two analysis methods was gauged through the determination coefficient(R^(2)), average relative error(ARE), root mean square error of calibration(RMSEC), and root mean square error of prediction(RMSEP). The results demonstrate that the PLSR method significantly improved both R^(2) for the calibration and test sets while reducing ARE, RMSEC, and RMSEP by 50% compared to the CC method. The results suggest that the combination of LIBS and PLSR is a viable approach for effectively detecting the elemental concentration in copper slag and holds potential for online detection of the elemental composition of high-temperature molten copper slag.展开更多
Accurate short-termphotovoltaic(PV)power prediction helps to improve the economic efficiency of power stations and is of great significance to the arrangement of grid scheduling plans.In order to improve the accuracy ...Accurate short-termphotovoltaic(PV)power prediction helps to improve the economic efficiency of power stations and is of great significance to the arrangement of grid scheduling plans.In order to improve the accuracy of PV power prediction further,this paper proposes a data cleaning method combining density clustering and support vector machine.It constructs a short-termPVpower predictionmodel based on particle swarmoptimization(PSO)optimized Long Short-Term Memory(LSTM)network.Firstly,the input features are determined using Pearson’s correlation coefficient.The feature information is clustered using density-based spatial clustering of applications withnoise(DBSCAN),and then,the data in each cluster is cleanedusing support vectormachines(SVM).Secondly,the PSO is used to optimize the hyperparameters of the LSTM network to obtain the optimal network structure.Finally,different power prediction models are established,and the PV power generation prediction results are obtained.The results show that the data methods used are effective and that the PSO-LSTM power prediction model based on DBSCAN-SVM data cleaning outperforms existing typical methods,especially under non-sunny days,and that the model effectively improves the accuracy of short-term PV power prediction.展开更多
<div style="text-align:justify;"> Bearings are widely utilized as key components in industrial scenarios. Therefore, the automatic and precise inspection of bearing defects is imperative for the manufa...<div style="text-align:justify;"> Bearings are widely utilized as key components in industrial scenarios. Therefore, the automatic and precise inspection of bearing defects is imperative for the manufacturing of the bearing. In this paper, a novel defect detection method based on acoustics is proposed to further improve both the accuracy and the efficiency of the defection process. We firstly constructed a labeled dataset composed of acoustic signals sampling from different bearings with a certain rotational speed. OpenSMILE is adopted to extract the acoustic features and the target acoustic feature dataset with 6373 features is formed. To further improve the efficiency of the proposed method, a feature selection strategy based on the chi-square test is adopted to eliminate the most inefficient features. Several statistical learning models are constructed and trained as the classifier. Eventually, the performance of classifiers is evaluated and achieves relatively high accuracy and efficiency with an extremely imbalanced dataset. </div>展开更多
In the sorting system of the production line,the object movement,fixed angle of view,light intensity and other reasons lead to obscure blurred images.It results in bar code recognition rate being low and real time bei...In the sorting system of the production line,the object movement,fixed angle of view,light intensity and other reasons lead to obscure blurred images.It results in bar code recognition rate being low and real time being poor.Aiming at the above problems,a progressive bar code compressed recognition algorithm is proposed.First,assuming that the source image is not tilted,use the direct recognition method to quickly identify the compressed source image.Failure indicates that the compression ratio is improper or the image is skewed.Then,the source image is enhanced to identify the source image directly.Finally,the inclination of the compressed image is detected by the barcode region recognition method and the source image is corrected to locate the barcode information in the barcode region recognition image.The results of multitype image experiments show that the proposed method is improved by 5+times computational efficiency compared with the former methods,and can recognize fuzzy images better.展开更多
Designing low-cost and high-performance photoelectrodes with improved light harvesting and charge separation rates is significant in photoelectrochemical water splitting.Here,a novel TiO2/Cu2O/Al/Al2O3 photoelectrode ...Designing low-cost and high-performance photoelectrodes with improved light harvesting and charge separation rates is significant in photoelectrochemical water splitting.Here,a novel TiO2/Cu2O/Al/Al2O3 photoelectrode is manufactured by depositing plasmonic nanoparticles of the non-noble metal Al on the surface of a TiO2/Cu2O core/shell heterojunction for the first time.The Al nanoparticles,which exhibit a surface plasmon resonance(SPR)effect and are substantially less expensive than noble metals such as Au and Ag,generate hot electron-hole pairs and amplify the electromagnetic field at the interface under illumination.The as-prepared TiO2/Cu2O/Al/Al2O3 photoelectrodes have an extended absorption range and enhanced carrier separation and transfer.Their photocurrent density of 4.52 mA·cm^-2 at 1.23 V vs.RHE represents an 1.84-fold improvement over that of TiO2/Cu2O.Specifically,the ultrathin Al2O3 passivation layer spontaneously generated on the surface of Al in air could act as a protective layer to significantly increase its stability.In this work,the synergistic effect of the heterojunctions and the SPR effect of the non-noble metal Al significantly improve the photoelectrode performance,providing a novel concept for the design of electrodes with good properties and high practicability.展开更多
Highly efficient sheet-like BiPO4/zeolite and ball-flower-like BiPO4/zeolite had been successfully synthesized by a standard hydrothermal method. The addition of assistant reagent in the hydrothermal system is promisi...Highly efficient sheet-like BiPO4/zeolite and ball-flower-like BiPO4/zeolite had been successfully synthesized by a standard hydrothermal method. The addition of assistant reagent in the hydrothermal system is promising to obtain special morphology. The assistant reagent (EDTA) acts as a growth modifier of crystal. The possible formation mechanisms of sheet-like BiPO4/zeolite and ball-flower-like BiPO4/zeolite were schematically discussed. A detailed study of sheet-like BiPO4/zeolite and ball-flower-like BiPO4/zeolite impacted on the photodecoloration methylene blue (MB) solution showed that the composite had a highly reusable and stable property for long-run photocatalytic application. (C) 2016 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. and Science Press. All rights reserved.展开更多
The Tibetan Plateau(TP)is undergoing rapid urbanization.To improve urban sustainability and construct eco-logical security barriers,it is essential to quantify the spatial patterns of urbanization level on the TP,but ...The Tibetan Plateau(TP)is undergoing rapid urbanization.To improve urban sustainability and construct eco-logical security barriers,it is essential to quantify the spatial patterns of urbanization level on the TP,but the existing studies on the topic have been limited by the lack of socioeconomic data.This study aims to quantify the urbanization level on the TP in 2018 with Luojia1-01(LJ1-01)high-resolution nighttime light(NTL)data.Specifically,the compounded night light index is used to quantify spatial patterns of urbanization level at mul-tiple scales.The results showed that the TP had a low overall urbanization level with a large internal difference.The urbanization level in the northeast,southeast and south of the TP was relatively high,forming three hotspots centered in Xining City,Lhasa City and Shangri-La City,while the urbanization level in the central and western regions was relatively low.The analysis of influencing factors,based on the random forest model,showed that transportation and topography were the main factors affecting the TP’s spatial patterns of urbanization level.The comparison analysis with socioeconomic statistics and traditional NTL data showed that LJ1-01 NTL data can be used to more effectively quantify the urbanization level since it is more advantageous for reflecting the spatial extent of urban land and describing the spatial structure of socioeconomic activities within urban areas.These advantages are attributed to the high spatial resolution of the data,appropriate imaging time and unaf-fected by saturation phenomena.Thus,the proposed LJ1-01 NTL-based urbanization level measurement method has the potential for wide applications around the world,especially in less-developed regions lacking statistical data.Using this method,we refined the measurement of the TP’s urbanization level in 2018 for multiple scales including the region,basin,prefecture and county levels,which provides basic information for the further urban sustainability research on the TP.展开更多
Through the analysis of the faults and their internal structure in Zhu I Depression,it is found that the internal structure of the late fault is obviously segmented vertically.It develops unitary structure(simple faul...Through the analysis of the faults and their internal structure in Zhu I Depression,it is found that the internal structure of the late fault is obviously segmented vertically.It develops unitary structure(simple fault plane)in shallow layers,binary structure(induced fracture zone in hanging wall and sliding fracture zone in footwall)in middle,layers and ternary structure(induced fracture zone in hanging wall and sliding fracture zone in middle,and induced fracture zone in footwall)in deep layers.Because the induced fracture zone is a high porosity and permeability zone,and the sliding fracture zone is a low porosity and ultra-low permeability zone,the late fault in middle layers has the character of"transporting while sealing".The late fault can transport hydrocarbon by its induced fracture zone in the side of the hanging wall and seal hydrocarbon by its sliding fracture zone in the side of the footwall.In deep layers,the late fault has the character of"dual-transportation",induced fracture zones in both sides of hanging wall and footwall can transport hydrocarbon.The early fault that only developed in the deep layers is presumed to be unitary structure,which plays a completely sealing role in the process of hydrocarbon migration and accumulation due to inactivity during the hydrocarbon filling period.Controlled by hydrocarbon source,early/late faults,sand bodies and traps,two reservoir-forming models of"inverted L"and"stereo-spiral"can be proposed in middle layers,while two reservoir-forming models of"cross fault"and"lateral fault sealing"are developed in the deep layers of Zhu I Depression.展开更多
The highly ordered TiO2 nanotubes (NTs) were fabricated by the anodic oxidation method. Their morphology, structure and crystalline phase were characterized by scanning electron microscopy (SEM) and X-ray diffractomet...The highly ordered TiO2 nanotubes (NTs) were fabricated by the anodic oxidation method. Their morphology, structure and crystalline phase were characterized by scanning electron microscopy (SEM) and X-ray diffractometer (XRD). The effects of morphology, specific surface area, pore structures and photo catalytic activity of the TiO2 NTs were investigated. UV-vis spectra analysis showed that its light absorption had been extended to the visible light range. The photocatalytic activity of the as-prepared samples was evaluated by photocatalytic oxidation of gaseous HCHO and MB aqueous solution. The samples had better adhesion strength in the dark and showed a higher photocatalytic activity than nanoparticles. Especially, with ultraviolet light pretreatment, the nanotubes exhibited more stable active for photocatalytic decomposition and the photodecomposition rate remained at high level after 3 cycles of the photocatalysis experiment. Thus, how the number of surface active group center dot OH increased and the mechanism for the great improvement for the photocatalytic activity are discussed. (C) 2016 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. and Science Press. All rights reserved.展开更多
This paper investigates the impact of economic policy uncertainty(EPU)on the crash risk of US stock market during the COVID-19 pandemic.To this end,we use the GARCHS(GARCH with skewness)model to estimate daily skewnes...This paper investigates the impact of economic policy uncertainty(EPU)on the crash risk of US stock market during the COVID-19 pandemic.To this end,we use the GARCHS(GARCH with skewness)model to estimate daily skewness as a proxy for the stock market crash risk.The empirical results show the significantly negative correlation between EPU and stock market crash risk,indicating the aggravation of EPU increase the crash risk.Moreover,the negative correlation gets stronger after the global COVID-19 outbreak,which shows the crash risk of the US stock market will be more affected by EPU during the epidemic.展开更多
External therapy,which has been used for millennia to treat disease,has now become the newest member of complementary and alternative therapies.A growing number of clinical studies and animal experiments have shown th...External therapy,which has been used for millennia to treat disease,has now become the newest member of complementary and alternative therapies.A growing number of clinical studies and animal experiments have shown that external therapy exerts a positive effect on the intestinal flora.In this paper,we review the research related to external therapy on various systemic diseases and focus on changes in the intestinal flora.We found that studies on external therapy are dominated by acupuncture and tuina,primarily aimed at the treatment of digestive and neurological diseases.However,the deeper mechanism of regulation of the intestinal flora by external therapy has not yet been experimentally confirmed.展开更多
Objective: To investigate the changes in the hypothalamic metabolites of lipopolysaccharide(LPS) febrile young rabbits after the treatment with pediatric tuina.Methods: A total of 30 young rabbits were randomly assign...Objective: To investigate the changes in the hypothalamic metabolites of lipopolysaccharide(LPS) febrile young rabbits after the treatment with pediatric tuina.Methods: A total of 30 young rabbits were randomly assigned into three groups: the normal group, the model group, and the tuina group. Both the model group and the tuina group were injected intravenously with LPS. “Six antipyretic manipulations”(pushing Tianmen, pushing Kangong, kneading Taiyang,kneading Erhougaogu, clearing Tianheshui, and pushing Jizhu) were administered 1 h after the LPS injection in the tuina group. The rectal temperatures of the young rabbits were monitored during the experiment to explore the antipyretic effect. Three hours after the injection, the content of interleukin-1β(IL-1β), tumor necrosis factor(TNF)-a, and prostaglandin E;(PGE;) in the serum was detected. In addition, liquid chromatography-mass spectrometry(LC-MS) was used for the hypothalamus metabolomics.Results: Compared with the model group, the rectal temperature of the tuina group was decreased at 2 h and 3 h after the LPS injection(P =.04, P =.03, respectively), and the content of IL-1β, TNF-a, and PGE2was decreased(P =.03, P =.003, and P =.008, respectively). The metabolomics results showed that there were 23 potential biomarkers after the tuina intervention, enriching 27 pathways. Lipid metabolites,especially glycerophospholipids, were a majority of the altered metabolites. The primary metabolic pathways affected by tuina included the arachidonic acid metabolism, the GABAergic synapse, D-glutamine and D-glutamate metabolism, and the glutamatergic synapse.Conclusion: Pediatric tuina reduced the temperature of the febrile rabbits and downregulated the expression of IL-1β, TNF-a, and PGE2, and the antipyretic mechanism may be related to changes in metabolites and metabolic pathways in the hypothalamus.展开更多
We report on a novel g-C3N4/TiO 2/Co-Pi photoanode combining a TiO2 protection layer, Co-Pi hole capture layer, and g-C3 N4 light-absorption layer layer for photoelectrochemical(PEC) water splitting to generate hydr...We report on a novel g-C3N4/TiO 2/Co-Pi photoanode combining a TiO2 protection layer, Co-Pi hole capture layer, and g-C3 N4 light-absorption layer layer for photoelectrochemical(PEC) water splitting to generate hydrogen for the first time. This new photoanode with three function layers exhibits enhanced PEC performance with a photocurrent density of 0.346 mA ·cm–2 at 1.1 V(vs. RHE),which is approximately 3.6 times that of pure g-C3N4 photoanode. The enhanced PEC performance of g-C3N4/TiO 2/Co-Pi photoanode benefits from the following:(1) excellent visible light absorption of g-C3N4;(2) stable protection of TiO2 to improve the durability of g-C3N4 film; and(3) photogenerated holes capture Co-Pi to separate photogenerated electron-hole pairs efficiently. This promising multifarious function layers structure provides a new perspective for PEC water splitting to generate hydrogen.展开更多
The aim of this study was to evaluate the genetic parameters of the growth performance of Takifugu rubripes.Heritabilities and genetic correlations were estimated for body weight(BW),body length(BL),total length(TL),c...The aim of this study was to evaluate the genetic parameters of the growth performance of Takifugu rubripes.Heritabilities and genetic correlations were estimated for body weight(BW),body length(BL),total length(TL),chest measurement(CM)and trunk length(TKL)of T.rubripes from measurements of progeny at 6 months and 12 months.The results showed that the heritability was 0.37 for BW6,0.19 for BL6,0.35 for TL6,0.29 for CM6,0.26 for TKL6,0.36 for BW12,0.26 for BL12,0.25 for TL12,0.31 for CM12 and 0.15 for TKL12.The range of genetic correlations estimated at 6 months was 0.025–0.725 and−0.002–0.706 at 12 months.The results indicated that genetic improvement for faster growth rate or increased body weight in cultured T.rubripes was effective.Based on selection theory,the selection strategy for traits with medium heritability is flexible.Considering that these growth traits do not reach the high level of heritability,family selection should be expected.Given positive genetic correlations among BW,BL,TL,CM,and TKL at 6 months,the five traits could be improved simultaneously through selective breeding.As there was high genetic correlation only between BW12,BL12 and TL12,and negative correlations between TKL12 and BL12 as well as between CM12 and TL12,and only BW,BL and TL at 12 months could be improved simultaneously.展开更多
When using shape memory materials into active disassembly of actual electronic products, because the elastic modulus of shape memory materials is affected by the temperature is relatively large, therefore, the main di...When using shape memory materials into active disassembly of actual electronic products, because the elastic modulus of shape memory materials is affected by the temperature is relatively large, therefore, the main difference of environmental reliability between active disassembly products and common products is the impact of collision and vibration under different temperature. Establishing three-dimensional analysis model, comparing the impact of collision and vibration of mobile phone shells which are made up of PVC materials after casting & radiation and PC/ABS materials under different temperature. Analyzing the reliability of mobile phone under different temperature and optimizing its structure according to data of testing.展开更多
There are two difficult in the existing image restoration methods.One is that the method is difficult to repair the image with a large damaged,the other is the result of image completion is not good and the speed is s...There are two difficult in the existing image restoration methods.One is that the method is difficult to repair the image with a large damaged,the other is the result of image completion is not good and the speed is slow.With the development and application of deep learning,the image repair algorithm based on generative adversarial networks can repair images by simulating the distribution of data.In the process of image completion,the first step is trained the generator to simulate data distribution and generate samples.Then a large number of falsified images are quickly generated using the generative adversarial network and search for the code of the closest damaged image.Finally,the generator generates missing content by using this code.On this basis,this paper combines the semantic loss function and the perceptual loss function.Experimental result show that the method successfully predicts the information of large areas missing in the image,and realizes the photorealism,producing clearer and more consistent results than previous methods.展开更多
Image conversion refers to converting an image from one style to another and ensuring that the content of the image remains unchanged.Using Generative Adversarial Networks(GAN)for image conversion can achieve good res...Image conversion refers to converting an image from one style to another and ensuring that the content of the image remains unchanged.Using Generative Adversarial Networks(GAN)for image conversion can achieve good results.However,if there are enough samples,any image in the target domain can be mapped to the same set of inputs.On this basis,the Cycle Consistency Generative Adversarial Network(CycleGAN)was developed.This article verifies and discusses the advantages and disadvantages of the CycleGAN model in image style conversion.CycleGAN uses two generator networks and two discriminator networks.The purpose is to learn the mapping relationship and inverse mapping relationship between the source domain and the target domain.It can reduce the mapping and improve the quality of the generated image.Through the idea of loop,the loss of information in image style conversion is reduced.When evaluating the results of the experiment,the degree of retention of the input image content will be judged.Through the experimental results,CycleGAN can understand the artist’s overall artistic style and successfully convert real landscape paintings.The advantage is that most of the content of the original picture can be retained,and only the texture line of the picture is changed to a level similar to the artist’s style.展开更多
基金funded by the National Natural Science Foundation of China(82072143,81873943,82360903)Sanming Project of Medicine in Shenzhen(SZSM20162011)+3 种基金Shenzhen Science and Technology Innovation Commission(JCYJ20190806163603504)Shenzhen Second People’s Hospital Clinical Research Fund of Guangdong Province High-level Hospital Construction Project(20203357014,2023xgyj3357001,2023yjlcyj022)Guizhou Science and Technology Planning Project(Guizhou Science and Technology Cooperation Support[2021]General 413)and PhD Start-up Fund(GYZYYFY-BS-2023[09]).
文摘BACKGROUND:Heatstroke has become a common emergency event in hospitals.Procalcitonin(PCT)is used as a biomarker of infection in the emergency department(ED),but its role in rhabdomyolysis(RM)following exertional heatstroke(EHS)remains unclear.METHODS:A retrospective cohort study enrolled patients with EHS from the intensive care unit(ICU).We collected RM biomarkers,inflammation markers,critical disease scores at admission,24 h,48 h,and discharge,and 90-day mortality.Correlation analysis,linear regression and curve fi tting were used to identify the relationship between PCT and RM.RESULTS:A total of 162 patients were recruited and divided into RM(n=56)and non-RM(n=106)groups.PCT was positively correlated with myoglobin(Mb),acute hepatic injury,disseminated intravascular coagulation(DIC),Sequential Organ Failure Assessment(SOFA)score,and Acute Physiology and Chronic Health Evaluation II(APACHE II)score,with correlation coefficients of 0.214,0.237,0.285,0.454,and 0.368,respectively(all P<0.05).Interestingly,the results of curve fi tting revealed a nonlinear relationship between PCT and RM,and a two-piecewise linear regression model showed that PCT was related to RM with an odds ratio of 1.3 and a cut-off of<4.6 ng/mL.Survival analysis revealed that RM was associated with higher mortality compared to non-RM cases(P=0.0093).CONCLUSION:High serum PCT concentrations are associated with RM after EHS in critically ill patients.Elevated PCT concentrations should be interpreted cautiously in patients with EHS in the ED.
基金Supported by National Natural Science Foundation of China(Grant Nos.U23B20104,52075012 and 52205510).
文摘Threaded fasteners are one of the most commonly used connection methods for mechanical structures.Its primary function is to generate appropriate clamping forces and fasten the connected parts.An inappropriate preload can cause loosening,fatigue fracture,and other problems.This will affect the safety and reliability of mechanical equipment.The precise control of the preload has become a critical issue in mechanical assembly processes.Over the past few decades,various tightening measures and methods have been proposed to address this issue.However,many problems continue to exist with practical applications that have not been reviewed comprehensively and systematically.First,various control methods were summarized systematically,and their advantages and disadvantages in engineering applications were analyzed.Torque control is the most widely used tightening method owing to its simple operation and low cost.Therefore,the research on the torque control method was summarized systematically from three aspects:the torque-preload correlation formula,effective friction radius,and friction characteristics during tightening.In addition,the special circumstances that may increase preload uncertainty were discussed.Finally,based on a summary of the current research status,the prospects for future research were discussed.This study would aid researchers in extensively understanding the problems in preload control.
基金supported by funding for research activities of postdoctoral researchers in Anhui Provincespecial funds for developing Anhui Province’s industrial “three highs” and high-tech industries。
文摘The precise measurement of Al, Mg, Ca, and Zn composition in copper slag is crucial for effective process control of copper pyrometallurgy. In this study, a remote laser-induced breakdown spectroscopy(LIBS) system was utilized for the spectral analysis of copper slag samples at a distance of 2.5 m. The composition of copper slag was then analyzed using both the calibration curve(CC) method and the partial least squares regression(PLSR) analysis method based on the characteristic spectral intensity ratio. The performance of the two analysis methods was gauged through the determination coefficient(R^(2)), average relative error(ARE), root mean square error of calibration(RMSEC), and root mean square error of prediction(RMSEP). The results demonstrate that the PLSR method significantly improved both R^(2) for the calibration and test sets while reducing ARE, RMSEC, and RMSEP by 50% compared to the CC method. The results suggest that the combination of LIBS and PLSR is a viable approach for effectively detecting the elemental concentration in copper slag and holds potential for online detection of the elemental composition of high-temperature molten copper slag.
基金supported in part by the Inner Mongolia Autonomous Region Science and Technology Project Fund(2021GG0336)Inner Mongolia Natural Science Fund(2023ZD20).
文摘Accurate short-termphotovoltaic(PV)power prediction helps to improve the economic efficiency of power stations and is of great significance to the arrangement of grid scheduling plans.In order to improve the accuracy of PV power prediction further,this paper proposes a data cleaning method combining density clustering and support vector machine.It constructs a short-termPVpower predictionmodel based on particle swarmoptimization(PSO)optimized Long Short-Term Memory(LSTM)network.Firstly,the input features are determined using Pearson’s correlation coefficient.The feature information is clustered using density-based spatial clustering of applications withnoise(DBSCAN),and then,the data in each cluster is cleanedusing support vectormachines(SVM).Secondly,the PSO is used to optimize the hyperparameters of the LSTM network to obtain the optimal network structure.Finally,different power prediction models are established,and the PV power generation prediction results are obtained.The results show that the data methods used are effective and that the PSO-LSTM power prediction model based on DBSCAN-SVM data cleaning outperforms existing typical methods,especially under non-sunny days,and that the model effectively improves the accuracy of short-term PV power prediction.
文摘<div style="text-align:justify;"> Bearings are widely utilized as key components in industrial scenarios. Therefore, the automatic and precise inspection of bearing defects is imperative for the manufacturing of the bearing. In this paper, a novel defect detection method based on acoustics is proposed to further improve both the accuracy and the efficiency of the defection process. We firstly constructed a labeled dataset composed of acoustic signals sampling from different bearings with a certain rotational speed. OpenSMILE is adopted to extract the acoustic features and the target acoustic feature dataset with 6373 features is formed. To further improve the efficiency of the proposed method, a feature selection strategy based on the chi-square test is adopted to eliminate the most inefficient features. Several statistical learning models are constructed and trained as the classifier. Eventually, the performance of classifiers is evaluated and achieves relatively high accuracy and efficiency with an extremely imbalanced dataset. </div>
基金This work was supported by Scientific Research Starting Project of SWPU[Zheng,D.,No.0202002131604]Major Science and Technology Project of Sichuan Province[Zheng,D.,No.8ZDZX0143]+1 种基金Ministry of Education Collaborative Education Project of China[Zheng,D.,No.952]Fundamental Research Project[Zheng,D.,Nos.549,550].
文摘In the sorting system of the production line,the object movement,fixed angle of view,light intensity and other reasons lead to obscure blurred images.It results in bar code recognition rate being low and real time being poor.Aiming at the above problems,a progressive bar code compressed recognition algorithm is proposed.First,assuming that the source image is not tilted,use the direct recognition method to quickly identify the compressed source image.Failure indicates that the compression ratio is improper or the image is skewed.Then,the source image is enhanced to identify the source image directly.Finally,the inclination of the compressed image is detected by the barcode region recognition method and the source image is corrected to locate the barcode information in the barcode region recognition image.The results of multitype image experiments show that the proposed method is improved by 5+times computational efficiency compared with the former methods,and can recognize fuzzy images better.
文摘Designing low-cost and high-performance photoelectrodes with improved light harvesting and charge separation rates is significant in photoelectrochemical water splitting.Here,a novel TiO2/Cu2O/Al/Al2O3 photoelectrode is manufactured by depositing plasmonic nanoparticles of the non-noble metal Al on the surface of a TiO2/Cu2O core/shell heterojunction for the first time.The Al nanoparticles,which exhibit a surface plasmon resonance(SPR)effect and are substantially less expensive than noble metals such as Au and Ag,generate hot electron-hole pairs and amplify the electromagnetic field at the interface under illumination.The as-prepared TiO2/Cu2O/Al/Al2O3 photoelectrodes have an extended absorption range and enhanced carrier separation and transfer.Their photocurrent density of 4.52 mA·cm^-2 at 1.23 V vs.RHE represents an 1.84-fold improvement over that of TiO2/Cu2O.Specifically,the ultrathin Al2O3 passivation layer spontaneously generated on the surface of Al in air could act as a protective layer to significantly increase its stability.In this work,the synergistic effect of the heterojunctions and the SPR effect of the non-noble metal Al significantly improve the photoelectrode performance,providing a novel concept for the design of electrodes with good properties and high practicability.
基金financial support from the Natural Science Foundation of Tianjin(no.11JCYBJC27000)
文摘Highly efficient sheet-like BiPO4/zeolite and ball-flower-like BiPO4/zeolite had been successfully synthesized by a standard hydrothermal method. The addition of assistant reagent in the hydrothermal system is promising to obtain special morphology. The assistant reagent (EDTA) acts as a growth modifier of crystal. The possible formation mechanisms of sheet-like BiPO4/zeolite and ball-flower-like BiPO4/zeolite were schematically discussed. A detailed study of sheet-like BiPO4/zeolite and ball-flower-like BiPO4/zeolite impacted on the photodecoloration methylene blue (MB) solution showed that the composite had a highly reusable and stable property for long-run photocatalytic application. (C) 2016 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. and Science Press. All rights reserved.
基金the Second Tibetan Plateau Scientific Expedition and Research Program(Grant No.2019QZKK0405)the National Natural Science Foundation of China(Grant No.41871185&41971270)。
文摘The Tibetan Plateau(TP)is undergoing rapid urbanization.To improve urban sustainability and construct eco-logical security barriers,it is essential to quantify the spatial patterns of urbanization level on the TP,but the existing studies on the topic have been limited by the lack of socioeconomic data.This study aims to quantify the urbanization level on the TP in 2018 with Luojia1-01(LJ1-01)high-resolution nighttime light(NTL)data.Specifically,the compounded night light index is used to quantify spatial patterns of urbanization level at mul-tiple scales.The results showed that the TP had a low overall urbanization level with a large internal difference.The urbanization level in the northeast,southeast and south of the TP was relatively high,forming three hotspots centered in Xining City,Lhasa City and Shangri-La City,while the urbanization level in the central and western regions was relatively low.The analysis of influencing factors,based on the random forest model,showed that transportation and topography were the main factors affecting the TP’s spatial patterns of urbanization level.The comparison analysis with socioeconomic statistics and traditional NTL data showed that LJ1-01 NTL data can be used to more effectively quantify the urbanization level since it is more advantageous for reflecting the spatial extent of urban land and describing the spatial structure of socioeconomic activities within urban areas.These advantages are attributed to the high spatial resolution of the data,appropriate imaging time and unaf-fected by saturation phenomena.Thus,the proposed LJ1-01 NTL-based urbanization level measurement method has the potential for wide applications around the world,especially in less-developed regions lacking statistical data.Using this method,we refined the measurement of the TP’s urbanization level in 2018 for multiple scales including the region,basin,prefecture and county levels,which provides basic information for the further urban sustainability research on the TP.
基金The National Science and Technology Major Project of the Ministry of Science and Technology of China under contract No.2016ZX05024-002
文摘Through the analysis of the faults and their internal structure in Zhu I Depression,it is found that the internal structure of the late fault is obviously segmented vertically.It develops unitary structure(simple fault plane)in shallow layers,binary structure(induced fracture zone in hanging wall and sliding fracture zone in footwall)in middle,layers and ternary structure(induced fracture zone in hanging wall and sliding fracture zone in middle,and induced fracture zone in footwall)in deep layers.Because the induced fracture zone is a high porosity and permeability zone,and the sliding fracture zone is a low porosity and ultra-low permeability zone,the late fault in middle layers has the character of"transporting while sealing".The late fault can transport hydrocarbon by its induced fracture zone in the side of the hanging wall and seal hydrocarbon by its sliding fracture zone in the side of the footwall.In deep layers,the late fault has the character of"dual-transportation",induced fracture zones in both sides of hanging wall and footwall can transport hydrocarbon.The early fault that only developed in the deep layers is presumed to be unitary structure,which plays a completely sealing role in the process of hydrocarbon migration and accumulation due to inactivity during the hydrocarbon filling period.Controlled by hydrocarbon source,early/late faults,sand bodies and traps,two reservoir-forming models of"inverted L"and"stereo-spiral"can be proposed in middle layers,while two reservoir-forming models of"cross fault"and"lateral fault sealing"are developed in the deep layers of Zhu I Depression.
基金financial support from Tianjin Science and Technology Support Plan Key Projects(NO.12ZCZDJC35600)
文摘The highly ordered TiO2 nanotubes (NTs) were fabricated by the anodic oxidation method. Their morphology, structure and crystalline phase were characterized by scanning electron microscopy (SEM) and X-ray diffractometer (XRD). The effects of morphology, specific surface area, pore structures and photo catalytic activity of the TiO2 NTs were investigated. UV-vis spectra analysis showed that its light absorption had been extended to the visible light range. The photocatalytic activity of the as-prepared samples was evaluated by photocatalytic oxidation of gaseous HCHO and MB aqueous solution. The samples had better adhesion strength in the dark and showed a higher photocatalytic activity than nanoparticles. Especially, with ultraviolet light pretreatment, the nanotubes exhibited more stable active for photocatalytic decomposition and the photodecomposition rate remained at high level after 3 cycles of the photocatalysis experiment. Thus, how the number of surface active group center dot OH increased and the mechanism for the great improvement for the photocatalytic activity are discussed. (C) 2016 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. and Science Press. All rights reserved.
基金This research was supported by the National Natural Science Foundation of China(71861008,72063005,U1811462,71532009)the Natural Science Foundation of Hainan Province(718QN221,2019RC151)the Scientific Research Foundation of Hainan University(kyqd(sk)1809,kyqd1634).
文摘This paper investigates the impact of economic policy uncertainty(EPU)on the crash risk of US stock market during the COVID-19 pandemic.To this end,we use the GARCHS(GARCH with skewness)model to estimate daily skewness as a proxy for the stock market crash risk.The empirical results show the significantly negative correlation between EPU and stock market crash risk,indicating the aggravation of EPU increase the crash risk.Moreover,the negative correlation gets stronger after the global COVID-19 outbreak,which shows the crash risk of the US stock market will be more affected by EPU during the epidemic.
基金supported by the National Natural Science Foundation of China(81704193).
文摘External therapy,which has been used for millennia to treat disease,has now become the newest member of complementary and alternative therapies.A growing number of clinical studies and animal experiments have shown that external therapy exerts a positive effect on the intestinal flora.In this paper,we review the research related to external therapy on various systemic diseases and focus on changes in the intestinal flora.We found that studies on external therapy are dominated by acupuncture and tuina,primarily aimed at the treatment of digestive and neurological diseases.However,the deeper mechanism of regulation of the intestinal flora by external therapy has not yet been experimentally confirmed.
基金supported by the National Natural Science Foundation of China (81873392)the Beijing Natural Science Foundation (7192113)
文摘Objective: To investigate the changes in the hypothalamic metabolites of lipopolysaccharide(LPS) febrile young rabbits after the treatment with pediatric tuina.Methods: A total of 30 young rabbits were randomly assigned into three groups: the normal group, the model group, and the tuina group. Both the model group and the tuina group were injected intravenously with LPS. “Six antipyretic manipulations”(pushing Tianmen, pushing Kangong, kneading Taiyang,kneading Erhougaogu, clearing Tianheshui, and pushing Jizhu) were administered 1 h after the LPS injection in the tuina group. The rectal temperatures of the young rabbits were monitored during the experiment to explore the antipyretic effect. Three hours after the injection, the content of interleukin-1β(IL-1β), tumor necrosis factor(TNF)-a, and prostaglandin E;(PGE;) in the serum was detected. In addition, liquid chromatography-mass spectrometry(LC-MS) was used for the hypothalamus metabolomics.Results: Compared with the model group, the rectal temperature of the tuina group was decreased at 2 h and 3 h after the LPS injection(P =.04, P =.03, respectively), and the content of IL-1β, TNF-a, and PGE2was decreased(P =.03, P =.003, and P =.008, respectively). The metabolomics results showed that there were 23 potential biomarkers after the tuina intervention, enriching 27 pathways. Lipid metabolites,especially glycerophospholipids, were a majority of the altered metabolites. The primary metabolic pathways affected by tuina included the arachidonic acid metabolism, the GABAergic synapse, D-glutamine and D-glutamate metabolism, and the glutamatergic synapse.Conclusion: Pediatric tuina reduced the temperature of the febrile rabbits and downregulated the expression of IL-1β, TNF-a, and PGE2, and the antipyretic mechanism may be related to changes in metabolites and metabolic pathways in the hypothalamus.
基金supported by the Science Funds of Tianjin for Distinguished Young Scholar(17JCJQJC44800)Natural Science Foundation of Tianjin(16JCYBJC17900)Open Foundation of Hubei Collaborative Innovation Center for High-efficient Utilization of Solar Energy(HBSKFZD2017001)~~
文摘We report on a novel g-C3N4/TiO 2/Co-Pi photoanode combining a TiO2 protection layer, Co-Pi hole capture layer, and g-C3 N4 light-absorption layer layer for photoelectrochemical(PEC) water splitting to generate hydrogen for the first time. This new photoanode with three function layers exhibits enhanced PEC performance with a photocurrent density of 0.346 mA ·cm–2 at 1.1 V(vs. RHE),which is approximately 3.6 times that of pure g-C3N4 photoanode. The enhanced PEC performance of g-C3N4/TiO 2/Co-Pi photoanode benefits from the following:(1) excellent visible light absorption of g-C3N4;(2) stable protection of TiO2 to improve the durability of g-C3N4 film; and(3) photogenerated holes capture Co-Pi to separate photogenerated electron-hole pairs efficiently. This promising multifarious function layers structure provides a new perspective for PEC water splitting to generate hydrogen.
基金The National Key R&D Program of China under contract No.2018YFD0900102the Key Research and Development Plan of Nation under contract No.2018YFD0900301+2 种基金the AoShan Talents Cultivation Program Supported by Pilot National Laboratory for Marine Science and Technology(Qingdao)under contract No.2017ASTCP-OS04the Earmarked Fund for the Modern AgroIndustry Technology Research System under contract No.CARS-47-G01the Central Public-interest Scientific Institution Basal Research Fund under contract No.2020TD25.
文摘The aim of this study was to evaluate the genetic parameters of the growth performance of Takifugu rubripes.Heritabilities and genetic correlations were estimated for body weight(BW),body length(BL),total length(TL),chest measurement(CM)and trunk length(TKL)of T.rubripes from measurements of progeny at 6 months and 12 months.The results showed that the heritability was 0.37 for BW6,0.19 for BL6,0.35 for TL6,0.29 for CM6,0.26 for TKL6,0.36 for BW12,0.26 for BL12,0.25 for TL12,0.31 for CM12 and 0.15 for TKL12.The range of genetic correlations estimated at 6 months was 0.025–0.725 and−0.002–0.706 at 12 months.The results indicated that genetic improvement for faster growth rate or increased body weight in cultured T.rubripes was effective.Based on selection theory,the selection strategy for traits with medium heritability is flexible.Considering that these growth traits do not reach the high level of heritability,family selection should be expected.Given positive genetic correlations among BW,BL,TL,CM,and TKL at 6 months,the five traits could be improved simultaneously through selective breeding.As there was high genetic correlation only between BW12,BL12 and TL12,and negative correlations between TKL12 and BL12 as well as between CM12 and TL12,and only BW,BL and TL at 12 months could be improved simultaneously.
文摘When using shape memory materials into active disassembly of actual electronic products, because the elastic modulus of shape memory materials is affected by the temperature is relatively large, therefore, the main difference of environmental reliability between active disassembly products and common products is the impact of collision and vibration under different temperature. Establishing three-dimensional analysis model, comparing the impact of collision and vibration of mobile phone shells which are made up of PVC materials after casting & radiation and PC/ABS materials under different temperature. Analyzing the reliability of mobile phone under different temperature and optimizing its structure according to data of testing.
基金supported by Scientific Research Starting Project of SWPU(No.0202002131604)Major Science and Technology Project of Sichuan Province(No.8ZDZX0143)+1 种基金Ministry of Education Collaborative Education Project of China(No.952)Fundamental Research Project(Nos.549,550).
文摘There are two difficult in the existing image restoration methods.One is that the method is difficult to repair the image with a large damaged,the other is the result of image completion is not good and the speed is slow.With the development and application of deep learning,the image repair algorithm based on generative adversarial networks can repair images by simulating the distribution of data.In the process of image completion,the first step is trained the generator to simulate data distribution and generate samples.Then a large number of falsified images are quickly generated using the generative adversarial network and search for the code of the closest damaged image.Finally,the generator generates missing content by using this code.On this basis,this paper combines the semantic loss function and the perceptual loss function.Experimental result show that the method successfully predicts the information of large areas missing in the image,and realizes the photorealism,producing clearer and more consistent results than previous methods.
基金supported by Scientific Research Starting Project of SWPU[No.0202002131604]Major Science and Technology Project of Sichuan Province[Nos.8ZDZX0143,2019YFG0424]+1 种基金Ministry of Education Collaborative Education Project of China[No.952]Fundamental Research Project[Nos.549,550].
文摘Image conversion refers to converting an image from one style to another and ensuring that the content of the image remains unchanged.Using Generative Adversarial Networks(GAN)for image conversion can achieve good results.However,if there are enough samples,any image in the target domain can be mapped to the same set of inputs.On this basis,the Cycle Consistency Generative Adversarial Network(CycleGAN)was developed.This article verifies and discusses the advantages and disadvantages of the CycleGAN model in image style conversion.CycleGAN uses two generator networks and two discriminator networks.The purpose is to learn the mapping relationship and inverse mapping relationship between the source domain and the target domain.It can reduce the mapping and improve the quality of the generated image.Through the idea of loop,the loss of information in image style conversion is reduced.When evaluating the results of the experiment,the degree of retention of the input image content will be judged.Through the experimental results,CycleGAN can understand the artist’s overall artistic style and successfully convert real landscape paintings.The advantage is that most of the content of the original picture can be retained,and only the texture line of the picture is changed to a level similar to the artist’s style.