The problem of the unmanned surface vessel (USV) path planning in static and dynamic obstacle environments is addressed in this paper. Multi-behavior fusion based potential field method is proposed, which contains thr...
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The problem of the unmanned surface vessel (USV) path planning in static and dynamic obstacle environments is addressed in this paper. Multi-behavior fusion based potential field method is proposed, which contains three behaviors: goal-seeking, boundary-memory following and dynamic-obstacle avoidance. Then, different activation conditions are designed to determine the current behavior. Meanwhile, information on the positions, velocities and the equation of motion for obstacles are detected and calculated by sensor data. Besides, memory information is introduced into the boundary following behavior to enhance cognition capability for the obstacles, and avoid local minima problem caused by the potential field method. Finally, the results of theoretical analysis and simulation show that the collision-free path can be generated for USV within different obstacle environments, and further validated the performance and effectiveness of the presented strategy.
Objective:To explore the clinical efficacy of sodium oligomannate capsules combined with memantine hydrochloride and donepezil hydrochloride in the treatment of moderate Alzheimer’s disease(AD)and analyze its impact ...
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Objective:To explore the clinical efficacy of sodium oligomannate capsules combined with memantine hydrochloride and donepezil hydrochloride in the treatment of moderate Alzheimer’s disease(AD)and analyze its impact on cognitive ***:Eighty patients with moderate AD admitted to the neurology outpatient clinic of our hospital from June 2021 to December 2022 were selected as the study subjects and randomly divided into a study group and a control group,each with 40 *** control group was treated with oral memantine hydrochloride and donepezil hydrochloride,while the study group was additionally treated with oral sodium oligomannate capsules for 24 *** scores of neuropsychological scales[Montreal Cognitive Assessment(MoCA)and Mini-Mental State Examination(MMSE)],and Activities of Daily Living(ADL)scale were compared before and after ***,the levels of homocysteine(Hcy),central nervous system-specific protein(S100-β),interleukin(IL)-6,and tumor necrosis factor(TNF)-αwere measured in both groups,and the treatment effects and adverse reactions were ***:After 24 weeks of treatment,the MMSE,MoCA,and ADL scores of both groups were significantly higher than those before treatment(P0.05).Conclusion:The combination of sodium oligomannate capsules,memantine hydrochloride,and donepezil hydrochloride is effective in the treatment of moderate *** can improve the cognitive function and daily living abilities of patients with dementia,enhancing their quality of life.
To improve the understanding of the transport mechanism in shale gas reservoirs and build a theoretical basic for further researches on productivity evaluation and efficient exploitation, various gas transport mechani...
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To improve the understanding of the transport mechanism in shale gas reservoirs and build a theoretical basic for further researches on productivity evaluation and efficient exploitation, various gas transport mechanisms within a shale gas reservoir exploited by a horizontal well were thoroughly investigated, which took diffusion, adsorption/desorption and Darcy flow into account. The characteristics of diffusion in nano-scale pores in matrix and desorption on the matrix surface were both considered in the improved differential equations for seepage flow. By integrating the Langmuir isotherm desorption items into the new total dimensionless compression coefficient in matrix, the transport function and seepage flow could be formalized, simplified and consistent with the conventional form of diffusion equation. Furthermore, by utilizing the Laplace change and Sethfest inversion changes, the calculated results were obtained and further discussions indicated that transfer mechanisms were influenced by diffusion, adsorption/desorption. The research shows that when the matrix permeability is closed to magnitude of 10^-9D, the matrix flow only occurs near the surfacial matrix; as to the actual production, the central matrix blocks are barely involved in the production; the closer to the surface of matrix, the lower the pressure is and the more obvious the diffusion effect is; the behavior of adsorption/desorption can increase the matrix flow rate significantly and slow down the pressure of horizontal well obviously.
Mach number effects on the near-wall turbulence in the absence of outer motions remain unclear so *** present study extends the Minimal Flow Units(MFUs),a widely applied method to investigate near-wall turbulence free...
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Mach number effects on the near-wall turbulence in the absence of outer motions remain unclear so *** present study extends the Minimal Flow Units(MFUs),a widely applied method to investigate near-wall turbulence free from the impact of large-scale motions in the outer region in incompressible channel flows,to compressible wall-bounded *** compressible near-wall turbulence in MFU proves accurate in replicating near-wall statistics,independent of Mach number and statistically equivalent to the universal signals extracted from the full-sized *** is further utilized as universal signals in the predictive models of compressible near-wall turbulence,which is capable of accurately predicting variances and joint probability density functions of velocity and temperature fluctuations.
Background:Heatwaves have a significant impact on population health including both morbidity and *** this study we examined the association between heatwaves and emergency hospital admissions(EHAs)for renal diseases i...
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Background:Heatwaves have a significant impact on population health including both morbidity and *** this study we examined the association between heatwaves and emergency hospital admissions(EHAs)for renal diseases in children(aged 0-14 years)in Brisbane,***:Daily data on EHAs for renal diseases in children and exposure to temperature and air pollution were obtained for Brisbane city from January 1,1996 to December 31,2005.A time-stratified case-crossover design was used to compare the risks for renal diseases between heatwave and non-heatwave ***:There were 1565 EHAs for renal diseases in children during the study *** exhibited a signifi cant impact on EHAs for renal diseases in children after adjusting for confounding factors(odds ratio:3.6;95%confidence interval:1.4-9.5).The risk estimates differed with lags and the use of different heatwave defi ***:There was a significant increase in EHAs for renal diseases in children during heatwaves in Brisbane,a subtropical city where people are well accustomed to warm *** finding may have significant implications for pediatric renal care,particularly in subtropical and tropical regions.
Road safety performance function(SPF) analysis using data-driven and nonparametric methods, especially recent developed deep learning approaches, has gained increasing achievements. However, due to the learning mechan...
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Road safety performance function(SPF) analysis using data-driven and nonparametric methods, especially recent developed deep learning approaches, has gained increasing achievements. However, due to the learning mechanisms are hidden in a"black box" in deep learning, traffic features extraction and intelligent importance analysis are still unsolved and hard to *** paper focuses on this problem using a deciphered version of deep neural networks(DNN), one of the most popular deep learning models. This approach builds on visualization, feature importance and sensitivity analysis, can evaluate the contributions of input variables on model's "black box" feature learning process and output decision. Firstly, a visual feature importance(Vi FI) method that describes the importance of input features is proposed by adopting diagram and numerical-analysis. Secondly,by observing the change of weights using Vi FI on unsupervised training and fine-tuning of DNN, the final contributions of input features are calculated according to importance equations for both steps that we proposed. Sequentially, a case study based on a road SPF analysis is demonstrated, using data collected from a major Canadian highway, Highway 401. The proposed method allows effective deciphering of the model's inner workings and allows the significant features to be identified and the bad features to be eliminated. Finally, the revised dataset is used in crash modeling and vehicle collision prediction, and the testing result verifies that the deciphered and revised model achieves state-of-theart performance.
Molecular dynamics simulation technique is used to investigate the ionic conduction property of the fast-ion conductor calcia-stabilized zirconia(CSZ).The theoretical results coincide with experimental measurements **...
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Molecular dynamics simulation technique is used to investigate the ionic conduction property of the fast-ion conductor calcia-stabilized zirconia(CSZ).The theoretical results coincide with experimental measurements *** is suggested that the dopant cation distribution is a key factor controlling the ionic conduction property of the CSZ electrolytes,which can be used as a rule in the microstructure designing and controlling in material processing.
BACKGROUND Severe total colonic necrosis,septic shock and venous thromboembolism secondary to ulcerative colitis (UC) are rare and *** such severe complications have been reported in the *** SUMMARY We report a 36-yea...
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BACKGROUND Severe total colonic necrosis,septic shock and venous thromboembolism secondary to ulcerative colitis (UC) are rare and *** such severe complications have been reported in the *** SUMMARY We report a 36-year-old woman who developed total colonic necrosis and septic shock secondary to *** patient was treated with emergency surgery because computed tomography showed suspicious *** massive ascites occurred after operation and computed tomography angiography demonstrated portal vein,mesenteric vein and splenic vein *** patient was discharged from hospital after active *** Clinicians should pay attention to venous thrombosis,colonic necrosis and septic shock in UC *** observation of surgical indications and timely surgical intervention are the key to reduce mortality and complications in UC.
BACKGROUND: Chronic hepatitis B virus (HBV) infection remains a major global health issue, and the prognosis of patients with HBV-associated fulminant hepatic failure is extremely poor. The application of antiviral th...
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BACKGROUND: Chronic hepatitis B virus (HBV) infection remains a major global health issue, and the prognosis of patients with HBV-associated fulminant hepatic failure is extremely poor. The application of antiviral therapies has led to significant improvements in patient outcomes. This article aimed to review the current strategies in antiviral treatment of HBV-associated fulminant hepatic failure. DATA SOURCES: Literature search was conducted using PubMed on the related subjects. Part of the data was from the most recent work of the authors' laboratory. RESULTS: Hepatitis B immunoglobulin in prevention of recurrent HBV infection after orthotopic liver transplantation (OLT) has been proven effective. However, its cost is high, and significant side effects have been found to induce viral mutations. Lamivudine has a potent suppression for HBV replication and an excellent safety profile in decompensated cirrhotic patients, but its major drawback is the high rate of drug-resistance. Adefovir is effective for lamivudine-resistance strains in the post-OLT situation, and its drug-resistance rate is relatively low. Combination therapies such as hepatitis B immunoglobulin combined with lamivudine and lamivudine combined with adefovir have been widely adopted for prophylaxis against HBV recurrence of infection after OLT. Entecavir, telbivudine, tenofovir and other newer agents have been widely used in antiviral therapy. CONCLUSIONS: The prognosis of HBV-associated fulminant hepatic failure is being transformed by developments in antiviral therapy. However, it should be noticed that HBV is controlled but never eliminated, and drug-resistance still remains a major issue. Hopefully, newer strategies may help to solve these problems.
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