The Jurassic strata constitute a focal area for recent exploration and development of tight gas reservoirs in the western Sichuan Basin. This study investigates the Jurassic Shaximiao Formation in ...the northern Longmenshan in the Western Sichuan basin, focusing on tight gas reservoirs. The research integrates core and outcrop observations, seismic interpretations, and burial history analyses to understand hydrocarbon source rocks, sedimentation, reservoir characteristics, and structural characteristics. The impact of Yanshan-Himalayan tectonic movements on tight gas reservoir accumulation in the Shaximiao Formation is dissected, primarily around the Qiulin structure. The Western Sichuan Depression basin’s formation is influenced by gravitational gliding tectonics, which can be classified into the ‘Three Zones and One Belt,’ with Longmenshan in the frontal belt. Burial history analysis reveals distinct processes in the foreland belt and the depression basin. In the Qiulin area, gas reservoirs in the Shaximiao Formation are mainly charged by source rocks from the Xujiahe Formation. Tectonic movements play a significant role in creating favorable reservoirs and conditions for hydrocarbon migration and preservation. Natural gas accumulation is primarily controlled by fault connectivity to hydrocarbon sources and effective reservoir thickness. Gravitational sliding tectonics have shaped a fluvial-lacustrine environment for the Shaximiao Formation, with fluvial sand bodies acting as favorable reservoir zones. Small-scale normal faults formed by tectonic movements serve as conduits for natural gas migration. The research findings are of significant guidance for the exploration and development of tight oil and gas resources in western Sichuan basin.
The past several decades have witnessed the successful application of sequential Monte Carlo method (or particle filter) to a variety of fields. It has grown to be a popular method in solving ...different kinds of nonlinear Bayesian estimation problems. This paper introduces a two-stage particle filter for nonlinear filtering problem. In the proposed particle filter, each particle will be propagated and updated through two stages. At time step <inline-formula> <tex-math notation="LaTeX">t </tex-math></inline-formula>, the first stage refers to using the unscented Kalman filtering equations to propagate the particles from time step <inline-formula> <tex-math notation="LaTeX">t-1 </tex-math></inline-formula> in order to obtain the preliminary estimations. Then, at the second stage, the particles will be updated again by the iterated extended Kalman filter to yield the final updated particles. In this way, the estimation accuracy of particle filter can be improved, which is validated through simulation experiments and real-world application experiments.
Injuries are a growing public health concern in China, accounting for more than 30% of all Person Years of Life Lost (PYLL) due to premature mortality. This study analyzes the trend and disease ...burden of injury deaths in Chinese population from 2004 to 2010, using data from the National Disease Surveillance Points (DSPs) system, as injury deaths are classified based on the International Classification of Disease-10(th) Revision (ICD-10). We observed that injury death accounted for nearly 10% of all deaths in China throughout the period 2004-2010, and the injury mortality rates were higher in males than those in females, and higher in rural areas than in urban areas. Traffic crashes (33.79-38.47% of all injury deaths) and suicides (16.20-22.01%) were the two leading causes of injury deaths. Alarmingly, suicide surpassed traffic crashes as the leading cause of injury mortality in rural females, yet adults aged 65 and older suffered the greatest number of fatal falls (20,701 deaths, 2004-2010). The burden of injury among men (72.11%) was about three times more than that of women's (28.89%). This study provides indispensible evidence that China Authority needs to improve the surveillance and deterrence of three major types of injuries: Traffic-related injury deaths should be targeted for injury prevention activities in all population, people aged 65+ should be encouraged to take individual fall precautions, and prevention of suicidal behavior in rural females should be another key priority for the government of China.
The main purpose of visual servoing is to control the motion of a robot system based on visual information provided by one or more cameras. It is an important research topic in the robotics ...community. In uncalibrated visual servoing, the image Jacobian matrix estimation is of great importance to the success of visual servoing control. This paper addresses the online estimation of the total Jacobian matrix for robot visual servoing using the unscented particle filter. We first give the definition of the total Jacobian matrix and formulate the total Jacobian matrix estimation problem into Bayesian filtering framework. Then, we propose to estimate the total Jacobian matrix using the unscented particle filter. Each particle is propagated and updated using the unscented Kalman filter equations. Such an update can make full use of the image feature measurements and consequently generate more accurate estimation results. The simulation results on a 2DOF robot visual servoing platform show that the proposed method provides accurate and reliable performance in the object tracking task.
The Knee Injury and Osteoarthritis Outcome Score (KOOS) has been utilized to evaluate short- and long-term outcomes in individuals following knee injuries, such as those with anterior cruciate ...ligament reconstruction and knee osteoarthritis, but has not yet been applied to individuals undergoing total knee arthroplasty (TKA) in China. The aim of this study was to assess the psychometric properties of the Simplified Chinese version of the KOOS in Chinese individuals undergoing TKA.
This study distributed 170 questionnaires, and assessed the KOOS of the participants, along with requiring them to complete the Short Form 36 (SF-36) survey. There were 35 participants completed a test-retest reliability survey with a 24-h interval, 129 participants completed a pre - surgery survey, and 119 individuals completed a post - surgery survey 6 weeks after the surgery. The following tests were conducted: Cronbach's alpha (α) to assess internal consistency, intraclass correlation coefficient (ICC) to evaluate test-retest reliability, Spearman's correlation coefficient (ρ) to examine construct validity, effect size (ES) to detect measure responsiveness, minimal detectable change (MDC) to assess measurement errors. Floor and ceiling effects (<15%) were also asses evaluated.
The simplified Chinese version of the KOOS showed good test-retest reliability in participants after TKA, with an ICC of 0.82–0.97 (95% CI). The internal consistency of the five subscales of the KOOS was good (Cronbach's α = 0.70–0.96). No floor or ceiling effects were found. Regarding construct validity, a strong positive correlation was found between each of the three KOOS subscales (activities of daily living, knee-related Quality of Life, and sport and recreation subscales) and the general health and bodily pain subscales of the SF-36 (0.53 < ρ < 0.61). The subscales of the simplified Chinese version of the KOOS showed responsiveness (ES: 0.68 to 0.86) before and after 6 weeks of physical treatment. The MDC ranged from 10.28 to 23.24.
The Chinese version of the KOOS showed good psychometric properties and was found to be valid, reliable, and simple as an assessment tool for symptoms, pain, activity of daily living, sports and recreational activity and quality of life for the Chinese population suffering from TKA.
Patients diagnosed with influenza and upper respiratory tract infections (URTIs) have similar clinical manifestations and biochemical indices and a low detection rate of viral pathogens, mixed ...infection with diverse respiratory viruses, and targeted antiviral treatment difficulty in the early stage. According to the treatment strategy of "homotherapy for heteropathy" in traditional Chinese medicine (TCM), different diseases with the same clinical symptoms can be treated with the same medicines. Qingfei Dayuan granules (QFDY), a type of Chinese herbal preparation included in the
issued by the Health Commission of Hubei Province in 2021, are recommended for patients suffering from COVID-19 with symptoms of fever, cough, and fatigue, among others. Additionally, recent studies have shown that QFDY effectively alleviates fever, cough, and other clinical symptoms in patients with influenza and URTIs.
The study was designed as a multicenter, randomized, double-blind, placebo-controlled clinical trial for treatment for influenza and URTIs manifested by pulmonary heat-toxin syndrome (PHTS) with QFDY. A total of 220 eligible patients were enrolled from eight first-class hospitals in five cities of Hubei Province in China and randomly assigned to receive either 15 g of QFDY or a placebo three times a day for 5 days. The primary outcome was the complete fever relief time. Secondary outcomes included efficacy evaluation of TCM syndromes, scores of TCM syndromes, cure rate of each single symptom, incidence of comorbidities and progression to severe conditions, combined medications, and laboratory tests. Safety evaluations mainly involved adverse events (AEs) and changes in vital signs during the study.
Compared with the placebo group, the complete fever relief time was shorter in the QFDY group, 24 h (12.0, 48.0) in the full analysis set (FAS) and 24 h (12.0, 49.5) in the per-protocol set (PPS) (
≤ 0.001). After a 3-day treatment, the clinical recovery rate (22.3% in the FAS and 21.6% in the PPS) and cure rate of cough (38.6% in the FAS and 37.9% in the PPS), a stuffy and running nose, and sneezing (60.0% in the FAS and 59.5% in the PPS) in the QFDY group were higher than those in the placebo group (
< 0.05). The number of patients taking antibiotics for more than 24 h in the placebo group (nine cases) was significantly higher than that in the QFDY group (one case) (
< 0.05). There were no significant differences between the two groups in terms of scores of TCM syndromes, incidence of comorbidities or progression to severe conditions, combined use of acetaminophen tablets or phlegm-resolving medicines, and laboratory tests (
> 0.05). Meanwhile, no significant difference was found in the incidence of AEs and vital signs between the two groups (
> 0.05).
The trial showed that QFDY was an effective and safe treatment modality for influenza and URTIs manifested by PHTS because it shortened the complete fever relief time, accelerated clinical recovery, and alleviated symptoms such as cough, a stuffy and running nose, and sneezing during the course of treatment.
https://www.chictr.org.cn/showproj.aspx?proj=131702, identifier ChiCTR2100049695.
Horizontal well and large-scale hydraulic fracturing are the main technical means for tight gas development at present. However, tight gas reservoirs are characterized by strong heterogeneity, and ...different types of gas Wells have different production characteristics and pressure propagation laws. In view of the above problems, based on the physical characteristics and reservoir reconstruction evaluation of tight gas reservoir in GAS Reservoir A in Sichuan Basin, three types of reservoir hydraulic fracture models and numerical simulation models were generated by using numerical simulation method, and the production dynamic prediction and pressure wave propagation law were studied. The simulation results show that: (1) In the beginning of production, the deflated area is mainly hydraulic fracture reconstruction area, and the drainage radius of all kinds of gas Wells expands at similar speed; (2) When the drainage range is expanded in the untransformed area, the dimensionless drainage radius expansion speed of gas well is positively correlated with the reservoir physical property. The dimensionless drainage radius and drainage area of class I and II horizontal Wells are relatively faster, while that of Class III Wells is slightly slower.
Abstract
In order to improve the performance of garbage collection truck manipulators, a three-dimensional model of the garbage collection truck manipulator is established based on SolidWorks. The ...dynamic analysis of the garbage collection truck manipulator model is carried out using the ADAMS software according to its movement in different working conditions, obtaining the displacement, force, and speed curves. The model is identical to garbage collection truck manipulators used in real situations. The static characteristics of the garbage collection truck manipulator model are analyzed in HyperWorks, which provides the conditions for the subsequent optimization. Finally, based on parametric modeling, taking the volume minimum as the goa, keeping the deformation and stress to meet the requirements for use as constraints, a genetic algorithm is used to optimize the weight of the manipulator. The optimization results show that the mass of the manipulator can be reduced by 17 kg (16.73%) while the strength meets the requirements.
•2-Methyltetrahydrofuran production from furfural using a trimetallic catalyst.•Cu nanoparticles on the Hβ surface became smaller after doping Ni or Re.•The adsorption configurations of reactants on ...the catalyst were determined.•The hydrogenation and hydrodeoxygenation sites of the catalyst were determined.
The direct conversion of furfural (FUR) to 2-methyltetrahydrofuran (2-MTHF) was investigated over a trimetallic CuNiRe/Hβ catalyst. Under optimal reaction conditions at 240 °C under 3 MPa H2 for 1 h, almost complete conversion of FUR and high-yield of 2-MTHF (81 %) was achieved. This is the highest yield reported for the direct conversion of FUR to 2-MTHF. HR-TEM demonstrated that the growth of Cu nanoparticles (NPs) on the surface of Hβ was inhibited after loading Ni or Re resulted in the smaller Cu particle size and better hydrogenation and hydrodeoxygenation activity. H2-TPR characterization exhibited that the reducibility of bimetallic and trimetallic catalysts was higher than that of monometallic catalysts·NH3-TPD explained that Hβ acid sites mainly contributed to FUR deoxygenation. The adsorption configurations of FUR, furfuryl alcohol (FOL) and 2-methylfuran (2-MF) on the catalyst were revealed by ATR-IR. Catalyst evaluation and control experiments proved that FUR was first hydrogenated to FOL, followed by hydrodeoxygenation to 2-MF, and finally hydrogenated to 2-MTHF catalyzed by the combination of three metals.
SrSi2O2N2:Ce3+/Eu2+ phosphors have been synthesized with a high-temperature solid-state reaction method. The result shows that effective energy transfer has occurred between Ce3+ and Eu2+. The energy ...transfer efficiency was calculated, and the mechanism was determined as dipole-dipole interaction. The Influence of co-doping with a charge compensator M+ (M+ = Li+, Na+, K+) on the photoluminescence properties of SrSi2O2N2:Ce3+/Eu2+ was analyzed. It is clear that the PL properties of the SrSi2O2N2:Ce3+/Eu2+ phosphor are significantly improved by doping with Li+/Na+/K+, and the Li+ ions is the best charge compensator for this phosphor.
•An effective energy transfer from Ce3+ to Eu2+ has occurred in Ce3+, Eu2+ co-doped SrSi2O2N2 phosphors.•The photoluminescence spectra of SrSi2O2N2:Ce3+/Eu2+ phosphors cover the emission band of Eu2+ and Ce3+.•The emission color is tunable via changing the ratio of Ce3+ and Eu2+ doping concentration.•The enhancement effect of M+ co-doping in SrSi2O2N2:Ce3+/Eu2+/M+ is ranked Li>Na > K.
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