The train schedule usually includes train stop schedule,routing scheme and formation *** is the basis of subway *** the practical experience of transport organizations and the principle of the best match between trans...
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The train schedule usually includes train stop schedule,routing scheme and formation *** is the basis of subway *** the practical experience of transport organizations and the principle of the best match between transport capacity and passenger flow demand,taking the minimum value of passenger travel costs and corporation operating costs as the goal,considering the constraints of the maximum rail capacity,the minimum departure frequency and the maximum available electric multiple unit,an optimization model for city subway Y-type operation mode is constructed to determine the operation section of mainline as well as branch line and the train frequency of the Y-type operation *** particle swarm optimization(PSO)algorithm based on classification learning is used to solve the model,and the effectiveness of the model and algorithm is verified by a practical *** results show that the length of branch line in Y-type operation affects the cost of waiting time of passengers significantly.
Objective:To elucidate how spinal manipulative therapy(SMT)exerts its analgesic effects through regulating brain function in lumbar disc herniation(LDH)patients by utilizing resting-state functional magnetic resonance...
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Objective:To elucidate how spinal manipulative therapy(SMT)exerts its analgesic effects through regulating brain function in lumbar disc herniation(LDH)patients by utilizing resting-state functional magnetic resonance imaging(rs-f MRI).Methods:From September 2021 to September 2023,we enrolled LDH patients(LDH group,n=31)and age-and sex-matched healthy controls(HCs,n=28).LDH group underwent rs-f MRI at 2 distinct time points(TPs):prior to the initiation of SMT(TP1)and subsequent to the completion of the SMT sessions(TP2).SMT was administered once every other day for 30 min per session,totally 14 treatment sessions over a span of 4 *** did not receive SMT treatment and underwent only one f MRI ***,participants in LDH group completed clinical questionnaires on pain using the Visual Analog Scale(VAS)and the Japanese Orthopedic Association(JOA)score,whereas HCs did not undergo clinical scale *** effects on the brain were jointly characterized using the amplitude of low-frequency fluctuations(ALFF)and regional homogeneity(Re Ho).Correlation analyses were conducted between specific brain regions and clinical ***:Following SMT treatment,pain symptoms in LDH patients were notably alleviated and accompanied by evident activation of effects in the *** comparison to TP1,TP2 exhibited the most significant increase in ALFF values for Temporal_Sup_R and the most notable decrease in ALFF values for Paracentral_Lobule_L(voxelwise P30;FDR correction).Additionally,the most substantial enhancement in Re Ho values was observed for the Cuneus_R,while the most prominent reduction was noted for the Olfactory_R(voxelwise P30;FDR correction).Moreover,a comparative analysis revealed that,in contrast to HCs,LDH patients at TP1 exhibited the most significant increase in ALFF values for Temporal_Pole_Sup_L and the most notable decrease in ALFF values for Frontal_Mid_L(voxelwise P30;FDR correction).Fur
The microscopic occurrence characteristics primarily constrain the enrichment and mobility of shale *** study collected the lacustrine shales from the Palaeogene Funing Formation in the Gaoyou Sag, Subei Basin. Conven...
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The microscopic occurrence characteristics primarily constrain the enrichment and mobility of shale *** study collected the lacustrine shales from the Palaeogene Funing Formation in the Gaoyou Sag, Subei Basin. Conventional and multistage Rock-Eval, scanning electron microscopy, and nuclear magnetic resonance(NMR) T1-T2were performed to analyze the contents and occurrence characteristics of shale oil. Low-temperature nitrogen adsorption-desorption(LTNA/D) experiments were conducted on the shales before and after extraction. The relationships between shale oil occurrence with organic matter and pore structures were then discussed. Predominantly, the shale oil in the Funing Formation is found within fractures, with secondary occurrences in interparticle pores linked to brittle minerals and sizeable intraparticle pores associated with clay minerals. The selected shales can be categorized into two types based on the nitrogen isotherms. Type A shales are characterized by high contents of felsic and calcareous minerals but low clay minerals, with larger TOC and shale oil values. Conversely, Type B shales are marked by abundant clay minerals but diminished TOC and shale oil contents. The lower BET specific surface area(SSA), larger average pore diameter, and simpler pore surfaces and pore structures lead to the Type A shales being more conducive to shale oil enrichment and mobility. Shale oil content is predominantly governed by the abundance of organic matter, while an overabundance of organic matter typically equates to a reduced ratio of free oil and diminished fluidity. The BET SSA, volumes of pores less than 25 and 100 nm at extracted state all correlate negatively with total and adsorbed oil contents but display no correlation with free oil, while they have positive relationships with capillary-bound ***, pore water is mainly saturated in micropores(<25 nm) and minipores(25-100 nm), as well as adsorbed oil, while free oil, i.e., bound and movable
To investigate the performance of utilizing the shape memory effect of SMA(Shape Memory Alloy)wire to generate recovery stress,this paper performed single heating recovery stress tests and reciprocating heating-coolin...
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To investigate the performance of utilizing the shape memory effect of SMA(Shape Memory Alloy)wire to generate recovery stress,this paper performed single heating recovery stress tests and reciprocating heating-cooling recovery stress tests on SMA wire under varying initial strain *** effects of various strains and different energized heating methods on the recovery stress of SMA wires were explored in the single heating *** SMA wire was strained from 2%to 8%initially,and two distinct heating approaches were employed:one using a large current interval for rapid heating and one using a small current interval for slower *** experimental outcomes reveal that during a single heating cycle,the temperature-recovery stress relationship of SMA wire exhibits three distinct stages:the martensite phase stage,the transition stage from martensite to austenite phase,and the austenite phase ***,the choice of heating method does not influence the maximum recovery stress value,and the correlation between initial strain and maximum recovery stress is predominantly ***,conducting the reciprocating temperature rise and fall performance test is important to better simulate the scenario in practical engineering where multiple recovery stress in SMA wires for structural *** this test,two temperature cycling methods were studied:interval rise and fall,as well as direct rise and *** the case of utilizing the interval temperature rise and fall method,it was observed that the recovery stress associated with cooling was significantly higher than that corresponding to heating at the same ***,the recovery stress was lower upon subsequent heating than that measured during the previous heating *** on the experimental results,a prediction model for the temperature-recovery stress relationship has been proposed to simplify numerical *** is hoped that an approximate temperaturerecovery stress curve can be
Near-eutectic Al-Si alloys are widely used in automotive manufacturing due to their superior wear resistance and high temperature *** of high Si content,the grain refinement of near-eutectic Al-Si alloy has been a pro...
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Near-eutectic Al-Si alloys are widely used in automotive manufacturing due to their superior wear resistance and high temperature *** of high Si content,the grain refinement of near-eutectic Al-Si alloy has been a problem for many *** this study,the effect of deep cryogenic treatment(DCT)on the microstructure and mechanical properties of Al-12Si-4Cu-2Ni-Mg alloy with addition of Al-Ti-C-B master alloy was fully *** show that the average grain size of the alloy is greatly reduced from 0.92 mm to 0.50 mm,and the eutectic Si and Al7Cu4Ni precipitates are spheroidized and refined in Al-12Si-4Cu-2Ni-Mg after DCT for 24 h and aging *** these changes of microstructures result in a significant increment of about 22.5%in elongation and a slight enhancement of about 6.8%in tensile ***,the refinement of microstructure also significantly improves the fatigue life of the alloy.
BACKGROUND Chronic hepatitis B often progresses silently toward hepatocellular carcinoma(HCC),a leading cause of mortality *** detection of HCC is crucial,yet *** To investigate the role of dynamic changes in alkaline...
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BACKGROUND Chronic hepatitis B often progresses silently toward hepatocellular carcinoma(HCC),a leading cause of mortality *** detection of HCC is crucial,yet *** To investigate the role of dynamic changes in alkaline phosphatase to prealbumin ratio(APR)in hepatitis B progression to *** Data from 4843 patients with hepatitis B(January 2015 to January 2024)were *** incidence rates in males and females were compared using the log-rank *** were evaluated using Kaplan–Meier *** Linear Mixed-Effects Model was applied to track the fluctuation of APR levels over ***,Joint Modeling of Longitudinal and Survival data was employed to investigate the temporal relationship between APR and HCC *** The incidence of HCC was higher in *** ensure the model’s normality assumption,this study applied a logarithmic transformation to APR,yielding *** levels were higher in females(t=5.26,P<0.01).A 1-unit increase in ratio correlated with a 2.005-fold higher risk of HCC in males(95%CI:1.653-2.431)and a 2.273-fold higher risk in females(95%CI:1.620-3.190).CONCLUSION Males are more prone to HCC,while females have higher APR *** no baseline APR link,rising APR indicates a higher HCC risk.
High strength steels exhibit superior mechanical properties due to the unique microstructure, which successfully solves the drawback of the inevitable strength-toughness trade-off that occurs in traditional alloys. He...
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High strength steels exhibit superior mechanical properties due to the unique microstructure, which successfully solves the drawback of the inevitable strength-toughness trade-off that occurs in traditional alloys. Here we investigated the effect of matrix and precipitates on mechanical properties of Cr-Ni-Mo-V/Nb steel after water quenching and tempering (150-500 degrees C). The results showed that the microstructure of the present steel is noticeably tuned by changing the tempering temperature. An excellent combination of strength (a yield strength of 1308 MPa with a total elongation of 8.2%) and toughness (Charpy V-notch impact toughness of 40.5 J/cm2) is obtained upon tempering at 200 degrees C. This is attributed to the lath martensite containing high dislocation density, the martensite-twin substructure, and the strengthening effects of the precipitated needle-like epsilon-carbides and spherical VC particles. The acicular epsilon-carbides are replaced by the rod-shaped Fe3C at the tempering temperature of 350 degrees C, resulting in the remarkable deterioration in strength, hardness, and elongation. Spheroidized carbides formed at a tempering temperature of 500 degrees C are beneficial to the enhancement of the elongation and toughness, but the strength decreases due to the matrix softening caused by the recovery of dislocation.
Electrochemical conversion of hypertoxic trivalent arsenic to value-added metallic arsenic can not only contribute to pollution abatement,but also resources reutilization,therefore being widely *** reduction of trival...
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Electrochemical conversion of hypertoxic trivalent arsenic to value-added metallic arsenic can not only contribute to pollution abatement,but also resources reutilization,therefore being widely *** reduction of trivalent arsenic as a promising way is widely ***,the high efficiency conversion is retarded by the sluggish reduction kinetics of AsO33−and fierce evolution of side products of both H_(2)and toxic AsH_(3).Herein,by using the sodium citrate as the additive,the current efficiency for metal arsenic production is increased greatly from 60%to 91%,with the accompanied evolution of hypertoxic AsH_(3)being restrained from 0.15 Nm^(3)/t_(As)to 0.022 Nm^(3)/t_(As),promising a high-efficiency and green *** electrochemical tests and electrode surface characterizations aswell as DFT calculations indicate that the added sodium citrate promotes both the diffusion of reactive AsO_(3)^(3−)towards the cathode and its subsequent adsorption on the Ti cathode,contributing to smoother reduction for generating metal arsenic,with the evolution of toxic AsH_(3)being hindered at the same *** results can provide new insights for the highefficiency and greener conversion of hypertoxic trivalent arsenic to value-added metallic arsenic.
ChatGPT is a powerful artificial intelligence(AI)language model that has demonstrated significant improvements in various natural language processing(NLP) tasks. However, like any technology, it presents potential sec...
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ChatGPT is a powerful artificial intelligence(AI)language model that has demonstrated significant improvements in various natural language processing(NLP) tasks. However, like any technology, it presents potential security risks that need to be carefully evaluated and addressed. In this survey, we provide an overview of the current state of research on security of using ChatGPT, with aspects of bias, disinformation, ethics, misuse,attacks and privacy. We review and discuss the literature on these topics and highlight open research questions and future *** this survey, we aim to contribute to the academic discourse on AI security, enriching the understanding of potential risks and mitigations. We anticipate that this survey will be valuable for various stakeholders involved in AI development and usage, including AI researchers, developers, policy makers, and end-users.
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