Enhancing Reliability via Checkpointing in Cloud Computing Systems

Cloud computing is becoming an important solution for providing scalable computing resources via Internet. Because there are tens of thousands of nodes in data center, the probability of server failures is nontrivial. Therefore, it is a critical challenge to guarantee the service reliability. Fault-tolerance strategies, such as checkpoint, are commonly employed. Because of the failure of the edge switches, the checkpoint image may become inaccessible. Therefore, current checkpoint-based fault tolerance method cannot achieve the best effect. In this paper, we propose an optimal checkpoint method with edge switch failure-aware. The edge switch failure-aware checkpoint method includes two algorithms. The first algorithm employs the data center topology and communication characteristic for checkpoint image storage server selection. The second algorithm employs the checkpoint image storage characteristic as well as the data center topology to select the recovery server. Simulation experiments are performed to demonstrate the effectiveness of the proposed method.

Application of zebrafish in the study of the gut microbiome

Zebrafish(D anio rerio)have attracted much attention over the past decade as a reliable model for gut microbiome research.Owing to their low cost,strong genetic and development coherence,efficient preparation of germ-f ree(GF)larvae,availability in high-t hroughput chemical screening,and fitness for intravital imaging in vivo,zebrafish have been extensively used to investigate microbiome-h ost interactions and evaluate the toxicity of environmental pollutants.In this review,the advantages and disadvantages of zebrafish for studying the role of the gut microbiome compared with warm-b looded animal models are first summarized.Then,the roles of zebrafish gut microbiome on host development,metabolic pathways,gut-b rain axis,and immune disorders and responses are addressed.Furthermore,their applications for the toxicological assessment of aquatic environmental pollutants and exploration of the molecular mechanism of pathogen infections are reviewed.We highlight the great potential of the zebrafish model for developing probiotics for xenobiotic detoxification,resistance against bacterial infection,and disease prevention and cure.Overall,the zebrafish model promises a brighter future for gut microbiome research.

Process optimization and mechanism study of ionic liquid-based mixed amine biphasic solvents for CO_(2) capture in biogas upgrading procedure

This study focused on enhancing the efficiency of methane upgrading and reducing energy consumption in the biogas upgrading process through the use of biphasic solvents.An aqueous-based biphasic solvent,comprising methyl monoethanolamine(MMEA),N-methyldiethanolamine(MDEA),and 1-butyl-3-methylimidazolium tetrafluoroborate(ItFB),was meticulously prepared.The biogas upgrading effect,regeneration efficiency,regeneration energy consumption,economic viability,selectivity,and phase separation characteristics of this absorbent were systematically analyzed.Various parameters,including different inlet flow rates,stirring rate,methane inlet concentrations,reaction temperatures,and amine mixing ratios,were adjusted to investigate their impact.A comprehensive evaluation was conducted on the biogas upgrading effect and substance migration trends of the biphasic solvent.Optimal process parameters were determined,demonstrating the favorable impact of the biphasic solvent on biogas upgrading.The upgraded gas achieved a methane purity exceeding 96%,and the regeneration energy consumption decreased by 44.27% compared to 30 wt.%MEA,resulting in a more than 50% improvement in economic efficiency.The interaction between the ionic liquid and carbamate facilitated the phase separation process,with carbon enrichment after separation exceeding 95%.This enhancement significantly contributed to the improvement of regeneration energy consumption.The study thus concludes that biphasic solvents,exemplified by the described aqueous-based solution,offer a promising avenue for effective biogas upgrading with notable advancements in economic and energy efficiency.

Integrated Route Planning and Resource Allocation for Connected Vehicles

Intelligent and connected vehicles have leveraged edge computing paradigm to enhance their environment comprehension and behavior planning capabilities.As the quantity of intelligent vehicles and the demand for edge computing are increasing rapidly,it becomes critical to efficiently orchestrate the communication and computation resources on edge clouds.Existing methods usually perform resource allocation in a fairly effective but still reactive manner,which is subject to the capacity of nearby edge clouds.To deal with the contradiction between the spatiotemporally varying demands for edge computing and the fixed edge cloud capacity,we proactively balance the edge computing demands across edge clouds by appropriate route planning.In this paper,route planning and resource allocation are jointly optimized to enhance intelligent driving.We propose a multi-scale decentralized optimization method to deal with the curse of dimensionality.In large-scale optimization,backpressure algorithm is used to conduct route planning and load balancing across edge clouds.In small-scale optimization,game-theoretic multi-agent learning is exploited to perform regional resource allocation.The experimental results show that the proposed algorithm outperforms the baseline algorithms which optimize route planning and resource allocation separately.

Bus Arrival Time Prediction Based on Mixed Model

How to predict the bus arrival time accurately is a crucial problem to be solved in Internet of Vehicle. Existed methods cannot solve the problem effectively for ignoring the traffic delay jitter. In this paper,a three-stage mixed model is proposed for bus arrival time prediction. The first stage is pattern training. In this stage,the traffic delay jitter patterns(TDJP)are mined by K nearest neighbor and K-means in the historical traffic time data. The second stage is the single-step prediction,which is based on real-time adjusted Kalman filter with a modification of historical TDJP. In the third stage,as the influence of historical law is increasing in long distance prediction,we combine the single-step prediction dynamically with Markov historical transfer model to conduct the multi-step prediction. The experimental results show that the proposed single-step prediction model performs better in accuracy and efficiency than short-term traffic flow prediction and dynamic Kalman filter. The multi-step prediction provides a higher level veracity and reliability in travel time forecasting than short-term traffic flow and historical traffic pattern prediction models.

Porous silica synthesis out of coal fly ash with no residue generation and complete silicon separation

Ordered mesoporous silica materials exhibit enormous potential in industrial production.Since coal fly ash(CFA)is abundant in Si,it has become a green and promising way to utilize CFA by synthesizing porous silica materials.However,the stable crystalline structure of CFA limits the extraction of Si,and the residue is generated during the process of extracting Si.In this work,we proposed a no-residue method to synthesize ordered mesoporous silica out of CFA.Sodium carbonate(Na_(2)CO_(3))was used to reconstruct the crystals of the CFA,and the calcined mixture then directly reacted with the precipitators.This method combined the process of Si extraction and porous material synthesis.In this method,no residue was generated and the silicon in both amorphous and crystalline phases of CFA was fully utilized.By this method,the extraction efficiency of Si was increased from 31.75%to nearly 100%.The as-synthesized mesoporous silica had a highly-ordered pore structure with a space group of la-3d,a surface area of 663.87 m^(2)/g,a pore volume of 0.41 cm^(3)/g,and an average pore diameter of 2.73 nm.The mechanism of crystalline transformation and material structure formation were systematically studied.This method provides a new idea to dispose of CFA and synthesize porous silica materials.

Aulr@InGaN纳米组装体人工光合成C_(2+)燃料联产H_(2)O_(2)

以太阳光为能量输入,二氧化碳(CO_(2))和水(H_(2)O)为原料,经人工光合作用合成可再生燃料和化学品,为解决能源危机和气候变化等核心挑战提供了一条有潜力的策略^([1]).与电催化、热催化和生物催化等固碳方式相比,光催化具有配置简单、成本低廉或环境友好等优点.然而,在无牺牲剂和无外加热能或者电能的条件下.

光驱动Rh/InGaN_(1-x)O_(x)纳米组装体甲烷干重整制合成气

Light-driven dry reforming of methane toward syngas presents a proper solution for alleviating climate change and for the sustainable supply of transportation fuels and chemicals.Herein,Rh/InGaN_(1-x)O_(x) nanowires supported by silicon wafer are explored as an ideal platform for loading Rh nanoparticles,thus assembling a new nanoarchitecture for this grand topic.In combination with the remarkable photothermal synergy,the O atoms in Rh/InGaN_(1-x)O_(x) can significantly lower the apparent activation energy of dry reforming of methane from 2.96 eV downward to 1.70 eV.The as-designed Rh/InGaN_(1-x)O_(x) NWs nanoarchitecture thus demonstrates a measurable syngas evolution rate of 180.9 mmol g_(cat)^(-1) h^(-1) with a marked selectivity of 96.3% under concentrated light illumination of 6 W cm^(-2).What is more,a high turnover number(TON)of 4182 mol syngas per mole Rh has been realized after six reuse cycles without obvious activity degradation.The correlative 18O isotope labeling experiments,in-situ irradiated X-ray photoelectron spectroscopy(ISI-XPS)and in-situ diffuse reflectance Fourier transform infrared spectroscopy characterizations,as well as density functional theory calculations reveal that under light illumination,Rh/InGaN_(1-x)O_(x) NWs facilitate releasing^(*)CH_(3) and H^(+)from CH_(4) by holes,followed by H_(2) evolution from H^(+)reduction with electrons.Subsequently,the O atoms in Rh/InGaN_(1-x)O_(x) can directly participate in CO generation by reacting with the ^(*)C species from CH_(4) dehydrogenation and contributes to the coke elimination,in concurrent formation of O vacancies.The resultant O vacancies are then replenished by CO_(2),showing an ideal chemical loop.This work presents a green strategy for syngas production via light-driven dry reforming of methane.

Prospects of sea launches for Chinese cryogenic liquid-fueled medium-lift launch vehicles

This paper introduces the sea-launch technology of a cryogenic liquid-fueled medium-lift rocket.It first reviews the current state of sea launch technology,and then gives a brief introduction of China’s New Generation Medium-lift Launch Vehicle(NGMLV).The innovations in the NGMVL,such as responsive test and launch control,a H3 launch model,and unmanned operations,provide convenience for sea launches.Based on these innovations,this paper proposes a sea launch scheme,including the system configuration,test and launch processes,and an improved adaptive design for the rocket.Then,the launch platform is discussed in detail,which integrates the functions of sea transportation,assembly and test,as well as technical and launch areas.The layout and function divisions,fluid filling,gas supply and distribution systems,and lossless storage technology of LH2 are described in order.This breakthrough in sea launch technology will enable China to launch medium and large satellites and constellations‘both on land and sea’,especially into low-inclination Low-Earth Orbits(LEOs),and it allows China to remain competitive in the fast-paced space industry.

GaN nanowires/Si photocathodes for CO_(2) reduction towards solar fuels and chemicals: advances, challenges, and prospects

Photoelectrocatalytic(PEC)production of fuels and chemicals by using solar energy,water,and CO_(2) paves a promising avenue toward carbon neutrality.Over the past decades,for accelerating this process,a variety of photocathodes have been explored.Among them,the hybrid of GaN nanowires(NWs)and planar silicon has appeared as a disruptive platform for this grand topic,owing to their distinctive structural,optoelectronic,and catalytic properties.This review illustrates the most recent advances in GaN NWs/Si-based photocathodes for CO_(2) reduction reactions powered by simulated sunlight,beginning with a discussion of the critical requirements and fundamental challenges of PEC CO_(2) reduction.The characteristics of GaN NWs/Si are then discussed,showing its great potential in precisely controlling the behavior of photons,charges,and chemical species.As the focus of this review,the progress on the PEC CO_(2) reduction reactions toward different products over GaN NWs/Si-based photocathodes is highlighted.In the end,the challenges and prospects of GaN NWs/Si-based photocathodes for the practical synthesis of solarfuels and chemicals are proposed.

Roles and Molecular Mechanisms of Biomarkers in Hepatocellular Carcinoma with Microvascular Invasion: A Review

Hepatocellular carcinoma(HCC)being a leading cause of cancer-related death,has high associated mortality and recurrence rates.It has been of great necessity and urgency to find effective HCC diagnosis and treatment measures.Studies have shown that microvascular invasion(MVI)is an independent risk factor for poor prognosis after hepatectomy.The abnormal expression of biomacromolecules such as circ-RNAs,lncRNAs,STIP1,and PD-L1 in HCC patients is strongly correlated with MVI.Deregulation of several markers mentioned in this review affects the proliferation,invasion,metastasis,EMT,and anti-apoptotic processes of HCC cells through multiple complex mechanisms.Therefore,these biomarkers may have an important clinical role and serve as promising interventional targets for HCC.In this review,we provide a comprehensive overview on the functions and regulatory mechanisms of MVI-related biomarkers in HCC.

Architecture and key technologies for Internet of Vehicles:a survey

In recent years,IoV(Internet of Vehicles)has become one of the most active research elds in network and intelligent transportation system.As an open converged network,IoV plays an important role in solving various driving and traffc problems by advanced information and communications technology.We review the existing notions of IoV from di erent perspectives.Then,we provide our notion from a network point of view and propose a novel IoV architecture with four layers.Particularly,a novel layer named coordinative computing control layer is separated from the application layer.The novel layer is used for solving the coordinative computing and control problems for human-vehicle-environment.After summarizing the key technologies in IoV architecture,we construct a VV(Virtual Vehicle),which is an integrated image of driver and vehicle in networks.VVs can interact with each other in cyber space by providing traffc service and sharing sensing data coordinately,which can solve the communication bottleneck in physical space.Finally,an extended IoV architecture based on VVs is proposed.