Machine Learning Based Resource Allocation of Cloud Computing in Auction

Resource allocation in auctions is a challenging problem for cloud computing.However,the resource allocation problem is NP-hard and cannot be solved in polynomial time.The existing studies mainly use approximate algorithms such as PTAS or heuristic algorithms to determine a feasible solution;however,these algorithms have the disadvantages of low computational efficiency or low allocate accuracy.In this paper,we use the classification of machine learning to model and analyze the multi-dimensional cloud resource allocation problem and propose two resource allocation prediction algorithms based on linear and logistic regressions.By learning a small-scale training set,the prediction model can guarantee that the social welfare,allocation accuracy,and resource utilization in the feasible solution are very close to those of the optimal allocation solution.The experimental results show that the proposed scheme has good effect on resource allocation in cloud computing.

Position Optimization for Mobile Relay Communications with Constrained Energy over a Whole Horizontal Plane

This paper concerns the position optimization problem of a mobile relay over a whole horizontal plane.This problem is important because the position of a mobile relay directly affects the end-to-end performance,e.g.,reliability,connectivity,and data rate.In this paper,we propose a new position optimization scheme of a mobile relay over a whole horizontal plane based on the one-bit feedback information from the destination node,which improves the performance over the prior scheme whose position of the mobile relay is optimized over a fixed orbit.In the proposed scheme,the mobile relay is equipped with merely one single onboard antenna.Moreover,no prior information about the positions of both the source node and the destination node is required.Thus,the proposed scheme can work at low network resources scenario,which is particularly suitable for mobile relay communication with constrained energy,e.g.,the communications in a disaster area where the infrastructure is heavily damaged,volcano monitoring,and wireless powered communication networking.According to the characteristics of the proposed scheme,we further design two heuristic implementations to calculate the optimal position of a mobile relay over a whole horizontal plane.The first implementation has better steady performance whereas the second implementation has better convergence speed.We implement the proposed scheme and conduct an extensive performance comparison between the proposed scheme and prior schemes to verify the advantages of the proposed scheme.

Lactobacillus species shift in distal esophagus of high-fat-diet-fed rats

AIM： To analyze the microbiota shift in the dista esophagus of Sprague-Dawley rats fed a high-fat diet. METHODS： Twenty Sprague-Dawley rats were divided into high-fat diet and normal control groups of 10 rats each. The composition of microbiota in the mucosa from the distal esophagus was analyzed based on se- lective culture. A variety of Lactobacillus species were identified by molecular biological techniques. Bacterial DNA from Lactobacillus colonies was extracted, and 165 rDNA was amplified by PCR using bacterial uni- versal primers. The amplified 16S rDNA products were separated by denaturing gradient gel electrophoresis （DGGE）. Every single band was purified from the gel and sent to be sequenced. RESULTS： Based on mucosal bacterial culturing in the distal esophagus, Staphylococcus aureus was absent, and total anaerobes and Lactobacillus species were de- creased significantly in the high-fat diet group compared with the normal control group （P 〈 0.01）. Detailed DGGE analysis on the composition of Lactobacillus species in the distal esophagus revealed that Lactobacillus crispa- tus, Lactobacillus gasseri （L. gasser/] and Lactobacillus reuteri （L. reuterl] comprised the Lactobacillus species in the high-fat diet group, while the composition of Lactobacillus species in the normal control group consisted of L. gasseri, Lactobacillus jensenii and L. reuteri. CONCLUSION： High-fat diet led to a mucosal micro- flora shift in the distal esophagus in rats, especially the composition of Lactobacillus species.

Improving the Covertness in the Physical-Layer Authentication

A well-designed Physical-Layer Authentication(PLA)scheme should consider three properties:covertness,robustness,and security.However,the three properties always cause some dilemmas,e.g.,higher covertness leading to lower robustness.This paper concerns the problem of improving the covertness without sacrificing the robustness.This problem is important because of the following reasons:reducing the errors in recovered source message,improving the security,and ease of constructing a multi-factor authentication system.In this paper,we propose three covert PLA schemes to address the problem.In the first scheme,we improve the covertness by reducing the modification ratio on the source message based on an encoding mechanism.In the second scheme,we improve the covertness by optimizing the superimposing angle,which maximizes the minimum distance between the tagged symbols and the boundary line of the demodulation decision for the source message.In the third scheme,referred to as the hybrid scheme,we further improve the covertness by jointly using the advantages of both the above two schemes.Our experimental results show that when the SNR at a legitimate receiver is 25 dB,as compared with the prior scheme,the first scheme improves the covertness by 17:74%,the second scheme improves the covertness by 28:79%,and the third scheme improves the covertness by 32:09%,while they have similar robustness as Received:Aug.07,2020 Revised:Sep.08,2020 Editor:Nanrun Zhou that of the prior scheme.

Resilience enhancement strategy using microgrids in distribution network

We propose a restoration strategy using microgrids for restoring power supply to critical loads after an extreme event and thereby enhancing the resilience of the distribution power grid. The limited capacities of distributed generators(DGs) within the microgrids and those of intermittent energy sources such as wind and photovoltaic power are considered. An enhanced strategy model of the distribution network is established for maximizing the power supply to critical loads. Firstly, the importance of the load is quantified by using the analytic hierarchy process(AHP) and the model of the microgrid output is further improved. In the demand response mechanism, an interruptible load is used to suppress the fluctuation in the distributed power output. Secondly, piecewise linearization method is applied to address the power flow constraints. Then, the resilience enhancement model of the distribution network is transformed into a mixed integer quadratic programming problem. The CPLEX solver is adopted to solve the above problem on the MATLAB platform. Finally, the proposed method is verified by applying it to practical scenarios.

A New Azafluorenone Alkaloid from Alphonsea Monogyma

A new azafluorenone (onychine) alkaloid, 6,7-dimethoxy-5-hydroxy-onychine, was isolated from the stem and branch of Alphonsea monogyma. Its structure was established mainly on the basis of spectral analysis.

一种基于Hadoop集群的自然语言处理平台实现方案

本文提出一种基于Hadoop集群的自然语言处理平台实现方案,通过网页收集用户需求和数据,自动调用集群进行处理,返回处理结果。且支持运行第三方开发者编写的Mapreduce插件,平台易扩展。通过实验验证,方案能实现及时响应用户需求,准确调用相关程序,并返回处理结果。

A New Oxoaporphine Alkaloid from Alphonsea Mollis Dun.

A new oxoaporphine alkaloid, 1,2-methylene-dioxy-8-hydroxy-5- oxoaporphine, was isolated from the stem barks of Alphonsea mollis . Its structure was established on the basis of spectral analysis and chemical correlation.

TEUPONXN: A NEO-CLERODANE DITERPENE FROM TEUCRIUM JAPONICUM

A nco—clcrodane diterpcne, teuponin, was isolated from the aerial parts of Teucrium japonicum. Its structure was established as (12S)—19—nor—neo—clcroda— 15a—hydroxy—4,13-diene— 16,15;18,6β;20,12-triolide by spcctroscopic means. The absolute configuration was determined by X—ray diffraction analysis and CD spectrum.

A New Azafluorenone Alkaloid from Alphonsea monogrma

A new azafluorenone (onychine) alkaloid. 6.7-dimethoxy-5-hydroxy onychine N-oxide. was isolated from the stem and branch of Alphonsea monogyma. Its structure was established on the basis of spectral and chemical analysis.

Utility-Based Node Cooperation Mechanism in Wireless Sensor Networks

In wireless sensor networks, due to the energy and resource constraints, nodes may be unwilling to forward packets for their neighbors. This can render severe deteriorations in the network performance and malfunctions of the system. To tackle such selfish behaviors and enhance the cooperation among sensors, based on reputation and energy consumption of each node, we present a utility function to punish the malicious nodes and encourage cooperation among nodes. Specifically, we firstly give a mixed strategy Nash equilibrium solution for the two nodes. Then we extend the model to multi-nodes scenario. With the unity function, each sensor’s reputation is evaluated according to its degree of cooperation. The extensive simulation results have shown the effectiveness of the mechanism, in that the cooperative behaviors are encouraged, which can ensure the normal functioning of the network system.

An MDP Based Energy Efficient Transmission Policy for Wireless Terminals

In wireless network, terminals are usually energy constrained. In order to extend the lifetime of the terminal, the limited energy must be utilized in an efficient manner. In this paper, under the constant transmission power scenario, we propose an Energy Efficient Transmission Policy (EETP) which is derived by using Markov Decision Process (MDP). The simulation results show that compared with the Threshold Transmission Policy (TTP), the proposed policy can reduce the energy consumption significantly, while satisfying the performance demand at the same time.

细胞外液黏度:细胞生物学中一个新的物理信号

细胞行为受到微环境中物理信号的调控,其中细胞外液(ECF)黏度作为一个重要的物理刺激,相关研究较少.近期研究表明:ECF黏度在调控与心血管相关疾病、炎症性疾病和癌症等多种疾病相关的细胞病理学过程中起关键作用.

Decoding the chromatin accessibility in Andrographis paniculata genome,a case study of genome-wide investigation of the cis-regulatory elements in medicinal plants

To the Editor:Medicinal plants have the ability to synthesize a large number of pharmaceutical metabolites,the production and regulation of which are influenced by both intrinsic signals(e.g.,the spatial and temporal stage)and extrinsic environmental conditions(e.g.,temperature,light availability,and water availability)^(1).According to the Encyclopedia of DNA Elements(ENCODE)project^(2),accessible chromatin regions(ACRs)served essential roles in maintaining the genome architecture and gene regulation in both mammals and plants.Nowadays,identifying ACRs within medicinal plant genomes remains a challenge,as genomic sequences have been determined for numerous species yet the characterization of such functional elements lags.In this study,we selected Andrographis paniculata(APA)^(3) as a model system to map ACRs genome-wide by the assay for transposase-accessible chromatin with sequencing(ATAC-seq)method.We aimed to uncover the genomic features of ACRs as well as their association with the expression of genes involved in secondary metabolite biosynthesis(e.g.,andrographolide)within medicinal plants(Supporting Information Fig.S1).

Imprints of ultralight axions on the gravitational wave and pulsar timing measurement

The axion or axion-like particle motivated from a natural solution of strong CP problem or string theory is a promising dark matter candidate.We study the new observational effects of ultralight axion-like particles by the space-borne gravitational wave detector and the radio telescope.Taking the neutron star-black hole binary as an example,we demonstrate that the gravitational waveform could be obviously modified by the slow depletion of the axion cloud around the black hole formed through the superradiance process.We compare these new effects on the binary with the well-studied effects from dynamical friction with dark matter and dipole radiation in model-independent ways.Finally,we discuss the constraints from LIGO/Virgo and study the detectability of the ultralight axion particles at LISA and TianQin.

Hybrid Modulation Strategy with Voltage Balancing Control for Four-level Neutral-point Clamped Converters

Capacitor voltage imbalance in four-level(4L)neutral-point clamped(NPC)converters is a direct factor hindering their application.In particular,when they are applied in motor drives,space vector pulse-width modulation(SVPWM)is a more popular scheme,but conventional 4L SVPWM cannot achieve the voltage balancing control of DC-link capacitors,is complex to implement,and requires costly computation.A hybrid modulation method with capacitor voltage-balancing control for 4L NPC converters is proposed.The proposed method is achieved using three-level(3L)SVPWM and two-level(2L)carrier-based pulse-width modulation(CPWM)based on the concept of"4L=3L+2L".Thus,it can be easily implemented on a digital chip because the modulation process is nearly identical to that of 3L SVPWM without the more cumbersome 4L SVPWM algorithm.Meanwhile,any proven optimization scheme of 3L SVPWM can be directly applied to the proposed method to further improve performance.Simulation and experimental results for a 4L active NPC converter demonstrate the effectiveness of the proposed method.

Two-stage stochastic-robust model for the self-scheduling problem of an aggregator participating in energy and reserve markets

This paper addresses a two-stage stochastic-robust model for the day-ahead self-scheduling problem of an aggrega-tor considering uncertainties.The aggregator,which integrates power and capacity of small-scale prosumers and flex-ible community-owned devices,trades electric energy in the day-ahead(DAM)and real-time energy markets(RTM),and trades reserve capacity and deployment in the reserve capacity(RCM)and reserve deployment markets(RDM).The ability of the aggregator providing reserve service is constrained by the regulations of reserve market rules,including minimum offer/bid size and minimum delivery duration.A combination approach of stochastic program-ming(SP)and robust optimization(RO)is used to model different kinds of uncertainties,including those of market price,power/demand and reserve deployment.The risk management of the aggregator is considered through con-ditional value at risk(CVaR)and fluctuation intervals of the uncertain parameters.Case studies numerically show the economic revenue and the energy-reserve schedule of the aggregator with participation in different markets,reserve regulations,and risk preferences.

Fungal diversity notes 1611-1716: taxonomic and phylogenetic contributions on fungal genera and species emphasis in south China

This article is the 15th contribution in the Fungal Diversity Notes series,wherein 115 taxa from three phyla,nine classes,28 orders,48 families,and 64 genera are treated.Fungal taxa described and illustrated in the present study include a new family,five new genera,61 new species,five new combinations,one synonym,one new variety and 31 records on new hosts or new geographical distributions.Ageratinicolaceae fam.nov.is introduced and accommodated in Pleosporales.The new genera introduced in this study are Ageratinicola,Kevinia,Pseudomultiseptospora(Parabambusicolaceae),Marasmiellomycena,and Vizzinia(Porotheleaceae).Newly described species are Abrothallus altoandinus,Ageratinicola kunmingensis,Allocryptovalsa aceris,Allophoma yuccae,Apiospora cannae,A.elliptica,A.pallidesporae,Boeremia wisteriae,Calycina papaeana,Clypeo-coccum lichenostigmoides,Coniochaeta riskali-shoyakubovii,Cryphonectria kunmingensis,Diaporthe angustiapiculata,D.campylandrae,D.longipapillata,Diatrypella guangdongense,Dothiorella franceschinii,Endocalyx phoenicis,Epicoc-cum terminosporum,Fulvifomes karaiensis,F.pannaensis,Ganoderma ghatensis,Hysterobrevium baoshanense,Inocybe avellaneorosea,I.lucida,Jahnula oblonga,Kevinia lignicola,Kirschsteiniothelia guangdongensis,Laboulbenia caprina,L.clavulata,L.cobiae,L.cosmodisci,L.nilotica,L.omalii,L.robusta,L.similis,L.stigmatophora,Laccaria rubriporus,Lasiodiplodia morindae,Lyophyllum agnijum,Marasmiellomycena pseudoomphaliiformis,Melomastia beihaiensis,Nemania guangdongensis,Nigrograna thailandica,Nigrospora ficuum,Oxydothis chinensis,O.yunnanensis,Petriella thailandica,Phaeoacremonium chinensis,Phialocephala chinensis,Phytophthora debattistii,Polyplosphaeria nigrospora,Pronectria loweniae,Seriascoma acutispora,Setoseptoria bambusae,Stictis anomianthi,Tarzetta tibetensis,Tarzetta urceolata,Tetraploa obpyriformis,Trichoglossum beninense,and Tricoderma pyrrosiae.We provide an emendation for Urnula ailaoshanensis Agaricus duplocingulatoides var.brevisporus introduced as a new variety based on morphology and phylogeny.

Power Flow Calculation for VSC-based AC/DC Hybrid Systems Based on Fast and Flexible Holomorphic Embedding

The power flow(PF)calculation for AC/DC hybrid systems based on voltage source converter(VSC)plays a crucial role in the operational analysis of the new energy system.The fast and flexible holomorphic embedding(FFHE)PF method,with its non-iterative format founded on complex analysis theory,exhibits superior numerical performance compared with traditional iterative methods.This paper aims to extend the FFHE method to the PF problem in the VSC-based AC/DC hybrid system.To form the AC/DC FFHE PF method,an AC/DC FFHE model with its solution scheme and a sequential AC/DC PF calculation framework are proposed.The AC/DC FFHE model is established with a more flexible form to incorporate multiple control strategies of VSC while preserving the constructive and deterministic properties of original FFHE to reliably obtain operable AC/DC solutions from various initializations.A solution scheme for the proposed model is provided with specific recursive solution processes and accelerated Padéapproximant.To achieve the overall convergence of AC/DC PF,the AC/DC FFHE model is integrated into the sequential calculation framework with well-designed data exchange and control mode switching mechanisms.The proposed method demonstrates significant efficiency improvements,especially in handling scenarios involving control mode switching and multiple recalculations.In numerical tests,the superiority of the proposed method is confirmed through comparisons of accuracy and efficiency with existing methods,as well as the impact analyses of different initializations.

Beyond clinical trials:CDK4/6 inhibitor efficacy predictors and nomogram model from real‐world evidence in metastatic breast cancer

Background:CDK4/6 inhibitors(CDK4/6i)have shown promising results in the treatment of hormone receptor‐positive(HR+)metastatic breast cancer(MBC)when combined with endocrine therapy(ET).It is crucial to evaluate the actual effectiveness and safety of CDK4/6i in clinical practice,as well as to analyze the factors that can predict their outcomes.Methods:Patients with HR+MBC who received CDK4/6i‐based therapy between May 2016 and May 2023 at Hunan Cancer Hospital were evaluated for progression‐free survival(PFS).Adverse reactions were assessed based on the National Cancer Institute Common Toxicity Criteria(version 5.0).Results:This study included 344 patients,with a median PFS(mPFS)of 12.8 months(range:10.4–15.2 months).After adjustment,Cox multivariate regression analysis revealed that visceral metastasis(specifically liver and brain metastases),Eastern Cooperative Oncology Group Performance Status(ECOG PS)≥1,estrogen receptor≤80%,progesterone receptor≤10%,Ki‐67>30%,and treatment in later stages were significant factors associated with reduced PFS.Based on this,we created a prognostic nomogram and validated its performance,obtaining a C‐index of 0.714(95%confidence interval:0.640–0.787)as well as reliable calibration and clinical impact.The mPFS of CDK4/6i rechallenge was 7.7 months;for patients who initially discontinued CDK4/6i for reasons other than disease progression,CDK4/6i rechallenge still provided a mPFS of 11.4 months.The tolerability and safety of combining CDK4/6is with ET were manageable.Adverse events led to treatment discontinuation in 3.8%of patients.Neutropenia(29.1%),leukopenia(13.7%),and anemia(4.1%)were the primary grade 3/4 adverse reactions.Conclusions:This real‐world study highlights the ample efficacy and reasonable safety of combined CDK4/6i and ET in patients with HR+MBC.Individualized treatment decisions and ongoing safety monitoring are important to optimize the therapeutic benefit of CDK4/6i treatment.