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基于动态服务缓存辅助的任务卸载方法

计算机应用 2024年第5期44卷 1493-1500页

作者：张俊娜王欣新李天泽赵晓焱袁培燕河南师范大学计算机与信息工程学院河南新乡453007

针对服务缓存和任务卸载联合优化中,由于缺乏对用户服务请求多样性和动态性的综合考虑而导致的用户体验质量降低问题,提出一种基于动态服务缓存辅助的任务卸载方法。首先,针对边缘服务器执行缓存服务动作空间较大的问题,重新定义了动作... 详细信息

针对服务缓存和任务卸载联合优化中,由于缺乏对用户服务请求多样性和动态性的综合考虑而导致的用户体验质量降低问题,提出一种基于动态服务缓存辅助的任务卸载方法。首先,针对边缘服务器执行缓存服务动作空间较大的问题,重新定义了动作,并筛选出最优的动作集合以提高算法训练的效率;其次,设计一种改进的多智能体Q-Learning算法学习最优的服务缓存策略;再次,将任务卸载问题转换为凸优化问题,利用凸优化工具获得最优解;最后,利用拉格朗日对偶法求得最优的计算资源分配策略。为了验证所提方法的有效性,基于真实数据集进行了充分的实验。实验结果表明,对比Q-Learning、双层深度Q网络(D2QN)以及多智能体深度确定性策略梯度(MADDPG)方法,所提方法的响应时间分别降低了8.5%、11.8%和12.6%,平均体验质量分别提高了1.5%、2.7%和4.3%。

关键词：边缘计算动态服务缓存任务卸载计算资源分配服务多样性

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基于Copula函数与多目标进化算法的负荷区间预测

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电气技术 2024年第6期25卷 24-30页

作者：李智轩李嘉丰叶晓华熊显智李天泽西安西电电力系统有限公司西安710076

与点预测相比,负荷区间预测可提供预测上界与下界,更有助于电力系统的稳定运行。针对未充分利用相邻负荷序列之间的相关关系而导致预测精度较低的问题,提出一种基于Copula函数与分解的多目标进化算法(MOEA/D)的负荷区间预测方法。该方... 详细信息

与点预测相比,负荷区间预测可提供预测上界与下界,更有助于电力系统的稳定运行。针对未充分利用相邻负荷序列之间的相关关系而导致预测精度较低的问题,提出一种基于Copula函数与分解的多目标进化算法(MOEA/D)的负荷区间预测方法。该方法通过建立Copula函数,挖掘相邻负荷序列之间的相关性,利用MOEA/D寻找Pareto最优解集,并通过熵权法与优劣解距离法(TOPSIS),得到最优的预测模型参数与预测结果。最后,将该方法应用于某地区的负荷预测,并与常用的区间预测方法进行对比,结果表明该方法具有更好的预测效果。

关键词：负荷预测 Copula函数区间预测多目标优化算法

Artemdubinoids A-N:novel sesquiterpenoids with antihepatoma cytotoxicity from Artemisia dubia

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Chinese Journal of Natural Medicines 2023年第12期21卷 902-915页

作者： GAO Zhen li tianze MA Yunbao HUANG Xiaoyan GENG Changan ZHANG Xuemei CHEN Jijun State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyChinese Academy of SciencesKunming 650201China University of Chinese Academy of Sciences Beijing 100049China

In pursuit of effective agents for hepatocellular carcinoma derived from the Artemisia species,this study built upon initial findings that an ethanol(EtOH)extract and ethyl acetate(EtOAc)fraction of the aerial parts of Artemisia dubia *** *** cytotoxicity against HepG2 cells with inhibitory rates of 57.1%and 84.2%(100μg·mL−1),*** by bioactivity,fourteen previously unidentified sesquiterpenes,artemdubinoids A–N(1–14),were isolated from the EtOAc *** structural elucidation was achieved through comprehensive spectroscopic analyses and corroborated by the comparison between the experimental and calculated ECD *** crystal X-ray diffraction provided definitive structure confirmation for artemdubinoids A,D,F,and *** A and B(1–2)represented unique sesquiterpenes featuring a 6/5-fused bicyclic carbon scaffold,and their putative biosynthetic pathways were discussed;artemdubinoid C(3)was a novel guaianolide derivative that might be formed by the[4+2]Diels–Alder reaction;artemdubinoids D and E(4–5)were rare 1,10-seco-guaianolides;artemdubinoids F–K(6–11)were chlorinecontaining *** compounds exhibited cytotoxicity against three human hepatoma cell lines(HepG2,Huh7,and SKHep-1)with half-maximal inhibitory concentration(IC50)values spanning 7.5−82.5μmol·L^(−1).Artemdubinoid M(13)exhibited the most active cytotoxicity with IC50 values of 14.5,7.5 and 8.9μmol·L^(−1)against the HepG2,Huh7,and SK-Hep-1 cell lines,respectively,which were equivalent to the positive control,sorafenib.

关键词： Artemdubinoids A-N Artemisia dubia Sesquiterpenoids Antihepatoma activity

Supplementation of alanine improves biomass accumulation and lipid production of Chlorella pyrenoidosa by increasing the respiratory and metabolic processes

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Journal of Oceanology and limnology 2024年第2期42卷 570-579页

作者： Yongfu li tianze ZHAO Wei SUN Ruiwen GAO Guangyuan MA Jiangsu Province Engineering Research Center for Marine Bioresources Sustainable Utilization Key Laboratory of Marine Hazards ForecastingMinistry of Natural ResourcesHohai UniversityNanjing 210098China College of Oceanography Hohai UniversityNanjing 210098China Jiangsu Innovation Center of Marine Bioresources Jiangsu Coast Development Group Co.Ltd.Nanjing 210019China

The function of exogenous alanine(Ala)in regulating biomass accumulation,lipid production,photosynthesis,and respiration in Chlorella pyrenoidosa was *** shows that the supplementation of Ala increased *** biomass and lipid production in an 8-d batch *** concentration of 10 mmol/L of Ala was optimum and increased the microalgal cell biomass and lipid content by 39.3%and 21.4%,respectively,compared with that in the control(0-mmol/L Ala).Ala supplementation reduced photosynthetic activity while boosting respiratory activity and pyruvate levels,indicating that *** used exogenous Ala for biomass accumulation through the respiratory metabolic *** accelerated respiratory metabolism due to Ala supplementation elevated the substrate pool and improved the lipogenic gene expression,promoting lipid production at *** study provided a novel method for increasing biomass accumulation and lipid production and elucidated the role of Ala in regulating lipid production.

关键词： alanine Chlorella pyrenoidosa lipid respiration lipogenic gene

Effect of periodic wide atmospheric pressure change on CO emission in closed goaf

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International Journal of Coal Science & Technology 2023年第4期10卷 139-150页

作者： Zhuangzhuang Shao Bo Tan Ruili Hu Xiaozhen Song Yan Guo tianze li Shuhui Fu Chaohuan Chen Haiyan Wang School of Emergency Management and Safety Engineering China University of Mining and Technology(Beijing)Beijing 100083China Security Department University of International Business and EconomicsBeijing 100029China School of Civil and Resources Engineering University of Science and Technology BeijingBeijing 100083China

Atmospheric pressure fuctuation is one of the most important factors afecting the climate environment and gas emission in the fre *** obtain the infuence rule of the surface atmospheric pressure change on the gas sampling and abnormal emission in the mine closed goaf,the No.1 coal mine in Dananhu was taken as the research *** Fourier transform and Fisher harmonic analysis and other statistical methods,the infuence of the periodic variation of atmospheric pressure on the gas leakage and outfow in the closed goaf was *** results showed that there were three atmospheric pressure periods of 15.2 d,1 d and 182.2 d,and the probability was greater than 95%.The time period with the highest number of atmospheric pressure peaks was 7:00–8:00,which accounted for 20.2%of total occurrence number in a *** the time periods with the highest number of atmospheric pressure trough were 2:00,15:00 and 16:00,accounting for 27.4%.The peak-to-trough transition time was mainly concentrated around 6 h,and the diurnal variation curve of atmospheric pressure was mainly *** atmospheric pressure change rate was mostly concentrated in 10–50 Pa/*** was determined that the distance that the gas sampling pipe was pre-laid into the inner side of the closed wall should be greater than 44.4 m,and the CO concentration and atmospheric pressure in the closed goaf were both periodic and negative with atmospheric *** research results have important guiding signifcance for the monitoring,early warning and environmental protection of the goaf.

关键词： Atmospheric pressure Periodic variation Closed goaf CO emission Coal mine

RESEARCH ON THE MOIRE CHROMATOGRAPHY TECHNIQUE AND ITS APPliCATION

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Journal of Innovative Optical Health Sciences 2009年第2期2卷 137-142页

作者： tianze li SHUYUN WANG School of Electrical and Electronic Engineering Shandong University of Technology Zibo 255049 China

This paper explains the Moire chromatography technique and the optical characteristics when the light crosses the 3D air flow *** on this,taking grating,CCD camera,optical filter and diaphragm as the main device,a multi-direction Moire chromatography optical system was *** system consists of five detective light paths,in each detective light path there is parallel and same periodic grating and filtering minipore placed on the lens’focal length plane;the grating is used to adjust the space length and angle between the two gratings,and the filtering minipore is used to remove the unorderly high frequency intermix in the Moire *** the computer escalator method to convert the tested value,the vivid interference fringe of tested parameter can be *** application of this system in precision measurement and medicine is also analyzed and discussed.

关键词： Moire chromatography optical system computer escalator method medicine

Diverse structures and antihepatoma effect of sesquiterpenoid dimers from Artemisia eriopoda by AKT/STAT signaling pathway

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Signal Transduction and Targeted Therapy 2023年第3期8卷 898-900页

作者： Xiaofeng He Wenjing Ma Jing Hu tianze li Changan Geng Yunbao Ma Mengfei Wang Kexin Yang Xuemei Zhang Ji-Jun Chen State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyChinese Academy of SciencesKunming 650201PR China University of Chinese Academy of Sciences Beijing 100049PR China

Dear Editor,liver cancer as a common malignant tumor has become a major source of morbidity and mortality worldwide.1 Currently,four synthetic drugs and three monoclonal antibody drugs have been approved for the treatment of hepatocellular carcinoma(HCC)since ***,the disadvantages of the above drugs such as low response rates,severe side effects,and drug resistance hamper their therapeutic *** and biologically diverse natural products are a major source in the search for novel antihepatoma agents.

关键词： drugs mortality liver

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边端协同环境中的任务卸载和资源分配方法

南京师大学报（自然科学版） 2024年第1期47卷 121-132页

作者：张俊娜赵豪李天泽赵晓焱王亚丽河南师范大学计算机与信息工程学院河南新乡453007

将终端任务卸载至边缘计算环境弥补了云计算距离较远而产生较大延迟的缺陷,同时还降低了设备能耗.但从资源方面来讲,边缘服务器的各类资源并不像云服务器那么充足,因此,任务卸载和资源分配的联合优化成为边缘计算的研究热点之一.已有的... 详细信息

将终端任务卸载至边缘计算环境弥补了云计算距离较远而产生较大延迟的缺陷,同时还降低了设备能耗.但从资源方面来讲,边缘服务器的各类资源并不像云服务器那么充足,因此,任务卸载和资源分配的联合优化成为边缘计算的研究热点之一.已有的任务卸载和资源分配联合优化研究通常假设任务卸载至单个边缘服务器,默认每个终端设备产生一个任务,即使有研究多服务器的,也通常忽略服务器间的负载均衡.为此,本文在一个多边缘服务器多用户多任务的边端系统中,提出了一种权衡时延、能耗和负载均衡指标(即效益)的任务卸载和资源分配方法,其通过优化任务卸载决策、服务器计算资源分配和终端设备发射功率,实现任务卸载效益最大化.最后,为了验证所提方法的有效性,进行了充分的对比实验.实验结果表明,与对比方法相比,所提出的方法在提升卸载效益和实现服务器间负载均衡方面有良好的性能.

关键词：边缘计算任务卸载资源分配负载均衡强化学习

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Dynamics and genetic regulation of macronutrient concentrations during grain development in maize

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Journal of Integrative Agriculture 2024年第3期23卷 781-794页

作者： Pengcheng li Shuangyi Yin Yunyun Wang tianze Zhu Xinjie Zhu Minggang Ji Wenye Rui Houmiao Wang Chenwu Xu Zefeng Yang Jiangsu Key Laboratory of Crop Genetics and Physiology/Key Laboratory of Plant Functional Genomics Ministry of Education/Jiangsu Key Laboratory of Crop Genomics and Molecular Breeding/Agricultural CollegeYangzhou UniversityYangzhou 225009China Jiangsu Co-lnnovation Center for Modern Production Technology of Grain Crops Yangzhou UniversityYangzhou 225009China

Nitrogen(N), phosphorus(P), and potassium(K) are essential macronutrients that are crucial not only for maize growth and development, but also for crop yield and quality. The genetic basis of macronutrient dynamics and accumulation during grain filling in maize remains largely unknown. In this study, we evaluated grain N, P, and K concentrations in 206 recombinant inbred lines generated from a cross of DH1M and T877 at six time points after pollination. We then calculated conditional phenotypic values at different time intervals to explore the dynamic characteristics of the N, P, and K concentrations. Abundant phenotypic variations were observed in the concentrations and net changes of these nutrients. Unconditional quantitative trait locus(QTL) mapping revealed 41 non-redundant QTLs, including 17, 16, and 14 for the N, P, and K concentrations, respectively. Conditional QTL mapping uncovered 39 non-redundant QTLs related to net changes in the N, P, and K concentrations. By combining QTL, gene expression, co-expression analysis, and comparative genomic data, we identified 44, 36, and 44 candidate genes for the N, P, and K concentrations, respectively, including GRMZM2G371058 encoding a Doftype zinc finger DNA-binding family protein, which was associated with the N concentration, and GRMZM2G113967encoding a CBL-interacting protein kinase, which was related to the K concentration. The results deepen our understanding of the genetic factors controlling N, P, and K accumulation during maize grain development and provide valuable genes for the genetic improvement of nutrient concentrations in maize.

关键词： maize nutrient concentration unconditional QTL mapping conditional QTL mapping dynamic trait