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Non-intrusive Load Monitoring Based on Graph Total Variation for Residential Appliances

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Journal of Modern Power Systems and Clean Energy 2024年第3期12卷 947-957页

作者： Xiaoyang Ma Diwen Zheng Xiaoyong Deng Ying Wang dawei Deng wei Li the College of Electrical Engineering Sichuan University State Grid Chongqing Electric Power Company State Grid Sichuan Electric Power Company State Grid Hubei Electric Power Company Limited Research Institute

Non-intrusive load monitoring is a technique for monitoring the operating conditions of electrical appliances by collecting the aggregated electrical information at the household power inlet. Despite several studies on the mining of unique load characteristics, few studies have extensively considered the high computational burden and sample training. Based on lowfrequency sampling data, a non-intrusive load monitoring algorithm utilizing the graph total variation(GTV) is proposed in this study. The algorithm can effectively depict the load state without the need for prior training. First, the combined Kmeans clustering algorithm and graph signals are used to build concise and accurate graph structures as load models. The GTV representing the internal structure of the graph signal is introduced as the optimization model and solved using the augmented Lagrangian iterative algorithm. The introduction of the difference operator reduces the computing cost and addresses the inaccurate reconstruction of the graph signal. With low-frequency sampling data, the algorithm only requires a little prior data and no training, thereby reducing the computing cost. Experiments conducted using the reference energy disaggregation dataset and almanac of minutely power dataset demonstrated the stable superiority of the algorithm and its low computational burden.

关键词： Load monitoring Costs Home appliances Hidden Markov models Training Kernel Clustering algorithms

Laser Wire Additive Manufacturing of Ti-6Al-4V Alloy and Its Machine Learning Study for Parameters Optimization(Invited)

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中国激光 2024年第4期51卷 182-198页

作者： Wu Junyi Zhang Bo Wang weihua Li weipeng Yao Xiyu Wang dawei Xing wei Yan Ming Department of Materials Science and Engineering Southern University of Science and TechnologyShenzhen 518055GuangdongChina Songshan Lake Materials Laboratory Dongguan 523830GuangdongChina Institute of Physics Chinese Academy of SciencesBeijing 100190China Jiaxing Research Institute Southern University of Science and TechnologyShenzhen 518055GuangdongChina High Performance Computing Department National Supercomputing CenterShenzhen 518055GuangdongChina

Ti-6Al-4V is a benchmark Ti alloy. Laser wire additive manufacturing(LWAM) offers advanced manufacturing capability to the alloy for applications possibly including exploration of outer space. As a typical multiple-variable process, LWAM is complex, which, however, can be analyzed, predicated or even optimized by artificial intelligence(AI) methods such as machine learning(ML). In this study, printing parameters of the Ti-6Al-4V is firstly optimized using single-track-single-layer experiments, and then single-track-multiple-layer samples are printed, whose properties in terms of hardness and compressive strength are analyzed subsequently by both experiments and ML. The two ML approaches, artificial neural network(ANN) and support vector machine(SVM), are employed to predict the experimental results, whose coefficients of determination R2 show good values. Further optimized properties are realized by adopting genetic algorithm(GA) and simulated annealing(SA) approaches, which contribute to high mechanical properties achieved, for instance, an engineering compressive strength of about 1694 MPa. The results here indicate that important mechanical properties of the LWAM-prepared Ti alloys can be well predicted and enhanced using suitable ML approaches.

关键词： artificial printing additive

double-cone ignition;streaked optical pyrometer;velocity interferometer system for any reflector

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High Power Laser Science and Engineering 2024年第1期12卷 52-59页

作者： dawei Yuan Shaojun Wang Huigang wei Haochen Gu Yu Dai Jiayong Zhong Yutong Li Gang Zhao Jie Zhang Key Laboratory of Optical Astronomy National Astronomical ObservatoriesChinese Academy of SciencesBeijingChina Institute of Frontiers in Astronomy and Astrophysics of Beijing Normal University BeijingChina Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijingChina Key Laboratory for Laser Plasmas(MOE)and School of Physics and Astronomy Shanghai Jiao Tong UniversityShanghaiChina Department of Astronomy Beijing Normal UniversityBeijingChina Collaborative Innovation Center of IFSA Shanghai Jiao Tong UniversityShanghaiChina School of Physical Sciences University of Chinese Academy of SciencesBeijingChina Songshan Lake Materials Laboratory DongguanChina

The velocity interferometer system for any reflector(VISAR) coupled with a streaked optical pyrometer(SOP) system is used as a diagnostic tool in inertial confinement fusion(ICF) experiments involving equations of state and shock timing.To validate the process of adiabatically compressing the fuel shell through precise tuning of shocks in experimental campaigns for the double-cone ignition(DCI) scheme of ICF, a compact line-imaging VISAR with an SOP system is designed and implemented at the Shenguang-II upgrade laser facility. The temporal and spatial resolutions of the system are better than 30 ps and 7 μm, respectively. An illumination lens is used to adjust the lighting spot size matching with the target size. A polarization beam splitter and λ/4 waveplate are used to increase the transmission efficiency of our system. The VISAR and SOP work at 660 and 450 nm, respectively, to differentiate the signals from the scattered lights of the drive lasers. The VISAR can measure the shock velocity. At the same time, the SOP system can give the shock timing and relative strength. This system has been used in different DCI campaigns, where the generation and propagation processes of multi-shock are carefully diagnosed.

关键词： double-cone ignition streaked optical pyrometer velocity interferometer system for any reflector

Ca and Sr co-doping induced oxygen vacancies in 3DOM La_(2-x)Sr_(x)Ce_(2-y)CayO_(7-δ)catalysts for boosting low-temperature oxidative coupling of methane

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Journal of Energy Chemistry 2024年第4期91卷 331-344页

作者： Tongtong Wu Yuechang wei Jing Xiong Yitao Yang Zhenpeng Wang dawei Han Zhen Zhao Jian Liu State Key Laboratory of Heavy Oil Processing China University of PetroleumBeijing 102249China Key Laboratory of Optical Detection Technology for Oil and Gas China University of PetroleumBeijing 102249China

It is urgent to develop catalysts with application potential for oxidative coupling of methane(OCM)at relatively lower temperature.Herein,three-dimensional ordered macro porous(3 DOM)La_(2-x)Sr_(x)Ce_(2-y)CayO_(7-δ)(A_(2)B_(2)O_(7)-type)catalysts with disordered defective cubic fluorite phased structure were successfully prepared by a colloidal crystal template method.3DOM structure promotes the accessibility of the gaseous reactants(O2and CH4)to the active sites.The co-doping of Ca and Sr ions in La_(2-x)Sr_(x)Ce_(2-y)CayO_(7-δ)catalysts improved the formation of oxygen vacancies,thereby leading to increased density of surface-active oxygen species(O_(2)^(-))for the activation of CH4and the formation of C2products(C2H6and C2H4).3DOM La_(2-x)Sr_(x)Ce_(2-y)CayO_(7-δ)catalysts exhibit high catalytic activity for OCM at low temperature.3DOM La1.7Sr0.3Ce1.7Ca0.3O7-δcatalyst with the highest density of O_(2)^(-)species exhibited the highest catalytic activity for low-temperature OCM,i.e.,its CH4conversion,selectivity and yield of C2products at 650℃are 32.2%,66.1%and 21.3%,respectively.The mechanism was proposed that the increase in surface oxygen vacancies induced by the co-doping of Ca and Sr ions boosts the key step of C-H bond breaking and C-C bond coupling in catalyzing low-temperature OCM.It is meaningful for the development of the low-temperature and high-efficient catalysts for OCM reaction in practical application.

关键词： 3DOM catalysts Ca ions Sr ions Low-temperature oxidative couplingof methane Oxygen vacancies O_(2)^(-) species

Direct observation of oxygen vacancy formation and migration over ceria surface by in situ environmental transmission electron microscopy

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Journal of Rare Earths 2024年第4期42卷 676-682页

作者： dawei Pang wei Li Ningqiang Zhang Hong He Shengcheng Mao Yanhui Chen Liwei Cao Chong Li Ang Li Xiaodong Han Beijing Key Laboratory of Solid Microstructure and Properties Department of Materials and ManufacturingBeijing University of TechnologyBeijing 100124China Beijing Key Laboratory for Green Catalysis and Separation The Faculty of Environment and LifeBeijing University of TechnologyBeijing10124China International Joint Research Laboratory for Quantum Functional Materials of Henan School of Physics and MicroelectronicsZhengzhou UniversityZhengzhou450001China

The extremely high structural tolerance of ceria to oxygen vacancies(Ov)has made it a desirable catalytic material for the hydrocarbon oxidation to chemicals and pharmaceuticals and the reduction of gaseous pollutants.It is proposed that the formation and diffusion of Ov originate from its outstanding reduction property.However,the formation and diffusion process of Ov over the surface of ceria at the atomic level is still unknown.Herein,the structural and valence evolution of CeO_(2)(111)surfaces in reductive,oxidative and vacuum environments from room temperature up to 700℃was studied with in situ aberration-corrected environmental transmission electron microscopy(ETEM)experiments.Ov is found to form under a high vacuum at elevated temperatures;however,the surface can recover to the initial state through the adsorption of oxygen atoms in an oxygen-contained environment.Furthermore,in hydrogen environment,the step-CeO_(2)(111)surface is not stable at elevated temperatures;thus,the steps tend to be eliminated with increasing temperature.Combined with first-principles density function calculations(DFT),it is proposed that O-terminated surfaces would develop in a hypoxic environment due to the dynamic diffusion of Ov from the outer surface to the subsurface.Furthermore,in a reductive environment,H2 facilitates the formation and diffusion of Ov while Ce-terminated surfaces develope.These results reveal dynamic atomic-scale interplay between the nanoceria surface and gas,thereby providing fundamental insights into the Ov-dependent reaction of nano-CeO_(2) during catalytic processes.

关键词： Ceria Direct observation In situ ETEM Oxygen vacancy Density function calculations Rareearths

Metal size effects over metal/zeolite bifunctional catalysts in the selective hydroalkylation of benzene

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Frontiers of Chemical Science and Engineering 2024年第4期18卷 107-114页

作者： Junjie Li Chuang Liu Zhenlong Jia Yingchun Ye dawei Lan wei Meng Jianqiang Wang Zhendong Wang Yongfeng Hu weimin Yang State Key Laboratory of Green Chemical Engineering and Industrial Catalysis Sinopec Shanghai Research Institute of Petrochemical Technology Co.Ltd.Shanghai 201208China School of Chemical Engineering East China University of Science and TechnologyShanghai 200237China

Bifunctional metal/zeolite materials are some of the most suitable catalysts for the direct hydroalkylation of benzene to cyclohexylbenzene.The overall catalytic performance of this reaction is strongly influenced by the hydrogenation,which is dependent on the metal sizes.Thus,systematically investigating the metal size effects in the hydroalkylation of benzene is essential.In this work,we successfully synthesized Ru and Pd nanoparticles on Sinopec Composition Materials No.1 zeolite with various metal sizes.We demonstrated the size-dependent catalytic activity of zeolite-supported Ru and Pd catalysts in the hydroalkylation of benzene,which can be attributed to the size-induced hydrogen spillover capability differences.Our work presents new insights into the hydroalkylation reaction and may open up a new avenue for the smart design of advanced metal/zeolite bi-functional catalysts.

关键词： size effects bifunctional catalysts metal/zeolite hydroalkylation

Functional nanoemulsions: Controllable low-energy nanoemulsification and advanced biomedical application

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Chinese Chemical Letters 2024年第2期35卷 57-69页

作者： Maojie Zhang Qiang Cao Yuming Yuan Xiaohan Guo dawei Pan Rui Xie Xiaojie Ju Zhuang Liu wei Wang Liangyin Chu College of Engineering Sichuan Normal UniversityChengdu 610101China School of Chemical Engineering Sichuan UniversityChengdu 610065China State Key Laboratory of Polymer Materials Engineering Sichuan UniversityChengdu 610065China

Nanoemulsions are widely used as advanced pharmaceutical delivery systems in biomedical field, due to their high encapsulation efficiency and good therapy efficacy.Nanoemulsification techniques that produce nanoemulsions with controllable sizes and compositions are promising for creating advanced nanoemulsion systems for pharmaceutical delivery.This review summarizes recent advances on low-energy emulsification techniques for producing nanoemulsions, and the use of these nanoemulsions as advanced pharmaceutical delivery systems and as templates to create drug-loaded functional particles for biomedical application.First, nanoemulsification techniques that utilize elaborate interfacial physics/chemistry and micro-/nano-fluidics, featured with relatively-low energy input, to produce nanoemulsions with controllable sizes and compositions, are introduced.Uses of these nanoemulsions to create nanoemulsionincorporated milli-particles, drug-loaded nanoparticles and nanoparticle-incorporated microparticles with sizes ranging from several millimeters to sub-10 nm are emphasized.Flexible and efficient use of the nanoemulsions, functional nanoparticles and milli-/micro-particles integrated with nanoemulsions or nanoparticles for advanced pharmaceutical delivery in biomedical field are highlighted, with focus on how the interplay between their sizes and compositions achieve desired pharmaceutical-delivery performances.Finally, perspectives on further advances on the controllable production of nanoemulsions are provided.

关键词： Nanoemulsions Interfaces Drug delivery Template synthesis Nanoparticles

Targeted mutations of BnPAP2 lead to a yellow seed coat in Brassica napus L.

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Journal of Integrative Agriculture 2024年第2期23卷 724-730页

作者： wei Huang Ruyu Jiao Hongtao Cheng Shengli Cai Jia Liu Qiong Hu Lili Liu Bao Li Tonghua Wang Mei Li dawei Zhang Mingli Yan Hunan Research Center of Heterosis Utilization in Rapeseed/Crop Research Institute Hunan Academy of Agricultural SciencesChangsha 410125China Hunan Key Laboratory of Economic Crops Genetic Improvement and Integrated Utilization/School of Life and Health Science Hunan University of Science and TechnologyXiangtan 411201China Key Laboratory of Biology and Genetic Improvement of Oil Crops Ministry of Agriculture and Rural Affairs/Oil Crops Research InstituteChinese Academy of Agricultural SciencesWuhan 430062China

The yellow seed trait is preferred by breeders for its potential to improve the seed quality and commercial value of Brassica napus.In the present study,we produced yellow seed mutants using a CRISPR/Cas9 system when the two BnPAP2 homologs were knocked out.Histochemical staining of the seed coat demonstrated that proanthocyanidin accumulation was significantly reduced in the pap2 double mutants and decreased specifically in the endothelial and palisade layer cells of the seed coat.Transcriptomic and metabolite profiling analysis suggested that disruption of the BnPAP2 genes could reduce the expression of structural and regulated genes in the phenylpropanoid and flavonoid biosynthetic pathways.The broad suppression of these genes might hinder proanthocyanidin accumulation during seed development,and thereby causing the yellow seed trait in B.napus.These results indicate that BnPAP2 might play a vital role in the regulatory network controlling proanthocyanidin accumulation.

关键词： yellow seed BnPAP2 proanthocyanidins CRISPR/Cas9

Improve meat production and virus resistance by simultaneously editing multiple genes in livestock using Cas12i^(Max)

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Science China(Life Sciences) 2024年第3期67卷 555-564页

作者： Jilong Ren Tang Hai Yangcan Chen Ke Sun Zhiqiang Han Jing Wang Chongyang Li Qingwei Wang Leyun Wang Huabing Zhu dawei Yu wei Li Shanjiang Zhao State Key Laboratory of Animal Nutrition Key Laboratory of Animal GeneticsBreeding and Reproduction of Ministry of Agriculture and Rural AffairsInstitute of Animal ScienceChinese Academy of Agricultural SciencesBeijing 100193China State Key Laboratoryf Stem Cell and Reproductive Biology Instituteof ZooogyChinese Academyof SciencesBeijing 100101China Beijing Institute for Stem Cell and Regenerative Medicine Beijing 100101China Beijing Farm Animal Research Center Institute of ZoologyChinese Academy of SciencesBeijing 100101China

The clustered regularly interspaced short palindromic repeats(CRISPR)/CRISPR-associated gene(Cas) system is continually optimized to achieve the most efficient gene editing effect. The Cas12i^(Max), a Cas12i variant, exhibits powerful DNA editing activity and enriches the gene editing toolbox. However, the application of Cas12i^(Max)in large domestic animals has not yet been reported. To verify the efficiency and feasibility of multiple gene editing in large animals, we generated porcine fibroblasts with simultaneous knockouts of IGF2, ANPEP, CD163,and MSTN via Cas12i^(Max)in one step. Phenotypically stable pigs were created through somatic cell nuclear transfer technology. They exhibited improved growth performance and muscle quality. Furthermore, we simultaneously edited three genes in bovine fibroblasts. A knockout of MSTN and PRNP was created and the amino acid Q-G in CD18 was precisely substituted. Meanwhile, no off-target phenomenon was observed by sum-type analysis or off-target detection. These results verified the effectiveness of Cas12i^(Max)for gene editing in livestock animals and demonstrated the potential application of Cas12i^(Max)in the field of animal trait improvement for agricultural production.

关键词： Cas12i^(Max) gene editing livestock multiple trait improvement