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Fine-grained grid computing model for Wi-Fi indoor localization in complex environments

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Journal of Electronic Science and Technology 2024年第1期22卷 42-52页

作者： Yan Liang song chen Xin Dong Tu Liu School of Computer Engineering Chengdu Technological UniversityChengdu611730China HAN Networks Corporation Limited Beijing100094China

The fingerprinting-based approach using the wireless local area network(WLAN)is widely used for indoor ***,the construction of the fingerprint database is quite *** when the position of the access point(AP)or wall changes,updating the fingerprint database in real-time is *** appropriate indoor localization approach,which has a low implementation cost,excellent real-time performance,and high localization accuracy and fully considers complex indoor environment factors,is preferred in location-based services(LBSs)*** this paper,we proposed a fine-grained grid computing(FGGC)model to achieve decimeter-level localization *** points(RPs)are generated in the grid by the FGGC ***,the received signal strength(RSS)values at each RP are calculated with the attenuation factors,such as the frequency band,three-dimensional propagation distance,and walls in complex *** a result,the fingerprint database can be established automatically without manual measurement,and the efficiency and cost that the FGGC model takes for the fingerprint database are superior to previous *** proposed indoor localization approach,which estimates the position step by step from the approximate grid location to the fine-grained location,can achieve higher real-time performance and localization accuracy *** mean error of the proposed model is 0.36 m,far lower than that of previous ***,the proposed model is feasible to improve the efficiency and accuracy of Wi-Fi indoor *** also shows high-accuracy performance with a fast running speed even under a large-size *** results indicate that the proposed method can also be suitable for precise marketing,indoor navigation,and emergency rescue.

关键词： Fine-grained grid computing (FGGC) Indoor localization Path loss Random forest Reference points(RPs)

A novel algorithm for evaluating cement azimuthal density based on perturbation theory in horizontal well

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Petroleum Science 2024年第1期21卷 244-251页

作者： Ji-Lin Fan Feng Zhang Qian chen Hao-chen song Lu-Yu Zhong Yue-Xiang Dai National Key Laboratory of Deep Oil and Gas School of GeosciencesChina University of Petroleum(East China)Qingdao 266580ShandongChina China National Logging Corporation Xi'an 710076ShaanxiChina Sinopec Matrix Corporation Qingdao 266001ShandongChina

Cement density monitoring plays a vital role in evaluating the quality of cementing projects,which is of great significance to the development of oil and ***,the presence of inhomogeneous cement distribution and casing eccentricity in horizontal wells often complicates the accurate evaluation of cement azimuthal *** this regard,this paper proposes an algorithm to calculate the cement azimuthal density in horizontal wells using a multi-detector gamma-ray detection *** spatial dynamic response functions are simulated to obtain the influence of cement density on gamma-ray counts by the perturbation theory,and the contribution of cement density in six sectors to the gamma-ray recorded by different detectors is obtained by integrating the spatial dynamic response *** with the relationship between gamma-ray counts and cement density,a multi-parameter calculation equation system is established,and the regularized Newton iteration method is employed to invert casing eccentricity and cement azimuthal *** approach ensures the stability of the inversion process while simultaneously achieving an accuracy of 0.05 g/cm^(3) for the cement azimuthal *** accuracy level is ten times higher compared to density accuracy calculated using calibration ***,this algorithm enhances the accuracy of cement azimuthal density evaluation,provides valuable technical support for the monitoring of cement azimuthal density in the oil and gas industry.

关键词： Cement azimuthal density Perturbation theory Casing eccentricity Spatial dynamic response function Regularized Newton iteration

Synthesis and potential osteogenic applications of Wnt3a-loaded ZIF-8 nanoparticles

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Chinese Chemical Letters 2024年第3期35卷 399-405页

作者： Hengfei Wang song chen Zihan He Junyu chen Zhou Zhu Qianbing Wan Jian Wang Xibo Pei State Key Laboratory of Oral Diseases National Clinical Research Center for Oral DiseasesDepartment of ProsthodonticsWest China Hospital of StomatologySichuan UniversityChengdu 610041China Chongqing Key Laboratory of Oral Diseases and Biomedical Sciences Chongqing Municipal Key Laboratory of Oral Biomedical Engineering of Higher EducationStomatological Hospital of Chongqing Medical UniversityChongqing 400016China

The Wnt signaling pathway plays a critical role in bone homeostasis,and the related protein therapy strategies have been reported to have great potential in osseointegration;however,they face formidable challenges such as complex external environments and unavoidable protein *** this work,we report a novel approach combining the synthesis of metal–organic frameworks(MOFs)and protein encapsulation in a one-pot process based on zeolitic imidazolate framework-8(ZIF-8)and Wnt3a protein,with improved biomechanical behavior and enhanced protein biological *** combination was designed to enhance the Wnt3a protein function through the improved chemical stability provided by the ZIF-8 ***,the zinc ions contained in the ZIF-8 crystals induced bone homeostasis,further favoring the *** results showed that the Wnt3a protein-loaded ZIF-8 crystals served as efficient drug delivery vehicles to promote osteogenesis,preventing protein *** particular,Wnt3a-loaded ZIF-8 nanoparticles(Wnt3a@ZIF-8 NPs)had higher efficacy on bone marrow mesenchymal stem cells(BMSCs)than ZIF-8 NPs or Wnt3a proteins,contributing to the osteogenesis through ZIF-8 crystals and intracellular Wnt3a proteins released from Wnt3a@ZIF-8 ***,polymerase chain reaction(PCR)analysis showed that the osteogenic pathways were ***,the present one-pot process can open up new avenues to develop signaling protein-delivery systems for applications in protein therapy strategies.

关键词： Metal–organic frameworks Nanoparticle Drug release Osteogenesis Bone defects

A defective iron-based perovskite cathode for high-performance IT-SOFCs:Tailoring the oxygen vacancies using Nb/Ta co-doping

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Journal of Energy Chemistry 2024年第1期88卷 306-316,I0008页

作者： Bayu Admasu Beshiwork Xinyu Wan Min Xu Haoran Guo Birkneh Sirak Teketel Yu chen Jun song chen Tingshuai Li Enrico Traversa School of Materials and Energy University of Electronic Science and Technology of ChinaChengdu 611731SichuanChina The Future Laboratory Tsinghua UniversityBeijing 100084China School of Chemical Sciences University of Chinese Academy of SciencesBeijing 100049China Schoolof Environment and Energy South China University of Technlogy Guangzhou 50006GuangongChina Institute for Advanced Study Chengdu UniversityChengdu 610106SichuanChina

The sluggish kinetics of the electrochemical oxygen reduction reaction(ORR)in intermediatetemperature solid oxide fuel cells(IT-SOFCs)greatly limits the overall cell *** this study,an efficient and durable cathode material for IT-SOFCs is designed based on density functional theory(DFT)calculations by co-doping with Nb and Ta the B-site of the SrFeO_(3-δ)perovskite *** DFT calculations suggest that Nb/Ta co-doping can regulate the energy band of the parent SrFeO_(3-δ)and help electron *** symmetrical cells,such cathode with a SrFe_(0.8)Nb_(0.1)Ta_(0.1)O_(3-δ)(SFNT)detailed formula achieves a low cathode polarization resistance of 0.147Ωcm^(2) at 650℃.Electron spin resonance(ESR)and X-ray photoelectron spectroscopy(XPS)analysis confirm that the co-doping of Nb/Ta in SrFeO_(3-δ)B-site increases the balanced concentration of oxygen vacancies,enhancing the electrochemical performance when compared to 20 mol%Nb single-doped perovskite *** cathode button cell with NiSDC|SDC|SFNT configuration achieves an outstanding peak power density of 1.3 W cm^(-2)at 650℃.Moreover,the button cell shows durability for 110 h under 0.65 V at 600℃ using wet H_(2) as fuel.

关键词： Solid oxide fuel cell Cathode Oxygen reduction reaction Power density DFT calculation

Optimizing FeCoNiCrTi high-entropy alloy with hydrogen pumping effect to boost de/hydrogenation performance of magnesium hydride

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Rare Metals 2024年第7期43卷 3273-3285页

作者： Meng-chen song Fu-Ying Wu Yi-Qun Jiang Xiu-Zhen Wang Hu Zhao Li-Xin chen Liu-Ting Zhang School of Energy and Power Instrumental Analysis CenterJiangsu University of Science and Technology Max Planck Institute for Iron Research School of Mechanical and Aerospace Engineering Nanyang Technological University State Key Laboratory of Silicon Materials Department of Materials Science and EngineeringZhejiang University

The exploration of efficient,long-lived and cost-effective transition metal catalysts is highly desirable for the practical hydrogen storage of magnesium hydride（MgH2） in sustainable energy ***,FeCoNiCrTi high-entropy alloy（HEA） nanosheets were prepared via a facile wet chemical ball milling strategy and they were introduced into MgH2to boost the hydrogen storage *** refined HEA exhibited superior catalytic activity on *** contrast to additive-free MgH2,the initial desorption temperature of the constructed MgH2-HEA composite was reduced from 330.0 to 198.5℃ and a remarkable 51% reduction in the dehydrogenation activation energy was ***,the MgH2-HEA composite only required one-twentieth time of that consumed by pure MgH2to absorb 5.0 wt% of H2at 225℃.The synergy between the "hydrogen pumping" effect of Mg2Ni/Mg2NiH4and Mg2Co/Mg2CoH5couples,as well as the good dispersion of Fe,Cr and Ti on the surface of MgH2contributed to the enhanced de/hydrogenation performance of the MgH2-HEA *** study furnishes important steering for the design and fabrication of multiple transition metal catalysts and may push the commercial application of magnesium-based hydrides one step forward.

关键词： Hydrogen storage Magnesium hydride High-entropy alloys Catalysis

Monothetic and conductive network and mechanical stress releasing layer on micron-silicon anode enabling high-energy solid-state battery

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Rare Metals 2024年第3期43卷 1017-1029页

作者： Xiang Han Min Xu Lan-Hui Gu Chao-Fei Lan Min-Feng chen Jun-Jie Lu Bi-Fu Sheng Peng Wang song-Yan chen Ji-Zhang chen College of Materials Science and Engineering Co-Innovation Center of Efficient Processing and Utilization of Forestry ResourcesNanjing Forestry UniversityNanjing210037China Department of Physics Xiamen UniversityXiamen361005China Western Digital Corporation MilpitasCA95035USA

Silicon has ultrahigh capacity,dendrite-free alloy lithiation mechanism and low cost and has been regarded as a promising anode candidate for solid-state *** to the low infiltration of solid-state electrolyte(SSE),not the unstable solid-electrolyte interphase(SEI),but the huge stress during lithiation-and delithiation-induced particle fracture and conductivity lost tend to be the main *** this study,starting with micron-Si,a novel monothetic carbon conductive framework and a MgO coating layer are designed,which serve as electron pathway across the whole electrode and stress releasing layer,*** addition,the in situ reaction between Si and SSE helps to form a LiF-rich and mechanically stable SEI *** a result,the mechanical stability and charge transfer kinetics of the uniquely designed Si anode are significantly ***,high initial Coulombic efficiency,high capacity and durable cycling stability can be achieved by applying the Si@MgO@C anode in *** example,high specific capacity of 3224.6 mAh·g^(-1)and long cycling durability of 200 cycles are *** work provides a new concept for designing alloy-type anode that combines surface coating on particle and electrode structure design.

关键词： Lithium-ion battery(LIB) Solid-state electrolyte(SSE) Silicon anode Stress relief Coating

Aquaporin-3 promotes proliferation and inflammation in hepatocellular carcinoma

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Genes & Diseases 2024年第4期11卷 45-48页

作者： Yao Wang Yalan Wu Xueying Li Weiwei song Fengling Zheng Xiaoying Mo Yi Luo Yun Li song chen Huanhuan Luo School of Basic Medical Sciences Guangzhou University of Chinese MedicineGuangzhouGuangdong 510006China The School of Health Guangzhou Vocational University of Science andTechnologyGuangzhouGuangdong 510555China Zhongshan Hospital of Traditional Chinese Medicine ZhongshanGuangdong 528401China The Journal Center Guangzhou University of Chinese MedicineGuangzhouGuangdong 510006China Jiangsu Vocational College of Medicine YanchengJiangsu 224005China Science and Technology Innovation Center Guangzhou University of Chinese MedicineGuangzhouGuangdong 510006China State Key Laboratory of Dampness Syndrome of Chinese Medicine GuangzhouGuangdong 510006China

Carcinogenesis is closely associated with *** have shown that lipopolysaccharides(LPS)can contribute to hepatocellular carcinoma(HC)development by inducing IL-6 and TNF-αproduction from the hepatic progenitor cells.1 Aquaporin 3(AQP3),a water channel protein,has recently been found to play a critical role in cancer-associated inflammation.

关键词： inflammation. hepatocellular inflammation

OCTA characteristics in non-arteritic central retinal artery occlusion and correlation with visual acuity

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International Journal of Ophthalmology(English edition) 2024年第2期17卷 289-296页

作者： Hong-Xia Gong Bin Wu Shi-Yong Xie Wei Zhang song chen Tianjin Key Lab of Ophthalmology and Visual Science Department of Ophthalmology for Integrated Traditional Chinese and Western MedicineTianjin Eye HospitalTianjin 300020China Clinical College of Ophthalmology Tianjin Medical UniversityTianjin 300010China Eye Hospital Affiliated to Nankai University Tianjin 300020China

AIM:To observe the retinal and choroidal circulations in patients with non-arteritic permanent central retinal artery occlusion(NA-CRAO)via optical coherence tomography angiography(OCTA)and analyze their correlation with visual ***:Sixty-two eyes with clinically confirmed acute NA-CRAO were included in the study and divided into:A type(mild n=29),B type(moderate n=27)and C type(severe n=6)based on the degree of visual loss,retinal edema,and arterial blood flow delay in fundus fluorescence angiography(FFA).Contralateral healthy eyes were used as the control ***-corrected visual acuity(BCVA),slit lamp microscopy,indirect ophthalmoscopy,fundus color photography,OCTA,and FFA were ***’s correlation analysis was used to determine the correlations between retinal and choroidal vessels and visual ***:There were no statistically significant differences in age,gender,and intraocular pressure among the three types and the control group(P>0.05).Vessel density in deep capillary plexus(VD-DCP)significantly decreased(P<0.05)in all three types of NA-CRAO patients compared to the control *** density in superficial vascular plexus(VD-SVP)significantly decreased(P<0.05)in type A patients and choriocapillaris flow area significantly decreased(P<0.05)in type B and type C patients compared to the control group;while outer retinal flow areas significantly increased in the type A(P<0.05)and decreased in type C patients(P<0.05).The retinal thickness significantly increased in type C group(P<0.05).The VD-SVP at fovea in the type A was significantly lower than both of type B and *** VD-SVP at nasal parafovea in type A and B was significantly lower than type C(P<0.05).The logMAR BCVA of type A was significantly better than that of type B and C groups(P<0.05).Spearman’s correlation analysis showed that the logMAR BCVA was positively correlated with VD-SVP at fovea(r=0.679,P=0.031)and nasal parafovea(r=0.826,P=0.013).CONCLUSION:OCTA is valua

关键词： non-arteritic central retinal artery occlusion fundus fluorescence angiography optical coherence tomography angiography retinal vessel density visual acuity

Segmented Linear Regression Trees

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Acta Mathematica Sinica,English Series 2024年

作者： Xiang Yu ZHENG song Xi chen JD Technology Peking University

Tree-based models have been widely applied in both academic and industrial settings due to the natural interpretability, good predictive accuracy, and high scalability. In this paper, we focuses on improving the single-tree method and propose the segmented linear regression trees(SLRT) model that replaces the traditional constant leaf model with linear ones. From the parametric view, SLRT can be employed as a recursive change point detect procedure for segmented linear regression(SLR)models, which is much more efficient and flexible than the traditional grid search method. Along this way, we propose to use the conditional Kendalls τ correlation coefficient to select the underlying change points. From the non-parametric view, we propose an efficient greedy splitting method that selects the splits by analyzing the association between residuals and each candidate split variable. Further, with the SLRT as a single-tree predictor, we propose a linear random forest approach that aggregates the SLRTs by a weighted average. Both simulation and empirical studies showed significant improvements than the CART trees and even the random forest.

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