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Research on Recommendation Algorithms Based on Cloud Models in Probabilistic Linguistic Environments

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Journal of Systems Science and Information 2024年第1期12卷 96-112页

作者： Peng YANG Xifeng MA meng WEI Chunsheng CUI Libin che College of Computer and Information Engineering Henan University of Economics and LawZhengzhou 450046China

To solve the problem that the traditional cloud model can't directly process the textual review information in the recommendation algorithm,this paper combines the merits of the cloud model in transforming qualitative and quantitative knowledge with the multi-granularity advantages of probabilistic linguistic term sets in representing uncertain information,and proposes a recommendation algorithm based on cloud model in probabilistic language environment.Initially,this paper quantifies the attributes in the review text based on the probabilistic linguistic term set.Subsequently,the maximum deviation method is used to determine the weight of each attribute in the evaluation information of the product to be recommended,and the comprehensive evaluation number and attribute weight are converted into the digital characteristic value of the cloud model by using the backward cloud generator.Finally,the products are recommended and sorted based on the digital characteristic value of the cloud model.The algorithm is applied to the recommendation of 10 hotels,and the results show that the method is effective and practical,enriching the application of cloud models in the recommendation field.

关键词： recommendation algorithm cloud model probabilistic linguistic term set text reviews

Cell replacement with stem cell-derived retinal ganglion cells from different protocols

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Neural Regeneration Research 2024年第4期19卷 807-810页

作者： Ziming Luo Kun-che Chang Spencer Center for Vision Research Byers Eye InstituteStanford University School of Medicine Department of Ophthalmology Louis J.Fox Center for Vision RestorationUniversity of Pittsburgh School of Medicine Department of Neurobiology Center of NeuroscienceUniversity of Pittsburgh School of Medicine

Glaucoma,characterized by a degenerative loss of retinal ganglion cells,is the second leading cause of blindness worldwide.There is currently no cure for vision loss in glaucoma because retinal ganglion cells do not regenerate and are not replaced after injury.Human stem cell-derived retinal ganglion cell transplant is a potential therapeutic strategy for retinal ganglion cell degenerative diseases.In this review,we first discuss a 2D protocol for retinal ganglion cell differentiation from human stem cell culture,including a rapid protocol that can generate retinal ganglion cells in less than two weeks and focus on their transplantation outcomes.Next,we discuss using 3D retinal organoids for retinal ganglion cell transplantation,comparing cell suspensions and clusters.This review provides insight into current knowledge on human stem cell-derived retinal ganglion cell differentiation and transplantation,with an impact on the field of regenerative medicine and especially retinal ganglion cell degenerative diseases such as glaucoma and other optic neuropathies.

关键词： cell clumps cell suspension cell transplantation differentiation direct-induced protocol glaucoma optic neuropathy regenerative medicine retinal ganglion cell retinal organoids stem cells

Evaluating the performance and influencing factors of three portable black carbon monitors for field measurement

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Journal of Environmental Sciences 2024年第5期139卷 320-333页

作者： Liqing Wu Yicheng Shen Fei che Yuzhe Zhang Jian Gao Chong Wang State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100012China Jinan Ecological Environmental Protection Grid-Based Supervision Center Jinan 250013China

Black carbon(BC)is associated with adverse human health and climate change.Mapping BC spatial distribution imperatively requires low-cost and portable devices.Several portable BC monitors are commercially available,but their accuracy and reliability are not always satisfactory during continuous field observation.This study evaluated three models of portable black carbon monitors,C12,MA350 and DST,and investigates the factors that affect their performance.The monitors were tested in urban Beijing,where portable devices running for one month alongside a regular-size reference aethalometer AE33.The study considers several factors that could influence the monitors'performance,including ambient weather,aerosol composition,loading artifacts,and built-in algorithms.The results show that MA350and DST present considerable discrepancies to the reference instrument,mainly occurring at lower concentrations(0-500 ng/m^(3))and higher concentrations(2500-8000 ng/m^(3)),respectively.These discrepancies were likely caused by the anomalous noise of MA350 and the loading artifacts of DST.The study also suggests that the ambient environment has limited influence on the monitors'performance,but loading artifacts and accompanying compensation algorithms can result in unrealistic data.Based on the evaluation,the study suggests that C12 is the best choice for unsupervised field measurement,DST should be used in scenarios where frequent maintenance is available,and MA350 is suitable for research purposes with post-processing applicable.The study highlights the importance of assigning portable BC monitors to appropriate applications and the need for optimized real-time compensation algorithms.

关键词： Black carbon Aethalometer Loading artifact Performance evaluation Portable device

Management of retroperitoneal high-grade serous carcinoma of unknown origin:A case report

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World Journal of Clinical Cases 2024年第6期12卷 1190-1195页

作者： Wen-Lin hsieh Dah-Ching Ding Department of Obstetrics and Gynecology Hualien Tzu Chi HospitalBuddhist Tzu Chi Medical FoundationTzu Chi UniversityHualien 970Taiwan Institute of Medical Sciences Tzu Chi UniversityHualien 970TaiwanTaiwan

BACKGROUND Retroperitoneal high-grade serous carcinoma(HGSC)of unknown origin is a sporadic tumor that can originate from ovarian cancer.Herein,we report the case of a woman with retroperitoneal HGSC of unknown origin and describe how she was diagnosed and treated.CASE SUMMARY A 71-year-old female presented with the tumor marker CA125 elevated to 1041.9 U/mL upon a regular health examination.Computed tomography revealed retroperitoneal lymph node enlargement.Subsequently,positron emission tomography scanning revealed lesions with increased F-18 fluorodeoxyglucose uptake at the nodes.As a result,she underwent laparoscopic lymph node resection,and pathology revealed metastatic adenocarcinoma with CK7(+),PAX8(+),WT1(+),PR(-),and p53 mutational loss of expression,indicating that the origin may be from the adnexa.The patient was admitted to our ward and underwent laparoscopic staging;however,the pathological results were negative.Under the suspicion of retroperitoneal HGSC of unknown origin,chemotherapy and targeted therapy were initiated.Tumor marker levels decreased after treatment.CONCLUSION We present a case of HGSC of unknown origin managed using retroperitoneal lymphadenectomy,staging surgery,chemotherapy,and targeted therapy.

关键词： High-grade serous carcinoma Retroperitoneum Origin chemotherapy Lymph node Case report

Origins of perturbations in dayside equatorial ground magnetograms

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Earth and Planetary Physics 2024年第1期8卷 215-221页

作者： Syau-Yun W.hsieh David G.Sibeck The Johns Hopkins University Applied Physics Laboratory LaurelMarylandUSA NASA Goddard Space Flight Center GreenbeltMarylandUSA

To determine the cause(s)of perturbations seen in dayside equatorial ground magnetograms,we conducted a systematic survey of simultaneous ground-based and geosynchronous satellite-based observations during the 90-day period from December 1,2020 to February 28,2021.We examined Huancayo ground magnetometer observations from 14:00:00 to 20:00:00 UT each day,during which Huancayo passed through local noon.From those data we chose perturbation events selected on the basis of large(>20 nT)event amplitude and classified the selected events as responding primarily to solar wind pressure,or to variations in the north/south component of the interplanetary magnetic field(IMF Bz),or perhaps in part to both.The results show that an equivalent number of events were identified for each model during this 90-day period.Variations in the lagged solar wind dynamic pressure routinely correspond to nearly simultaneous sudden impulses recorded at both geosynchronous orbit and on the ground.Variations in IMF Bz produce erosion signatures at geosynchronous orbit and can correspond to ground events if lag times for reconnection to enhance convection in the magnetosphere are taken into account.

关键词： dayside magnetosphere dayside equatorial ionosphere geosynchronous magnetic field

Decomposition mechanisms of nuclear-grade cationic exchange resin by advanced oxidation processes:Statistical molecular fragmentation model and DFT calculations

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Journal of Environmental Sciences 2024年第1期135卷 433-448页

作者： Xiang meng Pierre Désesquelles Lejin Xu Department of Nuclear Engineering and Technology School of Energy and Power EngineeringHuazhong University of Science&TechnologyWuhan 430074China CNRS Laboratoire de Physique des Gaz et des PlasmasUniversitéParis-SaclayOrsay 91405France State Key Laboratory of Coal Combustion School of Energy and Power EngineeringHuazhong University of Science and TechnologyWuhan 430074China

The treatment and disposal of radioactive waste are presently facing great challenges.Spent ion exchange resins have become a focus of attention due to their high production and serious environmental risks.In this paper,a simplified model of cationic exchange resin is proposed,and the degradation processes of cationic resin monomer initiated by hydroxyl radicals(·OH)are clarified by combining statistical molecular fragmentation(SMF)model and density functional theory(DFT)calculations.The prediction of active sites indicates that the S-O bonds and the C-S bond of the sulfonic group are more likely to react during the degradation.The meta-position of the sulfonic group on the benzene ring is the most active site,and the benzene ring without the sulfonic group has a certain reactivity.The C11-C14 and C17-C20 bonds,on the carbon skeleton,are the most easily broken.It is also found that dihydroxy addition and elimination reactions play a major role in the process of desulfonation,carbon skeleton cleavage and benzene ring separation.The decomposition mechanisms found through the combination of physical models and chemical calculations,provide theoretical guidance for the treatment of complex polycyclic aromatic hydrocarbons.

关键词： Cationic exchange resin Statistical molecular fragmentation model Density functional theory Hydroxyl radical Decomposition mechanism

A vertical track nonlinear energy sink

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Applied Mathematics and Mechanics(English Edition) 2024年第6期45卷 931-946页

作者： meng LI Hu DING Shanghai Key Laboratory of Mechanics in Energy Engineering School of Mechanics and Engineering ScienceShanghai Frontier Science Center of MechanoinformaticsShanghai UniversityShanghai 200444China

Eliminating the effects of gravity and designing nonlinear energy sinks(NESs)that suppress vibration in the vertical direction is a challenging task with numerous damping requirements.In this paper,the dynamic design of a vertical track nonlinear energy sink(VTNES)with zero linear stiffness in the vertical direction is proposed and realized for the first time.The motion differential equations of the VTNES coupled with a linear oscillator(LO)are established.With the strong nonlinearity considered of the VTNES,the steady-state response of the system is analyzed with the harmonic balance method(HBM),and the accuracy of the HBM is verified numerically.On this basis,the VTNES prototype is manufactured,and its nonlinear stiffness is identified.The damping effect and dynamic characteristics of the VTNES are studied theoretically and experimentally.The results show that the VTNES has better damping effects when strong modulation responses(SMRs)occur.Moreover,even for small-amplitude vibration,the VTNES also has a good vibration suppression effect.To sum up,in order to suppress the vertical vibration,an NES is designed and developed,which can suppress the vertical vibration within certain ranges of the resonance frequency and the vibration intensity.

关键词： track nonlinear energy sink(TNES) vertical direction gravity nonlinear stiffness harmonic balance method(HBM) vibration control

Nested Saturated Control of Uncertain Complex Cascade Systems Using Mixed Saturation Levels

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IEEE/CAA Journal of Automatica Sinica 2024年第5期11卷 1163-1174页

作者： meng Li Zhigang Zeng Wuhan National Laboratory for Optoelectronics Wuhan 430074 School of Artificial Intelligence and Automation Huazhong University of Science and TechnologyWuhan 430074China School of Artificial Intelligence and Automation Huazhong University of Science and TechnologyWuhan 430074 Key Laboratory of Image Processing and Intelligent Control of Education Ministry of China Wuhan 430074China

This study addresses the problem of global asymptotic stability for uncertain complex cascade systems composed of multiple integrator systems and non-strict feedforward nonlinear systems. To tackle the complexity inherent in such structures, a novel nested saturated control design is proposed that incorporates both constant saturation levels and state-dependent saturation levels. Specifically, a modified differentiable saturation function is proposed to facilitate the saturation reduction analysis of the uncertain complex cascade systems under the presence of mixed saturation levels. In addition, the design of modified differentiable saturation function will help to construct a hierarchical global convergence strategy to improve the robustness of control design scheme. Through calculation of relevant inequalities, time derivative of boundary surface and simple Lyapunov function,saturation reduction analysis and convergence analysis are carried out, and then a set of explicit parameter conditions are provided to ensure global asymptotic stability in the closed-loop systems. Finally, a simplified system of the mechanical model is presented to validate the effectiveness of the proposed method.

关键词： method saturation differentiable

Adaptive admittance tracking control for interactive robot with prescribed performance

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Journal of Systems Engineering and Electronics 2024年第2期35卷 444-450页

作者： meng Qingrui LIN Yan School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100190China College of Electrical Engineering and Automation Shandong University of Science and TechnologyQingdao 266590China

An adaptive control approach is presented in this paper for tracking desired trajectories in interactive manipulators. The controller design incorporates prescribed performance functions (PPFs) to improve dynamic performance. Notably, the performance of the output error is confined in an envelope characterized by exponential convergence, leading to convergence to zero. This feature ensures a prompt response from admittance control and establishes a reliable safety framework for interactions. Simulation results provide practical insights,demonstrating the viability of the control scheme proposed in this paper.

关键词： prescribed performance admittance control adaptive control robots