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A probabilistic generative model for tracking multi-knowledge concept mastery probability

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Frontiers of Computer Science 2024年第3期18卷 155-170页

作者： Hengyu lIU Tiancheng ZHANG Fan lI Minghe YU ge YU School of Computer Science and Engineering Northeastern UniversityShenyang 110169China Software College Northeastern UniversityShenyang 110169China

Knowledge tracing aims to track students’knowledge status over time to predict students’future performance *** a real environment,teachers expect knowledge tracing models to provide the interpretable result of knowledge *** chain-based knowledge tracing(MCKT)models,such as Bayesian Knowledge Tracing,can track knowledge concept mastery probability over ***,as the number of tracked knowledge concepts increases,the time complexity of MCKT predicting student performance increases exponentially(also called explaining away problem).When the number of tracked knowledge concepts is large,we cannot utilize MCKT to track knowledge concept mastery probability over *** addition,the existing MCKT models only consider the relationship between students’knowledge status and problems when modeling students’responses but ignore the relationship between knowledge concepts in the same *** address these challenges,we propose an inTerpretable probAbilistiC generative model(TRACEd),which can track students’numerous knowledge concepts mastery probabilities over *** solve explain away problem,we design long and short-term memory(lSTM)-based networks to approximate the posterior distribution,predict students’future performance,and propose a heuristic algorithm to train lSTMs and probabilistic graphical model *** better model students’exercise responses,we proposed a logarithmic linear model with three interactive strategies,which models students’exercise responses by considering the relationship among students’knowledge status,knowledge concept,and *** conduct experiments with four real-world datasets in three knowledge-driven *** experimental results show that TRACEd outperforms existing knowledge tracing methods in predicting students’future performance and can learn the relationship among students,knowledge concepts,and problems from students’exercise *** also conduct several case *** case studies show that

关键词： probabilistic graphical model deep learning knowledge tracing learner modeling

Preparation and Structure-Property Regulation Mechanism of Reversible Thermochromic Polydiacetylene

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Chinese Journal of Polymer Science 2024年第8期42卷 1111-1121页

作者： Zhi-Qing ge Shuo Yan Zu-Xiong Pan Shan lei Xuan-Zhi Mao Chu Zhao Mo-Zhen Wang Xue-Wu ge Key laboratory of Precision and Intelligent Chemistry Department of Polymer Science and EngineeringUniversity of Science and Technology of ChinaHefei 230026China Marshall laboratory of Biomedical Engineering International Cancer CenterLaboratory of Evolutionary Theranostics(LET)School of Biomedical EngineeringShenzhen University Medical SchoolShenzhen UniversityShenzhen 518055China Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China

The thermochromic mechanism and the structure-property regulation principle of reversible thermochromic polydiacetylene(PdA)materials have always been a challenging *** this work,a series of diacetylene monomers(m-PCdA)containing phenyl and amide or carboxyl groups were synthesized from 10,12-pentacosadiynoic acid(PCdA)through the esterification or amidation *** effects of the number and the distribution of the functional groups in m-PCdA molecules on their solid-state polymerization capability,and the thermochromic mechanism of their corresponding polymers(m-PdA)were investigated and discussed in *** results show that the m-PCdA monomers containing both benzene ring and groups that can form hydrogen bonding interactions have strong intermolecular interaction,and are easy to carry out the solid phase polymerization under 254-nm UV irradiation to obtain the corresponding new thermochromic m-PdA *** thermochromic behavior of m-PdA depends on its melting *** initial color-change temperature(blue to red)is determined by the onset melting tem perature,and the temperature range in which reversible color recovery can be achieved by repeat heating-cooling treatment is determined by its melting *** to the proposed thermochromic mechanism of PdA,various new PdA materials with precise thermochromic temperatu res and reversible thermochromic temperature ra nges can be designed and synthesized through the appropriate introduction of benzene ring and groups that can form hydrogen bonding interactions into the molecular structure of linear diacetylene *** work provides a perspective to the precise molecular structure design and the property regulation of the reversible thermochromic PdA materials.

关键词： Polydiacetylene Thermochromism Hydrogen bonding Chemical modification

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Advances in understanding and managing celiac disease:Pathophysiology and treatment strategies

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World Journal of Gastroenterology 2024年第35期30卷 3932-3941页

作者： Hao-Jie ge Xu-lin Chen department of Burns The First Affiliated Hospital of Anhui Medical UniversityHefei 230022Anhui ProvinceChina

In this editorial,we comment on an article published in the recent issue of the World Journal of *** disease(Ced)is a disease occurring in genetically susceptible individuals,which is mainly characterized by gluten intolerance in the small intestine and clinical symptoms such as abdominal pain,diarrhea,and ***,patients often need a lifelong gluten-free diet,which greatly affects the quality of life and expenses of *** gold standard for diagnosis is intestinal mucosal biopsy,combined with serological and genetic *** present,the lack of safe,effective,and satisfactory drugs for Ced is mainly due to the complexity of its pathogenesis,and it is difficult to find a perfect target to solve the multi-level needs of *** this editorial,we mainly review the pathological mechanism of Ced and describe the current experimental and improved drugs for various pathological aspects.

关键词： Celiac disease Gluten-free diet Pathology Human leukocyte antigen Immunotherapy Treatment Aspergillus niger prolyl endoprotease

role of Vickers ligament in the Pathogenesis of Madelung deformity

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Current Medical Science 2024年第4期44卷 735-740页

作者： ge XIONG Wei ZHENG li-hua GONG department of Hand Surgery Beijing Jishuitan HospitalCapital Medical UniversityBeijing 100035China department of Pathology Beijing Jishuitan HospitalCapital Medical UniversityBeijing 100035China

Objective The Vickers ligament is thought to hinder the growth of palmar ulnar radius by tethering the lunate to the radius,leading to Madelung *** purpose of this study was to clarify the nature of the Vickers ligament and investigate its pathogenesis in Madelung deformities based on our observation of the Vickers *** All 22 patients(33 wrists)with Madelung deformities treated surgically between 2018 and 2022 were *** diagnosis was confirmed radiographically in all *** three-dimensional computed tomography(3d-CT)data of 16 patients(19 wrists)were *** resonance imaging(MRI)data were available for 9 patients(14 wrists).Wrist arthroscopy was used in 4 *** Vickers ligament was resected and submitted for histopathological examination in 8 *** outcomes,3d-CT,MRI,arthroscopy,surgical findings,and histopathology of the Vickers ligament were *** The 3d-CT revealed that the Vickers ligament originated in the metaphysis and formed a metaphyseal defect at the palmar ulnar *** the sequential MR coronal images,the Vickers ligament could be divided into 3 branches,extending to the lunate,triquetrum and ulnar *** and surgical findings revealed that the nature of the Vickers ligament was the stretched palmar ligament of the *** histopathology results revealed ligamentous tissue and fibrocartilaginous metaplasia with a structure similar to that of the triangular fibrocartilage complex(TFCC).Conclusions The Vickers ligament is not a separate aberrant *** nature of the Vickers ligament is a combination of the stretched TFCC ligament(palmar radioulnar ligament,ulnotriquetral ligament and ulnolunate ligament)and radiolunate *** possible pathogenesis of Madelung deformity might be focal early epiphyseal closure at the middle part of the sigmoid notch,which leads to focal growth retardation of the radius and pulls palmar ligaments proximally to for

关键词： Vickers ligament Madelung deformity pathogenesis computed tomography magnetic resonance imaging

Cobalt(Ⅲ)hydride HAT mediated enantioselective intramolecular hydroamination access to chiral pyrrolidines

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Science China Chemistry 2024年第6期67卷 2002-2008页

作者： Qi Meng Tao Qin Huanran Miao ge Zhang Qian Zhang Jilin Province Key laboratory of Organic Functional Molecular design&Synthesis Department of ChemistryNortheast Normal UniversityChangchun130024China State Key laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai200032China

Enantioenriched pyrrolidines and derivatives are ubiquitous substructures in compounds of importance to medicinal and biological ***,we report an efficient cobalt-catalyzed intramolecular asymmetric hydroamination reaction that produces chiral pyrrolidines with good to excellent yield and *** with previously reported radicalinvolved methodologies for enantioenriched pyrrolidines,these conditions feature two elegant versatilities,enabling(1)the use of cobalt-catalyzed hydrogen atom transfer(HAT)to generate organocobalt intermediates that bring radical reaction to organometallic chemistry,and(2)enantioselective intramolecular C-N bond forging through an S_(N)2-like displacement involving dynamic kinetic resolution(dKR).This approach provides a new alternative and efficient methodology for enantioselective radical-involved C-N bond construction that can be used in the synthesis of both chiral pyrrolidines and homologous nitrogen heterocycles.

关键词： asymmetric catalysis radical hydroamination cobalt catalysis hydrogen atom transfer

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Energy consumption optimization for edge computing-supported cellular networks based on optimal transport theory

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Science China(Information Sciences) 2024年第2期67卷 201-218页

作者： Xiangyu lV Xiaohu ge Yi ZHONG Qiang lI Yong XIAO School of Electronic Information and Communications Huazhong University of Science and Technology

With advancements in mobile communication technologies, there have been multiple user device(Ud) connections to cellular networks. Because of changes in the spatial distribution of Uds and application requirements, the traditional offloading mechanism based on the nearest distance will result in heavy loads for some base stations(BSs). Because there is a high-order relationship between the energy consumption of the BS processing tasks and the number of computing tasks, the traditional offloading mechanism will result in high energy consumption, and Ud’s offloading decision must be dynamically adjusted. The offloading decision of Uds is optimized based on detailed information about various parameters associated with a network from the standpoint of distribution. This information includes details regarding the spatial distribution of Uds,application requirements, and the offloading period of computing tasks. Based on optimal transport theory,an energy consumption optimization algorithm is suggested to lower the total amount of energy consumed by the offloading process of Uds’ computing tasks by reasonably planning the offloading BSs of the Uds in the networks. The simulation results show that the proposed offloading mechanism based on energy consumption optimization reduces the total energy consumption of the offloading process by 28.09% when compared to the traditional offloading mechanism, and the traffic managed by each BS is balanced.

关键词： optimal transport theory edge computing energy consumption reduction dynamic voltage frequency scaling

Performance and environmental impacts of deep foundation excavation in soft soils:A field and modeling-based case study in Nanjing,China

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Underground Space 2024年第5期18卷 218-238页

作者： Chenhe ge Meng Yang Pengfei li Mingju Zhang Zhonghao Zhang Key laboratory of Urban Security and disaster Engineering Ministry of EducationBeijing University of TechnologyBeijing 100124China China Construction Second Engineering Bureau ltd. Beijing 100070China The Third Construction Engineering Company ltd.of China Construction Second Engineering Bureau Beijing 100070China

This paper focuses on the performance of a braced deep excavation in soft soil based on field monitoring and numerical *** tests were conducted to determine the soil parameters used in the modified Cam–Clay(MCC)*** field monitoring means were adopted and a three-dimensional model was *** and temporal effects induced by the excavation are investigated for the deep-large foundation pit in soft *** characteristics of the enclosure structure and the surrounding environment throughout the excavation process are *** behaviors of diaphragm walls,columns,the maximum wall deflection rate,ground surface settlement,and utility pipelines were focused on and investigated during the whole excavation ***,the axial forces of the internal supports are *** on the measured and simulated data,the following main conclusions were obtained:the numerical simulation results are in good agreement with the measured values,which proves the accuracy of the model parameters;the wall and the ground surface showed the maximum displacement increment at stage 9,which was a coupled product of the"creep effect"of the soft soil in Nanjing,China and the"depth effect"of the excavation;as the excavation progressed,the ground settlement changed from a"rising"to a"spoon-shaped"trend,dvm was measured betweenδ_(vm)=0.0686%H andδ_(vm)=0.1488%H;the rebound deformation curve of the pit bottom was corrugated,and the depth of disturbance of the pit bottom after the completion of soil unloading was 2–3 times the excavation depth;the closer the pipeline is to the corner of the pit,the less the excavation process will affect the settlement of the pipeline and the less the obvious pit corner effect will occur;the support strength of the buttress and the longest corner brace should be strengthened during the actual construction process to ensure the stability of the foundation deformation.

关键词： deep excavation Modified Cam-Clay deformation characteristics Creep effect Corner effect

A novel tunnel waterproof-drainage system based on double-bonded waterproofing materials and its seepage characteristics

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Frontiers of Structural and Civil Engineering 2024年第9期18卷 1321-1336页

作者： Xiaohe SUN Chenghua SHI Guoqing XIAO Yangyang ge Chengyong CAO School of Civil Engineering Central South UniversityChangsha 410075China PowerChina ZhongNan Engineering Corporation limited Changsha 410014China State Key laboratory of Special Functional Waterproof Materials Beijing Oriental Yuhong Waterproof Technology Co.Ltd.Beijing 101111China College of Civil and Transportation Engineering Shenzhen UniversityShenzhen 518060China

double-bonded spray membrane waterproofing materials have excellent waterproofing performance and can improve the load-bearing capacity of tunnel linings,leading to an increasing global ***,due to the double-bonded capability of spray membrane materials,traditional interlayer drainage methods cannot be *** limitation makes it difficult to use them in drainage-type tunnels,significantly restricting their range of *** this regard,a novel tunnel waterproof-drainage system based on double-bonded spray membrane materials was proposed in this *** proposed drainage system primarily comprises upper drainage sheets and bottom drainage blind pipes,both located in the tunnel circumferential direction,as well as longitudinal drainage pipes within the ***,numerical calculation methods are employed to analyze the seepage characteristics of this system,revealing the water pressure distribution around the *** results indicate that in the novel waterproof-drainage system,the water pressure in the secondary lining exhibits a“mushroom-shaped”distribution in the circumferential direction,while the water pressure in the longitudinal direction exhibits a“wave-like”***,comparative results with other waterproof-drainage systems indicate that under typical working conditions with a water head of 160 m and a rock permeability coefficient of 10^(−6)m/s,the maximum water pressure in the secondary lining of the novel waterproof-drainage system is 0.6 *** represents a significant reduction compared to fully encapsulated waterproofing and traditional drainage systems,which respectively reduce the water pressure by 65%and 30%.The applicability analysis of the double-bonded waterproofing and drainage system reveals that it can reduce at least 40%of the static water pressure in any groundwater *** novel drainage system provides a valuable reference for the application of double-bonded spray membr

关键词： tunnel drainage spray-applied waterproofing membrane numerical simulation water pressure

Multi-objective constructal design for quadrilateral heat generation body based on thermal-entransy theory and NSGA-Ⅱ

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Science China(Technological Sciences) 2024年第9期67卷 2777-2786页

作者： CHEN lingen ZHU HongWei ge Yanlin SHI ShuangShuang FENG HuiJun Institute of Thermal Science and Power Engineering Wuhan Institute of TechnologyWuhan 430205China Hubei Provincial Engineering Technology Research Center of Green Chemical Equipment Wuhan 430205China School of Mechanical Electrical EngineeringWuhan Institute of TechnologyWuhan 430205China

Based on thermal-entransy theory, the multi-objective constructal design of quadrilateral heat generation body(HGB) with similar shapes of leaves is studied further. The relationship between the aspect ratio of quadrilateral HGB and average temperature difference based on thermal-entransy dissipation is compared with that between the aspect ratio of quadrilateral HGB and the maximum temperature difference(MTd). The relationship between a composite function, consisting of linear weighting sum of the average temperature difference and MTd, and aspect ratio is obtained, and the optimal aspect ratios under minimum composite function with different weighting coefficients are obtained. Using the NSGA-Ⅱ algorithm, the Pareto frontier containing a series of compromise results of average temperature difference and MTd is obtained, and optimization results are compared using the deviation index. There is no aspect ratio to make both MTd and average temperature difference reach the minimum, and the optimal aspect ratio under the minimum MTd is smaller than that under the minimum average temperature difference. The optimal aspect ratio is obtained by making the composite function reach the minimum, and the optimal aspect ratios obtained by minimizing the composite function with different weighting coefficients are different. Compared with the construct of the initial design, the value of the composite function with optimal construct decreases by 1.9%, and the aspect ratio of the quadrilateral HGB decreases by 9.1%. The average temperature difference with the optimal construct increases by 2.1%, and the MTd with the optimal construct decreases by 5.6%. The deviation index under multi-objective optimization is smaller than that under single-objective optimization, and the obtained construct has better comprehensive thermal conductivity. Compared with TOPSIS and lINMAP decision-making methods, the average temperature difference with composite function optimization increases by 0.5

关键词： thermal-entransy theory constructal theory heat conduction quadrilateral heat generation body composite function NSGA-Ⅱ

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