检索结果-南通市图书馆

Role based access control design using Triadic concept analysis

在线全文

学校读者我要写书评

暂无评论

Journal of Central South University 2016年第12期23卷 3183-3191页

作者： ch.Aswani Kumar S.chandra Mouliswaran li Jin-hai C.chandrasekar School of Information Technology & Engineering VIT University Faculty of Science Kunming University of Science and Technology Department of Computer Science Periyar University

Role based access control is one of the widely used access control *** are investigations in the literature that use knowledge representation mechanisms such as formal concept analysis(FCA),description logics,and Ontology for representing access control ***,while using FCA,investigations reported in the literature so far work on the logic that transforms the three dimensional access control matrix into dyadic formal *** transformation is mainly to derive the formal concepts,lattice structure and implications to represent role hierarchy and constraints of *** this work,we propose a methodology that models RBAC using triadic FCA without transforming the triadic access control matrix into dyadic formal *** discussion is on two lines of *** present how triadic FCA can provide a suitable representation of RBAC policy and we demonstrate how this representation follows role hierarchy and constraints of RBAC on sample healthcare network available in the literature.

关键词： access control concept lattice role based access control role hierarchy triadic context triadic concept analysis

Isomeric structures, isomerization and decomposition of silylenoids H2SiMX(MX=KF,KCl liBr,naBr and KBr)

在线全文

学校读者我要写书评

暂无评论

chinese Journal of chemistry 1995年第6期13卷 481-486页

作者： Feng, DC Feng, SY Deng, ch SHAnDOnG UnIV INST THEORET CHEMSHANDONG 250100PEOPLES R CHINA

The isomeric structures, isomerization and decomposition of silylenoids H(2)SiMX (MX=KF, KCl, liBr, naBr and KBr) have been investigated by ab initio molecular orbital theory. These silylenoids have four kinds of very similar equilibrium structures. The three-membered ring and p-complex structures should be stable and experimentally detectable. The lifetime of sigma-complex and tetrahedral structures would be very short and experimentally undetectable.

关键词： silylenoids H(2)SiMX isomeric structures isomerization decomposition

Asymptotic periodic solutions of some generalized Burgers equations

在线全文

学校读者我要写书评

暂无评论

Applied Mathematics(A Journal of chinese Universities) 2018年第4期33卷 390-408页

作者： Smriti nath ch.Srinivasa Rao Department of Mathematics Indian Institute of Technology Madras

In this paper, we construct asymptotic periodic solutions of some generalized Burgers equations using a perturbative approach. These large time asymptotics(constructed) are compared with relevant numerical solutions o... 详细信息

关键词： periodic solution large time asymptotics generalized Burgers equations

Research on Stock Price Prediction Method Based on the GAn-LSTM-Attention Model

在线全文

学校读者我要写书评

暂无评论

Computers, Materials & Continua 2025年第1期82卷 609-625页

作者： Peng li Yanrui Wei lili Yin College of Computer Science and Technology Harbin University of Science and TechnologyHarbin150006China

Stock price prediction is a typical complex time series prediction problem characterized by dynamics,nonlinearity,and *** paper introduces a generative adversarial network model that incorporates an attention mechanism(GAn-LSTM-Attention)to improve the accuracy of stock price ***,the generator of this model combines the Long and Short-Term Memory network(LSTM),the Attention Mechanism and,the Fully-Connected Layer,focusing on generating the predicted stock *** discriminator combines the Convolutional neural network(Cnn)and the Fully-Connected Layer to discriminate between real stock prices and generated stock ***,to evaluate the practical application ability and generalization ability of the GAn-LSTM-Attention model,four representative stocks in the United States of America(USA)stock market,namely,Standard&Poor’s 500 Index stock,Apple Incorporatedstock,AdvancedMicroDevices Incorporatedstock,and Google Incorporated stock were selected for prediction experiments,and the prediction performance was comprehensively evaluated by using the three evaluation metrics,namely,mean absolute error(MAE),root mean square error(RMSE),and coefficient of determination(R2).Finally,the specific effects of the attention mechanism,convolutional layer,and fully-connected layer on the prediction performance of the model are systematically analyzed through ablation *** results of experiment show that the GAn-LSTM-Attention model exhibits excellent performance and robustness in stock price prediction.

关键词： Stock price prediction generative adversarial network attention mechanism time-series prediction

Brain endothelial cyclic GMP-AMP synthase(cGAS)-stimulator of interferon genes(STInG)signaling pathway in aging and neurodegeneration

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

neural Regeneration Research 2025年第7期20卷 2005-2007页

作者： Bryan Sun Lulin li Jian Luo Palo Alto Veterans Institute for Research VA Palo Alto Health Care SystemPalo AltoCAUSA Polytrauma System of Care VA Palo Alto Health Care SystemPalo AltoCAUSA

The cyclic GMP-AMP synthase(cGAS)-stimulator of interferon genes(STInG)signaling pathway has emerged as a key mediator of *** current studies primarily attribute its effects to neurons and glial cells,emerging research suggests that cGAS-STInG signaling may play a critical role in cerebral vasculature,particularly in brain endothelial ***,studying the role 7of inflammation caused by the cGAS-STInG pathway in brain endothelial cells could provide a more comprehensive understanding of neuroinflammatory disease and new avenues for therapeutic ***,we review the multifaceted role of global cGAS-STInG signaling in various neurological and neuroinflammatory diseases and the potential contribution of cGAS-STInG in brain endothelial cells.

关键词： stimulator interferon inflammation

Bounded type Siegel disks of finite type maps with few singular values Dedicated to the Memory of Professor Lei Tan

在线全文

学校读者我要写书评

暂无评论

Science china Mathematics 2018年第12期61卷 2139-2156页

作者： Arnaud chéritat Adam Lawrence Epstein CnRS Institut de Mathematiques de ToulouseUniversite Paul SabatierToulouse F-31062France Mathematics Institute University of WarwickCoventry CV47ALUK

Let U be an open subset of the Riemann sphere C. We give sufficient conditions for which a finite type map f : U →C with at most three singular values has a Siegel disk compactly contained in U and whose boundary is a quasicircle containing a unique critical point. The main tool is quasiconformal surgery à la Douady-Ghys-Herman-(S′)wia tek. We also give sufficient conditions for which, instead, ? has not compact closure in U. The main tool is the Schwarzian derivative and area inequalities à la Graczyk-(S′)wia tek.

关键词： Siegel disks quasicircles quasiconformal surgery Schwarzian derivative

Impacts of PI3K/protein kinase B pathway activation in reactive astrocytes: from detrimental effects to protective functions

在线全文

学校读者我要写书评

暂无评论

neural Regeneration Research 2025年第4期20卷 1031-1041页

作者： Ramón Pérez-núñez María Fernanda González Ana María Avalos lisette Leyton Cellular Communication Laboratory Programa de Biología Celular y MolecularCenter for Studies on ExerciseMetabolism and Cancer(CEMC)Instituto de Ciencias Biomédicas(ICBM)Facultad de MedicinaUniversidad de ChileSantiagoChile Advanced Center for chronic Diseases(ACCDiS) Faculty of Chemical and Pharmaceutical Sciences&Faculty of MedicineUniversidad de ChileSantiagoChile Instituto de Ciencias Biomédicas Facultad de Ciencias de la SaludUniversidad Autónoma de ChileSantiagoChile

Astrocytes are the most abundant type of glial cell in the central nervous *** injury and inflammation,astrocytes become reactive and undergo morphological and functional *** on their phenotypic classification as A1 or A2,reactive astrocytes contribute to both neurotoxic and neuroprotective responses,***,this binary classification does not fully capture the diversity of astrocyte responses observed across different diseases and *** analysis has revealed that reactive astrocytes have a complex landscape of gene expression profiles,which emphasizes the heterogeneous nature of their *** actively participate in regulating central nervous system inflammation by interacting with microglia and other cell types,releasing cytokines,and influencing the immune *** phosphoinositide 3-kinase(PI3K)/protein kinase B(AKT)signaling pathway is a central player in astrocyte reactivity and impacts various aspects of astrocyte behavior,as evidenced by in silico,in vitro,and in vivo *** astrocytes,inflammatory cues trigger a cascade of molecular events,where nuclear factor-κB serves as a central mediator of the pro-inflammatory ***,we review the heterogeneity of reactive astrocytes and the molecular mechanisms underlying their *** highlight the involvement of various signaling pathways that regulate astrocyte reactivity,including the PI3K/AKT/mammalian target of rapamycin(mTOR),αvβ3 integrin/PI3K/AKT/connexin 43,and notch/PI3K/AKT *** targeting the inactivation of the PI3K/AKT cellular signaling pathway to control reactive astrocytes and prevent central nervous system damage,evidence suggests that activating this pathway could also yield beneficial *** dual function of the PI3K/AKT pathway underscores its complexity in astrocyte reactivity and brain function *** review emphasizes the importance of employing astrocyte-exclusive models to underst

关键词： inflammation integrins neuroprotective neurotoxic phosphatidylinositol 3-kinase reactive astrocytes signal transduction Thy-1(CD90)

Modifications of ALPPS–from complex to more complex or from complex to less complex operations

在线全文

学校读者我要写书评

暂无评论

Hepatobiliary & Pancreatic Diseases International 2017年第4期16卷 346-352页

作者： Wan Yee Lau Eric ch Lai Faculty of Medicine The Chinese University of Hong KongShatinNew TerritoriesHong Kong SARChina Department of Surgery Pamela Youde Nethersole Eastern HospitalHong Kong SARChina

BACKGROUnD: Associating liver partition and portal vein ligation for staged hepatectomy (ALPPS) has recently been developed to induce rapid liver hypertrophy to reduce the chance of post-hepatectomy liver failure in patients with borderline or insufficient future liver remnant. ALPPS is still in an early developmental stage and its techniques have not been standardized. This study aimed to review the technical modifications of the conventional ALPPS procedure. DATA SOURCES: Studies were identified by searching MEDlinE and PubMed for articles published from January 2007 to December 2016 using the keywords 'associating liver partition and portal vein ligation for staged hepatectomy' and 'ALPPS'. Additional articles were identified by a manual search of references from key articles. RESULTS: There have been a lot of modifications of the conventional ALPPS. These are classified as: (1) modifications aiming to improve surgical results; (2) modifications aiming to expand surgical indications; (3) salvage ALPPS; (4) ALPPS using the minimally invasive approach. Some of these modifications have made the conventional ALPPS procedure to become even more complex, although there have also been other attempts to make the procedure less complex. The results of most of these modifications have been reported in small case series or case reports. We need better well-designed studies to establish the true roles of these modifications. However, it is interesting to see how this conventional ALPPS procedure has evolved since its introduction. COnCLUSIOnS: There is a trend for the use of minimally invasive procedure in the phase 1 or 2 of the conventional ALPPS procedure. Some of these modifications have expanded the use of ALPPS in patients who have been considered to have unresectable liver tumors. The long-term oncological outcomes of these modifications are still unknown.

关键词： associating liver partition and portal vein ligation for stage hepatectomy hepatocellular carcinoma hepatectomy liver metastasis portal vein embolization

Fe3O4 nanoparticles impregnated eggshell as a novel catalyst for enhanced biodiesel production

在线全文

学校读者我要写书评

暂无评论

chinese Journal of chemical Engineering 2019年第11期27卷 2835-2843页

作者： ch.ch.ngakham Asha David V.Sajith School of nano Science and Technology National Institute of Technology CalicutIndia Malabar christian College CalicutIndia

Biodiesel is a green fuel which can replace diesel while addressing various issues such as scarcity of hydrocarbon fuels and environmental pollution to an extent. The high production cost of biodiesel and the recovery of the catalyst after the transesterification process are the major challenges to be addressed in biodiesel production. In the present work, a cheap and promising solid base oxide catalyst was synthesized from chicken eggshell by calcination at 900 ℃ forming catalyst eggshells(CES) and was impregnated with the nanomagnetic material(Fe3O4) to obtain Fe3O4 loaded catalytic eggshell(CES–Fe3O4). Fe3O4 nanomaterials were synthesized by co-precipitation method and were loaded in catalytic eggshell by sonication, for better recovery of the catalyst after transesterification process. CES–Fe3O4 material was characterized by Thermogravimetric analysis, X-ray diffraction, Fourier transform infrared spectroscopy, a vibrating-sample magnetometer, Brunauer-Emmett-Teller, Dynamic light scattering, and Scanning electron microscopy. Biodiesel was synthesized by transesterification of Pongamia pinnata raw oil with 1:12 oil to methanol molar ratio and 2 wt% catalyst loading for 2 h at a temperature of 65 ℃ and yields were compared. The reusability of the catalyst was studied by the transesterification of the raw oil and its catalytic activity was found to be retained up to 7 cycles with a yield of 98%.

关键词： Catalyst Biodiesel nanoparticles Fe3O4 Impregnation Transesterification