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Adaptive coupled synchronization of non-autonomous systems in ring networks 被引量:1
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作者 过榴晓 徐振源 胡满峰 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第3期836-841,共6页
The adaptive coupled synchronization method for non-autonomous systems is proposed. This method can avoid estimating the value of coupling coefficient. Under the uniform Lipschitz assumption, we derive the asymptotica... The adaptive coupled synchronization method for non-autonomous systems is proposed. This method can avoid estimating the value of coupling coefficient. Under the uniform Lipschitz assumption, we derive the asymptotical synchronization for a general coupling ring network with N identical non-autonomous systems~ even when N is large enough. Strict theoretical proofs are given. Numerical simulations illustrate the effectiveness of the present method. 展开更多
关键词 non-autonomous system adaptive synchronization chaotic synchronization ring net-works
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The Kemeny’s Constant and Spanning Trees of Hexagonal Ring Network
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作者 Shahid Zaman Ali N.A.Koam +1 位作者 Ali Al Khabyah Ali Ahmad 《Computers, Materials & Continua》 SCIE EI 2022年第12期6347-6365,共19页
Spanning tree(τ)has an enormous application in computer science and chemistry to determine the geometric and dynamics analysis of compact polymers.In the field of medicines,it is helpful to recognize the epidemiology... Spanning tree(τ)has an enormous application in computer science and chemistry to determine the geometric and dynamics analysis of compact polymers.In the field of medicines,it is helpful to recognize the epidemiology of hepatitis C virus(HCV)infection.On the other hand,Kemeny’s constant(Ω)is a beneficial quantifier characterizing the universal average activities of a Markov chain.This network invariant infers the expressions of the expected number of time-steps required to trace a randomly selected terminus state since a fixed beginning state si.Levene and Loizou determined that the Kemeny’s constant can also be obtained through eigenvalues.Motivated by Levene and Loizou,we deduced the Kemeny’s constant and the number of spanning trees of hexagonal ring network by their normalized Laplacian eigenvalues and the coefficients of the characteristic polynomial.Based on the achieved results,entirely results are obtained for the M鯾ius hexagonal ring network. 展开更多
关键词 Matrix Analysis hexagonal ring network Kemeny’s constant Spanning tree
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Ring Network Technology for Carrier Ethernet
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作者 Zhang Yongjun,Yao Yu,Gu Wanyi(Key Laboratory of Optical Communication and Lightwave Technologies,Ministry of Education,Beijing University of Posts and Telecommunications,Beijing 100876,P.R.China) 《ZTE Communications》 2009年第1期21-24,共4页
The fast development of IP services forces the traffic flow in the networks to move gradually from Time Division Multiplexing(TDM) services to packet data services.To adapt to the change,low-cost Ethernet technologies... The fast development of IP services forces the traffic flow in the networks to move gradually from Time Division Multiplexing(TDM) services to packet data services.To adapt to the change,low-cost Ethernet technologies are introduced into the Metropolitan Area Network(MAN).Ring network control protocols and ring network protection technologies are applied to guarantee manageability and reliability required in the telecom networks.The Ethernet Ring Protection(ERP) and Resilient Packet Ring(RPR) are two different ring protection technologies.The Transport Multi-Protocol Label Switching(T-MPLS) network uses the T-MPLS Shared Protection Ring(TM-SPRing) technology to provide ring protection.Carriers can expand the protection as needed and use appropriate ring technologies to meet the requirements of Carrier Ethernet(CE). 展开更多
关键词 MPLS 电信级以太网 RPR ring network Technology for Carrier Ethernet NODE link 城域网 市域网 计算机网络 EAPS
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Eigenvalue Spectrum and Synchronizability of Double-Layer Directed Ring Networks
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作者 Ping Wu Zhen Jia +1 位作者 Feimei Yang Jiaquan Huang 《Journal of Applied Mathematics and Physics》 2021年第12期3067-3087,共21页
The synchronizability of multiplex undirected regular networks has been intensively studied based on the study of the synchronizability of single-layer networks. However, most real networks are characterized by some d... The synchronizability of multiplex undirected regular networks has been intensively studied based on the study of the synchronizability of single-layer networks. However, most real networks are characterized by some degree of directionality. So multiplex directed networks can better explain the synchronizability phenomenon. Here, based on the theory of master stability function (MSF), we study the eigenvalue spectrum and synchronizability of double-layer inter-layer directed ring networks (Networks-A) and double-layer intra-layer directed ring networks (Networks-B). The eigenvalue spectrum of the supra-Laplacian matrix of the networks is rigorously derived, and the influence of the networks structure parameters on the network’s synchronizability is analyzed. The correctness of the theory is further verified by numerical simulation analysis. Finally, the synchronizability of four kinds of double-layer ring networks with different coupling modes, namely, Networks-A, Networks-B, Networks-C (double-layer undirected ring networks), and Networks-D (double-layer undirected inter-layer random-added-edge ring networks), is compared and the results can provide guidance for constructing the optimal synchronization network. 展开更多
关键词 Double-Layer ring networks Eigenvalue Spectrum SYNCHRONIZABILITY
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Synchronizability of Two-Layer Cluster Ring Networks 被引量:1
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作者 Yang Deng Zhen Jia Lin Liao 《Communications and Network》 2019年第2期35-51,共17页
Multilayer network is a frontier direction of network science research. In this paper, the cluster ring network is extended to a two-layer network model, and the inner structures of the cluster blocks are random, smal... Multilayer network is a frontier direction of network science research. In this paper, the cluster ring network is extended to a two-layer network model, and the inner structures of the cluster blocks are random, small world or scale-free. We study the influence of network scale, the interlayer linking weight and interlayer linking fraction on synchronizability. It is found that the synchronizability of the two-layer cluster ring network decreases with the increase of network size. There is an optimum value of the interlayer linking weight in the two-layer cluster ring network, which makes the synchronizability of the network reach the optimum. When the interlayer linking weight and the interlayer linking fraction are very small, the change of them will affect the synchronizability. 展开更多
关键词 Two-Layer CLUSTER ring network SYNCHRONIZABILITY INTERLAYER LINKING WEIGHT INTERLAYER LINKING FRACTION
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Performance Evaluation and Pseudo-Conservation Laws in Token Ring Network with Batch Arrivals and Limited Services
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作者 Ao, Zhigang Wang, Yaohua +1 位作者 Rong, Xianhui Qian, Shuhua 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1998年第2期61-69,共9页
This paper,using pseudo-conservation laws in cyclic-service systems, derives some expressions for the weighted sum of the mean waiting time token ring networks with exhaustive limitedservice policies on condition that... This paper,using pseudo-conservation laws in cyclic-service systems, derives some expressions for the weighted sum of the mean waiting time token ring networks with exhaustive limitedservice policies on condition that messages arrived with batch Poisson, and discusses boundary conditions. At the same time, the results of the token ring network with exhaustive and non-exhaustiveservice strategy are obtained. Finally the exact expression of mean waiting time in symmetric ringnetwork with same service strategy is given. 展开更多
关键词 ring network Performance evaluation Pseudo-conservation LAWS
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Design and Simulation of Ring Network-on-Chip for Different Configured Nodes
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作者 Arpit Jain Rakesh Kumar Dwivedi +3 位作者 Hammam Alshazly Adesh Kumar Sami Bourouis Manjit Kaur 《Computers, Materials & Continua》 SCIE EI 2022年第5期4085-4100,共16页
The network-on-chip(NoC)technology is frequently referred to as a front-end solution to a back-end problem.The physical substructure that transfers data on the chip and ensures the quality of service begins to collaps... The network-on-chip(NoC)technology is frequently referred to as a front-end solution to a back-end problem.The physical substructure that transfers data on the chip and ensures the quality of service begins to collapse when the size of semiconductor transistor dimensions shrinks and growing numbers of intellectual property(IP)blocks working together are integrated into a chip.The system on chip(SoC)architecture of today is so complex that not utilizing the crossbar and traditional hierarchical bus architecture.NoC connectivity reduces the amount of hardware required for routing and functions,allowing SoCs with NoC interconnect fabrics to operate at higher frequencies.Ring(Octagons)is a direct NoC that is specifically used to solve the scalability problem by expanding each node in the shape of an octagon.This paper discusses the ring NoC design concept and its simulation in Xilinx ISE 14.7,as well as the communication of functional nodes.For the field-programmable gate array(FPGA)synthesis,the performance of NoC is evaluated in terms of hardware and timing parameters.The design allows 64 to 256 node communication in a single chip with‘N’bit data transfer in the ring NoC.The performance of the NoC is evaluated with variable nodes from 2 to 256 in Digilent manufactured Virtex-5 FPGA hardware. 展开更多
关键词 ring NoC FPGA synthesis nodes communication SoC design integrated synthesis environment
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Priority-Aware IP over Hierarchical WDM Ring Networks
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作者 Jih-Hsin Ho 《Computer Technology and Application》 2015年第2期70-75,共6页
WDM (wavelength division multiplexing) appears to be the solution of choice for providing a faster networking infrastructure that can meet the explosive growth of the Internet. It has the scalability problem with in... WDM (wavelength division multiplexing) appears to be the solution of choice for providing a faster networking infrastructure that can meet the explosive growth of the Internet. It has the scalability problem with increasing the access node numbers in WDM ring architecture, so we further propose the alternatives of hierarchical WDM ring architecture. Since the traditional IP provides the best effort service only, the issue of supporting IP packets with QoS (quality of Service) transfer has become a crucial issue for multimedia transmission. We do so by addressing the priority-aware QoS model. Finally present performance analysis multiple classes of hierarchical WDM ring networks. 展开更多
关键词 Hierarchical WDM ring priority-aware performance analysis.
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Impact of Alcian blue and periodic acid Schiff expression on the prognosis of gastric signet ring cell carcinoma
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作者 Juan Lin Zhu-Feng Chen +1 位作者 Guo-Dong Guo Xin Chen 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第3期687-698,共12页
BACKGROUND The Alcian blue(AB)and periodic acid Schiff(PAS)stains are representative mucus markers in gastric signet ring cell carcinoma(SRCC).They are low-cost special staining methods used to detect acidic mucus and... BACKGROUND The Alcian blue(AB)and periodic acid Schiff(PAS)stains are representative mucus markers in gastric signet ring cell carcinoma(SRCC).They are low-cost special staining methods used to detect acidic mucus and neutral mucus,respectively.However,the clinical importance of the special combined AB and PAS stain is unclear.AIM To investigate AB expression,PAS expression and the AB-to-PAS(A/P)ratio in gastric SRCC patients and to assess patient prognosis.METHODS Paraffin-embedded sections from 83 patients with gastric SRCC were stained with AB and PAS,and signet ring cell positivity was assessed quantitatively.Immuno-histochemical staining for Ki67,protein 53(P53)and human epidermal growth factor receptor 2(HER2)was performed simultaneously.The cancer-specific survival(CSS)rate was estimated via Kaplan-Meier analysis.Cox proportional hazards models were used for univariate and multivariate survival analyses.RESULTS Kaplan-Meier survival analysis revealed that the 3-year CSS rate was significantly greater in the high-PAS-expression subgroup than in the low-PAS-expression subgroup(P<0.001).The 3-year CSS rate in the A/P≤0.5 group was significantly greater than that in the A/P>0.5 group(P=0.042).Univariate Cox regression analysis revealed that the factors affecting prognosis included tumor diameter,lymph node metastasis,vessel carcinoma embolus,tumor stage,the A/P ratio and the expression of Ki67,P53 and the PAS.Cox multivariate regression analysis confirmed that low PAS expression[hazard ratio(HR)=3.809,95%confidence interval(CI):1.563-9.283,P=0.003]and large tumor diameter(HR=2.761,95%CI:1.086-7.020,P=0.033)were independent risk factors for poor prognosis.CONCLUSION A/P>0.5 is potentially a risk factor for prognosis,and low PAS expression is an independent risk factor in the prognosis of gastric SRCC.PAS expression and the A/P ratio could help in predicting the clinical prognosis of patients with SRCC. 展开更多
关键词 Alcian blue Periodic acid-Schiff PROGNOSIS GASTRIC Signet ring cell carcinoma
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Epidemiology and prognostic nomogram for locally advanced gastric signet ring cell carcinoma:A population-based study
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作者 Ze-Hao Yu Lei-Ming Zhang +2 位作者 Zhi-Qi Dai Meng-Na Zhang Si-Ming Zheng 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第6期2610-2630,共21页
BACKGROUND Gastric signet ring cell carcinoma(GSRC)represents a specific subtype of gastric cancer renowned for its contentious epidemiological features,treatment principles,and prognostic factors.AIM To investigate t... BACKGROUND Gastric signet ring cell carcinoma(GSRC)represents a specific subtype of gastric cancer renowned for its contentious epidemiological features,treatment principles,and prognostic factors.AIM To investigate the epidemiology of GSRC and establish an improved model for predicting the prognosis of patients with locally advanced GSRC(LAGSRC)after surgery.METHODS The annual rates of GSRC incidence and mortality,covering the years 1975 to 2019,were extracted from the Surveillance,Epidemiology,and End Results(SEER)database to explore the temporal trends in both disease incidence and mortality rates using Joinpoint software.The clinical data of 3793 postoperative LAGSRC patients were collected from the SEER database for the analysis of survival rates.The Cox regression model was used to explore the independent prognostic factors for overall survival(OS).The risk factors extracted were used to establish a prognostic nomogram.RESULTS The overall incidence of GSRC increased dramatically between 1975 and 1998,followed by a significant downward trend in incidence after 1998.In recent years,there has been a similarly optimistic trend in GSRC mortality rates.The trend in GSRC showed discrepancies based on age and sex.Receiver operating characteristic curves,calibration curves,and decision curve analysis for 1-year,3-year,and 5-year OS demonstrated the high discriminative ability and clinical utility of this nomogram.The area under the curve indicated that the performance of the new model outperformed that of the pathological staging system.CONCLUSION The model we established can aid clinicians in the early prognostication of LAGSRC patients,resulting in improved clinical outcomes by modifying management strategies and patient health care. 展开更多
关键词 Signet ring cell carcinoma Locally advanced gastric cancer Adjuvant chemotherapy NOMOGRAM EPIDEMIOLOGY Overall survival
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Colon signet-ring cell carcinoma with chylous ascites caused by immunosuppressants following liver transplantation:A case report
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作者 Ying Li Yang Tai Hao Wu 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第7期2343-2350,共8页
BACKGROUND Chylous ascites is caused by disruption of the lymphatic system,which is characterized by the accumulation of a turbid fluid containing high levels of triglycerides within the abdominal cavity.The two most ... BACKGROUND Chylous ascites is caused by disruption of the lymphatic system,which is characterized by the accumulation of a turbid fluid containing high levels of triglycerides within the abdominal cavity.The two most common causes are cirrhosis and tuberculosis,and colon signer ring cell carcinoma(SRCC)due to the use of immunosuppressants is extremely rare in cirrhotic patients after liver transplantation,making it prone to misdiagnosis and missed diagnosis.CASE SUMMARY A 52-year-old man who underwent liver transplantation and was administered with immunosuppressants for 8 months was admitted with a 3-month history of progressive abdominal distention.Initially,based on lymphoscintigraphy and lymphangiography,lymphatic obstruction was considered,and cystellar chyli decompression with band lysis and external membrane stripping of the lymphatic duct was performed.However,his abdominal distention was persistent without resolution.Abdominal paracentesis revealed allogenic cells in the ascites,and immunohistochemistry analysis revealed adenocarcinoma cells with phenotypic features suggestive of a gastrointestinal origin.Gastrointestinal endoscopy was performed,and biopsy showed atypical signet ring cells in the ileocecal valve.The patient eventually died after a three-month follow-up due to progression of the tumor.CONCLUSION Colon SRCC,caused by immunosuppressants,is an unusual but un-neglected cause of chylous ascites. 展开更多
关键词 Colonic signer ring cell carcinoma IMMUNOSUPPRESSANT Chylous ascites CIRRHOSIS Liver transplantation Case report
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Gastroesophageal signet ring cell carcinoma morbidity and mortality: A retrospective review
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作者 Megan Grinlinton Chris Furkert +2 位作者 Andrew Maurice Neville Angelo Michael Booth 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第6期1629-1636,共8页
BACKGROUND Upper gastrointestinal(GI)signet ring cell carcinomas(SRCC)confer a poor prognosis.The benefit of operative intervention for this patient group is contro-versial in terms of overall survival.AIM To investig... BACKGROUND Upper gastrointestinal(GI)signet ring cell carcinomas(SRCC)confer a poor prognosis.The benefit of operative intervention for this patient group is contro-versial in terms of overall survival.AIM To investigate factors relating to survival in patients with upper GI SRCC.METHODS A retrospective,tertiary,single-centre review of patients who were diagnosed with oesophageal,gastroesophageal junction and gastric SRCC was performed.The primary outcome was to compare mortality of patients who underwent operative management with those who had nonoperative management.Secon-dary outcomes included assessing the relationship between demographic and histopathological factors,and survival.RESULTS One hundred and thirty-one patients were included.The one-year survival for the operative group was 81%and for the nonoperative group was 19.1%.The five-year survival in the operative group was 28.6%vs 1.5%in the nonoperative group.The difference in overall survival between groups was statistically significant(HR 0.19,95%CI(0.13-0.30),P<0.001).There was no difference in survival when ad-justing for age,smoking status or gender.On multivariate analysis,patients who underwent surgical management,those with a lower stage of disease,and those with a lower Charlson Comorbidity Index(CCI)had significantly improved sur-vival.CONCLUSION Well-selected patients with upper GI SRCC appear to have reasonable medium-term survival following surgery.Offering surgery to a carefully selected patient group may improve the outcome for this disease. 展开更多
关键词 Signet ring cell carcinoma Gastric cancer Oesophageal cancer Poorly cohesive gastric cancer Diffuse gastric cancer
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Prognostic significance of preoperative lymphocyte to monocyte ratio in patients with signet ring gastric cancer 被引量:2
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作者 He-Li Liu Xiang Feng +4 位作者 Mi-Mi Tang Hai-Yan Zhou Huan Peng Jie Ge Ting Liu 《World Journal of Gastrointestinal Surgery》 SCIE 2023年第8期1673-1683,共11页
BACKGROUND The ratio of lymphocytes to monocytes(LMR)has been shown to be an effective predictor of gastric cancer prognosis.However,its predictive accuracy for signet ring gastric cancer is currently not well underst... BACKGROUND The ratio of lymphocytes to monocytes(LMR)has been shown to be an effective predictor of gastric cancer prognosis.However,its predictive accuracy for signet ring gastric cancer is currently not well understood.AIM To evaluate the prognosis predictive accuracy of preoperative LMR in signet ring gastric cancer.METHODS A total of 212 signet ring gastric cancer patients admitted at the Xiangya Hospital of Central South University,Department of Gastrointestinal Surgery,from January 2012 to December 2016 were enrolled in the study.The prognosis predictive accuracy of preoperative LMR was explored based on the area under the receiver operating characteristic.Factors that significantly affect the survival of patients were identified using single factor analysis,and those that were independently associated with signet ring gastric cancer were identified through multivariate analysis.RESULTS The results of the single factor analysis revealed a strong correlation between the survival of signet ring gastric cancer patients and several factors,including tumor invasion(χ^(2)=49.726;P<0.001),lymph node metastasis(χ^(2)=30.269;P<0.001),pTNM stage(χ^(2)=49.322;P<0.001),surgical approach(χ^(2)=8.489;P=0.004),age(t=-2.213;P<0.028),carcinoembryonic antigen(CEA)(Z=-3.265;P=0.001),platelet-to-lymphocyte ratio(Z=-2.196;P=0.028),LMR(Z=-2.226;P=0.026),ALB(t=3.284;P=0.001),prognostic nutritional index(t=-3.789;P<0.001)and FIB(Z=-3.065;P=0.002).Furthermore,the multivariate analysis further demonstrated that age(HR:0.563,95%CI:0.363-0.873),tumor invasion depth(HR:0.226,95%CI:0.098-0.520),pTNM stage(HR:0.444,95%CI:0.255-0.771),preoperative CEA level(HR:0.597,95%CI:0.386-8.790),and preoperative LMR level(HR:1.776,95%CI:1.150-2.741)were independent factors influencing the prognosis of signet ring gastric cancer.CONCLUSION In signet ring gastric cancer patients,a low preoperative LMR level predicts poor prognosis.The death risk ratio of the low LMR group compared to the high LMR group is 1.776. 展开更多
关键词 Gastric cancer Signet ring cell carcinoma Inflammation indexes Coagulation indexes PROGNOSIS
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Rising utilization of stable isotopes in tree rings for climate change and forest ecology 被引量:1
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作者 Ru Huang Chenxi Xu +3 位作者 Jussi Grießinger Xiaoyu Feng Haifeng Zhu Achim Bräuning 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第1期103-116,共14页
Analyses of stable isotopes(C,O,H)in tree rings are increasingly important cross-disciplinary programs.The rapid development in this field documented in an increasing number of publications requires a comprehensive re... Analyses of stable isotopes(C,O,H)in tree rings are increasingly important cross-disciplinary programs.The rapid development in this field documented in an increasing number of publications requires a comprehensive review.This study includes a bibliometric analysis-based review to better understand research trends in tree ring stable isotope research.Overall,1475 publications were selected from the Web of Science Core Collection for 1974-2023.The findings are that:(1)numbers of annual publications and citations increased since 1974.From 1974 to 1980,there were around two relevant publications per year.However,from 2020 to 2022,this rose sharply to 109 publications per year.Likewise,average article citations were less than four per year before 1990,but were around four per article per year after 2000;(2)the major subjects using tree ring stable isotopes include forestry,geosciences,and environmental sciences,contributing to 42.5%of the total during 1974-2023;(3)the top three most productive institutions are the Chinese Academy of Sciences(423),the Swiss Federal Institute for Forest,Snow and Landscape Research(227),and the University of Arizona(204).These achievements result from strong collaborations;(4)review papers,for example,(Dawson et al.,Annu Rev Ecol Syst 33:507-559,2002)and(McCarroll and Loader,Quat Sci Rev 23:771-801,2004),are among the most cited,with more than 1000 citations;(5)tree ring stable isotope studies mainly focus on climatology and ecology,with atmospheric CO_(2) one of the most popular topics.Since 2010,precipitation and drought have received increasing attention.Based on this analysis,the research stages,key findings,debated issues,limitations and direc-tions for future research are summarized.This study serves as an important attempt to understand the progress on the use of stable isotopes in tree rings,providing scientific guid-ance for young researchers in this field. 展开更多
关键词 Tree rings Stable isotopes Web of Science BIBLIOMETRIC
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Classic analogue of Autler–Townes-splitting transparency using a single magneto-optical ring resonator
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作者 吴利婷 曹文康 蒋昊林 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第10期420-427,共8页
We show that an optical transparency can be obtained by using only one single magneto-optical ring resonator. This effect is based on the splitting of counterclockwise and clockwise modes in the ring resonator. Within... We show that an optical transparency can be obtained by using only one single magneto-optical ring resonator. This effect is based on the splitting of counterclockwise and clockwise modes in the ring resonator. Within a proposed resonator-waveguide configuration the superposition between the two degeneracy broken modes produces a transparency window,which can be closed, open, and modified by tuning the applied magnetic field. This phenomenon is an analogue of Autler–Townes splitting, and the magnetic field is equivalent to the strong external pump field. We provide a theoretic analysis on the induced transparency, and numerically demonstrate the effect using full-wave simulation. Feasible implication of this effect and its potential applications are also discussed. 展开更多
关键词 magneto-optic effect dynamic tunable single optical ring resonator
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An Efficient Heterogeneous Ring Signcryption Scheme for Wireless Body Area Networks
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作者 Qingqing Ning Chunhua Jin +2 位作者 Zhiwei Chen Yongliang Xu Huaqi Lu 《Computer Systems Science & Engineering》 SCIE EI 2023年第11期2061-2078,共18页
Wireless body area networks(WBANs)are an emerging technology for the real-time monitoring of physiological signals.WBANs provide a mechanism for collecting,storing,and transmitting physiological data to healthcare pro... Wireless body area networks(WBANs)are an emerging technology for the real-time monitoring of physiological signals.WBANs provide a mechanism for collecting,storing,and transmitting physiological data to healthcare providers.However,the open wireless channel and limited resources of sensors bring security challenges.To ensure physiological data security,this paper provides an efficient Certificateless Public Key Infrastructure Heterogeneous Ring Signcryption(CP-HRSC)scheme,in which sensors are in a certificateless cryptosystem(CLC)environment,and the server is in a public key infrastructure(PKI)environment.CLC could solve the limitations of key escrow in identity-based cryptography(IBC)and certificate management for public keys in PKI.While PKI is suited for the server because it is widely used on the Internet.Furthermore,this paper designs a ring signcryption method that allows the controller to anonymously encrypt physiological data on behalf of a set of sensors,but the server does not exactly know who the sensor is.The construction of this paper can achieve anonymity,confidentiality,authentication,non-repudiation,and integrity in a logically single step.Under the computational Diffie-Hellman(CDH)problem,the formal security proof is provided in the random oracle model(ROM).This paper demonstrates that this scheme has indistinguishability against adaptive chosen ciphertext attacks(IND-CCA2)and existential unforgeability against adaptive chosen message attacks(EUF-CMA).In terms of computational cost and energy usage,a comprehensive performance analysis demonstrates that the proposed scheme is the most effective.Compared to the three existing schemes,the computational cost of this paper’s scheme is reduced by about 49.5%,4.1%,and 8.4%,and the energy usage of our scheme is reduced by about 49.4%,3.7%,and 14.2%,respectively. 展开更多
关键词 Wireless body area networks certificateless cryptosystem public key infrastructure SECURITY ring singncryption
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Study of Radio over Fiber Transmission with a Single Line in Ring Topology for Deployment of MIMO Antenna Access Points in a Cell-less Network
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作者 Mamadou Sarr Dialo Diop +1 位作者 Ndolane Diouf Kharouna Talla 《Journal of Sensor Technology》 2023年第2期13-23,共11页
The massive growth of wireless traffic goes hand in hand with the deployment of advanced radio interfaces as well as network densification. This growth has a direct impact on the radio access architecture, which today... The massive growth of wireless traffic goes hand in hand with the deployment of advanced radio interfaces as well as network densification. This growth has a direct impact on the radio access architecture, which today is moving from centralized to distributed deployments through the use of a large number of access points (APs). This paper verifies the feasibility of deploying multiple APs in series on a single line in a ring topology in a cell-less network. On the one hand, this technique will further improve the communication capacity and flexibility of a Radio-over-Fiber (RoF) based mobile communication system and will reduce its construction cost. And on the other hand, this deployment topology is a solution to achieve a massive cell-free Multiple-Input Multiple-Output (MIMO) architecture and a cost-effective fronthaul solution. First, a passive optical add/drop multiplexer (OADM) is used to extract and add downlink and uplink signals from the remote access points of one kilometer. Then, a deployment model is developed with version 17 Optisystem software. The results obtained showed that the quadrature amplitude modulation (QAM) does not adapt to this multi-carrier transmission to deploy several AP in series on a single line. Thus, the performance degradation increases when the number of APs integrated on the line increases. 展开更多
关键词 ROF ring Topology MIMO Antennas Cell-less network
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Dynamics of a rotating ring-stiffened sandwich conical shell with an auxetic honeycomb core
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作者 S.JAHANGIRI A.GHORBANPOUR ARANI Z.KHODDAMI MARAGHI 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第6期963-982,共20页
The free vibration analysis of a rotating sandwich conical shell with a reentrant auxetic honeycomb core and homogenous isotropic face layers reinforced with a ring support is studied.The shell is modeled utilizing th... The free vibration analysis of a rotating sandwich conical shell with a reentrant auxetic honeycomb core and homogenous isotropic face layers reinforced with a ring support is studied.The shell is modeled utilizing the first-order shear deformation theory(FSDT)incorporating the relative,centripetal,and Coriolis accelerations alongside the initial hoop tension created by the rotation.The governing equations,compatibility conditions,and boundary conditions are attained using Hamilton’s principle.Utilizing trigonometric functions,an analytical solution is derived in the circumferential direction,and a numerical one is presented in the meridional direction via the differential quadrature method(DQM).The effects of various factors on the critical rotational speeds and forward and backward frequencies of the shell are studied.The present work is the first theoretical work regarding the dynamic analysis of a rotating sandwich conical shell with an auxetic honeycomb core strengthened with a ring support. 展开更多
关键词 free vibration conical shell rotating shell ring support auxetic honeycomb
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Winter-spring minimum temperature variations inferred from tree-ring δ^(13)C in southeastern China
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作者 Wenli Li Feifei Zhou +1 位作者 Heng Zhang Keyan Fang 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第5期182-190,共9页
Long-term temperature variations inferred from high-resolution proxies provide an important context to evaluate the intensity of current warming.However,tem-perature reconstructions in humid southeastern China are sca... Long-term temperature variations inferred from high-resolution proxies provide an important context to evaluate the intensity of current warming.However,tem-perature reconstructions in humid southeastern China are scarce and particularly lack long-term data,limiting us to obtain a complete picture of regional temperature evolution.In this study,we present a well-verified reconstruction of winter-spring(January–April)minimum temperatures over southeastern China based on stable carbon isotopic(δ^(13)C)records of tree rings from Taxus wallichiana var.mairei from 1860 to 2014.This reconstruction accounted for 56.4%of the total observed variance.Cold periods occurred during the 1860s–1910s and 1960s–1970s.Although temperatures have had an upward trend since the 1920s,most of the cold extremes were in recent decades.The El Niño-Southern Oscillation(ENSO)variance acted as a key modulator of regional winter-spring minimum temperature variability.However,teleconnections between them were a nonlinear process,i.e.,a reduced or enhanced ENSO variance may result in a weakened or intensified temperature-ENSO relationship. 展开更多
关键词 Tree rings Carbon isotope Southeastern China Extreme coldness El nino-southern oscillation
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Climate warming is significantly influenced by rising summer maximum temperatures:insights from tree-ring evidence of the Western Tianshan Mountains,China
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作者 Meng Ren Yu Liu +3 位作者 Qiufang Cai Qiang Li Huiming Song Changfeng Sun 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第5期142-154,共13页
As one of the regions most affected by global climate warming,the Tianshan mountains has experienced several ecological crises,including retreating glaciers and water deficits.Climate warming in these mountains is con... As one of the regions most affected by global climate warming,the Tianshan mountains has experienced several ecological crises,including retreating glaciers and water deficits.Climate warming in these mountains is considered mainly to be caused by increases in minimum temperatures and winter temperatures,while the influence of maximum temperatures is unclear.In this study,a 300-year tree-ring chronology developed from the Western Tianshan Mountains was used to reconstruct the summer(June-August)maximum temperature(Tmax6-8) variations from 1718 to2017.The reconstruction explained 53.1% of the variance in the observed Tmax6-8.Over the past 300 years,the Tmax6-8reconstruction showed clear interannual and decadal variabilities.There was a significant warming trend(0.18 ℃/decade) after the 1950s,which was close to the increasing rates of the minimum and mean temperatures.The increase in maximum temperature was also present over the whole Tianshan mountains and its impact on climate warming has increased.The Tmax6-8variations in the Western Tianshan mountains were influenced by frequent volcanic eruptions combined with the influence of solar activity and the summer North Atlantic Oscillation.This study reveals that climate warming is significantly influenced by the increase in maximum temperatures and clarifies possible driving mechanisms of temperature variations in the Western Tianshan mountains which should aid climate predictions. 展开更多
关键词 Tree rings Western Tianshan mountains Temperature change Climate warming
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