检索结果-南通市图书馆

Lasalle-Razumikhin Theorem and Adaptive Control of Nonlinear Systems with Time-Delay

在线全文

cnki会议

学校读者我要写书评

暂无评论

Lasalle-Razumikhin Theorem and Adaptive Control of Nonlinear...

第二十二届中国控制会议

作者： katsutoshi tamura Department of Mechanical Engineering Sophia University Kioicho 7-1Chiyoda-kuTokyo102-8554Japan

＜正＞This paper provides a new method to design adaptive controller for nonlinear systems with uncertain time-delay. The method is established on a novel sufficient condition which ensures the stability with convergence of partial states of nonlinear time-delay system. The condition is derived by using LaSalle-Razumikhin Theorem based on Lyapunov-Razumikhm function. With the help of this new condition, it is able to extend the adaptive control approaches of nonlinear systems to time-delay systems, including such as the backstepping approach, Lyapunov recursive approach and passivity-based design method that are the most successful methodology obtained in the research .field of nonlinear control in the last decade. In this paper, we show a design approach to an adaptive controller for a class of nonlinear time-delay system with triangular structure.

关键词： Time-delay nonlinear systems adaptive Lyapunov-Razumikhin function

State Feedback Stabilization of Cascaded Nonlinear Systems with Discontinuous Connection

在线全文

cnki会议

学校读者我要写书评

暂无评论

State Feedback Stabilization of Cascaded Nonlinear Systems w...

第25届中国控制会议

作者： Hirano Maiko tamura katsutoshi Department of Mechanical Engineering Sophia University7-1KioichoChiyoda-kuTokyo102-8554 JAPAN Department of Mechanical Engineering Sophia University7-1KioichoChiyoda-kuTokyo102-8554 JAPAN

＜正＞In the practical engineering, many natures is described as a discontinuous function of state variable, and the discontinuity is usually main reason that damage the control performance. For example,in the set-point control problem of mechanical system, the static friction which is described by a sgn function of velocity of the contacting faces causes undesired positioning error. In this paper, we will investigate the stabilization problem for a class of nonlinear systems that consist of two subsystems with cascaded connection. We will show the basic idea with a special case first,and then the result will be extended to more general cases. Some interesting numerical examples will be given to demonstrate the effectiveness of the proposed design approach.

关键词： Cascaded Connection Discontinuous Systems Filippov’s Solution

Robust stabilization for nonlinear systems with uncertain delay and input dynamics

在线全文

cnki会议

学校读者我要写书评

暂无评论

Robust stabilization for nonlinear systems with uncertain de...

第二十一届中国控制会议

作者： SHEN Tie-longnm katsutoshi tamura Department of Mechanical Engineering Sophia University Kioicho 7-1Chiyoda-kuTokyo102-8554Japan Department of Mechanical Engineering Sophia University Kioicho 7-1Chiyoda-kuTokyo102-8554Japan

＜正＞This paper address the robust stabilization problem for a class of nonlinear systems with uncertain time-delay and input dynamics. A robust stability condition for the uncertain systems is given based on the Razumikhin theorem. Using the sufficient condition, a design approach to robust stabilizing controller is proposed for a scalar system with the uncertainty, and then it will be shown that using the proposed design approach, a recursive constructing principle can be employed to design the robust stabilizing controller for the high order systems.

关键词： nonlinear systems uncertain input dynamics uncertain time-delay robust stabilization Razumikhin condition

ROBUST CONTROL OF NONLINEAR SYSTEMS WITH DISTURBANCE ATTENUATION

在线全文

cnki会议

学校读者我要写书评

暂无评论

ROBUST CONTROL OF NONLINEAR SYSTEMS WITH DISTURBANCE ATTENUA...

第二十届中国控制会议

作者： Kazuhisa Itou Yasuhiko Mutoh katsutoshi tamura Sophia University Kioicho 7-1Chiyoda-kuTokyo 102-8554Japan Sophia University Kioicho 7-1Chiyoda-kuTokyo 102-8554Japan Sophia University Kioicho 7-1Chiyoda-kuTokyo 102-8554Japan

＜正＞For SISO uncertain nonlinear system, we show how the problem of global robust stabilization via recursive design can be solved by using less conservative bounding functions. The system is assumed to have gain bounded unknown nonlinear functions with a semi-strict feedback structure. Moreover, by modifying a Lyapunov-like function, we extend the obtained controller to have a disturbance attenuation property.

关键词： nonlinear systems robust stabilization robust L2 gain disturbance attenuation Lyapunov-based recursive design

Increasing spatial coverage in rough terrain and vegetated areas using InSAR optimized pixel selection:application to Tohoku,Japan

在线全文

cnki会议

学校读者我要写书评

暂无评论

Geo-Spatial Information Science 2022年第2期25卷 295-311页

作者： Tamer ElGharbawi Masayuki tamura Civil and Earth Resources Engineering Department Kyoto UniversityKyotoJapan

One of the major limitations of using Interferometric Synthetic Aperture Radar(InSAR)in time series analysis is the low-phase coherence associated with rough terrain and vegetated areas,which results in limited spatial coverage in such *** scatterers technique was introduced to overcome this limitation using time-series ***,identifying major scatterers within a pixel requires the single-looked pixels oversampling which can be a demanding process especially with large interferometric stacks and vast study ***,using multilooked temporal coherent pixels was proposed to increase processing efficiency and coverage by utilizing distributed targets,but this technique may exclude pixels with reliable phase returns because of their temporal varying neighboring *** this paper,we propose a technique to identify multilooked temporal stable pixels with reliable phase returns independent of their neighboring *** conduct a simulation analysis to relate the spatial coherence of a pixel with its expected temporal correlation in the time series analysis *** found that a liberal temporal correlation threshold of 0.53 in multilooked pixels stack is equivalent to a spatial coherence threshold of 0.2 when using number of looks of 9,which is considered acceptable in temporal coherent pixels,in terms of phase standard *** these findings to study the 2011 Tohoku earthquake in the northeastern part of Japan resulted in increasing the number of usable pixels and spatial coverage index by nearly 50.4%and 36.8%,respectively,compared to the temporal coherent ***,we propose an approach to integrate GPS observations with InSAR time series analysis,which resulted in deformation maps of the megathrust 2011 Tohoku earthquake with mean RMSE of 11.4 mm and a correlation of 98%in comparison to GPS observations.

关键词： 2011 Tohoku earthquake temporal stable pixels coherence phase noise GPS coverage index

Alterations of tumor suppressor and tumor-related genes in the development and progression of gastric cancer

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

World Journal of Gastroenterology 2006年第2期12卷 192-198页

作者： Gen tamura Department of Pathology Yamagata University School of MedicineYamagata 990-9585Japan

The development and progression of gastric cancer involves a number of genetic and epigenetic alterations of tumor suppressor and tumor-related genes. The majority of differentiated carcinomas arise from intestinal metaplastic mucosa and exhibit structurally altered tumor suppressor genes, typified by p53, which is inactivated via the classic two-hit mechanism, i.e. loss of heterozygosity （LOH） and mutation of the remaining allele. LOH at certain chromosomal loci accumulates during tumor progression. Approximately 20% of differentiated carcinomas show evidence of mutator pathway tumorigenesis due to hMLH1 inactivation via hypermethylation of promoter CpG islands, and exhibit high-frequency microsatellite instability. In contrast, undifferentiated carcinomas rarely exhibit structurally altered tumor suppressor genes. For instance, while methylation of E-cadherin is often observed in undifferentiated carcinomas, mutation of this gene is generally associated with the progression from differentiated to undifferentiated carcinomas. Hypermethylation of tumor suppressor and tumor-related genes, including APC, CHFR, DAP- kinase, DCC, E-cadherin, GSTP1, hMLH1, p16, PTEN, RASSF1A, RUNX3, and TSLC1, can be detected in both differentiated and undifferentiated carcinomas at varying frequencies. However, the significance of the hypermethylation varies according to the analyzed genomic region, and hypermethylation of these genes can also be present in non-neoplastic gastric epithelia. Promoter demethylation of specific genes, such as MAGE and synudein y, can occur during the progressive stages of both histological types, and is associated with patient prognosis. Thus, while the molecular pathways of gastric carcinogenesis are dependent on histological background, specific genetic alterations can still be used for risk assessment, diagnosis, and prognosis.

关键词： Gastric cancer p53 E-cadherin hMLH1 Methylation

Pediatric kidney transplantation during the COVID-19 pandemic

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

World Journal of Clinical Cases 2022年第34期10卷 12494-12499页

作者： Hiroshi tamura Department of Pediatrics Kumamoto UniversityKumamoto 860-8556Japan

A waiting list for non-emergency transplant medical care was recommended in the first half of 2020 due to the coronavirus disease 2019(COVID-19)***,the number of kidney transplants temporarily ***,the waiting list for transplant medical care was lifted in the latter half of 2020 with the establishment of a polymerase chain reaction test system and the spread of infection *** basic stance is to recommend vaccination to posttransplant recipients,recipients,and donors who are scheduled to undergo transplantation,and their families,with the start of vaccine therapy in *** mortality rate of patients undergoing kidney transplants who had COVID-19 is slightly higher than healthy persons,and acute kidney injury was reported to lead to graft ***,pediatric cases of severe disease are rare and without *** transplantation medical care will be continuously provided by implementing infection prevention and treatments based on the latest evidence,promoting donated kidney transplantation,and hoping that pediatric patients with renal failure will grow up healthy,both physically and mentally,and become independent members of society,just like healthy children.

关键词： Kidney transplantation COVID-19 pandemic Children

Response of understory vegetation over 10 years after thinning in an old-growth cedar and cypress plantation overgrazed by sika deer in eastern Japan

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

Forest Ecosystems 2017年第2期4卷 93-102页

作者： Atsushi tamura Masanobu Yamane Division of Forest Research and Nature Restoration Planning Kanagawa Prefecture Natural Environment Conservation Center 657 Nanasawa AtsugiKanagawa 243-072 Japan

Background： Forest management strategies such as thinning have long been used to enhance ecosystem functions, especially in *** in plantations with high deer density, however, may not yield a desired increase in understory vegetation because deer graze on germinating plants after ***, we examine the changes in understory vegetation after thinning in plantations that have been overgrazed by sika deer to provide insight into the effects of thinning on ecosystem functions such as soil conservation and biological ***： We conducted our survey in the Tanzawa Mountains of eastern *** surveyed the change in understory vegetation within and outside of three deer exclosures on a single slope with three levels of understory vegetation cover： sparse（1%, exclosure ＂US＂）, moderate（30%, exclosure ＂MM＂）, and dense（80%, exclosure ＂LD＂） over10 years after a 30% thinning of an old-growth cedar and cypress plantation which was overgrazed by sika ***： Understory vegetation cover, biomass and species richness increased within and outside the ＂US＂ and＂MM＂ exclosures after thinning, and biomass was greater within than outside the exclosures at 10 years after *** species dominated both ＂US＂ and ＂MM＂ exclosures before thinning, and trees and shrubs dominated within the exclosures over time after *** contrast, unpalatable, grazing-tolerant, perennial,and annual species increased outside the ＂US＂ and ＂MM＂ *** noticeable changes were observed within and outside the ＂LD＂ exclosure when compared with the ＂US＂ and ＂MM＂ ***： Our results suggest that thinning a stand by 30% based on volume resulted in an increase in understory vegetation cover mainly composed of both unpalatable and grazing-tolerant species in a plantation forest where understory vegetation is sparse or moderate and sika deer density is *** emphasize that establishing deer exclosures or controlling deer is essential to ma

关键词： Biomass Deer exclosure Grazing-tolerant species Understory cover Unpalatable species

Dynamic robust optimal reorder point with uncertain lead time and changeable demand distribution

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2010年第12期11卷 938-945页

作者： Masaki tamura Kazuko MORIZAWA Hiroyuki NAGASAWA Department of Electrical and Information Systems Engineering Graduate School of EngineeringOsaka Prefecture University Osaka Prefectural College of Technology

In fixed order quantity systems,uncertainty in lead time is expressed as a set of scenarios with occurrence probabilities,and the mean and variance in demand distribution are supposed to be changeable according to a known pattern.A new concept of "dynamic robust optimal reorder point" is proposed in this paper and its value is calculated as a "robust optimal reorder point function with respect to reorder time".Two approaches were employed in determining the dynamic optimal reorder *** first is a shortage rate satisfaction approach and the second is a backorder cost minimization *** former aims at finding the minimum value of reorder point at each reorder time which satisfies the condition that the cumulative distribution function (CDF) of shortage rate under a given set of scenarios in lead time is greater than or equal to a basic CDF of shortage rate predetermined by a *** the latter approach,the CDF of closeness of reorder point is defined at each reorder time to express how close to the optimal reorder points under the set of scenarios,and the dynamic optimal reorder point is defined according to stochastic *** numerical examples demonstrate the features of these dynamic robust optimal reorder points.

关键词： Reorder point Lead time Robust optimum Uncertainty Scenario