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Robust Adaptive Model Tracking for Distributed Parameter Control of Linear Infinite-dimensional Systems in Hilbert Space

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IEEE/CAA Journal of Automatica Sinica 2014年第3期1卷 294-301页

作者： Mark J.Balas Susan a.frost the Embry-Riddle Aeronautical University the NASA Ames Research Center

This paper is focused on adaptively controlling a linear infinite-dimensional system to track a finite-dimensional reference *** a linear continuous-time infinite-dimensional plant on a Hilbert space with disturbances of known waveform but unknown amplitude and phase,we show that there exists a stabilizing direct model reference adaptive control law with the properties of certain disturbance rejection and *** plant is described by a closed,densely defined linear operator that generates a continuous semigroup of bounded operators on the Hilbert space of *** central result will show that all errors will converge to a prescribed neighborhood of zero in an infinitedimensional Hilbert *** result will not require the use of the standard Barbalat’s lemma which requires certain signals to be uniformly *** result is used to determine conditions under which a linear infinite-dimensional system can be directly adaptively controlled to follow a reference *** particular,we examine conditions for a set of ideal trajectories to exist for the tracking *** results are applied to adaptive control of general linear diffusion systems described by self-adjoint operators with compact resolvent.

关键词： Adaptation models Adaptive control Hilbert space Learning (artificial intelligence) Robustness Trajectory adaptive control algorithm adaptive theory distributed parameter system Distributed parameter systems Hilbert space trajectory Adaptation models reference model adaptive control Robustness Computer algorithms

The Ways and Wonders of South African Trees

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ChinAfrica 2025年第1期17卷 64-64页

作者： WILLEM frost 不详

Struik Nature The book celebrates the remarkable diversity and beauty of indigenous trees,o"ering an engaging exploration of their fascinating *** into two sections,the book delves into both the intricate biology of t... 详细信息

关键词： beauty African photograph

Raman and FTIR spectroscopy of natural oxalates: Implications for the evidence of life on Mars

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Chinese Science Bulletin 2003年第17期48卷 1844-1852页

作者： R.L.frost YANGJing ZheDing InorganicMaterialsResearchProgram QueenslandUniversityofTechnology2GeorgeStreetBrisbaneGPOBox2434Queensland4001Australia SchoolofMaterials ChinaUniversityofGeosciencesBeijing100083China

Evidence for the existence of primitive life forms such as lichens and fungi can be based upon the for-mation of oxalates. Oxalates are most readily detected using Raman spectroscopy. A comparative study of a suite of natural oxalates including weddellite, whewellite, moolooite, humboldtine, glushinskite, natroxalate and oxammite has been undertaken using Raman spectroscopy. The minerals are characterised by the Raman position of the CO stretch-ing vibration which is cation sensitive. The band is observed at 1468 cm-1 for weddellite, 1489 cm-1 for moolooite, 1471 cm-1 for glushinskite and 1456 cm-1 for natroxalate. Except for oxammite, the infrared and Raman spectra are mutually exclusive indicating the minerals are bidentate. Differences are also observed in the water OH stretching bands of the minerals. The significance of this work rests with the ability of Raman spectroscopy to identify oxalates which often occur as a film on a host rock. As such Raman spectroscopy has the potential to identify the existence or pre-existence of life forms on planets such as Mars.

关键词：火星地外生命草酸盐草酸铵石草酸镁石拉曼光谱学傅里叶变换红外光谱学

Gut microbial pathways for bile acid metabolism

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Hepatobiliary Surgery and Nutrition 2021年第3期10卷 379-381页

作者： Fabian frost Markus M.Lerch Department of Medicine A University Medicine GreifswaldGreifswaldGermany

The human gut represents a complex ecosystem which harbours a diverse,predominantly anaerobic bacterial *** microbiota are not just passive bystanders but active contributors to human metabolism interfering with numer... 详细信息

关键词： metabolism bile pathways

A new CGMW map released：The International Metallogenic Map of Africa at a scale of 1：5000000

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Episodes 2003年第2期26卷 116-118页

作者： frost-Killian, Susan Hammerbeck, Erik C.I. Council of Geoscience Pretoria 0001 Private Bag X112 South Africa

The International Metallogenic Map of Africa, at a scale of 1:5 000 000 was prepared by the Council for Geoscience, South Africa, under the auspices of the Commission for the Geological Map of the World (CGMW) with support from UNESCO. The map was published by the CGMW and the Council for Geoscience in 2002. The map supersedes an earlier version of the International Mineral Deposit Map of Africa (Sheet 1), produced in 1991. It was predominantly compiled by a team of 5 members, led by Dr. Erik Hammerbeck, Milica Veselinovic-Williams and Susan frost-Killian. Several co-authors and co-operators, including various research institutions and most of the African and Middle Eastern Geological Surveys, as well as the Bureau de Recherches Géologiques et Minières (BRGM, French Geological Survey), assisted with the compilation and verification of the mineral deposit and background geological data.

关键词： CGMW地图非洲 1:5000000比例地图金属成矿地图矿床分布

Syringoceles of Cowper’s ducts and glands in adult men

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Asian Journal of Andrology 2020年第2期22卷 129-133页

作者： Simon Bugeja Anastasia.frost Stella Ivaz Mariya Dragova Daniela E Andrich Anthony R Mundy Reconstructive Urology Unit University College London Hospitals NHS Foundation TrustLondon NW12PGUK

Cowper’s syringoceles are uncommon,usually described in children and most commonly limited to the *** describe more complex variants in an adult population affecting with varying degrees of severity,the glands themselves,and the complications they may lead *** hundred consecutive urethrograms of patients with unreconstructed strictures were ***-six patients(mean age:41.1 years)with Cowper’s syringoceles who were managed between 2009 and 2016 were subsequently ***,radiological appearance,treatment(when indicated),and outcomes were *** 100 urethrograms in patients with strictures,33.0%demonstrated filling of Cowper’s ducts or glands,occurring predominantly in patients with bulbar *** 1 of 26 patients with non-bulbar strictures had a visible duct/*** 26 symptomatic patients,15 presented with poor *** four patients,a grossly dilated Cowper’s duct obstructed the *** the remaining 11 patients,a bulbar stricture caused the symptoms and the syringocele was identified *** patients presented with perineal *** six of them,fluoroscopy and magnetic resonance imaging(MRI)revealed complex multicystic lesions within the bulbourethral *** patients developed perineoscrotal *** the 11 patients with strictures,the syringocele was no longer visible after *** three of four patients with urethral obstruction secondary to a dilated Cowper’s duct,this resolved after transperineal excision(n=2)and endoscopic deroofing(n=1).Five of six patients with complex syringoceles involving Cowper’s glands were excised surgically with symptomatic relief in *** conclusion,Cowper’s syringocele in adults is more common than previously thought and may cause lower urinary tract symptoms or be associated with serious complications which usually require surgical treatment.

关键词： complications Cowper’s glands syringocele treatment urethral stricture

Funneling of the bladder neck - radiological appearance after radical retropubic prostatectomy and clinical relevance

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Asian Journal of Andrology 2020年第2期22卷 152-153页

作者： Simon Bugeja Anastasia.frost Stella Ivaz Felix Campos Daniela E Andrich Anthony R Mundy University College London Hospitals NHS Foundation TrustReconstructive Urology UnitLondon NW12PGUK

Several authors have commented on the anatomical changes following radical prostatectomy(RP)for prostate cancer and their characteristic radiological appearances.1,2 Most of these relate to periurethral fibrosis and its clinical significance in patients with postprostatectomy sphincter weakness incontinence.3,4 On magnetic resonance imaging(MRI),this postsurgical fibrosis appears as a focus of low-signal intensity in the periurethral tissues at and around the level of the vesicourethral anastomosis(VUA)which is appreciable on both T1-and T2-weighted images.

关键词： bladder clinical radiological

Distribution and quantitative zonation of unloading cracks at a proposed large hydropower station dam Site

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Journal of Mountain Science 2017年第10期14卷 2106-2121页

作者： ZHAO Wei-hua.frost J.D. HUANG Run-qiu YAN Ming JIN Long-de State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of TechnologyChengdu School of Civil and Environmental Engineering Georgia Institute of Technology

Rock mass unloading is an important rock engineering problem because unloading may impact the stability of a rock mass slope. Based on hydroelectric engineering principles, this study focuses on the classification of unloading zones to reflect the rock mass structure characteristics. Geological background and slope structure of the study region were considered to investigate the distribution and deformation of the unloading process. Quantitative indices were classified according to the formation mechanisms and the geological exhibition of unloading zones. The P-wave velocity(V_P), the ratio of the wave velocity(V_p) the ratio of the test P-wave velocity along the adit depth to the P-wave velocity of intact rock, the sum of joint openings every 2 meters(S_t), and the density of open joints(D_t) were calculated as quantitative indices for the rock mass unloading zone. The characteristics of the unloading zone of rock mass slopes at the dam site were successfully determined. The method of combining qualitative data with quantitative indices was found to be effective for the classification of slope unloading zones.

关键词： Slope Structure Unloading Phenomena Classify Unloading Zones Quantitative Indexes

Cyclic load testing of pre-stressed rock anchors for slope stabilization

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Journal of Mountain Science 2016年第1期13卷 126-136页

作者： ZHENG Da LIU Fang-zhou JU Neng-pan frost J.David HUANG Run-qiu State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of Technology School of Civil and Environmental Engineering Georgia Institute of Technology

The objective of this research was to assess the characteristics of seismic induced damage and the deformation patterns of pre-stressed cement-grouted cables that are used for rock slope stabilization projects subjected to quasi-static cyclic *** experimental configuration includes the installation of 15 pre-stressed cables in a slope model made of concrete blocks(theoretically rigid rock mass) on top of a pre-existing sliding *** study showed that:(i) The pre-stressed cables exhibited great seismic *** displacement of the model blocks was observed after the complete loss of the initial pre-stress load under continued applied cyclic loads and exceedance of the state of equilibrium,which implies the higher the initial pre-stress load,the better the seismic performance of the rock anchor;(ii) The failure of the pre-stressed cables was due to fracture at the connection of the tendons and cable heads under cyclic *** sequence of failure had a distinct *** was first observed at the upper row of cables,which experienced the most severe damage,including the ejection of cable *** evidence of de-bonding was observed during the cyclic loading;(iii) The stress distribution of the bond length for pre-stressed cables was highly *** stress concentrations were observed at both the fixed end and the free end of the bond length both before and immediately after the state of equilibrium is *** results obtained can be used to evaluate the overall performance of pre-stressed rock anchors subject to seismic loading and their potential as rockfall prevention and stabilization measures.

关键词： stabilization rock sliding stressed cable blocks anchor ejection implies experienced