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北欧岩高兰(Empetrum)生态系统:功能及其对环境变化的敏感性

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AMBIO－人类环境杂志 2000年第2期29卷 90-97页

作者： Knud Tybirk Marie-Charlotte Nilsson Anders Michelsen Hanne Lakkenborg Kristensen Anna shevtsova Morten Tune Strandberg Marianne Johansson Knud Erik Nielsen Torben Riis-Nielsen Beate Strandberg ib johansen 萨仁 NERI Dept.of Landscape Ecology Grenvej 14 DK-8410 Rnde Denraark Forest Vegetation Ecology SLU SE-90183 Ume Sweden Plant Ecology Φ.Farimagasgade 2DDK-1353 Copenhagen K Denmark of Forest Ecology Forest and Landscape Research Institute Hrsholm Kongevej 29 DK-2970 Hrshoim Denmark Biology University of Turku FIN-20014 Turku Finland Terrestrial Ecology NERI Vejlsvej 25 DK-8600 SilkeborgDenmark of Mycology Botanical Institute University of Copenhagen .Farimagasgade 2D DK-1353 Copenhagen K Denmark Forest Ecology Forest and Landscape Research Institute Hrsholm Kongevej 29 DK-2970 Hrsholm Denmark Plant Ecology University of Copenhagen .Farimagasgade 2D DK-1353 Copenhagen K Denmark

本文回顾了关于北欧地区岩高兰(Empetrum nigrum ***和***)生态系统的知识。因为岩高兰叶片及其枯枝落叶含有丰富的酚,分解缓慢,随着有机质表土层的形成,养分存储于有机养分库中,主要由具有石南状根的植物所吸收利用。黑果岩高兰(Empetr... 详细信息

本文回顾了关于北欧地区岩高兰(Empetrum nigrum ***和***)生态系统的知识。因为岩高兰叶片及其枯枝落叶含有丰富的酚,分解缓慢,随着有机质表土层的形成,养分存储于有机养分库中,主要由具有石南状根的植物所吸收利用。黑果岩高兰(Empetrum nigrum)亚种Hermaphroditum是强有力的养分竞争者,并且在演替后期能战胜多数植物。这是化学干扰(他感作用)和资源竞争所致。岩高兰作为一种有机体耐大气污染,在适林海岸石南丛生地,由于大气中大量氮的沉积其生长活力甚至有所增加,但是它对机械干扰及火烧非常敏感。然而,有迹象表明,空气中无机气氮的输入可对岩高兰占优势时所形成的封闭式营养循环产生干扰。

关键词：北欧岩高兰生态系统功能环境变化敏感性

Rethinking neurodegenerative diseases:neurometabolic concept linking lipid oxidation to diseases in the central nervous system

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Neural Regeneration Research 2024年第7期19卷 1437-1445页

作者： Steinunn Sara Helgudóttir Anne Skøttrup Mørkholt Jacek Lichota Preben Bruun-Nyzell Mads Christian Andersen Nanna Marie Juhl Kristensen Amanda Krøger johansen Mikela Reinholdt Zinn Hulda Maria Jensdóttir John Dirk Vestergaard Nieland 2N Pharma ApS NOVI Science ParkAalborgDenmark Molecular Pharmacology Group Department of Health Science and TechnologyAalborg UniversityAalborgDenmark

Currently,there is a lack of effective medicines capable of halting or reve rsing the progression of neurodegenerative disorde rs,including amyotrophic lateral sclerosis,Parkinson s disease,multiple sclerosis,or Alzheimer s *** the unmet medical need,it is necessary to reevaluate the existing para digms of how to to rget these *** considering neurodegenerative diseases from a systemic neurometabolic perspective,it becomes possible to explain the shared pathological *** innovative approach presented in this paper draws upon exte nsive research conducted by the authors and researchers *** this review,we highlight the importance of metabolic mitochondrial dysfunction in the context of neurodegenerative *** provide an overview of the risk factors associated with developing neurodegenerative disorders,including genetic,epigenetic,and environmental fa ***,we examine pathological mechanisms implicated in these diseases such as oxidative stress,accumulation of misfolded proteins,inflammation,demyelination,death of neurons,insulin resistance,dysbiosis,and neurotransmitter ***,we outline a proposal for the restoration of mitochondrial metabolism,a crucial aspect that may hold the key to facilitating curative therapeutic interventions for neurodegenerative disorders in forthcoming advancements.

关键词： brain disease carnitine palmitoyl transferase 1 epigenetics metabolism gut microbiome mitochondrial dysfunction neurodegeneration oxidative stress

Deals and Gifts: Exchange, Power, and Freedom in The Lady from the Sea

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外国文学研究 2005年第5期27卷 22-30页

作者： Joergen Dines johansen generaland comparative literature at the Cen-ter for Literature and Semiotics University of Southern Denmark Denmark

This article will explore the relationship between spouses in The Lady from the Sea from the point of view the difference between exchange and gift giving. In society, and in marriage, exchange plays a major role. Because of the division of labor goods are exchanged within society and between different societies. Within marriage, exchange of different kinds of use values also plays a major role, and ibsen is certainly aware of this: Marriage is a contract that explicitly or implicitly oblige the spouses to take care of and service each other in different ways. And this article attempts to prove that this is the core conflict in the pay.

关键词：易卜生国际学术研讨会挪威 2005年文学研究

Diapause development in early and late emerging phenotypes of Delia floralis

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Insect Science 2014年第1期21卷 103-113页

作者： Tor J. johansen Richard Meadow Arctic Agriculture and Land Use Division Bioforsk - Norwegian Institute for Agricultural and Environmental Research Tromsm plant Health and Plant Protection Division Bioforsk - Norwegian Institute for Agricultural and Environmental Research As Norway

The turnip fly, Delia floralis Fall6n （Diptera： Anthomyiidae） is an important insect pest of brassica vegetable crops in the holarctic region. Different populations have strongly varying temperature requirements for fly emergence, a challenge for accurate prediction of activity. This study focused on diapause development in one early and one late emerging phenotype. The physiological state after various treatments was deduced from emergence data. Our results showed a slow diapause progression at chilling conditions for both populations and diapause ended about 7 months after pupae were formed for the early population. For the late population held at 4℃ diapause did not end, no matter how long the duration of chilling. These pupae required a period with elevated temperatures above 6~C to continue development. At constant non-chilling conditions （18℃） from the time pupae were formed both populations completed diapause most rapidly. These results indicate that chilling delayed, rather than accelerated development and was not a prerequisite for diapause development. For post-diapause, results indicated a linear relationship between rate of development and temperature within the range of 6-18℃and a theoretical base temperature for development of about 2℃ for both populations. In conclusion, D. floralis pupae are in diapause throughout a long winter period, and delayed emergence of the late population appears to be caused by prolonged diapause regulated by a developmental temperature threshold. The study has added information on the biology of turnip fly populations, a prerequisite for improved pest control.

关键词： brassica chilling emergence hibernation quiescence

Quality incentive based congestion control for multimedia communication over IP networks

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第Z1期7卷 7-12页

作者： johansen Stian KIM Anna N. PERKIS Andrew Centre for Quantifiable Quality of Service in Communication Systems Norwegian University of Science and Technology Trondheim N-7034Norway

In this paper we introduce a framework for using quality as an incentive to promote proper application level congestion control. Through integrating a joint-source channel coder and feedback-based congestion control scheme, we are able to construct accurate and efficient quality incentives. The framework is applicable in all network architectures where end-to-end congestion control may be used, and is as such not specific to either best-effort or traffic class-based architectures. The concept is presented along with preliminary simulations that highlight the resulting rate control accuracy. We also discuss how to implement some well-known congestion control schemes within our framework.

关键词： Congestion control, Incentives, Video communication, Joint source/channel coding, Unequal error protection

Guaranteed feasible control allocation using model predictive control

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Control Theory and Technology 2019年第3期17卷 252-264页

作者： Mehdi NADERI Ali KHAKI SEDIGH Tor Arne johansen Center of Excellence in Industrial Control Faculty of Electrical Engineering K. N. Toosi University of Technology Seyyed Khandan Bridge Shariati Ave. Tehran Iran Center for Autonomous Marine Operation and Systems Department of Engineering Cybernetics Norwegian University of Science and Technology N7491 Trondheim Norway

This paper proposes a guaranteed feasible control allocation method based on the model predictive control. Feasible region is considered to guarantee the determination of the desired virtual control signal using the pseudo inverse methodology and is described as a set of constraints of an MPC problem. With linear models and the given constraints, feasible region defines a convex polyhedral in the virtual control space. In order to reduce the computational time, the polyhedral can be approximated by a few axis alig ned hypercubes. Employing the MPC with rectangular constraints substantially reduces the computational complexity .In two dimensions, the feasible region can be approximated by a few rectangles of the maximum area using numerical geometry techniques which are considered as the constraints of the MPC problem. Also, an active MPC is defined as the controller to minimize the cost function in the control horizon. Finally, several simulation examples are employed to illustrate the effectiveness of the proposed techniques.

关键词： Control allocation feasible region actuator constraints model predictive control

A Fault Tolerant Control Scheme Using the Feasible Constrained Control Allocation Strategy

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International Journal of Automation and computing 2019年第5期16卷 628-643页

作者： Mehdi Naderi Tor Arne johansen Ali Khaki Sedigh Center of Excellence in Industrial Control Faculty of Electrical EngineeringK.N.Toosi University of TechnologySeyyed Khandan BridgeShariati AvenueTehran ***Iran Center for Autonomous Marine Operation and Systems Department of Engineering CyberneticsNorwegian University of Science and TechnologyTrondheim 7491Norway

This paper investigates the necessity of feasibility considerations in a fault tolerant control system using the constrained control allocation methodology where both static and dynamic actuator constraints are considered. In the proposed feasible control allocation scheme, the constrained model predictive control(MPC) is employed as the main controller. This considers the admissible region of the control allocation problem as its constraints. Using the feasibility notion in the control allocation problem provides the main controller with information regarding the actuator′s status, which leads to closed loop system performance improvement. Several simulation examples under normal and faulty conditions are employed to illustrate the effectiveness of the proposed methodology. The main results clearly indicate that closed loop performance and stability characteristics can be significantly degraded by neglecting the actuator constraints in the main controller. Also, it is shown that the proposed strategy substantially enlarges the domain of attraction of the MPC combined with the control allocation as compared to the conventional MPC.

关键词： Control allocation feasibility fault tolerant control model predictive control domain of attraction

Estimating Hansen solubility parameters of organic pigments by group contribution methods

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Chinese Journal of Chemical Engineering 2021年第3期34卷 186-197页

作者： Markus Enekvist Xiaodong Liang Xiangping Zhang Kim Dam-johansen Georgios MKontogeorgis Center for Energy Resources Engineering(CERE) Department of Chemical and Biochemical EngineeringTechnical University of DenmarkBuilding 229Søltofts Plads 229DK-2800 Kgs.LyngbyDenmark Hempel Foundation Coatings Science and Technology Centre(CoaST) Department of Chemical and Biochemical EngineeringTechnical University of DenmarkBuilding 229Søltofts Plads 229DK-2800 Kgs.LyngbyDenmark Sino-Danish Center for Education and Research(SDC) IPEUniversity of Chinese Academy of SciencesBeijing 100049China Beijing Key Laboratory of Ionic Liquids Clean Process CAS Key Laboratory of Green Process and EngineeringState Key Laboratory of Multiphase Complex SystemsInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190China

The Hansen solubility parameters(HSP)are frequently used for solvent selection and characterization of polymers,and are directly related to the suspension behavior of pigments in solvent *** performance of currently available group contribution(GC)methods for HSP were evaluated and found to be insufficient for computer-aided product design(CAPD)of paints and coatings.A revised and,for this purpose,improved GC method is presented for estimating HSP of organic compounds,intended for organic *** to the significant limitations of GC methods,an uncertainty analysis and parameter confidence intervals are provided in order to better quantify the estimation accuracy of the proposed *** to other applicable GC methods,the prediction error is reduced significantly with average absolute errors of 0.45 MPa^(1/2),1.35 MPa^(1/2),and 1.09 MPa^(1/2) for the partial dispersion(δD),polar(δP)and hydrogen-bonding(δH)solubility parameters respectively for a database of 1106 *** performance for organic pigments is comparable to the overall method performance,with higher average errors forδD and lower average errors forδP andδH.

关键词： Hansen solubility parameters Group contribution method Organic pigments Computer-aided product design Parameter estimation Uncertainty analysis

Flow-Induced Acoustics in Corrugated Pipes

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Communications in Computational Physics 2011年第6期10卷 120-139页

作者： Mihaela Popescu Stein Tore johansen Wei Shyy Department of Process Technology Flow TechnologySINTEF Materials and Chemistry7046 TrondheimNorway Department of Aerospace Engineering University of MichiganAnn ArborMI 48109USA

When gas flows through corrugated pipes,pressure waves interacting with vortex shedding can produce distinct tonal noise and structural *** on established observations,a model is proposed which couples an acoustic pipe and selfexcited oscillations with vortex shedding over the corrugation *** the model,the acoustic response of the corrugated pipe is simulated by connecting the lossless medium moving with a constant velocity with a source based on a discrete distribution of van der Pol oscillators arranged along the *** time accurate solutions exhibit dynamic behavior consistent with that experimentally observed,including the lock-in frequency of vortex shedding,standing waves and the onset fluid velocity capable of generating the lock-in.

关键词： Computational fluid dynamics aeroacoustics sound generation riser corrugated pipes wave propagation low Mach number gas flow flow-induced vibrations