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With increasing the penetration rate of microgrids in power networks, their control becomes more and more important, and microgrid frequency control in islanded mode is one of the most important recent approaches which are studied. With the aim of fast microgrid frequency adjustment, this study presents a novel robust approach using fuzzy and reset techniques. Therefore, this paper firstly describes the model of an islanded microgrid consisting of various elements such as renewable resources, variable loads, storage resources and distributed energy resources, and then designs and presents a robust hybrid control technique based on switching. The planned control method consists of three parts, which are: 1-Fuzzy control technique, 2- Fuzzy reset control technique, and 3- Switching between the two techniques. Due to the robust feature of the reset technique, which in addition to quickly reducing the frequency error, it is able to overcome the limitations of linear controllers, and also due to the intelligence of the innovative fuzzy technique, the planned technique is able to quickly remove frequency errors and restore the islanded microgrid frequency in the fastest possible time and with the least ups and downs and fluctuations. As the results of simulation and comparison in MATLAB environment show, the planned technique has a high and undeniable ability to overcome the uncertainty of the model and disturbances on the system even of the most severe type. [ABSTRACT FROM AUTHOR]

In this paper, a direct current (DC) motor speed control system with proportional-integral-derivative (PID) controller and Kalman filter is presented with consideration of disturbance, system variation, and feedback sensor noise and verified through computer simulations. Initially, a mathematical model for a DC motor system is introduced, after which the performance degradation due to disturbance and system variation in the basic open-loop control is revealed. To resolve this problem, a PID controller based feedback system is designed for the DC motor speed control system. Third, to improve the performance degradation due to feedback sensor noise that may occur during the feedback process, the Kalman filter is applied for the DC motor speed control system. Ultimately, it is verified that the designed DC motor speed control system with PID controller and Kalman filter not only satisfies all performance criteria but also has the ability to reject disturbance, cope with system variation and reduce feedback sensor noise. [ABSTRACT FROM AUTHOR]

Cascade control is widely used in the process industry, especially to reject disturbances. Typically, the controller parameters in the inner and outer loops of the cascade controller structure are defined in a strict sequence. In this paper, simultaneous tuning of cascade controllers is proposed to improve the performance of the system under load disturbance. For this purpose, the cost function of a nonlinear optimization problem is formulated to minimize the effect of disturbances on the system output. In addition, robustness constraints are defined for the maximum sensitivity function to independently guarantee a robust system for inner and outer loops. In this sense, the designer can explicitly and independently address the trade-off between performance and robustness for both loops. Simulation studies illustrate the performance and effectiveness of the proposed controller design method compared to well-known methods in the literature. These results indicate that the proposed method reduces the integrated absolute error (IAE) under load disturbance by up to 58 %. In addition, experimental results from a tank-level control application in the mineral process industry illustrate the practical applicability of the proposed method. In this case, the proposed method reduces the IAE under load disturbance by 37 %. [ABSTRACT FROM AUTHOR]

A new coring bit with a barrier ring was developed to address the disturbance problem associated with the common method of lunar soil sampling. This new coring bit is presented in this paper along with an analysis of the physical characteristics of regolith and coring bits. The structural parameters of the barrier ring, which disturbs the original state of the soil, are also analyzed. A user-defined material, based on the user-defined material mechanical behavior (UMAT) subroutine in the ABAQUS finite-element software, was used to simulate the contact area between the lunar soil and the barrier. The simulation results showed that the structure of the barrier ring has a significant effect on the stress and displacement produced in the lunar soil below the coring bit, but has little effect on the soil inside the ring. The test results showed that the coring bit with the barrier ring achieves a higher coring rate and causes less disturbance than a common bit. [ABSTRACT FROM AUTHOR]

In this paper, a new observer-based controller for a class of polynomial fuzzy systems with disturbance is proposed. First, by some appropriate equivalence transformation of the polynomial fuzzy model, the first output-sized states can be obtained directly from the output, which eventually enables us to obtain the feedback control gain and observer-related parameters together without considering the so-called separation principle. Second, with the disturbance in mind, a PI-type observer is suggested. Finally, the sum of squares for the stability of the closed-loop observer-based control system is provided. © 2015 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. [ABSTRACT FROM AUTHOR]

This paper summarizes those substantial theoretical concepts or methods for applications within interdisciplinary or practical uses published by Czech autors (geobotanists = ecological botanists, plant ecologists and ecophysiologists) during the second half of the 20th century, that were internationally cited. All selected thematical clusters are of landscape-ecological relevance through various contexts. Examples include the concepts of (potential) reconstructed vegetation in maps (R. Neuhäusl, Z. Neuhäuslová), linear vegetation features (corridors in landscape) and deductive classification of vegetation (K. Kopecký), analysis of soil seed bank (Z. Kropáč), dependency of macrophyte plant stands on ecodynamics (S. Hejný), dynamic periodicity in segetal vegetation (Z. Kropáč, E. Hadač, S. Hejný), anemo-orographic system explaining species richness in mountain regions (J. Jeník), productivity in grassland ecosystems (M. Rychnovská, J. Květ), elementary landscape units based on homogenity and potential vegetation (E. Hadač), landscape dispensation phenomena (V. Ložek), afforestation of coastal sandy dunes - the Netherlands, and polluted areas - the Czech Republic (J. Fanta), invasive plants and invasions into landscapes (M. Rejmánek). [ABSTRACT FROM AUTHOR]

This paper proposes a neural network-based robust model predictive control (MPC) strategy for visual serving of autonomous vehicles (AVs) with uncertain payloads, ground friction disturbances, and air resistance effects. Based on the dynamics of visual servoing errors and driving of the AV, the quasi-min–max MPC is adopted to calculate the desired velocity of the AV subject to the constraints on the speed, control, and the visual field. The backpropagation (BP) neural network is then used to learn the ground friction disturbances of the AV, which is adopted to compensate the quasi-min–max MPC of the visual servoing system. Finally, the performance of the proposed controller is evaluated and verified by some comparison simulations. [ABSTRACT FROM AUTHOR]

Temperate woodland vegetation is initially determined by spatiotemporal and historical factors, mediated by complex biotic interactions. However, catastrophic events such as disease outbreaks (e.g., sweet chestnut blight, ash dieback), infestations of insect pests, and human-accelerated climate change can create canopy gaps due to systematic decline in, or loss of, tree species that was once an important part of the canopy. Resultant cascade effects have the potential to alter the composition of woodland ecosystems quickly and radically, but inherent lag times make primary research into these effects challenging. Here, we explore change in woodland vegetation at 10 sites in response to canopy opening using the Elm Decline, a rapid loss of Ulmus in woodlands across northwestern Europe ~ 5800 years ago that coexisted alongside other stressors such as increasing human activity, as a palaeoecological analogue. For arboreal taxa, community evenness significantly decreased, within-site turnover significantly increased, and richness remained unchanged. Changes in arboreal taxa were highly site-specific but there was a substantial decline in woody climbing taxa, especially Hedera (ivy), across the majority of sites. For shrub taxa, richness significantly increased but evenness and turnover remained consistent. Interestingly, however, there was a significant increase in abundance of shrubs at 70% of sites, including Calluna (heather), Ilex (holly) and Corylus (hazel), suggesting structural change. Surprisingly, there was no change in richness, evenness or turnover for herb taxa, possibly because change was highly variable spatially. However, there was a marked uptick in the disturbance indicator Plantago (plantain). Overall, these findings suggest that woodlands with sustained reduction in, or loss of, a tree species that once formed an important part of the canopy has profound, but often spatially idiosyncratic, impacts on vegetation diversity (richness), composition (evenness), stability (turnover), and on abundance of specific taxa, especially within the shrub layer. Use of this palaeoecological analogue, which was itself complicated by cooccurring changes in human activity, provides a valuable empirical insight into possible cascade effects of similar change in canopy opening in contemporary settings, including Ash Dieback. [ABSTRACT FROM AUTHOR]

The occurrence of droughts in recent decades has prompted researchers to pay closer attention to soil shrinkage. It is no longer appropriate to assume that surface soils in temperate countries are always saturated. When using traditional geotechnical identifications for soil classification based on swelling and shrinkage, the soil density is not consistently considered as a crucial parameter, nor is the state of the soil (intact or disturbed) or the degree of soil cementation. This article highlights the importance of studying the soil in its intact state to accurately represent its behavior on-site. The microstructure of undisturbed soil differs from that of disturbed soil and governs its macroscopic behavior. The method and level of soil disturbance have an impact on the results, depending on whether the focus is on shrinkage or swelling behavior and cementation. This research demonstrates that disturbed samples of clayey soils (Romainville green clay) exhibit lower shrinkage amplitude than intact clayey soil samples, whereas disturbed marly soil samples (Argenteuil blue marl) show the opposite trend. Furthermore, depending on the disturbance method, the swelling amplitude of intact soil samples may be higher or lower than that of disturbed soil samples. The results indicate that conducting a swelling test on W-disturbed samples and a shrinkage test on C-disturbed samples allows us to assess more closely the behavior of intact soil samples. In conclusion, recommendations for a more accurate assessment of the swelling-shrinkage potential of any given soil are provided, considering the test method and the level of disturbance of the sample. [ABSTRACT FROM AUTHOR]

We aimed to analyze the natural population characteristics and habitat growth conditions of the valuable seaweed Silvetia siliquosa. Its population characteristics and habitat conditions were assessed monthly from May 2022 to April 2023 and April to August 2022, respectively, on selected habitats. The average population density, coverage, and frequency of S. siliquosa were 579 ± 94.18 ind./m2, 27.82 ± 6.92%/m2, and 78.37 ± 5.98/m2, respectively. The average thallus length and width were 47.53 ± 4.35 and 46.33 ± 4.17 mm, respectively, while the branch width, thickness, and frequency were 2.35 ± 0.03 mm, 0.59 ± 0.12 mm, and 2.8 ± 0.2 times, with a receptacle length and width of 24.13 ± 2.07 and 2.81 ± 0.19 mm, respectively. Among the 40 previously known natural habitats of S. siliquosa, growth was confirmed only in Sepo, Sebang, and Bangpo. The causes for the declining S. siliquosa populations could be attributed to habitat changes due to construction, coastal road maintenance projects, habitat disturbances, and increased pollutants. Habitat substrate disturbances and changes were the main causes of the decrease in S. siliquosa growth. Studies on environmental factors and habitat degradation, growth related to environmental factors, mass cultivation, and the marine ecosystem restoration of S. siliquosa are needed. [ABSTRACT FROM AUTHOR]

We selected 15 sheep‐grazed sand pastures along a gradient of increasing grazing intensity to study the fine‐scale patterns of main biomass fractions (green biomass, litter) and that of plant species and functional groups (life forms and social behaviour types). We classified them into five grazing intensity levels based on stocking density, proximity to drinking and resting places and the number of faeces. We aimed to answer the following questions: (i) How does increasing intensity of sheep grazing affect the amount of green biomass, the species richness and their relationship in sand pastures? (ii) How does increasing intensity of sheep grazing affect the biomass of perennial and short‐lived graminoids and forbs? (iii) How does the disturbance value—expressed in the biomass ratio of disturbance‐tolerant and ruderal species—change along the gradient of grazing intensity? A unimodal relationship between green biomass and species richness was detected; however, the ordination (canonical correspondence analysis, CCA) showed no clustering of pastures subjected to the same levels of grazing intensity. Along the grazing intensity gradient we found an increasing trend in species richness and significant differences in green biomass (decreasing trend), litter (decreasing trend), graminoids (decreasing trend) and short‐lived forbs (increasing trend). We found an increasing amount of disturbance‐tolerant and ruderal species with increasing grazing intensity. We suggest that we might need to use multiple scales for sampling and a fine‐scale assessment of grazing intensity. Our findings might be instructive for pastures in densely populated regions, which are prone to the encroachment of disturbance‐tolerant and ruderal species. [ABSTRACT FROM AUTHOR]

Robust regulation is predictively investigated in time-delay models including uncertainties, non-zero reference, and disturbance. Hence, to handle the complexities induced because of the time-delays, disturbances, and uncertainties, enhancing the transient performance would be a main control goal. To this purpose, the required transient and steady-state specifications are achieved through an integral control structure with adjustable gains. The constraints on the signals and aims of the control algorithm are also described by some linear matrix inequalities. Guaranteeing the stability, a minimisation procedure is found to specify the predictive controller. Several simulations are performed to establish the effectiveness of the introduced plan in comparison with the similar strategy. [ABSTRACT FROM AUTHOR]

By incubating the soil without living roots in situ at two spruce forest sites, we simulated the effects of tree dieback and interrupted mycorrhizal associations following forest disturbance on the soil microbiome and phosphorus leaching. We observed the retreat of ectomycorrhizal fungi and increased proportion of saprotrophs without changes in community richness and the Shannon diversity index. This was accompanied by a pronounced decomposition of organic matter, associated with an increased activity of carbon-mining hydrolases and acid phosphatase. The nonexistent phosphorus uptake and immobilization by ectomycorrhizal associations led to its substantial increase in the soil, in the labile fractions, such as microbial biomass and water-soluble reactive phosphorus, but also in the fraction bound to organometallics (extractable by oxalate), and caused considerable phosphate leaching, as estimated using ion-exchange resin traps. The results show that the retreat of the root-specific environment, characterized by the input of available carbon and effective nutrient uptake and by the specific microbiome, has profound effects on phosphorus dynamics and loss. Furthermore, we suggest that ectomycorrhiza plays an equally important role in controlling phosphorus-mining from organic matter and subsequent immobilization and/or leaching from soils concurrently to its known role in nitrogen cycling and immobilization in spruce forests. [ABSTRACT FROM AUTHOR]

The objective of the invariant ellipsoid method is to minimize the smallest invariant and attractive set of a linear control system operating under the influence of bounded external disturbances. This study extends the application of this method to address the leader-following consensus problem. Initially, a linear control protocol is designed for the multi-agent system in the absence of disturbances. Subsequently, in the presence of bounded disturbances, by employing a similar linear control protocol, a necessary and sufficient condition is introduced to derive the optimal control parameters for the multi-agent system such that the state of followers converges to and remains in a minimal invariant ellipsoid around the state of the leader. [ABSTRACT FROM AUTHOR]

The forests of the Western Ghats (WG) of India are a highly diverse ecosystem though altered over time by human interference. The Northern Western Ghats (NWG) differ in bioclimatic and geological characteristics from the rest of the Western Ghats, featuring a mix of forested and open landscapes. Human activities such as shifting cultivation, cutting, lopping, periodic fire, constructions (road and dam), and mining have further increased their fragmentation, leading to a decrease in biodiversity. While the region has been extensively investigated for its floristic diversity, quantitative ecological studies are limited. This review seeks to identify research gaps and new research directions in the forest ecology of the NWG by compiling various periodical studies carried out in the region. It covers various works on vegetation types, species diversity and composition, and forest degradation due to anthropogenic activities. We provide compiled comparative vegetation types applicable to the region. The present review also discusses works carried out on forest areas under various protection regimes, such as legally protected areas, sacred groves, and private forests, using quantitative and remote sensing tools. We believe that understanding the NWG as an entire unit using uniform methods is essential, and this review serves as an important step in achieving this. It provides a comprehensive overview of the NWG, which can be used to plan out future research in this region. [ABSTRACT FROM AUTHOR]

Context: Disturbance interactions can create compound, novel effects across landscapes compared to individual disturbance events. However, little consensus exists regarding which mechanisms are important for controlling the interaction of two disturbances with similar climatic forcings in subalpine spruce–fir forests. Objectives: To investigate the importance of controls on disturbance interactions, we first outline potential mechanistic links between spruce beetle outbreaks and fires based on existing research. Second, we update the theoretical framework used to understand interactions between spruce beetles and fire in subalpine spruce–fir forests. Third, we provide expectations for potential interactions and suggest avenues for further research. Methods: We synthesized existing primary literature to categorize the potential mechanisms controlling the interactions between spruce beetles and fire. Results: We categorized mechanisms as either substrate mediated or environmentally mediated. Most research investigating the interaction between spruce beetle outbreaks and fire focuses on substrate mediation. There is a need to expand investigations of environmental mediating mechanisms due to the importance of climate and the ability for either disturbance to alter microclimatic conditions. Conclusions: Environmentally mediated mechanisms may better elucidate the interactions between spruce beetles and fire than substrate mediated mechanisms because both disturbances require specific environmental conditions, and both can alter environmental conditions that favor a second disturbance. Our understanding of how these mechanisms promote or constrain interactions is limited and warrants future study. Investigating these topics and expanding the scope of research both spatially and temporally may identify additional patterns that increase the predictability of this important disturbance interaction. [ABSTRACT FROM AUTHOR]

The paper presents a comparative analysis of the structural and functional characteristics of microbial communities of gray forest soil of fallow and intensively cultivated areas. The long-term anthropogenic impact with massive annual mineral fertilization when growing a monoculture of potatoes has led to degradation of the soil microbial system. A catastrophic decrease in the functional potential of the microbial system (environmental services) is shown using eco-exergy as a thermodynamic indicator of soil "health". [ABSTRACT FROM AUTHOR]

Due to the increasing needs on the performance of satellites, in particular optical satellites, microvibrations have become more and more important over the last years. Microvibrations affect a large number of satellites for both Earth observation and space observation missions. Further, microvibrations are also a concern for other missions with sensitive instruments like Fourier spectrometers, high-precision accelerometers or reference oscillators. In classical fields like structural dynamic engineering, management approaches have been established and implemented in all space projects. This paper presents a corresponding approach for the area of microvibrations. Focus is on the definition of all key elements needed to establish a microvibration control approach. This includes the establishment of microvibration budgets and associated summation rules. A systematic way for microvibration disturbance minimization is presented and rules for the application are defined. Specific emphasis is given to the definition of microvibration interface requirements and the associated control process. The concepts provided in this paper have been verified by tests performed in the frame of various satellite programs and studies. Tests related to the superposition of different noise sources are presented in here. • Spacecraft performance budgets related to microvibrations are established using adaptation of standard ECSS rules. • Microvibration interface requirements are defined using an optimized margin approach. • Microvibration requirement definition and verification concepts are defined for typical satellite architectures. • Assuming linear summation of different microvibration noise sources overestimates the performance impact. [ABSTRACT FROM AUTHOR]

Copyright of Control Theory & Applications / Kongzhi Lilun Yu Yinyong is the property of Editorial Department of Control Theory & Applications and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Bosque (03048799) is the property of Facultad de Ciencias Forestales, Universidad Austral de Chile and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this paper, input-to-state stability (ISS) properties of perturbed systems with event-triggered receding horizon control (RHC) schemes are studied. Two event-triggered control schemes, which are the event-triggered quasi-infinite RHC (EQRHC) and the event-triggered dual-mode RHC (EDRHC) strategies, respectively, are considered. In the EQRHC scheme, an optimal control problem (OCP) should be considered at triggering time and the event is triggered if the error between the actual system state and the optimal system state violating a threshold. While in the EDRHC strategy, an OCP is only solved outside the terminal region and a local control law will be used inside the terminal region. The corresponding event condition is redesigned based on if the system state enters the terminal region or not. The event-triggering condition outside the terminal region is the same with that of the EQRHC scheme and the event-triggering condition inside the terminal region is proposed based on the difference between the actual system state and the predictive system state. Sufficient conditions of feasibility are proposed and ISS properties of both event-triggered control schemes are studied, respectively. At last, numerical simulations show the validity of the proposed methods. [ABSTRACT FROM AUTHOR]

In this paper, a novel fractional‐integer integral type sliding mode technique for control and generalized function projective synchronization of different fractional‐order chaotic systems with different dimensions in the presence of disturbances is presented. When the upper bounds of the disturbances are known, a sliding mode control rule is proposed to insure the existence of the sliding motion in finite time. Furthermore, an adaptive sliding mode control is designed when the upper bounds of the disturbances are unknown. The stability analysis of sliding mode surface is given using the Lyapunov stability theory. Finally, the results performed for synchronization of three‐dimensional fractional‐order chaotic Hindmarsh‐Rose (HR) neuron model and two‐dimensional fractional‐order chaotic FitzHugh‐Nagumo (FHN) neuron model. [ABSTRACT FROM AUTHOR]

The tremendous growth of global network, Internet penetration, created an undeniably profitable avenue for marketers and business owners to get reduced cost and high advertising revenue. A large number of advertisements were published by marketers on its way today, followed by negative effects on users. This research studies today's Internet advertisements and negative effects of online advertisements on Web users. The paper aims to analyse online factors influencing users' perception and attitude towards advertising on the Internet. The online survey was conducted among 150 active Internet users from public universities in India. The findings reveal the dramatical growth of online advertisements over the past 4-5 years. Most of the respondents find online advertisements distractive/intrusive, confirming that almost all privacy issues on the Internet and social sites are due to Internet advertising. Also, the study establishes that the attitude of users towards Internet advertisements is non-positive, especially popups, video ads and retargeted advertisements are the most disturbing ones among online advertisements. The research concluded that the overall perception of Internet users about online advertisements is neutral, suggesting that it should be improved. [ABSTRACT FROM AUTHOR]

The LQR (linear quadratic regulator) control problem subject to singular system constitutes a optimization problem in which one must be find an optimal control that satisfy the singular system and simultaneously to optimize the quadratic objective functional. In this paper we establish a sufficient condition to obtain the optimal control of discounted LQR optimization problem subject to disturbanced singular system where the disturbance is time varying. The considered problem is solved by transforming the discounted LQR control problem subject to disturbanced singular system into the normal LQR control problem. Some available results in literatures of the normal LQR control problem be used to find the sufficient conditions for the existence of the optimal control for discounted LQR control problem subject to disturbanced singular system. The final result of this paper is in the form a method to find the optimal control of discounted LQR optimization problem subject to disturbanced singular system. The result shows that the disturbance is vanish with the passage of time. [ABSTRACT FROM AUTHOR]

A robust model predictive control algorithm is proposed for a constrained nonlinear system with bounded persistent disturbance in this paper. Based on polytopic descriptions that include the initial system, the proposed algorithm computes a series of multi‐step control sets offline and the convex combination of them online respectively by solving convex optimization problems described by a few linear matrix inequalities. At each sampling time, the control moves satisfying the control constraint are obtained and implemented in the system. The controller design is illustrated with two examples. The proposed MPC controller achieves closed‐loop input‐to‐state (practical) stability (ISS/ISpS) and strong robustness in respect of bounded persistent disturbances. [ABSTRACT FROM AUTHOR]

Ecological succession – how biological communities re‐assemble and change over time following natural or anthropogenic disturbance – has been studied since the birth of ecology, and the resulting theoretical framework underpins many aspects of the discipline. Recently, the mechanistic basis of classic succession theory has been advanced by studies of plant and microbial interactions, functional traits, and retrogressive stages of ecosystem development. This special issue brings together a series of papers that highlight these contemporary novel approaches and how our understanding of ecological succession has advanced.Four key themes emerge from the issue: (a) generalizations about succession, (b) the influence of dispersal and habitat size on successional trajectories, (c) changes in plant functional traits during succession, and (d) belowground community interactions during long term during ecosystem development.Synthesis. The articles in the special issue highlight novel perspectives on succession theory, revealing the importance of historical contingency, disturbance severity, dispersal limitation, functional traits, and belowground community processes in determining patterns of ecosystem development. Together, they reinforce the importance of ecological succession in understanding the response of plant and microbial communities to disturbance in a changing world. The articles in the special issue highlight novel perspectives on succession theory, revealing the importance of historical contingency, disturbance severity, dispersal limitation, functional traits, and belowground community processes in determining patterns of ecosystem development. Together, they reinforce the importance of ecological succession in understanding the response of plant and microbial communities to disturbance in a changing world. [ABSTRACT FROM AUTHOR]

Resilience is a well‐used term in many disciplines, but inconsistently or little applied in river geomorphology and river science. Recent developments in ecosystem ecology conceptualize resilience as comprising system resistance to, and recovery from disturbance. The objectives of this paper are to consider how the concept of resilience in this bivariate form applies to river geomorphology and provide a framework for bridging the disciplines of ecology and geomorphology within the setting of river management, using principles of resilience. River geomorphology sets the physical template upon which lotic processes act, thus, understanding the resilience of this template is critical. The importance of consistency in defining the principles of resilience thinking within the context of river science and management is important especially when promoting ecosystem resilience as a river management goal. The application of resilience thinking with respect to river habitat is provided through a series of examples from Australian and New Zealand river systems. Aim: How is the concept of resilience applied to river geomorphology, and what does a geomorphologically resilient river look like? [ABSTRACT FROM AUTHOR]

The rotational symmetry connection between the Species-Area Relationship (SAR) and Endemics-Area Relationship (EAR) was discovered in the frame of Species-Area Theory. In this paper, this paired connection was applied into the impact of variation of number of species and area and dynamic change of species-abundance distribution on the curve shape of SAR and EAR, which can be integrated into the assessment of Natural Protected Areas and Ecological Restoration Projects. The results indicate that the underestimate or overestimate of total number of species can lead to the underestimate or overestimate of extinction rate, while the reduction or expansion of area can lead to the increase or decrease in extinction rate. In addition, the species-abundance distribution change of community causes the shape tuning of SAR and EAR, which leads to inconsistent change of extinction rate. Thus, this SAT frame can be used as a qualitative tool in conservation and restoration management. [ABSTRACT FROM AUTHOR]

The aim of the research paper is to develop algorithms for manufacturers' agents that would allow them to sequence their own operation plans and to develop a multi-agent infrastructure to allow operation pair agents to cooperatively adjust the timing of manufacturing operations. The scheduling problem consisted of jobs with fixed process plans and of manufacturers collectively offering the necessary operations for the jobs. Manufacturer agents sequenced and pair agents timed each operation as and when required. Timing an operation triggered a cascade of conflicts along the job process plan that other pair agents would pick up on and would take action accordingly. The conventional approach performs conflict resolution in series and manufacturer agents as well as pair agents wait until they are allowed to sequence and time the next operation. The limiting assumption behind that approach was systematically removed, and the proposed approach allowed manufacturers to perform operation scheduling in parallel, cutting down tenfold on the computation time. The multi-agent infrastructure consists of the Protégé knowledge base, the Pellet semantic reasoner and the Workflows and Agent Development Environment (WADE). The case studies used were the MT6, MT10 and LA19 job shop scheduling problems; and an industrial use case was provided to give context to the manufacturing environment investigated. Although there were benefits from the decentralised manufacturing system, we noted an optimality loss of 34% on the makespans. However, for scalability, our approach showed good promise. [ABSTRACT FROM AUTHOR]

The boundary control problem of a cantilever Euler- Bernoulli is considered in this paper. If the control at the right end of the beam is of the form w xxx (1, t) = u(t − τ) + r(t), where τ > 0 is the input time-delay and r(t) is an unknown external disturbance, a dynamic feedback control strategy based on the methods of partial state predictor and active disturbance rejection control is used to stabilise the system. Under some assumptions on r(t), it is proven that the state of the system exponentially converges to and stays in the compact set . The radius ϵ is determined by the time-delay τ and the properties of r(t). The simulations are provided to compare the influence of τ and r(t) on the radius ϵ. [ABSTRACT FROM AUTHOR]

In this paper, the uncertainty and disturbance estimator (UDE)-based robust control is applied to the control of a class of nonaffine nonlinear systems. This class of systems is very general and covers a large range of nonlinear systems. However, the control of such systems is very challenging because the input variables are not expressed in an affine form, which leads to the failure of using feedback linearization. The proposed UDE-based control method avoids the inverse operator construction, which might result in the control singularity problem. Moreover, the general assumption on the uncertainty and disturbance term is relaxed, and only its bandwidth information is required for the control design. The asymptotic stability of the closed-loop system is established. The proposed approach is easy to be implemented and tuned while bringing very good robust performance. The important features and performance of the proposed approach are demonstrated through both simulation studies and experimental validation on a servo system with nonaffine uncertainties. [ABSTRACT FROM PUBLISHER]

This paper is concerned with the robust adaptive synchronization problem for unified chaotic systems with parameter variation, system uncertainties, and external disturbances. By combining adaptive method and positive time-varying integral functions, novel adaptive synchronization schemes are proposed. It is shown that the synchronization errors between the drive and response chaotic systems converge to zero asymptotically. Finally, illustrative examples about Lorenz chaotic system, Chen chaotic system, and Lü chaotic system are provided to demonstrate the effectiveness and applicability of the proposed design method. [ABSTRACT FROM AUTHOR]