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Distributed time-varying formation technology for multi-agent systems is recently become a research hotspot in formation control field. However, the formation reconfiguration control technology for agents that randomly appeared to fail during maneuvers is rarely studied. In this paper, the topological relations between intelligence are designed by graph theory to simplify the cooperative interaction between multi-agent systems. Moreover, this paper constructs the time-varying configuration of the target formation based on the rigidity graph theory and leader–follower strategy. Drawing on the establishment of the expert experience database in a collaborative process, we innovatively propose the establishment of a graphic library to help the multi-agent system quickly form an affine transformation as soon as it is disabled. Secondly, the improved Hungarian algorithm is adopted to allocate the target point when the first failure occurs. This algorithm incorporates a gradient weighting factor from the auction algorithm to improve the speed of system reconfiguration with minimum path cost. On this basis, a distributed multi-agent control law based on consistency theory is established, and the system's stability can be guaranteed via Lyapunov functions. Finally, the simulation results demonstrate the feasibility and effectiveness of the proposed formation reconfiguration control algorithm in a collaborative environment. [ABSTRACT FROM AUTHOR]

In this paper, the formation control problem for a multi-agent system is studied. Two new robust control algorithms for serial and parallel formations respectively are proposed, which take the constraints of limited field of view into consideration. Without the need for any global information, the only relative information required is distance and bearing angle, thus is easy to implement with onboard directional sensors. It is then demonstrated how complex formations can be realized by combining the proposed basic controllers. Finally, effectiveness of the proposed algorithms is illustrated by numerical examples. [ABSTRACT FROM AUTHOR]

Temperature-stable and low-loss microwave dielectrics based on the MgO-TiO 2 system with nominal formation Mg n +1 Ti n O 3 n +1 ( n = 5, MT) were prepared via the conventional solid-state reaction method. Ca 0.8 Sr 0.2 TiO 3 (CST) was chosen as a τ f compensator for matrix MT to form the composite ceramics (1- x )Mg 6 Ti 5 O 16 - x Ca 0.8 Sr 0.2 TiO 3 (0.10 ≤ x ≤ 0.26, MT-CST). The effects of CST additions on the phase composition, defect relaxation behavior, and microwave dielectric properties of MT were investigated. It revealed that undoped MT was basically consisted of MgTiO 3 as a major phase and Mg 2 TiO 4 as a minor phase, and such two phases coexisted well with CST additions. Interestingly, τ f could be tuned close to zero (−1.28 ppm/°C) for the MT-CST ceramics at x = 0.22, accompanied with a high Q×f value ~ 74,200 GHz and a proper ε r ~ 20.25 (9.90 GHz). These materials possessed a good potential for applications in microwave components and devices. Meanwhile, significant relaxation phenomena were observed in all the MT-CST samples using dielectric spectroscopy and thermally stimulated depolarization current (TSDC) techniques. The oxygen-vacancy-related defects, shown as ( T i T i ′ )-( V O • • ) dipoles and V O • • , were the main types of defects in MT-CST, which was responsible for the relaxation behavior; meanwhile, the defect concentrations increased with the increase of CST content, thus resulting in the increase of dielectric loss at low and high frequencies. [ABSTRACT FROM AUTHOR]

Copyright of Context / Kontekst is the property of Institute of Macedonian Literature 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.)

The identification of biblical Ziklag has plagued scholars for over 150 years. Fourteen potential sites have been identified, and there is yet to be a consensus. Based on geographical, archaeological, textual, and chronological considerations, it will be argued that Khirbet er-Ra'i, the most recent site proposed, is the best candidate for biblical Ziklag. [ABSTRACT FROM AUTHOR]

The word 'health' is highly polysemous, and many attempts have been made to define its meaning in terms of actual use and to create a workable and even universal concept of health (Balog 1978; Boruchovitch & Mednick 2002). However, though the meaning of 'health' has been debated extensively, as well as the metaphorical conceptualizations of illness (e.g., Sontag 1978), there has been little treatment of how health is metaphorically conceptualized. This article investigates the meaning of the word 'health' in the United States and the United Kingdom, through a search on websites based on an examination of concordances in the Corpus of Global Web-Based English (GloWbE). It focuses on the senses emerging from metaphorical cultural conceptualizations. Recent developments in Conceptual Metaphor Theory (Kövecses 2005; Yu 2009) and Cultural Linguistics (Palmer 1996; Sharifian 2011) have increased the focus on the interaction between cognition and culture. I present an analysis of the conceptual metaphors, proposition schemas, and image schemas that converge to form a cultural model for health within these speech communities revealing, for example, that one model sees health in terms of a manageable valuable commodity, which may contribute to health behaviors such as self-tracking and observation, as discussed by Lupton (2016). [ABSTRACT FROM AUTHOR]

This paper sought to analyze the possible disparity in the appropriation of tax benefits granted to incentivized debentures (in the form of Law No. 12,431/2011) via price mechanism. According to economic theory, markets under normal operating conditions do not present room for arbitrage, and assets endowed with the same risk conditions should not present incompatible values. Therefore, it is expected that the spread exhibited by incentivized debentures in the secondary market is equivalent to that of regular debentures when adjusted by the respective tax and risk factors. Thus, a methodology was proposed for evaluating the parameters that potentially define the remuneration of debentures, in order to isolate the effect of this tax incentive to determine its impact on price formation. The results pointed to the statistical irrelevance of this parameter, assuring market conformity to the no-arbitrage theory and preventing the rejection of the hypothesis of effective appropriation of the tax benefit by the debenture issuer. [ABSTRACT FROM AUTHOR]

Deep space missions are recently gaining increasing interest from space agencies and industry, their maximum exponent being the establishment of a permanent station in cis-lunar orbit within this decade. To that end, autonomous rendezvous and docking in multi-body dynamical environments have been defined as crucial technologies to expand and maintain human space activities beyond near Earth orbit. Based on analytical and numerical formulations of the relative dynamics in the Circular Restricted Three Body Problem (CR3BP), a family of optimal, linear and nonlinear, continuous and impulsive, guidance and control techniques are developed for the design of end-to-end rendezvous trajectories between co-orbiting spacecraft in this multi-body dynamical environment. To this end, several modern control techniques are effectively designed and adapted to this problem, with particular emphasis on the design of low cost rendezvous manoeuvres. Finally, the designed hybrid rendezvous strategies, combining both discrete and continuous control techniques, are effectively tested and validated under several start-to-end deep space testbench mission scenarios, where their performance is compared and quantitatively assessed with a set of performance indices. [ABSTRACT FROM AUTHOR]

The tug₂ guz-za /tug₂guz.za is a cloth attested in different spellings from the 3rd to 1st millennia BCE that has received diverse translations. Evidence from Ur III textile production texts, reconstructions based on experimental data, and lexical lists now converge to suggest that the cloth was defined by its thick weft. Although the tug₂ guz-za /tug₂guz.za has traditionally been connected to the Zottenrock of Mesopotamian visual media via the adjective guz(-za) 'bristly, wire-haired,' no independent evidence of shagginess has been found for the textile. Instead, this contribution demonstrates that there is another guz-za meaning 'bright red' that was applied to textiles and wool in the lexical lists of the 2nd millennium BCE, suggesting that the tug₂ guz-za /tug₂guz.za was conceived of as a red cloth at least in some periods. [ABSTRACT FROM AUTHOR]

This article investigates the distributed event‐triggered affine formation maneuver control problem for multiple underactuated surface vessel (USV) systems with positive minimum inter‐event times (MIET). Unlike common formation control methods that only ensure the formation system to keep a fixed geometric shape, the proposed scheme enables multiple USVs maneuver as a group in translation, shearing, rotation, or combinations of them. The proposed control strategy is composed of two parts. First, a distributed event‐triggered observer (DETO) is proposed to observe the time‐varying target formation under the lack of global leaders' information and govern the inter‐vessel communications among the formation group. Besides, the MIET of the designed communication strategy is proved to be strictly positive and computable from formation configurations and control parameters. With these guarantees, the maximum communication frequency can be known in advance. Then, upon the DETO signals, the adaptive local tracking controller is subsequently synthesized for each vessel to realize the target formation track. Rigorous theoretical analysis and simulation results are finally conducted to verify the validness and effectiveness of the proposed algorithm. [ABSTRACT FROM AUTHOR]

Copyright of Archiv für Papyrusforschung und Verwandte Gebiete is the property of De Gruyter 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.)

This paper investigates the issues of iterative learning algorithm-based robust thruster fault reconstruction and reconfigurable fault-tolerant control for spacecraft formation flying systems subject to space perturbations. Motivated by sliding mode methodology, a novel iterative learning observer (ILO) was developed to robustly reconstruct the thruster faults. Based on the fault signals obtained from the ILO, a learning output–feedback fault-tolerant control (LOF2TC) approach was explored such that the closed-loop spacecraft formation configuration was accurately maintained in the presence of space perturbations and thruster faults. Numerical simulations were employed to demonstrate the effectiveness and superiority of the proposed ILO-based fault-reconstructing approach and LOF2TC-based configuration maintenance approach for spacecraft formation flying systems. [ABSTRACT FROM AUTHOR]

The aim of the paper is to review the Proto-Indo-European origin of neuter collective nouns in *-iiom. This type of collectives was highly productive in most Slavic languages, whereas its attestation in other Indo-European languages is generally residual. Some traces of collective nouns in *-iio̯ m are to be distinguished in Indo-Aryan languages (especially in Vedic), Germanic (especially in Old Nordic), Baltic (especially in Old Prussian), Tocharian, Ancient Greek and probably in Armenian. The archaic character of these neuter collectives can additionally be confirmed by a number of corresponding feminine collective nouns, e.g. PIE. *bhreh2tri̯ó m n. coll. 'group of brothers; brotherhood, fraternity' (attested in Indo-Aryan, Slavic and Tocharian) and PIE. *bhréh2tri̯e h2 f. coll. 'id.' (registered in Greek, Baltic and Slavic); PIE. *gu̯ou̯i̯ó m n. coll. 'herd of cows' (in Vedic and Belorussian) vs. PIE. *guóuiie h2 f. coll. 'id.' (attested in Vedic, East Baltic and Laconian Greek). The variation between the neuter and feminine collective nouns is well observed on the basis of Indo-Aryan, Germanic and Slavic lexical data. [ABSTRACT FROM AUTHOR]

This article studies optimal leader‐follower affine formation control for linear multi‐agent systems, which has more formation flexibility due to the usage of stress matrices. First, based on the inverse optimality strategy, an affine formation control law is designed to drive the followers to their target positions, in which a corresponding performance index is minimized. Next, to minimize a prespecified performance index, another class of optimal affine formation control law is proposed by using a cooperative estimator. The design of the cooperative estimator is based on the proportional‐integral feedback which estimates the target position of each follower. Under the proposed control law, the followers achieve the target formation and the given performance indices are guaranteed to be optimal at the same time. Finally, the corresponding simulations are carried out to verify the effectiveness of the presented approaches. [ABSTRACT FROM AUTHOR]

Copyright of Kadmos is the property of De Gruyter 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.)

An affine formation tracking problem of multiple mobile agents is studied in this work. Each agent in the system is modeled as an underactuated kinematic rigid body with nonholonomic constraints, maneuvering on the special Euclidean group (SE(3)). A controller is designed for each agent directly on the corresponding Lie algebra of SE(3). Moreover, only local information accessible to each agent in its body-fixed frame is involved. The proposed control protocol can be implemented under both directed and undirected topologies. In addition, for directed graphs, an algorithm is proposed to realize the formation under switching topologies. Finally, numerical simulations are given to illustrate the efficiency and feasibility of the proposed results. [ABSTRACT FROM AUTHOR]

This study examines headedness in different nominalisation processes in Yoru'ba'. This research aims to investigate possible unification of head analysis in Yoru'ba' nominalisation. Three major word formation strategies exist in Yoru'ba', namely, affixation, reduplication and nounnoun compounding (N-N compounding henceforth). The morphosyntactic relationship among these three, in respect to a unifying analytical goal, has not been fairly considered. Operation merge, with other principles of the Minimalist Programme, is selected to validate my claim about the unified analysis of headedness in Yoru'ba'. This paper employs the qualitative method of data collection. Data were sourced from both primary and secondary means. I claim that there exists a parallel morphosyntactic structure for the three nominalisation processes in Yoru'ba'. I establish that the three nominalisation structures have the same syntactic representation as far as their headedness and their internal syntax is concerned. Findings in this study show that, firstly, prefixes, reduplicant and the first noun in an N-N compounding are the head. Secondly, they all occupy the same parallel positions in their varying structures. [ABSTRACT FROM AUTHOR]

To drive a group of agents to maneuver continuously with the desired collective forms, this paper addresses a distributed formation maneuver control problem of directed networked high-order multi-agent systems in arbitrary dimensions. Unlike the conventional methods where the target formation is time invariant, we propose an affine formation method based on the properties of affine transformation, in which the target formation can be time-varying and affinely transformed from the given nominal formation. This paper provides and proves a sufficient and necessary condition of achieving the directed graphical affine localizability, and it only needs that the leaders have a generic configuration and the followers are accessible to the subset of leaders. To achieve the whole formation maneuvers, assume that the leaders decide the whole formation's maneuver actions, then the control algorithms of the arbitrary-order integrator followers are proposed to track the time-varying target formation and the global convergence of tracking errors is also proved. Furthermore, this paper studies the practical problems of formation maneuvers when existing non-uniform time delays. Finally, both two-dimensional and three-dimensional simulation examples are given to demonstrate the effectiveness of theoretical results. [ABSTRACT FROM AUTHOR]

Copyright of Domínios de Lingu@gem is the property of Dominios de Lingu@gem 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.)

This article investigates the derivational processes involving nouns in Shinyiha. It focuses on two main issues: derivation by attaching an affix that changes meaning and a word category (for example, from verb to noun), and derivation by prefixing a stem which has its inherent class prefix. The study also identifies the use of associative phrases to express meanings which could be expressed by derived nouns. It reveals that noun derivation in Shinyiha is a complex phenomenon which involves both simple and complex verbs. It is affected by adding either a prefix, a prefix plus a nominalising suffix or a prefix plus verb extension suffixes. It is noted that the final vowels attached to deverbatives are not default vowels; they contribute to the meaning of the derived noun. The study reveals that one nominalising suffix may induce multiple meanings, depending on the nature of the verb root. The same meaning may be expressed by different suffixes. In addition, associative constructions can occur with infinitives to express agentiveness to compensate for nouns that cannot be derived in a regular way. [ABSTRACT FROM AUTHOR]

The robust output formation problems are considered for uncertain multi-agent systems. The dynamic of each agent is constructed by a nominal system combined with uncertainties and external disturbances. Based on the interaction topology among agents, a robust time-invariant formation controller is proposed. The designed controller consists of two parts: a nominal output feedback formation controller and a robust compensator. The nominal controller is designed to achieve the desired output formation, and the robust compensator is introduced to restrain the influence of the uncertainties and disturbances. An output formation feasible condition is proposed, and it is proven that the output formation error can be made arbitrarily small. Finally, a simulation example is provided to illustrate the obtained theoretical results. [ABSTRACT FROM AUTHOR]

The aim of the paper is to discuss the etymological and semantic aspects of the Indo-European root *lerd-. There are numerous reflexes of the root in verbal and nominal formations in IndoAryan, hitherto unnoticed in etymological research. I intend to explain Sanskrit lardayati 's/he loads' as a causative verb reflecting IE. *lordéieti (originally 's/he makes someone carry a burden'); further, I proceed to analyze the totality of nominal forms attested in Indo-Aryan, Celtic, Germanic, Armenian, and Greek from the point of view of Indo-European word-formation. Finally, I discuss the semantic aspects of the issue, concluding that the Indo-European root *lerd-apparently underwent the following semantic changes: 'to carry a burden' > 'to bend backwards due to a heavy burden' > 'to contort, deform'. [ABSTRACT FROM AUTHOR]

This paper examines the count-mass distinction in Terena (Aruák, Brazil) by focusing on plural marking availability, numeral and quantifier distribution and cardinal versus volume interpretation in quantity judgment tests. The data collected from the initial research of these features in Terena reveals the relevancy of the count-mass distinction in the language with some signature properties: (i) only count nouns can be directly combined with numerals; (ii) only count nouns can be used with the quantifier êno with the interpretarion of many individuals rather than a large quantity; and finally, (iii) only count nouns can express cardinality of individuals in a comparative sentence such as John has more N than Peter. Plural morpheme distribution is unsuitable for distinguishing count from mass nouns (such as in English) since mass nouns can be pluralized in Terena, provided noun denotations have individuals to allow for number rather than volume quantity interpretation. [ABSTRACT FROM AUTHOR]

A scrutiny of Northern Sotho Terminology and Orthography No. 4 of 1988 (T&O) and a survey of some Northern Sotho dictionaries make one wonder if rules are always followed in the lemmatisation of Northern Sotho loanwords. Northern Sotho, like any other language, has rules governing its spelling and orthography, thanks to T&O. The T&O and other editions of Northern Sotho terminology and orthography tried to dictate and explain the spelling and orthography rules to be followed in the writing of Northern Sotho words (native and adopted words). The spelling rules laid down are sometimes contradictory. This article shows the inconsistencies that prevail in the spelling of some Northern Sotho loanwords, arguing that some of these words are not fully adapted to the Northern Sotho spelling orthography. Writing a 'sotho-ised' version of a foreign word is not that simple; rules are sometimes broken (or rather bent) to suit the writer. Most of the data comes from the Northern Sotho Terminology and Orthography No. 4 of 1988 and Northern Sotho dictionaries. [ABSTRACT FROM AUTHOR]

This study investigates the robust formation tracking problems for uncertain multi‐agent systems(MASs). The leader is assumed to be linear case and the dynamics of the followers can be modelled as a high‐order linear system with heterogeneous uncertainties and external disturbances. Only part of the followers can get the states of the leader and the control input of the leader cannot be obtained by any followers. Based on the relative information among agents, robust formation tracking protocols are proposed to achieve the desired formation tracking. It can be proven that the formation tracking error can be made arbitrarily small if the formation tracking feasibility condition holds. Finally, a simulation example is provided to illustrate the obtained theoretical results. [ABSTRACT FROM AUTHOR]

Presents a linguistic analysis of terms and passages in the context of the ocean voyage of the main character of the epic `Beowulf.' Description of the epic plot; Semantic range posited for eoletes; Verification of the nominal formation of aelaet in various meanings in Old English; Etymology of underlying form in Beowulf 224.

For the tracking control problems of affine formation maneuvers with discrete leader-following multi-agent systems, various distributed control schemes based on the directed graphs are designed in this paper. Consider the single and double-integrator models, different types of formation maneuvers can be achieved subject to the states of leaders with the novel characteristic of affine localizability. Meanwhile, the properties of affine transformation and signed Laplacian are introduced, which simplify the structures of controllers with distinct constraints to a great extent. Moreover, the convergence analysis of proposed protocols is proven. Static, constant and time-varying target formations can be tracked successfully. In the end, corresponding numerical simulations are carried out to certify the validity of theoretical results. [ABSTRACT FROM AUTHOR]

This paper studies the affine formation control problem for a group of flying satellites with the performance of obstacle avoidance. Assuming that leader satellites can detect the locations of obstacles, we first investigate how to plan advisable trajectories for leader satellites such that they can smoothly pass through some specific types of obstacles by tracking the planned trajectories. Secondly, to enable follower satellites pass through the obstacles by following leader satellites' moving trajectories, a relationship between leader satellites' positions and follower satellites' desired positions is established by employing the affine formation approach. Then, a distributed formation control algorithm is proposed, which ensures all follower satellites converge to their desired positions. Moreover, the uncertainties and disturbances are considered in each satellite's motion dynamics, and are compensated by the designed adaptive laws. Finally, simulation examples are provided to validate the effectiveness of the proposed control algorithms. [ABSTRACT FROM AUTHOR]

Numerous Ancient Greek terms for 'cicada' are attested in the lexicon of Hesychius of Alexandria (5th c. AD); these are explained here from the morphological and etymological point of view. Some of them are dialectal items, representing Achaean (in Cyprus and Pamphylia) or Doric (e.g. Laconian λιγάντωρ m. 'male cicada'). Other Hesychian words for 'cicada' demonstrate obvious features of Attic-Ionic speech. New explanations are suggested for some of the rare appellatives belonging here, including Gk. dial. κίκους m. 'young cicada' and κίξιος m. 'cicada'. Finally, possible motivation for the attested words is carefully discussed. [ABSTRACT FROM AUTHOR]

This paper deals with the traditional distinction between verbs and nouns, in which any verbal form is assigned to one of the seven constant verbal patterns (binyanim), while a nominal form might be assigned to various basic patterns which differ according to its root class (gizrah). It is suggested that this distinction, which is customarily applied in Hebrew grammars since the Middle Ages, is derived from an abstract implicit concept of the notion of the morpheme, which could be deduced from the stances expressed in the traditional discussion on the number of the Hebrew verbal patterns. Given that there is a fundamental semantic difference between the verbal system and the nominal system, this concept of the morpheme, based on the semantic profile of a given word, entailed the distinction between verbs and nouns. [ABSTRACT FROM AUTHOR]

The formation of primary olefins from dimethyl ether (DME) was studied over ZSM‐5 catalysts at 300°C using a novel step response methodology in a temporal analysis of products (TAP) reactor. For the first time, the TAP reactor framework was used to conduct single‐ and multiple‐step response cycles of DME (balance argon) over a shallow bed with the continuous flow panel. Propylene is the major primary olefin and portrays an S‐shaped profile with a preceding induction period when it is not observed in the gas phase. Methanol and water portray overshoot profiles due to their different rates of generation and consumption. DME effluent shows a rapid rise halfway to its steady‐state value leading to a slow rise thereafter because of its high desorption rates followed by subsequent reactions involving DME in further steps during the induction period. To analyze the experimental data quantitatively, nine reaction schemes were compared, and kinetic parameters were obtained by solving a transient plug flow reactor model with coupled dispersion, convection, adsorption, desorption, and reaction steps. The methoxymethyl pathway involving dimethoxyethane and methyl propenyl ether gives the closest match to experimental data in agreement with recent density functional theory studies. Gaseous dispersion coefficients of ca. 10−9 m2 s−1 were obtained in the TAP reactor. The novel experimental data validated against the transient kinetic model suggests that after the formation of initial species, the bottleneck in propylene formation is the transformation of the initial C–C bond, that is dimethoxyethane formed initially from DME and methoxymethyl groups. DME adsorption on ZSM‐5 catalyst generates surface methoxy groups, which further react with the feed to give methoxymethyl groups. These methoxymethyl groups are regenerated through a series of reactions involving intermediates such as dimethoxymethane and methyl propenyl ether before propylene formation. [ABSTRACT FROM AUTHOR]