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Social animals have the remarkable ability to organize into collectives to achieve goals unobtainable to individual members. Equally striking is the observation that despite differences in perceptual-motor capabilities, different animals often exhibit qualitatively similar collective states of organization and coordination. Such qualitative similarities can be seen in corralling behaviors involving the encirclement of prey that are observed, for example, during collaborative hunting amongst several apex predator species living in disparate environments. Similar encirclement behaviors are also displayed by human participants in a collaborative problem-solving task involving the herding and containment of evasive artificial agents. Inspired by the functional similarities in this behavior across humans and non-human systems, this paper investigated whether the containment strategies displayed by humans emerge as a function of the task’s underlying dynamics, which shape patterns of goal-directed corralling more generally. This hypothesis was tested by comparing the strategies naïve human dyads adopt during the containment of a set of evasive artificial agents across two disparate task contexts. Despite the different movement types (manual manipulation or locomotion) required in the different task contexts, the behaviors that humans display can be predicted as emergent properties of the same underlying task-dynamic model.

The target-encirclement guidance problem for many-to-one missile-target engagement scenario is studied, where the missiles evenly distribute on a target-centered circle during the homing guidance. The proposed distributed target-encirclement guidance law can achieve simultaneous attack of multiple missiles in different line-of-sight directions. Firstly, the decentralization protocols of desired line-of-sight angles are constructed based on the information of neighboring missiles. Secondly, a biased proportional navigation guidance law that can arbitrarily designate the impact angle is cited. The missiles can achieve all-aspect attack on the target in an encirclement manner by combining the biased proportional navigation guidance law and dynamic virtual targets strategy. Thirdly, the consensus protocol of simultaneous attack is designed, which can guarantee that all missiles’ time-to-go estimates achieve consensus asymptotically, and the convergence of the closed-loop system is proved strictly via the Lyapunov stability theory. Finally, numerical simulation results demonstrate the performance and feasibility of the proposed distributed target-encirclement guidance law in different engagement situations.

This paper addresses a multi-pursuer single-evader pursuit-evasion game where the free-moving evader moves faster than the pursuers. Most of the existing works impose constraints on the faster evader such as limited moving area and moving direction. When the faster evader is allowed to move freely without any constraint, the main issues are how to form an encirclement to trap the evader into the capture domain, how to balance between forming an encirclement and approaching the faster evader, and what conditions make the capture possible. In this paper, a distributed pursuit algorithm is proposed to enable pursuers to form an encirclement and approach the faster evader. An algorithm that balances between forming an encirclement and approaching the faster evader is proposed. Moreover, sufficient capture conditions are derived based on the initial spatial distribution and the speed ratios of the pursuers and the evader. Simulation and experimental results on ground robots validate the effectiveness and practicability of the proposed method. National Research Foundation (NRF) Accepted version This work was supported in part by the ST EngineeringNTU Corporate Laboratory through the NRF Corporate Lab@University Scheme and in part by the National Natural Science Foundation of China under Grant 61720106011.

This paper proposes a coordinate-free controller to drive a mobile robot to encircle a target at unknown position by only using range measurements. Different from the existing works, a backstepping based controller is proposed to encircle the target with zero steady-state error for any desired smooth pattern. Moreover, we show its asymptotic exponential convergence under a fixed set of control parameters, which are independent of the initial distance to the target. The effectiveness and advantages of the proposed controller are validated via simulations.

THE PRESENT PAPER confronts the general question of the lawfulness of forestalling both potential owners from originally appropriating unowned land and actual owners from exiting their property. This kind of forestalling, which poses problems for libertarian theory, consists in a pattern of appropriation that allegedly puts a given individual in such a position that it is impossible for him to appropriate an unowned tract of land or to exit his property without trespass.

Japan has been regarded by all mainstream International Relations theories as a status quo power intent on pursuing an immobilist international strategy toward China characterized by hedging rather than any move to active balancing. This paper challenges these assumptions and asks whether Japan will, or indeed already is, moving toward active balancing. The paper does so by reinterpreting the very assumptions of those theoretical perspectives that predict only hedging and by drawing on fresh empirical evidence. It argues that the conditions that are thought to encourage hedging behavior—the predictability of other states’ intentions, the malleability of intentions through engagement, domestic preferences that obviate balancing, and a favorable offense-defense balance—are now deteriorating in the case of Japan’s strategy toward China. Japanese policy-makers over the last decade have experienced an accelerated decline in their confidence to read China’s intentions and to mold these, to the point that China is now regarded as an increasingly malign actor. Japan’s own domestic regime change, paralleling that of China, has released Revisionist forces that favor the cessation of the “underbalancing” of China. Very significantly, Japanese policy-makers’ faith is eroding in the ability to maintain defensive superiority over China, either through its own internal capabilities or the U.S.-Japan alliance. The consequence is that the evidence is now mounting of Japan shifting toward active “soft” and incipient “hard” balancing of China through a policy of the active “encirclement” of China diplomatically, the build-up of Japanese national military capabilities aimed to counter China’s access denial and power projection, and the strengthening of the U.S.-Japan alliance. This shift has become particularly evident following the 2010 trawler incident and the return to power of Prime Minister Abe Shinzō in 2012. The consequences of Japan’s shifting strategy are yet as not entirely clear. Japan may be moving toward a form of “Resentful Realism” that does not add to a new equilibrium to regional security but is actually more destabilizing and poses risk for China and the U.S., especially as Japan’s own security intentions become more opaque. In turn, these conclusions invite a reconsideration of the comfortable theoretical consensus on Japan as an eternal status quo power, and encourage Constructivism, Neoliberalism, but especially Neorealism, to be bolder in their assertions about the probability and degree of radicalism in Japan’s security trajectory.

This paper presents a cooperative strategy to achieve evenly spaced circular formation of a group of unmanned aerial vehicles. The strategy is claimed to be fail-safe because the circular formation remains unaltered even if one or more unmanned aerial vehicles fail. We can also add more unmanned aerial vehicles without altering the formation. The control law uses only bearing angle information. We can pre-specify the centre of the circular formation of the unmanned aerial vehicles. The unmanned aerial vehicles will maintain the desired distance from the centre with bearing angle measurement only. We assume that the unmanned aerial vehicles are identical and can measure the bearing angle of all the other unmanned aerial vehicles. The strategy is analysed using unicycle kinematic and verified using six-degree-of-freedom model of the unmanned aerial vehicles. Extensive simulations are carried out for noisy measurement, presence of wind and moving target.

We present a control framework for achieving encirclement of a target moving in 3D using a multi-robot system. Three variations of a basic control strategy are proposed for different versions of the encirclement problem, and their effectiveness is formally established. An extension ensuring maintenance of a safe inter-robot distance is also discussed. The proposed framework is fully decentralized and only requires local communication among robots; in particular, each robot locally estimates all the relevant global quantities. We validate the proposed strategy through simulations on kinematic point robots and quadrotor UAVs, as well as experiments on differential-drive wheeled mobile robots., Accepted for Autonomous Robots - Springer

Toponyms are proper geographic names of longer historic-geographic continuation. Local population inherits them by generation, remember them and inform both descendants and population of their spatial encirclement. In science toponyms denoting concrete geographic objects are recorded and written on maps with certain spatial borders representing thus a very stable element in studying geographic area. Changes of toponyms occur in longer time, i.e. civilization epochs, and very rarely in shorter time periods, these are usually the cases of sudden change of population or changes of political-historical circumstances of a territory. However, as linked to human conscience, toponyms often get different internal spatial meanings as well as different territorial belonging, where, in dependence on causes, they get narrower or overspread as in the case of Zlatibor toponyms. Total economic development of Zlatibor in the last more than a hundred years has caused this toponym spatially spread and got new forms. It appeared as oronym (name of relief object) and it has kept the same meaning up today, although in one period it was recorded as horonym (regional name) on maps. In the last decade it also appeared as oikonym (name of settlement)-Zlatibor, the name for ex settlement of Kraljeva Voda, later Partizanske Vode, joined with Palisad, but also as the name for wider spatial-administrative region-Zlatibor Region. At the same time, by spreading Zlatibor toponym, the toponyms of Cigota, Tornik and Murtenica are narrowed territorially, while with similar continuation of economic development it may be expected that Zlatibor toponym will overspread on the territory of Tara and Zlatar Mountains in the future, while these ones will reduce on names of their parts-peaks.

This paper develops the distributed encirclement control problem of multiagent systems, in which each agent tracks multiple targets, each target can be tracked by one agent, and the numbers of the agents and the targets are the same or not. Firstly, an encirclement control protocol is proposed for multiagent systems, and this protocol contains some estimators. Secondly, some conditions are derived, under which multiagent systems can achieve encirclement control by circular formation. Finally, numerical simulations are provided to illustrate the obtained results.

Cultural monuments mark historical past. They are included in anthropogenic tourist values. They present rare copies of creativity and they have exceptional artistic and esthetic values. The most numerous group are sacral objects. The largest attention deserve objects assigned in World cultural inheritance - monastery Studenica and monastery Sopocani with old town Ras. It is necessary to build caterer capacities, parking lots and sanitary devices in encirclement. Manifestations and presentations on domestic and foreign market contribute to cultural affirmation. Tourist valorization is impeded with that there are no evidence about number of visitors. In separating priorities we must consider uniqueness, rarity and fame. That?s the reason why Cele kula has tourist importance. Cultural monuments increase stay and serve as complementary tourist values. That?s why is necessary synthesis access in their learn and tourist presentation.

A triangular alliance was made among Pakistan, China and the United States to oppose the Soviet’s presence in Afghanistan. Common interest brought together these states to form a united front in 1980s and to help the anti-Soviet resistance forces in Afghanistan. The paper discusses and discovers the reasons of triangular joint front, their concerns and objectives. Pakistan was concerned about its western border with Afghanistan which was directly threatened. The eastern border was also not safe, as India had backing of the Moscow. Indian Ocean was another area under threat for which Kremlin had long been aspired to have access there. China was mainly concerned with its Muslim dominated Xinjiang region, having a common border with Wakhan area of Afghanistan. A direct threat was existing and could ignite the turbulent society of Xinjiang. Encirclement was an additional concern for China in the wake of Red Army’s climbing over Kabul. The US was fighting its ideological Cold War and used the Mujahideen against the Soviets. The paper analyzes that how the three states (Pakistan, China, US) strengthened their efforts against the Soviet and trained the Mujahideen. A descriptive-analytical and qualitative method is used for research. DOI: 10.5901/mjss.2014.v5n20p2192

The degree of cultural variation from one part of Lugbara to another is so great that there appears to be no fixed forms of ritual behaviour associated with sacrifice, nor many generally accepted views as to the aims of these behaviours. The Lugbara construct a great many shrines in and near their homesteads, at which offerings are made to the dead and to many kinds of spirits. Herein the problem of the relationship between forms of ritual offering, sickness, sin, and the continual restructuring of ordered social relations is addressed. Since living persons (save rainmakers or prophets) cannot directly contact Divine Spirit, they must request the dead to do so. There is a clear action of identification by a rite of encirclement of the sacrifier’s head or homestead or, in the case of a ceremony performed by a rainmaker, of the group’s territory. In all these rites, there is the consecration of an offering by means either of words or the laying on of hands. La variation culturelle à l’intérieur du pays lugbara est si grande qu’il ne semble y avoir ni de formes fixes de comportements rituels associés au sacrifice, ni d’avis communément partagés sur les finalités de tels comportements. Les Lugbara construisent beaucoup d’autels à l’intérieur et à proximité de leurs maisons où ils font des offrandes aux morts ou à plusieurs sortes d’esprits. Le problème adressé ici est celui du rapport entre les formes d’offrande rituelle, la maladie, le péché et le restructuration continuelle de l’ordre des liens sociaux. Comme les vivants (hormis faiseur de pluie ou prophète) ne peuvent pas entrer directement en contact avec Dieu, ils doivent se tourner vers les morts. On constate une rite d’identification qui s’accomplit par l’encerclement de la tête du sacrifiant ou de sa maison ou, dans le cas d’un rituel exécuté par un faiseur de pluie, par l’encerclement du territoire du groupe. Dans tous ces rites, il y une consécration d’une offrande par des mots ou par l’imposition des mains.

After 9/11 there is a general sense of the crisis of liberalism and secularism, and the need for greater security and surveillance. Diasporic Muslim communities have been increasingly the target of government interventions and investigations, resulting in various forms of governmentality that in fact constitute a ‘management of Muslims.’ The traditional strategies of benign neglect have been replaced by periods of intense governmental activity. The idea of ‘managing Muslims’ is often disguised by a more neutral terminology such as pluralism or multiculturalism. This article examines two versions of the management of religions from policies of ‘upgrading’ or retraining of Muslims for modernity to more robust policies of containment, rendition and seclusion. The result of securitisation and globalisation is the rise of a new type of society that I call ‘the enclave society.’ In such societies governments are creating new policies of ‘enclavement’ to quarantine communities that are undesirable or unwanted or dangerous. The mobility of a global society is now being constrained by encirclement and enclavement through building walls, ghettoes, catchments and no-go areas. Such policies are likely to be counter productive, requiring an escalation of draconian interventions.