A gust-attenuation controller for fixed-wing UAVs during collision avoidance course

This paper presents a nonlinear gust-attenuation controller to stabilize velocities, attitudes and angular rates of a fixed-wing unmanned aerial vehicle (UAV) in the presence of wind gusts. The proposed controller aims to achieve a steady-state flight condition such that the host UAV can avoid airspace collision with other UAVs during the cruise flight. Based on the typical UAV model capturing flight aerodynamics, a nonlinear Hinf controller is developed with rapid response property in consideration of actuator constraints. Simulations are conducted for the Shadow UAV to verify performance of the proposed controller. Comparative studies with the proportional-integral derivative (PID) controllers demonstrate that the proposed controller exhibits great performance improvement in a gusty environment, making it suitable for integration into the design of flight control systems for cruise flight with safety guarantees.

A boundary preserving numerical algorithm for the Wright-Fisher model with mutation

The Wright-Fisher model is an Itô stochastic differential equation that was originally introduced to model genetic drift within finite populations and has recently been used as an approximation to ion channel dynamics within cardiac and neuronal cells. While analytic solutions to this equation remain within the interval [0,1], current numerical methods are unable to preserve such boundaries in the approximation. We present a new numerical method that guarantees approximations to a form of Wright-Fisher model, which includes mutation, remain within [0,1] for all time with probability one. Strong convergence of the method is proved and numerical experiments suggest that this new scheme converges with strong order 1/2. Extending this method to a multidimensional case, numerical tests suggest that the algorithm still converges strongly with order 1/2. Finally, numerical solutions obtained using this new method are compared to those obtained using the Euler-Maruyama method where the Wiener increment is resampled to ensure solutions remain within [0,1].

Nangkha Nangdrik in the land of the thunder dragon

- The Kingdom of Bhutan is a country on the move - In July 2008, Bhutan transitioned from an absolute monarchy to a constitutional monarchy - The Constitution and a number of pieces of national legislation make specific reference to alternative dispute resolution. - An alternative dispute resolution Bill will come before the Bhutanese parliament in early 2012.

Legal Institutions and Collective Memories

In recent decades the debate among scholars, lawyers, politicians and others about how societies deal with their past has been constant and intensive. 'Legal Institutions and Collective Memories' situates the processes of transitional justice at the intersection between legal procedures and the production of collective and shared meanings of the past. Building upon the work of Maurice Halbwachs, this collection of essays emphasises the extended role and active involvement of contemporary law and legal institutions in public discourse about the past, and explores their impact on the shape that collective memories take in the course of time. The authors uncover a complex pattern of searching for truth, negotiating the past and cultivating the art of forgetting. Their contributions explore the ambiguous and intricate links between the production of justice, truth and memory. The essays cover a broad range of legal institutions, countries and topics. These include transitional trials as 'monumental spectacles' as well as constitutional courts, and the restitution of property rights in Central and Eastern Europe and Australia. The authors explore the biographies of victims and how their voices were repressed, as in the case of Korean Comfort Women. They explore the role of law and legal institutions in linking individual and collective memories in the transitional period through processes of lustration, and they analyse divided memories about the past and their impact on future reconciliation in South Africa. The collection offers a genuinely comparative approach, allied to cutting-edge theory.

Forward-secure hierarchical predicate encryption

Secrecy of decryption keys is an important pre-requisite for security of any encryption scheme and compromised private keys must be immediately replaced. \emph{Forward Security (FS)}, introduced to Public Key Encryption (PKE) by Canetti, Halevi, and Katz (Eurocrypt 2003), reduces damage from compromised keys by guaranteeing confidentiality of messages that were encrypted prior to the compromise event. The FS property was also shown to be achievable in (Hierarchical) Identity-Based Encryption (HIBE) by Yao, Fazio, Dodis, and Lysyanskaya (ACM CCS 2004). Yet, for emerging encryption techniques, offering flexible access control to encrypted data, by means of functional relationships between ciphertexts and decryption keys, FS protection was not known to exist.\smallskip In this paper we introduce FS to the powerful setting of \emph{Hierarchical Predicate Encryption (HPE)}, proposed by Okamoto and Takashima (Asiacrypt 2009). Anticipated applications of FS-HPE schemes can be found in searchable encryption and in fully private communication. Considering the dependencies amongst the concepts, our FS-HPE scheme implies forward-secure flavors of Predicate Encryption and (Hierarchical) Attribute-Based Encryption.\smallskip Our FS-HPE scheme guarantees forward security for plaintexts and for attributes that are hidden in HPE ciphertexts. It further allows delegation of decrypting abilities at any point in time, independent of FS time evolution. It realizes zero-inner-product predicates and is proven adaptively secure under standard assumptions. As the ``cross-product" approach taken in FS-HIBE is not directly applicable to the HPE setting, our construction resorts to techniques that are specific to existing HPE schemes and extends them with what can be seen as a reminiscent of binary tree encryption from FS-PKE.

Nonlinear H_infinity control of UAVs for collision avoidance in gusty environments

This paper proposes a nonlinear H_infinity controller for stabilization of velocities, attitudes and angular rates of a fixed-wing unmanned aerial vehicle (UAV) in a windy environment. The suggested controller aims to achieve a steady-state flight condition in the presence of wind gusts such that the host UAV can be maneuvered to avoid collision with other UAVs during cruise flight with safety guarantees. This paper begins with building a proper model capturing flight aerodynamics of UAVs. Then a nonlinear controller is developed with gust attenuation and rapid response properties. Simulations are conducted for the Shadow UAV to verify performance of the proposed con- troller. Comparative studies with the proportional-integral-derivative (PID) controllers demonstrate that the proposed controller exhibits great performance improvement in a gusty environment, making it suitable for integration into the design of flight control systems for cruise flight of UAVs.

The Australian Consumer Law

Reform of Australia’s inconsistent Commonwealth, State and Territory consumer laws is now a reality. The 1 January 2011 commencement of the Australian Consumer Law (ACL), within the Competition and Consumer Act 2010, is the culmination of a long process of consultation. Unifying and rationalising the plethora of laws, this new Act sees the disappearance of the “Trade Practices Act” and the amendment of a raft of State and Territory legislation; the new national regime informed by them operates in their stead. This is indisputably the most comprehensive change in the history of the Trade Practices Act 1974. This book aims to assist practitioners, academics and students understand the Australian Consumer Law regime and its impact. It summarises the history and constitutional basis of the ACL, explaining how the ACL will be implemented, amended and enforced. In addition it explores how the various general and specific protections interrelate, and the scope of their overlap, and considers the content of the ACL, and the principal changes from the provisions of the Trade Practices Act.

Adverse possession and Crown Leasehold in Queensland

The decision of Eckford v Stanbroke Pastoral Co Pty Ltd [2012] QSC 48 ,although a decision refusing summary judgement raises a very important question of the ability to claim adverse possession of a pastoral lease issued in 1956 under the Land Act 1962 (Queensland).Division 5 of Part 6 of the Land Title Act 1994 (Qld) which guarantees registered freehold title expressly deals with the right of adverse possession however, there is no such provision in the present Land Act 1994 unlike s 170 of the Crown Lands Act 1989(NSW) which expressly precludes claims for adverse possession of specified non freehold land. There is no mention of adverse possession in any version of the Queensland Land Acts and only s 6(4) of the Limitation of Actions Act 1974 makes it clear that “the right, title or interest of the Crown” in or to any land is not affected by any adverse possessor.It is against the background that the Court considered the right of an adverse possessor to a Crown lease.

A hybrid smoothed finite element method (H-SFEM) to solid mechanics problems

In this paper, a hybrid smoothed finite element method (H-SFEM) is developed for solid mechanics problems by combining techniques of finite element method (FEM) and Node-based smoothed finite element method (NS-FEM) using a triangular mesh. A parameter is equipped into H-SFEM, and the strain field is further assumed to be the weighted average between compatible stains from FEM and smoothed strains from NS-FEM. We prove theoretically that the strain energy obtained from the H-SFEM solution lies in between those from the compatible FEM solution and the NS-FEM solution, which guarantees the convergence of H-SFEM. Intensive numerical studies are conducted to verify these theoretical results and show that (1) the upper and lower bound solutions can always be obtained by adjusting ; (2) there exists a preferable at which the H-SFEM can produce the ultrasonic accurate solution.

On the impact of the "linguistic turn" on research in information systems

The linguistic turn within philosophy has recently gained increased attention within social sciences. It can be seen as an attempt to investigate traditional philosophical problems by analysing the linguistic expressions used for these investigations. More generally, the phenomenon of language itself must be considered because of its (constitutional) impact on the investigation of phenomena in social sciences. In order to understand the consequences of the linguistic turn, its origins in philosophy are important and will be discussed. Within social sciences the linguistic turn already had significant impact. As an example, we will therefore discuss what directions the linguistic turn enabled for organizational analysis. Information Systems as a discipline must face the consequences of the linguistic turn as well. We will discuss how the linguistic framework introduced impacts the development of knowledge management and that of managerial and organizational support systems. This example shows what different perspectives the linguistic turn can provide for investigations within Information Systems. In addition, we will briefly outline the impact of the linguistic turn with respect to methodologies in Information Systems research.

Bailing out the FEG : is the Fair Entitlements Guarantee (formerly GEERS) approaching its own fiscal cliff?

This article discusses what recent statistics and public reports reveal about the funding of GEERS (now the FEG) and its bottom line. The article examines (1) whether there has been a “blowout” in the scheme which guarantees the recovery of employee entitlements in liquidations and (2) what might be done to put the scheme on a firmer fiscal footing.

Judicial intervention in the affairs of unincorporated religious associations in New South Wales

The leading Australian High Court case of Cameron v Hogan (1934) 51 CLR 358 confirmed that associations which are 'social, sporting, political, scientific, religious, artistic or humanitarian in character’, and not formed ‘for private gain or material advantage’, are usually formed on a basis of mutual consent. Unless there is some clear, positive indication that the members wish to relate to each other in a legal fashion, the rules of the association will not be treated as an enforceable contract in contrast to the rules of incorporated bodies. Australian unincorporated associations experiencing internal disputes, like those in most other common law jurisdictions, have found courts reluctant to provide a remedy unless there is a proprietary interest or trust to protect. This is further compounded by the judicial view that an unincorporated association has no legal recognition as a ‘juristic person’. The right to hold property and the ability to sue and be sued are incidences of this recognition. By contrast, the law recognises ‘artificial’ legal persons such as corporations, who are given rights to hold property and to sue and be sued. However, when a number of individuals associate together for a non-commercial, lawful purpose, but not by way of a corporate structure, legal recognition ‘as a group’ is denied. Since 1934, a significant number of cases have distinguished or otherwise declined to follow this precedent of the High Court. A trenchant criticism is found in McKinnon v Grogan [1974] 1 NSWLR 295, 298 where Wootten J said that ‘citizens are entitled to look to the courts for the same assistance in resolving disputes about the conduct of sporting, political and social organisations as they can expect in relation to commercial institutions’. According to Wootten J at 298, if disputes are not settled by the courts, this would create a ‘legal-no-man's land, in which disputes are settled not in accordance with justice and the fulfilment of deliberately undertaken obligations, but by deceit, craftiness, and an arrogant disregard of rights’. Cameron v Hogan was decided in 1934. There is an increasing volume of first instance cases which distinguish or, in the words of Palmer J, ‘just pay lip service’ to this High Court decision. (Coleman v Liberal Party of Australia (2007) 212 FLR 271, 278). The dissenting cases seem to call for a judicial policy initiative. This would require recognition by judges that voluntary associations play a significant role in society and that members have a legitimate, enforceable expectation that the rules of the association will be observed by members and in the last resort, enforced by the courts without the need to prove contractual intention, the existence of a trust or the existence of a right of a proprietary nature. This thesis asks: what legal, as distinct from political, redress does an ordinary member have, when a rule is made or a process followed which is contrary to the underlying doctrines and philosophies embodied in the constitutional documents of an unincorporated religious association? When, if at all, will a court intervene to ensure doctrinal purity or to supervise the daily life of a large unincorporated religious association? My research objective is to examine and analyse leading cases and relevant legislation on the enforceability of the constitutions of large, unincorporated, religious associations with particular reference to the Anglican Church in New South Wales. Given its numerical size, wide geographical spread and presence since the foundation of New South Wales, the Anglican Church in New South Wales, contains a sufficient variety of ‘real life’ situations to be representative of the legal issues posed by Cameron v Hogan which may be faced by other large, unincorporated, religious associations in New South Wales. In contemporary society, large, unincorporated, religious associations play an important community role. The resolution of internal disputes in such associations should not remain captive to legal doctrines of an earlier age.

Predicate encryption with various properties

Predicate encryption (PE) is a new primitive which supports exible control over access to encrypted data. In PE schemes, users' decryption keys are associated with predicates f and ciphertexts encode attributes a that are specified during the encryption procedure. A user can successfully decrypt if and only if f(a) = 1. In this thesis, we will investigate several properties that are crucial to PE. We focus on expressiveness of PE, Revocable PE and Hierarchical PE (HPE) with forward security. For all proposed systems, we provide a security model and analysis using the widely accepted computational complexity approach. Our first contribution is to explore the expressiveness of PE. Existing PE supports a wide class of predicates such as conjunctions of equality, comparison and subset queries, disjunctions of equality queries, and more generally, arbitrary combinations of conjunctive and disjunctive equality queries. We advance PE to evaluate more expressive predicates, e.g., disjunctive comparison or disjunctive subset queries. Such expressiveness is achieved at the cost of computational and space overhead. To improve the performance, we appropriately revise the PE to reduce the computational and space cost. Furthermore, we propose a heuristic method to reduce disjunctions in the predicates. Our schemes are proved in the standard model. We then introduce the concept of Revocable Predicate Encryption (RPE), which extends the previous PE setting with revocation support: private keys can be used to decrypt an RPE ciphertext only if they match the decryption policy (defined via attributes encoded into the ciphertext and predicates associated with private keys) and were not revoked by the time the ciphertext was created. We propose two RPE schemes. Our first scheme, termed Attribute- Hiding RPE (AH-RPE), offers attribute-hiding, which is the standard PE property. Our second scheme, termed Full-Hiding RPE (FH-RPE), offers even stronger privacy guarantees, i.e., apart from possessing the Attribute-Hiding property, the scheme also ensures that no information about revoked users is leaked from a given ciphertext. The proposed schemes are also proved to be secure under well established assumptions in the standard model. Secrecy of decryption keys is an important pre-requisite for security of (H)PE and compromised private keys must be immediately replaced. The notion of Forward Security (FS) reduces damage from compromised keys by guaranteeing confidentiality of messages that were encrypted prior to the compromise event. We present the first Forward-Secure Hierarchical Predicate Encryption (FS-HPE) that is proved secure in the standard model. Our FS-HPE scheme offers some desirable properties: time-independent delegation of predicates (to support dynamic behavior for delegation of decrypting rights to new users), local update for users' private keys (i.e., no master authority needs to be contacted), forward security, and the scheme's encryption process does not require knowledge of predicates at any level including when those predicates join the hierarchy.

Recognition and enforcement of foreign judgments : are the rules appropriate?

The recognition and enforcement of foreign judgments is an aspect of private international law, and concerns situations where a successful party to litigation seeks to rely on a judgment obtained in one court, in a court in another jurisdiction. The most common example where the recognition and enforcement of foreign judgments may arise is where a party who has obtained a favourable judgment in one state or country may seek to recognise and enforce the judgment in another state or country. This occurs because there is no sufficient asset in the state or country where the judgment was rendered to satisfy that judgment. As technological advancements in communications over vast geographical distances have improved exponentially in recent years, there has been an increase in cross-border transactions, as well as litigation arising from these transactions. As a result, the recognition and enforcement of foreign judgments is of increasing importance, since a party who has obtained a judgment in cross-border litigation may wish to recognise and enforce the judgment in another state or country, where the defendant’s assets may be located without having to re-litigate substantive issues that have already been resolved in another court. The purpose of the study is to examine whether the current state of laws for the recognition and enforcement of foreign judgments in Australia, the United States and the European Community are in line with modern-commercial needs. The study is conducted by weighing two competing objectives between the notion of finality of litigation, which encourages courts to recognise and enforce judgments foreign to them, on the one hand, and the adequacy of protection to safeguard the recognition and enforcement proceedings, so that there would be no injustice or unfairness if a foreign judgment is recognised and enforced, on the other. The findings of the study are as follows. In both Australia and the United States, there is a different approach concerning the recognition and enforcement of judgments rendered by courts interstate or in a foreign country. In order to maintain a single and integrated nation, there are constitutional and legislative requirements authorising courts to give conclusive effects to interstate judgments. In contrast, if the recognition and enforcement actions involve judgments rendered by a foreign country’s court, an Australian or a United States court will not recognise and enforce the foreign judgment unless the judgment has satisfied a number of requirements and does not fall under any of the exceptions to justify its non-recognition and non-enforcement. In the European Community, the Brussels I Regulation which governs the recognition and enforcement of judgments among European Union Member States has created a scheme, whereby there is only a minimal requirement that needs to be satisfied for the purposes of recognition and enforcement. Moreover, a judgment that is rendered by a Member State and based on any of the jurisdictional bases set forth in the Brussels I Regulation is entitled to be recognised and enforced in another Member State without further review of its underlying jurisdictional basis. However, there are concerns as to the adequacy of protection available under the Brussels I Regulation to safeguard the judgment-enforcing Member States, as well as those against whom recognition or enforcement is sought. This dissertation concludes by making two recommendations aimed at improving the means by which foreign judgments are recognised and enforced in the selected jurisdictions. The first is for the law in both Australia and the United States to undergo reform, including: adopting the real and substantial connection test as the new jurisdictional basis for the purposes of recognition and enforcement; liberalising the existing defences to safeguard the application of the real and substantial connection test; extending the application of the Foreign Judgments Act 1991 (Cth) in Australia to include at least its important trading partners; and implementing a federal statutory scheme in the United States to govern the recognition and enforcement of foreign judgments. The second recommendation is to introduce a convention on jurisdiction and the recognition and enforcement of foreign judgments. The convention will be a convention double, which provides uniform standards for the rules of jurisdiction a court in a contracting state must exercise when rendering a judgment and a set of provisions for the recognition and enforcement of resulting judgments.