Shepherd's Dilemma

Recent outbreaks of Rift Valley Fever in sheep have led to boycotts of African livestock by Middle Eastern importers. To normalize trade, attempts have been made to apply new livestock forecasting and monitoring technologies. In this process, producers have exhibited a resistance in revealing livestock health information, a resistance that could jeopardize the information system and lead to further boycotts. We investigate the incentives governing this problem and model the most fundamental contract issues, those concerning reputation and credibility. Equilibrium contracts require that the buyer compensate the producer for private information to address the shepherd's dilemma of concealing livestock information (and facing continued boycotts) or revealing the information and being blacklisted.Livestock Production/Industries,

An evaluation of students' and lecturers' use of technologies: an engineering case study.

yesThe introduction in the early 1990s of the world wide web was a significant factor in the creation of a global information society, allowing new possibilities to work, entertain and communicate, from home, at the workplace or on the move. In recent years, there have been significant advances in information technology (IT), while a new generation of applications that are able to harness the power of the world wide web has been introduced under the banner of Web 2.0. The increased capabilities of IT and the nature of Web 2.0 applications have attracted interest from the academic community as a means of enhancing the delivery of higher education. This paper considers the implications of introducing technology into the higher education sector from the perspectives of academic staff and students, with particular emphasis on the use of technology and Web 2.0 applications, and the relationship between technology and teaching and learning

Guest Editorial: Satellite Systems, Applications and Networking.

yesGuest Editorial of Special Issue (featuring eight original papers, comprising 133 pages in total). Whilst satellite systems continue to be at the forefront of broadcast communication service provision, they have an increasingly important role to play in the provision of global Internet services. There has been a strong trend towards convergence of communication services in recent times, with the Internet providing the ideal platform on which to base such convergence. Even traditional circuit-switched applications (such as voice and video streaming) have been shown to work effectively over the Internet. Although the Internet is prevalent in the developed world, satellites are vital to extending this into more remote and sparsely populated regions of the world. It is therefore important that satellite technology is advanced to provide seamless interoperability with the Internet and adequate Quality of Service (QoS) support. The purpose of this special issue is to present research devoted to furthering satellite technology and networking to support the provision of both current and future applications

Ubiquitous Internet in an integrated satellite-terrestrial environment: The SUITED solution

yesThe current Internet architecture appears to not be particularly suited to addressing the emerging needs of new classes of users who wish to gain access to multimedia services made available by ISPs, regardless of their location, while in motion and with a guaranteed level of quality. One of the main objectives of so-called nextgeneration systems is to overcome the limitations of today¿s available Internet by adopting an approach based on the integration of different mobile and fixed networks. The SUITED project moves in this direction since it aims at contributing to the design and deployment of the global mobile broadband system (GMBS), a unique satellite/terrestrial infrastructure ensuring nomadic users access to Internet services with a negotiated QoS. A description of the main features of the GMBS architecture, characterized by the integration of a multisegment access network with a federated ISP network is given in this article. The GMBS multimode terminal is schematically described, and an overview of the so-called QoS-aware mobility management scheme, devised for such a heterogeneous scenario,is provided

Selective oxidative degradation of azo dyes by hydrogen peroxide catalysed by manganese(II) ions

Manganese(II) ions catalyse the oxidative degradation of Calmagite (H3CAL) dye in aqueous solution at 20 ± 1 °C in the pH range 7.5–9.0 using hydrogen peroxide (H2O2) as oxidant by a mechanism that involves strong complexation to the MnII centre. It is proposed that [MnIII(CAL)(O2H)]− i.e. a dye coordinated hydroperoxyl (O2H−) MnIII complex is formed and bleaching of the dye is initiated by an electron-transfer to MnIII, with the binding of H2O2 being the rate determining step. At pH 9.0 in (bi)carbonate, HCO3−, H3CAL is rapidly bleached via the in situ formation of coordinated peroxycarbonate (HCO4−); a TOF (TOF = moles of dye bleached per mole of manganese per hour) of ∼5000 h−1 can be achieved. The bleaching of the related azo dyes Orange II and Orange G is different because, unlike Calmagite, they lack an o,o-dihydroxy motif so are unable to complex strongly to MnII and no oxidation to MnIII occurs. At pH 8.0 (phosphate buffer) Orange II and Orange G are not bleached but bleaching can be achieved at pH 9.0 (HCO3− buffer); the rate determining step is dye coordination and it is proposed bleaching is achieved via an outer-sphere oxygen atom transfer. Mechanisms for dye bleaching at pH 8.0 and pH 9.0 are proposed using data from EPR, UV/VIS and ESI-MS. MnII/H2O2/HCO3− form a potent oxidising mixture that is capable of removing stubborn stains such as curcumin

Performance Analysis of Satellite Payload Architectures for Mobile Services

YesThis paper is concerned with the effects on the network performance of moving parts of what is considered traditionally to belong to the ground segment to on board the satellite. Initially, an overview of geostationary satellite communication systems and payload technology is presented, followed by a description of the network architecture and protocols that are the basis of the simulation models. The results obtained from this testbed are presented before concluding with a discussion of the results obtained