Testing the expectations model of the term structure: some conjectures on the effects of institutional changes

Interest rates ; Rational expectations (Economic theory)

DARIS, a fleet of passive formation flying small satellites for low frequency radio astronomy

DARIS (Distributed Aperture Array for Radio Astronomy In Space) is a mission to conduct radio astronomy in the low frequency region from 1-10MHz. This region has not yet been explored, as the Earth's ionosphere is opaque to those frequencies, and so a space based observatory is the only solution. DARIS will undertake an extragalactic survey of the low frequency sky, and can also detect some transient radio events such as solar or planetary bursts. To achieve these scientific objectives, DARIS comprises a space-based array, forming a very large effective aperture, as required for such a long wavelength survey. Each station in the array (each required to be a small satellite to ensure several nodes can be flown) carries three orthogonal dipole antennas, each 5m in length. The more station nodes in the array, the more sensitive the antenna. The entire fleet remains within a 100km diameter cloud. \ud A very large data volume is generated by each node, as the antennas have to capture all radio signals, after which the data can be correlated to find the astronomical signal in the noise. As the astronomical signals also have a noise-like nature, no compression is possible on the data captured by the nodes. The data volume is too high to transfer directly to Earth, and will need to be correlated in space. Distributed correlation between the nodes is technically challenging, and therefore a mothership acts as the central correlator and then downlinks the correlated data (lower volume) to Earth. \u

An analytical comparison of the patient-to-doctor policy and the doctor-to-patient policy in the outpatient clinic

Outpatient clinics traditionally organize processes such that the doctor remains in a consultation room, while patients visit for consultation, we call this the Patient-to-Doctor policy. A different approach is the Doctor-to-Patient policy, whereby the doctor travels between multiple consultation rooms, in which patients prepare for their consultation. In the latter approach, the doctor saves time by consulting fully prepared patients. We compare the two policies via a queueing theoretic and a discrete-event simulation approach. We analytically show that the Doctor-to-Patient policy is superior to the Patient-to-Doctor policy under the condition that the doctor’s travel time between rooms is lower than the patient’s preparation time. Simulation results indicate that the same applies when the average travel time is lower than the average preparation time. In addition, to calculate the required number of consultation rooms in the Doctor-to-Patient policy, we provide an expression for the fraction of consultations that are in immediate succession; or, in other words, the fraction of time the next patient is prepared and ready, immediately after a doctor finishes a consultation.We apply our methods for a range of distributions and parameters and to a case study in a medium-sized general hospital that inspired this research

CFD Modelling coupled with Floating Structures and Mooring Dynamics for Offshore Renewable Energy Devices using the Proteus Simulation Toolkit

This is the author accepted manuscript. The final version is available from EWTEC via the link in this record.In this work, the coupling of novel opensource tools for simulating two-phase incompressible flow problems with fluid-structure interaction and mooring dynamics is presented. The open-source Computational Fluid Dynamics (CFD) toolkit Proteus is used for the simulations. Proteus solves the twophase Navier-Stokes equations using the Finite Element Method (FEM) and is fully coupled with an Arbitrary Lagrangian-Eulerian (ALE) formulation for mesh motion allowing solid body motion within the fluid domain. The multi-body dynamics solver, Chrono, is used for calculating rigid body motion and modelling dynamics of complex mooring systems. At each time step, Proteus computes the forces from the fluid acting on the rigid body necessary to find its displacement with Chrono which will be used as boundary conditions for mesh motion. Several verification and validation cases are presented here in order to prove the successful coupling between the two toolkits aforementioned. These test cases include wave sloshing in a tank, floating body dynamics under free and wave-induced motion for different degrees of freedom (DOFs), and mooring dynamics using beam element theory coupled with rigid body dynamics and collision detection. The successful validation of each component shows the potential of the coupled methodology to be used for assisting the design of offshore renewable energy devices.Support for this work was given by the Engineer Research and Development Center (ERDC) and HR Wallingford through the collaboration agreement (Contract No. W911NF-15-2-0110). The authors also acknowledge support for the IDCORE program from the Energy Technologies Institute and the Research Councils Energy Programme (grant number EP/J500847/)

Intrinsic Continuous Process Safeguarding Revisited for Batch Reactions

Intrinsic continuous process safeguarding (ICPS) is a methodology to substantially improve the process safety of chemical reactions. It was proposed in 1985. The origin of the method is explained in Control of a Potential Undesired Reaction. Two serious events that occurred with chemical reactors between 2000 and 2020 were selected from the databases of the Chemical Safety and Hazard Investigation Board (USA) and the European Major Accident Reporting System (eMARS). The occurrence of these events could have been prevented or their effects could have been mitigated if the principles of ICPS had been applied.</p

Epistasis between 5-HTTLPR and ADRA2B polymorphisms influences attentional bias for emotional information in healthy volunteers

Individual differences in emotional processing are likely to contribute to vulnerability and resilience to emotional disorders such as depression and anxiety. Genetic variation is known to contribute to these differences but they remain incompletely understood. The serotonin transporter (5-HTTLPR) and alpha(2B)-adrenergic autoreceptor (ADRA2B) insertion/deletion polymorphisms impact on two separate but interacting monaminergic signalling mechanisms that have been implicated in both emotional processing and emotional disorders. Recent studies suggest that the 5-HTTLPR s allele is associated with a negative attentional bias and an increased risk of emotional disorders. However, such complex behavioural traits are likely to exhibit polygenicity, including epistasis. This study examined the contribution of the 5-HTTLPR and ADRA2B insertion/deletion polymorphisms to attentional biases for aversive information in 94 healthy male volunteers and found evidence of a significant epistatic effect (p < 0.001). Specifically, in the presence of the 5-HTTLPR s allele, the attentional bias for aversive information was attenuated by possession of the ADRA2B deletion variant whereas in the absence of the s allele, the bias was enhanced. These data identify a cognitive mechanism linking genotype-dependent serotonergic and noradrenergic signalling that is likely to have implications for the development of cognitive markers for depression/anxiety as well as therapeutic drug effects and personalized approaches to treatment

Report on the evaluation of the IMD programme in Guatemala 2002 - 2003

An external evaluation was carried out in July-August 2003 to assess the results and the implementation process of the first 15 months of IMD’s programme in Guatemala. The central objective of this programme is to strengthen political parties and the party system in a sustainable way. Several unfavourable conditions limit the realisation of this ambition: (i) the political party system in Guatemala has been unstable, fragmented, polarised and discredited, (ii) political parties were often not more than electoral machines, lacking a programmatic and ideological base, and generally figured among the weakest actors in society, (iii) political participation by citizens has been very low, especially among the indigenous majority of the population. Against this background, since March 2002 IMD developed in a joint venture with UNDP an ambitious project for a multiparty dialogue process, trying to generate consensus on a shared National Agenda that reflects the basic principles of the Peace Agreements. The basic idea was that collaboration and dialogue among the parties is a prerequisite for future democratic stability, as none of the individual parties is able to sustain such a national project. Moreover, the national Congress does not function as a forum for dialogue given the polarized political climate in the country...

Design and Control of Warehouse Order Picking: a literature review

Order picking has long been identified as the most labour-intensive and costly activity for almost every warehouse; the cost of order picking is estimated to be as much as 55% of the total warehouse operating expense. Any underperformance in order picking can lead to unsatisfactory service and high operational cost for its warehouse, and consequently for the whole supply chain. In order to operate efficiently, the orderpicking process needs to be robustly designed and optimally controlled. This paper gives a literature overview on typical decision problems in design and control of manual order-picking processes. We focus on optimal (internal) layout design, storage assignment methods, routing methods, order batching and zoning. The research in this area has grown rapidly recently. Still, combinations of the above areas have hardly been explored. Order-picking system developments in practice lead to promising new research directions

2D Coupled CFD model of and Oscillating Water Column using PROTEUS

This is the author accepted manuscript. The final version is available from ASRANet via the link in this recordFloating Oscillating Water Columns (OWC) are one of many potential Renewable Energy Devices under consideration as part of the global drive towards clean energy sources. In order to reach deployment, these devices first exist in the form of computational models. These models allow the devices to be tested under a range of conditions and mooring configurations. However, the design of systems often fails to account for the moorings at an early stage, which can result in disappointing performance at later stages of design and deployment. In this study, Proteus is used to produce a 2D model of an OWC that demonstrates its effectiveness as a tool for modelling floating marine structures. The model solves the Reynolds Averaged Navier Stokes equations in the fluid domain, using a Volume of Fluid-Level Set approach for defining the air-water interface. Proteus is coupled with the Chrono library to solve the rigid body motions, and the response of the mooring lines. The model is validated against both experimental and other computational models. The effect of a mooring system is shown on the water column response. This study provides a launch pad for more complex studies. Proteus has 3D modelling capabilities, and as a result, 3D OWC, other wave energy devices and floating wind turbines are all potential devices that Proteus has the capability to recreate in high fidelity models.ERDCHR WallingfordEnergy Technologies Institute (ETI)Engineering and Physical Sciences Research Council (EPSRC