Capillary trees for passive pumping water

Capillary flows are an attractive feature for passive water harvesting as they require no external driving force to pull the fluid out within the capillary network. Here we analyze the architecture of capillary flow networks in steady state, and the impact of the network morphology on the maximum mass flow rate that can be extracted for a fixed network volume and fixed network footprint. We develop a search algorithm to test the possible location of all the junction and bifurcation nodes and the changes in diameter ratios with the objective of obtaining the maximum mass flow rate from the network. We define the Capillary Strength CS as a local indicator to determine the geometrical parameters of each conduct that allow to sustain the overall mass flow rate. It is shown that the diameter ratio of connected tubes for maximum mass flow rate depends on the distance from the network outlet, and therefore does not follow the Hess-Murray’s law. The superiority of dendritic architectures in the roots and canopy branches of the capillary trees is demonstrated.

Quantum linear network coding for entanglement distribution in restricted architectures

In this paper we propose a technique for distributing entanglement in architectures in which interactions between pairs of qubits are constrained to a fixed network G. This allows for two-qubit operations to be performed between qubits which are remote from each other in G, through gate teleportation. We demonstrate how adapting quantum linear network coding to this problem of entanglement distribution in a network of qubits can be used to solve the problem of distributing Bell states and GHZ states in parallel, when bottlenecks in G would otherwise force such entangled states to be distributed sequentially. In particular, we show that by reduction to classical network coding protocols for the k-pairs problem or multiple multicast problem in a fixed network G, one can distribute entanglement between the transmitters and receivers with a Clifford circuit whose quantum depth is some (typically small and easily computed) constant, which does not depend on the size of G, however remote the transmitters and receivers are, or the number of transmitters and receivers. These results also generalise straightforwardly to qudits of any prime dimension. We demonstrate our results using a specialised formalism, distinct from and more efficient than the stabiliser formalism, which is likely to be helpful to reason about and prototype such quantum linear network coding circuits.

Altruism and Risk Sharing in Networks

We provide the first analysis of the risk-sharing implications of altruism networks. Agents are embedded in a fixed network and care about each other. We explore whether altruistic transfers help smooth consumption and how this depends on the shape of the network. We find that altruism networks have a first-order impact on risk. Altruistic transfers generate efficient insurance when the network of perfect altruistic ties is strongly connected. We uncover two specific empirical implications of altruism networks. First, bridges can generate good overall risk sharing, and, more generally, the quality of informal insurance depends on the average path length of the network. Second, large shocks are well-insured by connected altruism networks. By contrast, large shocks tend to be badly insured in models of informal insurance with frictions. We characterize what happens for shocks that leave the structure of giving relationships unchanged. We further explore the relationship between consumption variance and centrality, correlation in consumption streams across agents, and the impact of adding links.

Developing TAMEx Model For Availability Aspect of E-Exam Security in WLAN Environment

The internet has provided tremendous impact in educational development throughout the world. E-Exam system is one of educational component which has been used increasing dramatically for evaluating educational process. As an e-exam feature, uniformity of system access and time duration of the exam to all examinees is very important to be considered. Exam manager usually utilizes a fixed network to connect all e-exam terminal in order to maintain service stability on e-exam systems. However, the use of a fixed network will be difficult to be implemented if the number of examines is large. There are not many Education institutions have adequate ICT infrastructure or e-exam terminals for all students. Most institutions develop WLAN networks as an alternative to being able to provide ICT services to all students. With the development of mobile device technology (Handphone or Laptop) that strongly supports the learning process through mobile devices. This research aims to develop application of the Time Adaptive for Mobile E-Exam (TAMEx) Model. It serves to maintain the reliability of e-exam implementation on WLAN networks. The possible connection disruptions is anticipate by seeking time compensation only to participants who has experienced the connection problem. The time compensation must be accordance to the duration of the occurrence of connection loss. Application development has been carried out and is functioning properly. The report of application shows that it has succeeded in identifying the connection disturbance duration and provide time compensation to the proper examinee.

Network simulations of optical illusions

We examine a dynamical network model of visual processing that reproduces several aspects of a well-known optical illusion, including subtle dependencies on curvature and scale. The model uses a genetic algorithm to construct the percept of an image, and we show that this percept evolves dynamically so as to produce the illusions reported. We find that the perceived illusions are hardwired into the model architecture and we propose that this approach may serve as an archetype to distinguish behaviors that are due to nature (i.e. a fixed network architecture) from those subject to nurture (that can be plastically altered through learning).