Routing Path Assignment for Joint Load Balancing and Fast Failure Recovery in IP Network

Distributed link-state routing protocols, including Open Shortest Path First (OSPF) and Intermediate System–Intermediate System (IS-IS), have successfully provided robust shortest path routing for IP networks. However, shortest path routing is inflexible and sometimes results in congestion on some critical links. By separating the control plane and the data plane, the centralized control of Software Defined Networking (SDN)-based approach possesses flexible routing capabilities. Fibbing is an approach that can achieve centralized control over a network running distributed routing protocols. In a Fibbing-controlled IP network, the controller cleverly generates fake protocol messages to manipulate routers to steer the flow of the desired paths. However, introducing fake nodes destroys the structure of the loop-free property of Loop-Free Alternate (LFA) that is used to achieve fast failure recovery in IP networks. This paper addresses this issue and presents a solution to provision routing paths so a Fibbing network can still apply LFA in the network. The proposed network jointly considers load-balanced and fast failure recovery. We formulate the problem as an integer linear programming problem. The numerical results reveal that the proposed method can provide 100% survivability against any single node or single link failure.

Quantum interference effects in multi-channel correlated tunneling structures

In multi-channel tunneling systems quantum interference effects modify tunneling conductance spectra due to Fano effect. We investigated the impact of Hubbard type Coulomb interaction on tunneling conductance spectra for the system formed by several interacting impurity atoms or quantum dots localised between the contact leads. It was shown that the Fano shape of tunneling conductance spectra strongly changes in the presence of on-site Coulomb interaction between localised electrons in the intermediate system. The main effect which determines the shape of the tunneling peaks could be not Fano interference but mostly nonequilibrium dependence of the occupation numbers on bias voltage.

A Model Reduction Method for Bladed Disks with Large Geometric Mistuning Using a Partially Reduced Intermediate System Model

Reduced order models (ROMs) are widely used to enable efficient simulation of mistuned bladed disks. ROMs based on projecting the system dynamics into a subspace spanned by the modes of the tuned structure work well for small amounts of mistuning. When presented with large mistuning, including changes of geometry and number of finite element mesh nodes, advanced methods such as the the pristine-rogue-interface modal expansion (PRIME) are necessary. PRIME builds a reduced model from two full cyclic symmetric analyses, one for the nominal and one for the modified type of sector. In this paper a new reduced order model suitable for large mistuning with arbitrary mesh modifications is presented. It achieves higher accuracy than PRIME, while saving approximately 25% computational effort during the reduction process, when using the same number of cyclic modes. The new method gains its efficiency by recognizing that large modifications from damage or repair are unlikely to be exactly the same for multiple blades. It works by building a partially reduced intermediate model: All nominal sectors are reduced using cyclic modes of the tuned structure. The single modified sector is kept as the full model. For this reason, the new reduction method is called Partially Reduced Intermediate System Model (PRISM) method. The accuracy of the PRISM method is demonstrated on an axial compressor blisk and an academic blisk geometry.

EVALUASI KUALITAS AIR WADUK BERDASARKAN PARAMETER FISIKA

Reservoir is a large building made by humans by damming a river (Wetzel, 2001). Reservoirs are also an intermediate system between rivers (lotic waters) and lakes (lentic waters). The manufacture of reservoirs generally has objectives and functions, one of which is for raw water needs from drinking water treatment. MG Reservoir is the main source of raw water for PDAM Balikpapan City. MG Reservoir is a very important aquatic resource in terms of its ecological and economic functions. Therefore it must be maintained both in terms of quantity and quality. With the existence of various human activities around MG Reservoir, it will affect the condition of the reservoir. Keywords— evaluation, quality, physics, temperature, transparency, electrical conductivity

A Model Reduction Method for Bladed Disks With Large Geometric Mistuning Using a Partially Reduced Intermediate System Model

Reduced order models (ROMs) are widely used to enable efficient simulation of mistuned bladed disks. ROMs based on projecting the system dynamics into a subspace spanned by the modes of the tuned structure work well for small amounts of mistuning. When presented with large mistuning, including changes of geometry and number of finite element mesh nodes, advanced methods such as the the pristine-rogue-interface modal expansion (PRIME) are necessary. PRIME builds a reduced model from two full cyclic symmetric analyses, one for the nominal and one for the modified type of sector. In this paper a new reduced order model suitable for large mistuning with arbitrary mesh modifications is presented. It achieves higher accuracy than PRIME, while saving approximately 25% computational effort during the reduction process, when using the same number of cyclic modes. The new method gains its efficiency by recognizing that large modifications from damage or repair are unlikely to be exactly the same for multiple blades. It works by building a partially reduced intermediate model: All nominal sectors are reduced using cyclic modes of the tuned structure. The single modified sector is kept as the full model. For this reason, the new reduction method is called Partially Reduced Intermediate System Model (PRISM) method. The accuracy of the PRISM method is demonstrated on an axial compressor blisk and an academic blisk geometry.

Attacks and damage of termites (Insecta: Isoptera) in different cocoa agroforestry systems (Nawa, Côte d’Ivoire).

To maintain its status of leading producer of cocoa in the world, Côte d'Ivoire must be contain the different types of threats, including the emergence of termites in cocoa farms. This study was conducted in the south-west of the country to evaluate the effect of cropping systems (full sun system, intermediate system and shaded system) on termite attacks. The study was conducted in four localities with different cocoa agroforestry systems. The sampling was made on cocoa trees in quadrats of 30mx30m and the attack rate was calculated. Eleven (11) termite species were identified. The wood-feeders groups were dominant. These termites were responsible for 41.82% of the damage on cocoa trees. Termite Attacks vary between different cropping systems. Full sun systems were most attacked comparing to intermediate shade systems that were least attacked by termites. This work shows that the shade system has an effect on termite attacks in cacao trees. The choice of right system can help to significantly reduce termite attacks in cocoa farms.

The global environment of small galaxy systems

ABSTRACT The main goal of this work is to investigate the influence of environment at different scales on the properties of galaxies in systems with a low number of members. To this end, we used a catalogue of small galaxy systems comprising compact and locally isolated pairs, triplets, and groups with four and up to six galaxies. We consider fixed aperture estimators and found that at scales lower than 5 ${\ \rm Mpc}$ pairs are associated to lower density environments than triplets and groups. Moreover, a nearest neighbour approach highlights that triplets prefer denser environments than pairs and slightly less dense environments than groups. When considering the position within the cosmic web we found that pairs and triplets in our sample are associated to void environments while galaxy groups are more likely to reside in void walls. In agreement with these results, the system-galaxy cross-correlation function shows that pairs inhabit environments of lesser density compared to triplets and groups, and on small scales ($\lt\! 3{\ \rm Mpc}$) triplets appear to behave as an intermediate system. Related to the properties of neighbour galaxies of small systems we found that the neighbours of groups present a lower fractions of star-forming, young stellar population, and blue colour galaxies with respect to neighbours of triplet and pair systems. These results suggest that differences in the properties of galaxies in pairs, triplets, and groups are not only related to the existence of an extra galaxy member but also to the large-scale environment inhabited by the systems.