Water Supply Alternatives for the Tripoli Area, North-Western Libya

Source: ICHE Conference Archive - https://mdi-de.baw.de/icheArchiv

Heuristic Barycenter Modeling of Fully Absorbing Receivers in Diffusive Molecular Communication Channels

In a recent paper it has been shown that to model a diffusive molecular communication (MC) channel with multiple fully absorbing (FA) receivers, these can be interpreted as sources of negative particles from the other receivers' perspective. The barycenter point is introduced as the best position where to place the negative sources. The barycenter is obtained from the spatial mean of the molecules impinging on the surface of each FA receiver. This paper derives an expression that captures the position of the barycenter in a diffusive MC channel with multiple FA receivers. In this work, an analytical model inspired by Newton's law of gravitation is found to describe the barycenter, and the result is compared with particle-based simulation (PBS) data. Since the barycenter depends on the distance between the transmitter and receiver and the observation time, the condition that the barycenter can be assumed to be at the center of the receiver is discussed. This assumption simplifies further modeling of any diffusive MC system containing multiple FA receivers. The resulting position of the barycenter is used in channel models to calculate the cumulative number of absorbed molecules and it has been verified with PBS data in a variety of scenarios.Comment: 30 pages, 10 figure

Heuristic Barycenter Modeling of Fully Absorbing Receivers in Diffusive Molecular Communication Channels

In a recent paper it has been shown that to model a diffusive molecular communication (MC) channel with multiple fully absorbing (FA) receivers, these can be interpreted as sources of negative particles from the other receivers’ perspective. The barycenter point is introduced as the best position where to place the negative sources. The barycenter is obtained from the spatial mean of the molecules impinging on the surface of each FA receiver. This paper derives an expression that captures the position of the barycenter in a diffusive MC channel with multiple FA receivers. In this work, a heuristic model inspired by Newton’s law of gravitation is found to describe the barycenter, and the result is compared with particle-based simulation (PBS) data. Since the barycenter depends on the distance between the transmitter and receiver and the observation time, the condition that the barycenter can be assumed to be at the center of the receiver is discussed. This assumption simplifies further modeling of any diffusive MC system containing multiple FA receivers. The resulting position of the barycenter is used in channel models to calculate the cumulative number of absorbed molecules and it has been verified with PBS

Influence of palm oil fuel ash on physico-mechanical properties of prepacked aggregate concrete

Prepacked aggregate concrete (PAC) is a special type of concrete which is made by placing coarse aggregate in a formwork and injecting a grout either by pump or under gravity force to fill the voids. Utilization of pozzolanic materials in traditional concrete has become increasingly extensive, and this trend is expected to continue in prepacked concrete as well. Palm oil fuel ash (POFA) is one of the pozzolanic ashes, which has been recognized as a good pozzolanic material. This paper presents the results of some experimental tests on the performance behavior of POFA in developing physical and mechanical properties of prepacked aggregate concrete. Four concrete mixes namely prepacked concrete with 100% OPC as control, and PAC with 10%, 20% and 30% POFA were cast, and the temperature growth due to heat of hydration in all the mixtures was recorded. It has been found that POFA significantly reduced the temperature rise in prepacked concrete. The compressive and tensile strength, however, increased with replacement of POFA. The results obtained and the observation made in this study suggest that the replacement of OPC by POFA is beneficial, particularly for prepacked mass concrete where thermal cracking due to extreme heat rise is of great concern

On the Oscillation of the Generalized Food-Limited Equations with Delay

- The objective of the paper is to find conditions for the oscillation of the food-limited equation. We established conditions for the oscillation of all solutions of the generalized foodlimited equation by transforming the equation to a non-linear delay differential equation and then to a scalar delay differential equation and using the property of the scalar delay differential equation to obtain our result. Similarly we establish conditions for the oscillation of all solutions of the foodlimited equation with several delays by transforming the equation to a scalar differential equation to obtain the oscillatory property

Study of Distributed Slack Bus Model for Economic Dispatch of Renewable Energy

In this paper, a distributed slack bus (DSB) using combined participation factors based on scheduled generation capacities of the system is designed in order to distribute the system losses among the generators. A DSB algorithm is developed and implemented using a Newton Raphson (NR) solver on a MATLAB platform. The IEEE 14 bus is used as a case study. Renewable energy (RE) sources are introduced into the system and the generation cost compared between systems with renewable energy sources and those with only thermal generators in both the single slack bus (SSB) model and the DSB model. The DSB employed resulted in a reduction in overall real power generation from 272.593 MW to 272.409 MW in the 14 bus model and cost of generation also decreased in both buses. Real power line losses also reduced in the buses. The change in the generation levels of the voltage controlled buses resulted in a proper economic dispatch scheme which gave an accurate representation of the network parameters. The cost of generation is considerably reduced upon introduction of wind and solar generators into the system as compared to systems without these sources. An even more accurate network model is obtained by using combined participation factors