by Guanghui Wang
Original Research
Effective support of emergency materials is a necessary prerequisite for post-disaster emergency rescue. The transportation and distribution of post-disaster emergency materials includes two stages: from storage warehouses and material distribution centers outside the disaster area to emergency distribution centers outside the disaster area, and from emergency distribution centers to rescue points in the disaster area. Emergency material support has the characteristics of urgent demand and relative shortage of materials. Especially, the transportation of materials from supply points outside the disaster-stricken areas to emergency material distribution centers, along the way, affected by the actual traffic capacity and meteorological conditions, will have a significant impact on the efficient distribution of emergency materials. This paper deals with the optimization of transportation allocation from emergency material supply points to emergency material distribution centers in the periphery of disaster areas. Based on the factors affecting transportation efficiency such as road resistance parameters, attenuation coefficient, and disaster intensity, an optimal allocation model of emergency materials is established, which minimizes the sum of transportation cost, construction cost of distribution center, and penalty cost of transportation time. The validity and feasibility of the model are analyzed and studied by an example. The experimental results show that the attenuation coefficient of the transportation line and the disaster intensity of the road section have important influence on the emergency material allocation scheme. The emergency material allocation scheme formulated by the optimization model is scientific and reasonable.
American Journal of Electrical and Electronic Engineering. 2019, 7(3), 83-90. DOI: 10.12691/ajeee-7-3-5
Pub. Date: September 05, 2019
11531 Views2674 Downloads5 Likes
by Pahalson C. A. D., Tarkaa N. S. and Habila Nuhu
Original Research
Ever increasing demand for communication services has led to serious challenges to network operators to ensure acceptable Quality of Service (QoS) at minimum cost. The increasing number of subscribers and demand for greater variety of services make it difficult for network operators to provide the service varieties subscribers want while maintaining acceptable levels of quality of service. Spectrum is a precious commodity, knowing how efficiently different technologies and applications use it allows users and operators to make the best decisions on what wireless technology to deploy and in what configuration. Spectrum efficiency is an important parameter for accessing the frequency requirements of cellular mobile radio systems; radio channel capacity is a measure of the spectrum efficiency of a wireless system. The effect of cluster size, carrier to interference ratio and carried traffic in the spectrum efficiency are discussed. The fundamental figure of merit is the spectral efficiency was found to be 1.3698 fall within the regulator and defined items of Erlangs/MHz/Km2proved to be adequate, comprehensive, and appropriate for cellular system. It is also observed that the smallest value of C/I ratio provides largest spectrum efficiency. Comparatively, the study of the 120°sectored and 60°sectored cells can be done in relation to non-sectored (omnidirectional, 360°) cells when a number of interfering base stations are considered. The performance of improvement of the 60° sectored provides better coverage performance than 120° sectored and Omni. Low C/I ratio will cause coverage issue including dropped calls, block calls, and other handset reception problem.
American Journal of Electrical and Electronic Engineering. 2019, 7(3), 75-82. DOI: 10.12691/ajeee-7-3-4
Pub. Date: September 01, 2019
9477 Views1558 Downloads1 Likes
by Jie Lv, Wei Qiu, Ying Wang and Gang Ma
Original Research
With the rapid development of household photovoltaics and electric vehicles, demand-side energy management has become an important means to release the burden of power grid during the load peaking period. In order to ensure the user comfort and reduce the cost of electricity, a multi-time scale home energy management method is proposed based on mixed integer programming algorithm. Firstly, on the basis of time-of-use electricity price, household photovoltaic, electric vehicles, storage batteries and HVAC are taken into consideration. And then, short time scale model of HVAC is adopted, which increases the rationality of modeling while discretizing. The simulation results verify the superiority of multi-time scale and the optimization effect of the proposed method, which can reduce the cost of electricity for users, smooth the load curve and improve the utilization efficiency of renewable energy.
American Journal of Electrical and Electronic Engineering. 2019, 7(3), 69-74. DOI: 10.12691/ajeee-7-3-3
Pub. Date: August 18, 2019
8514 Views1477 Downloads2 Likes
by Olusegun Ogundapo, Charles Nche, Alistair Duffy and Gang Zhang
Original Research
The use of Ethernet cables is a vital, if under- discussed element of the infrastructure for the internet of things (IOT). While there are many cable types on the market, one worrying trend is the wide availability of copper clad aluminum (CCA) cables, which are widely considered unsuitable for infrastructure deployment. The availability of these copper clad aluminum (CCA) cables frequently disguised as compliant Ethernet communication cables calls for a method of assessing their performance, as this is crucial to ensuring quality of service delivery. This paper presents a method of analyzing the measured return loss and impedance profile due to handling stress. In this research, four Ethernet cables of which one of them was copper CCA cable were subjected to three rounds of coiling and uncoiling tests to represent stress from handling during installation. The Feature Selective Validation (FSV) method and Kolmogorov-Smirnov (KS) tests were used to quantify the variations between the tests. The results indicate that the CCA cable has the lowest resilience to physical stress with high potential for degradation.
American Journal of Electrical and Electronic Engineering. 2019, 7(3), 55-61. DOI: 10.12691/ajeee-7-3-1
Pub. Date: August 08, 2019
18321 Views1502 Downloads2 Likes