Engineering Reports

The output voltage of photovoltaic panels is variable and must be conditioned through a DC-DC converter to meet the demands of the interconnecting device. These systems must be modeled as a set of differential algebraic equations which complicates their analysis. This article derives a method to find the eigenvalues of PV-fed DC-DC converters through an adaptation to the Filippov method in order to find the saltation matrix.

Peptide nucleic acids are DNA/RNA synthetic analogs. They show unique stability and hybridization properties and have enormous biomedical applications for diagnostics (utilizing biosensors, microarray, and so on) and therapeutics. Hence, this review emphasizes the PNAs biomedical application along with its properties, synthesis, and prospects.

Computational FEA “test specimens” were used to model the effects of surface roughness and subsurface porosity on materials subjected to cyclic loading. This work was contrasted with a discussion of airworthiness assessment for Additively Manufactured components, as a step toward being able to quantify parameters used in lifing based on measurable geometry and established engineering physics principles.

This study aimed to evaluate the performance of CHIRPS satellite-based rainfall products in Finchaa and Neshe watersheds of the Blue Nile Basin for a time slice of 25 years (1991–2015). The result showed that the CHIRPS satellite product tends to slightly overestimate the mean rainfall depth in the study area and it indicated a positive strong linear correlation (R = 0.93 and R² = 0.86) and a smaller amount of noise, bias, and error (NSE = 0.84, PBIAS = 0.98%, and RMSE = 46.99 mm) compared with a ground-based measurement rainfall product.

A new FEM-based modeling strategy for textile structures that employs only beam and shell elements, is here proposed. The modeling capabilities for plain woven and biaxial reinforced fabrics are demonstrated. Forming simulations are used for benchmarking the model's performance.

The Q/V band communication systems open new avenues for next generation of high-throughput satellite (HTS) systems. More specifically, they are attractive due to their high bandwidth for user and gateway links. Having a wide bandwidth at Q/V band makes it permissible to offload the links between the satellite and its earth station hubs (gateway) from the Ka band to the Q/V band. This enables additional bandwidth available for HTS feeder links and user links of specific market verticals, which in turn results in reduction of cost per bit for in-flight connectivity applications to provide WiFi capability on the aircraft. This study provides a deep overview of network architecture at the ground gateway infrastructure with respect to the network management system (NMS) to optimize network traffic utilization. We have looked at a gateway constellation platform which optimizes the actual cost-efficient solution for deploying routing user traffic among the networks. In addition, the study discusses the elements involved in the NMS which interfaces with the gateway platform. The overall NMS platform design and capabilities are discussed as they provision the network service parameters throughout the entire operation. The proposed solution integrates the physical antenna, antenna control unit and the power supply into one bundle on the aircraft. This will result in approximately 10% throughput increase compared to conventional methods that do not deploy N+P gateway architecture. The proposed method has enhanced spectrum efficiency along with the NMS unit that has been discussed in detail. Finally, a wideband and multibeam antenna is introduced as an essential part of the solution followed up by simulation results.

With the development of energy harvesting technologies and smart grid, the future trend of radio access networks will present a multi-source power supply. In this article, joint renewable energy cooperation and resource allocation scheme of the fog radio access networks (F-RANs) with hybrid power supplies (including both the conventional grid and renewable energy sources) is studied. In this article, our objective is to maximize the average throughput of F-RAN architecture with hybrid energy sources while satisfying the constraints of signal to noise ratio (SNR), available bandwidth, and energy harvesting. To solve this problem, the dynamic power allocation scheme in the network is studied by using Q-learning and Deep Q Network respectively. Simulation results show that the proposed two algorithms have low complexity and can improve the average throughput of the whole network compared with other traditional algorithms.

“Multi-station integration” (MSI), as a novel business model can improve the energy utilization efficiency and promote the cross-border business integration. Therefore, the quantitative analysis about MSI spatial diffusion in Chinese eight economic zones can boost the popularity of MSI.

A new kind of equiangular spiral blade vertical axis wind turbine is designed on the basis of the diagonal spiral. The wind turbine is simply improved by changing the pitch angle, and the 110° pitch angle blade with better performance is selected through the comparison of the simulation calculation method.

Lack of conventional sources of energy, high demand for energy, less available land, and low budget for energy are some of the important factors that cause poor energy management all over the world. In this article, different potential less implemented sources of energy are analyzed along with their implementation techniques to mitigate high electricity demand in near-future.

In this study, a noncooperative multiagent game model for the electricity market was developed on the basis of the recently released RPS and by considering various factors, such as green certificate transactions and the changing of the selling entities. The improved firefly algorithm was used to solve the model, and problematic gaming was analyzed empirically.

Recycling rubber tires in building envelopes contributes to increasing the efficiency of thermal insulation, which reduces the energy consumption needed to provide comfort to its occupants and protects the environment from the spread of waste tires and their negative consequences on public health.

This paper proposes a novel method for detecting, classifying and locating the high impedance fault zone in a distribution system. This paper proposed novel graph theory-based zone selection technique along with a Random Search Multilevel Support Vector Machine (RSMSVM) algorithm to classify fault zone.