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Due to restrictions on lead usage often resulting in the use of pure tin deposits, coupled with global miniaturization, the unpredictable risks of Sn whisker growth rises, especially in highly stressed coating applications. The ability to prevent whisker growth is particularly important for the growing implementations of solderless press-fit pin connections, where although very beneficial, produce...
The Ecuadorian electricity sector is a strategic area of the country, whose general objective is to Generate, Transmit, Distribute and Commercialize electrical energy. In 2009, the Ministry of Electricity and Renewable Energy (MEER) and the Electric Utilities of Ecuador signed an agreement for institutional cooperation to strengthen the electricity distribution sector with the objective of achieving...
Demand Side Management (DSM) has been become a popular option for improving electricity system operations and reliability. Moreover, Demand Response (DR) programs provide superior efficiency and flexibility to their users. This paper proposes a method to assess system reliability and evaluate the specific contributions made by spinning reserves (SR) and DR. The method structurally and spatially decomposes...
A solid and practical approach for designing an optimal secondary distribution network is proposed. The methodology starts by optimally locating and sizing medium voltage/low voltage transformers then finding the optimal path for secondary circuits. The optimal number of transformers and their location are determined by k-means clustering algorithm, and validated using Davies-Bouldin index. In addition,...
This paper presents an assessment of the impacts of Demand Response (DR) programs and distributed generation (DG) in the chargeability of the Colombian power system. Initially, several indexes are defined to account for the impact of single contingencies in the chargeability of the Colombian power system under different operative scenarios. Then, the most critical operative scenario in terms of number...
The emerging potential of distributed generation (DG) is feasible to be conducted through microgrids implementation. A microgrid is a portion of the electrical system which views generation and associated loads as a subsystem, with the ability to operate both grid connected or islanded from grid, thus maintaining a high level of service and reliability. The existing grid infrastructure, the distributed...
This paper presents a multi-start optimization algorithm that performs the simultaneous reconfiguration of feeders and allocation of capacitor banks in radial distribution systems. The objective is to find an optimal operating topology for the system together with an optimal plan of investment and operation for capacitor banks that minimizes the operating and investment costs over a chosen horizon...
Soft ferrite materials are widely used in the construction of high frequency transformer for power electronic applications. Core loss calculation is essential both in the selection of soft ferrites and the design of high frequency transformer. Traditionally, the Steinmetz equation is used to evaluate the core loss of magnetic materials under sinusoidal excitation. Nevertheless, in modern power electronics,...
In order to supplement the saaty's consistency theory of judgment matrix, the experts’ psychological expectation of the comparative scale values is studied. The omission of the saaty's consistency theory is analyzed. An innovative consistency definition of judgment matrix is proposed. A matrix adjustment method is developed from this definition. This method is compared with the existing methods from...
A polarization converter (PC) based on the mode coupling in a hybrid plasmonic waveguide (HPW) is proposed. This PC comprises a Si core, a low index insulator layer surrounding the Si core, and two asymmetrically arranged Ag strips. Two orthogonal hybrid polarization modes are excited within the low index insulator layer. By exploiting the mode characteristics of these two hybrid polarization modes,...
There is a trend that the functionalities of communication, computing, and caching (CC&C) are merging together in the future networks. Recently, this mergence is formed by the concept of cloud radio access network (C-RAN) with caching as a service (CaaS). In this paper, we dissect the interactions of CC&C in C-RAN with CaaS from two dimensions: physical resource dimension and time dimension...
In this paper, a novel two-phase orthogonal frequency division multiplexing-index modulation (OFDM-IM)-aided cooperative relaying protocol is proposed for overlay cognitive radio (CR) networks, where the primary and secondary networks work concurrently over the same spectrum band. In the proposed scheme, OFDM-IM technique is used at the secondary user (SU) to split the transmission space into the...
Decentralized coded caching is applicable in scenarios where the server does not have enough knowledge about the entire cache network to perform centralized coordination during prefetching, such as when the server is uninformed of the number of active users and their identities in a wireless or mobile environment. Most of known decentralized strategies use random uncoded prefetching followed by coded...
Using parallel manipulator into free-form surface polishing process has become a kind of trend, the parallel polishing manipulator system with dynamic feed-forward control which can improve the system response speed and control precision. This will guarantee the practical application and commercially of the parallel polishing machine tool. This paper bases on five degree of freedom parallel polishing...
To improve the loading environment, the spacecraft reliability, and reduce the launch risks, the thesis is based on the application of whole-spacecraft vibration isolation, and to design a vibration isolation platform is built by three degree-of freedom parallel mechanism. The kinematics of the mechanisms was analyzed, the dynamics models considering the rotation stiffness of the flexure hinges was...
A design method for ultrasonic torsional transducer is presented based on the one-dimensional wave equation and the equivalent circuit method. Firstly, the equivalent circuits of torsional transducer and horn are constructed. The mounting flange can be placed right at the nodal plane, where no angular displacement occurs. An ultrasonic torsional tool is fabricated according to the presented method,...
In deep neural networks, inputs in each layer are affected by all previous parameters of input layers, so even small changes in input distributions to the network are delivered to internal layers, for leading to differences between source domain and target domain, which is known as covariate shift. Batch Normalization(BN) is designed to address the issue, and makes normalization for each training...
In this paper, analog-and-digital hybrid beamformer design is considered for millimeter-wave (mmWave) wideband multi-user (MU) multiple-input single-output (MISO)-OFDM downlink systems, where a single common analog beamformer is used for all subcarriers while a separate digital beamformer is applied to each subcarrier. By applying a signal-to-leakage-plus-noise ratio (SLNR) approach, an efficient...
With the rapid development of remote sensing data, the instant and high-efficient analysis on remote sensing image become a challenge. In our research, we adopt the main idea of Merkle Tree and incorporate it with the regular quad-tree to generate an advanced Merkle Quad-Tree structure to assist the remote sensing image analysis. A series of experiments are conducted to authenticate the advantages...
Mixed pixels have a significant impact on the accurate estimation of Fractional Vegetation Cover (FVC) using digital photos acquired by Unmanned Aerial Vehicle (UAV). A single threshold is inadequate for the separation of vegetation and background when images contain numerous mixed pixels. We propose a spectral unmixing method to measure FVC with UAV-acquired digital images. In this method, the spectral...
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