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1.
Efficient electricity price forecasting plays a significant role in our society. In this paper, a novel influencer-defaulter mutation (IDM) mutation operator has been proposed. The IDM operator has been combined with six well-known optimization algorithms to create mutated optimization algorithms whose performance has been tested on twenty-four standard benchmark functions. Further, the artificial neural network is integrated with mutated optimization algorithms to solve the electricity price prediction problem. The policymakers can identify appropriate variables based on the predicted prices to help future market planning. The statistical results prove the efficacy of the IDM operator on the recent optimization algorithms.  相似文献   
2.
This paper presents the development and implementation of an innovative mixed integer programming based mathematical model for an open pit mining operation with Grade Engineering framework. Grade Engineering comprises a range of coarse-separation based pre-processing techniques that separate the desirable (i.e. high-grade) and undesirable (i.e. low-grade or uneconomic) materials and ensure the delivery of only selected quantity of high quality (or high-grade) material to energy, water, and cost-intensive processing plant. The model maximizes the net present value under a range of operational and processing constraints. Given that the proposed model is computationally complex, the authors employ a data pre-processing procedure and then evaluate the performance of the model at several practical instances using computation time, optimality gap, and the net present value as valid measures. In addition, a comparison of the proposed and traditional (without Grade Engineering) models reflects that the proposed model outperforms the traditional formulation.  相似文献   
3.
周期性隔震基础是利用周期性结构的衰减域特性,将地震动与上部结构自振频率接近的频率范围内的能量衰减,从而控制上部结构响应的新型隔震装置。周期性基础的隔震性能受到多方面因素的影响,包括局域共振子的调谐频率比、质量比、阻尼比、基体的刚度、上部结构与基础的相互作用以及地震动的频谱特性等。目前尚未有研究综合考虑上述因素的影响并提出周期性基础的设计方法。提出以一组地震动作用下上部结构峰值响应衰减率的平均值为目标函数,对周期性基础进行优化的设计方法。计算结果表明,按照该优化方法得到的周期性基础对上部结构在选取的44条地震动作用下,峰值响应的平均衰减率达30%。参数敏感性分析表明,优化设计得到的周期性基础对于自身参数的变化具有良好的鲁棒性。最后利用缩尺振动台试验验证了优化设计得到的周期性基础的隔震性能,证明了优化方法的有效性和优化结果的正确性。  相似文献   
4.
《工程(英文)》2020,6(7):812-826
Renewable energy sources (RESs) are considered to be reliable and green electric power generation sources. Photovoltaics (PVs) and wind turbines (WTs) are used to provide electricity in remote areas. Optimal sizing of hybrid RESs is a vital challenge in a stand-alone environment. The meta-heuristic algorithms proposed in the past are dependent on algorithm-specific parameters for achieving an optimal solution. This paper proposes a hybrid algorithm of Jaya and a teaching–learning-based optimization (TLBO) named the JLBO algorithm for the optimal unit sizing of a PV–WT–battery hybrid system to satisfy the consumer’s load at minimal total annual cost (TAC). The reliability of the system is considered by a maximum allowable loss of power supply probability (LPSPmax) concept. The results obtained from the JLBO algorithm are compared with the original Jaya, TLBO, and genetic algorithms. The JLBO results show superior performance in terms of TAC, and the PV–WT–battery hybrid system is found to be the most economical scenario. This system provides a cost-effective solution for all proposed LPSPmax values as compared with PV–battery and WT–battery systems.  相似文献   
5.
栖霞—大柳行地区位于胶东中部栖霞—蓬莱金矿成矿带内,是胶东重要的金成矿区,成矿条件优越。为了对圈定靶区进行优选分类,通过对该区地质背景、找矿靶区评价、找矿靶区优选方面展开综合研究,并结合勘查工作程度和矿业权设置情况,划分出3类预测区,选定了5个靶区为今后优先部署勘查工作的方向。  相似文献   
6.
Secondary risk in project risk management refers to the risk that arises as a direct result of implementing a risk response action (RRA). It is important for project managers (PMs) to consider the effects caused by the secondary risks in the process of RRA selection. The purpose of this paper is to propose an optimization method to address the problem of selecting risk response actions (RRAs) with consideration of secondary risk which is seldom considered in the existing studies. The optimization model aims to minimize the total risk costs with time constraint being placed on the project makespan. By solving the model, an optimal set of RRAs along with the earliest start time for each activity can both be obtained. The results show that secondary risk plays an important role in the process of RRA selection. Project managers should allocate more budget for responding the project risk when the secondary risk is considered, and consider all factors relating to both time and cost so as to select appropriate RRAs to mitigate primary risk and secondary risk.  相似文献   
7.
A modeling theory is developed to predict the performance of piezoresistors which incorporate Schottky diode electrical contacts. This new theory allows the design of high performance gauges which can be fabricated using Non-Lithographically-Based Microfabrication (NLBM) techniques. These semiconductor piezoresistors can be designed in customizable sizes and fabricated in parallel in order to integrate position sensing into MEMS flexural positioners. Customizable sensing for nanopositioning platforms will enable advances in a range of nano-scale fabrication and metrology applications. A semiconductor piezoresistor with Schottky diode contacts was fabricated and attached to a titanium flexure. This device is shown to match predicted electrical performance within about 8% and to show a gauge factor of 116, within 2% of the predicted value. Optimized performance limits for Schottky diode semiconductor piezoresistors are identified to be about 127 dB full noise dynamic range for a quarter bridge over a 10 kHz sensor bandwidth on a 600 μm width titanium flexure, making them ideal for sensing on meso-/micro-scale flexural positioners. Methods are suggested for achieving the performance limits indicated above and the impact of these methods on the sensor dynamic range are studied.  相似文献   
8.
The ability of landscape architectural projects to mitigate the worst effects of climate change will depend upon designed ecological systems. These systems will be built with plants. Despite the recognition of ecology as an essential driver of landscapes, the professionals of landscape architecture too often lack the knowledge and practical skills to create robust vegetative systems. New approaches and tools are required. This article outlines principles and methods for designing biodiverse plant systems for urban sites. Planting methods that increase species richness, functional diversity, and spatial complexity are emphasized as a way of developing more resilient plantings. Selecting species with similar evolutionary adaptions to stress, disturbance, and competition—as well as creating multi-layered compositions of diverse plant morphologies—allows designers to create compatible, long-lived plant mixes. To balance the increased visual complexity of diverse plant mixes, the article explores design techniques to make plantings more appealing to the public. The strategies explored here are based on the projects, experience, and research of Phyto Studio, a Washington, D.C. based studio. The methods build on work described in the author’s book, Planting in a Post-Wild World, an exploration of how to create designed plant communities.  相似文献   
9.
With the development of new energy, hydrogen fuel engines have become a research boom in the automotive field. But there are abnormal problems such as backfire and pre-ignition during the combustion of hydrogen engines. This paper is based on the Ant Colony Optimization-Back Propagation (ACO-BP) algorithm to study the influence of different speed and load conditions on the ignition advance angle, so as to optimize the control of the hydrogen engine. The experimental system is established on a hydrogen engine converted from a 492Q gasoline engine. The prediction of the optimal ignition advance angle was obtained through experiments, and the optimal ignition MAP diagram of the hydrogen engine is constructed. The optimal ignition advance angle under different working conditions can effectively avoid the occurrence of hydrogen engine pre-ignition. The accuracy reaches 0.0018209 when the training reaches 14 times, the fitness between the actual value and the predicted value of ACO-BP training is 0.99921, the verification accuracy reaches 0.99913, and the test accuracy reaches 0.99932. Compared with the three optimization methods, the convergence speed and error accuracy of ACO-BP are significantly better than the BP neural networks and Genetic Algorithm-Back Propagation (GA-BP). This method realized the model of the nonlinear mapping model from hydrogen engine speed and load to optimal ignition advance angle, which is of great significance for solving the problem of abnormal combustion in hydrogen engine.  相似文献   
10.
机载空间激光通信视轴稳定是激光通信链路建立的前提。在视轴稳定平台中应用自抗扰控制方法取得了良好的控制效果,但自抗扰控制需调整参数众多且缺乏规范的调整手段。针对自抗扰控制调参难的问题,本文提出了一种利用双态混沌粒子群算法优化自抗扰控制参数的方法。仿真结果表明,与PSO-PID控制方法相比,该方法具有更快的响应速度,更强的抗干扰能力和更好的鲁棒性。  相似文献   
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