针对非同构分布式阵列无法使用旋转不变子空间算法(estimation of signal parameters via rotation invariant technique algorithm,ESPRIT),同时为了提高非同构分布式阵列的角度估计精度,提出基于求根降秩算法(root rank reduction est...针对非同构分布式阵列无法使用旋转不变子空间算法(estimation of signal parameters via rotation invariant technique algorithm,ESPRIT),同时为了提高非同构分布式阵列的角度估计精度,提出基于求根降秩算法(root rank reduction estimator,root-RARE)的目标波达方向估计方法。由于分布式阵列的基线长度远大于半波长,合成方向图出现栅瓣,导致测角模糊。算法以root-RARE与多重信号分类算法(multiple signal classification,MUSIC)联合解模糊,以root-RARE得到的粗估计为参考,解整个非同构分布式阵列MUSIC谱估计的模糊,从而得到高精度无模糊的估计。推导非同构分布式阵列方向估计的克拉美罗界,分析算法的波达方向估计性能,同时分析分布式阵列方向估计时的基线模糊门限与信噪比门限之间的关系。仿真结果验证所提算法方向估计的正确性及有效性。展开更多
This paper introduces a novel variant of particle swarm optimization that leverages local displacements through attractors for addressing multiobjective optimization problems. The method incorporates a square root dis...This paper introduces a novel variant of particle swarm optimization that leverages local displacements through attractors for addressing multiobjective optimization problems. The method incorporates a square root distance mechanism into the external archives to enhance the diversity. We evaluate the performance of the proposed approach on a set of constrained and unconstrained multiobjective test functions, establishing a benchmark for comparison. In order to gauge its effectiveness relative to established techniques, we conduct a comprehensive comparison with well-known approaches such as SMPSO, NSGA2 and SPEA2. The numerical results demonstrate that our method not only achieves efficiency but also exhibits competitiveness when compared to evolutionary algorithms. Particularly noteworthy is its superior performance in terms of convergence and diversification, surpassing the capabilities of its predecessors.展开更多
Let Φ be an irreducible root system of classical type. In t his short note, we study the irreducible subsystems of Φ and compute the nu mber of irreducible subsystems of any rank k in Φ.
The efficient use of water by modern irrigation systems is becoming increasingly important in arid and semi-arid regions with limited water resources. Field experiments were conducted during 2008-2010 to study the eff...The efficient use of water by modern irrigation systems is becoming increasingly important in arid and semi-arid regions with limited water resources. Field experiments were conducted during 2008-2010 to study the effect of drip fertigation with water soluble fertilizer on root growth of maize under maize based intercropping system. The experiment was laid out in strip plot design with three replications. The treatment consists of nine fertigation levels in main plots and four inter crops in sub plots. Root spread and root dry mass were increased under drip fertigation practices while rooting depth was more under surface irrigation. Drip fertigation with water soluble fertilizer improved the root system by inducing new secondary roots which are succulent and actively involved in physiological responses. Drip fertigation has pronounced effect on the root architecture especially in the production of highly fibrous root system.展开更多
An analysis of a base-isolated structure for multi-component random ground motion is presented. The mean square respond of the system is Obtained under different parametric variations. The effectiveness of main param...An analysis of a base-isolated structure for multi-component random ground motion is presented. The mean square respond of the system is Obtained under different parametric variations. The effectiveness of main parameters and the torsional component during an earthquake is quantified with the help of the response ratio and the root mean square response with and without base isolation. It is observed that the base isolation has considerable influence on the response and the effect of the torsional component is not ignored.展开更多
Agricultural pollution is a major issue in the United States (U.S.) and the world. Biotic and abiotic farming byproducts adversely affect the ecosystem and human health. While pesticides and fertilizers are the primar...Agricultural pollution is a major issue in the United States (U.S.) and the world. Biotic and abiotic farming byproducts adversely affect the ecosystem and human health. While pesticides and fertilizers are the primary sources of agricultural pollution, organic agriculture can help remediate the negative effects on humans and the ecosystem. However, many factors like chemical drift can limit this advantage. This paper presents a feasibility study of a web-based (Geografic Information System) GIS application which can model and predict the areas affected by agricultural chemicals drift. Other applications exist with limited assumptions that make their outcomes far from reality. A root definition and a rich picture are developed as well as a Strengths Weaknesses Opportunities and Threats (SWOT) analysis. Because of the huge geographical context, data requirements and analyses requirements are expected to be massive. Nonetheless, despite the expected challenges, the advantages of the proposed application outweigh the risks.展开更多
文摘针对非同构分布式阵列无法使用旋转不变子空间算法(estimation of signal parameters via rotation invariant technique algorithm,ESPRIT),同时为了提高非同构分布式阵列的角度估计精度,提出基于求根降秩算法(root rank reduction estimator,root-RARE)的目标波达方向估计方法。由于分布式阵列的基线长度远大于半波长,合成方向图出现栅瓣,导致测角模糊。算法以root-RARE与多重信号分类算法(multiple signal classification,MUSIC)联合解模糊,以root-RARE得到的粗估计为参考,解整个非同构分布式阵列MUSIC谱估计的模糊,从而得到高精度无模糊的估计。推导非同构分布式阵列方向估计的克拉美罗界,分析算法的波达方向估计性能,同时分析分布式阵列方向估计时的基线模糊门限与信噪比门限之间的关系。仿真结果验证所提算法方向估计的正确性及有效性。
文摘This paper introduces a novel variant of particle swarm optimization that leverages local displacements through attractors for addressing multiobjective optimization problems. The method incorporates a square root distance mechanism into the external archives to enhance the diversity. We evaluate the performance of the proposed approach on a set of constrained and unconstrained multiobjective test functions, establishing a benchmark for comparison. In order to gauge its effectiveness relative to established techniques, we conduct a comprehensive comparison with well-known approaches such as SMPSO, NSGA2 and SPEA2. The numerical results demonstrate that our method not only achieves efficiency but also exhibits competitiveness when compared to evolutionary algorithms. Particularly noteworthy is its superior performance in terms of convergence and diversification, surpassing the capabilities of its predecessors.
文摘Let Φ be an irreducible root system of classical type. In t his short note, we study the irreducible subsystems of Φ and compute the nu mber of irreducible subsystems of any rank k in Φ.
文摘The efficient use of water by modern irrigation systems is becoming increasingly important in arid and semi-arid regions with limited water resources. Field experiments were conducted during 2008-2010 to study the effect of drip fertigation with water soluble fertilizer on root growth of maize under maize based intercropping system. The experiment was laid out in strip plot design with three replications. The treatment consists of nine fertigation levels in main plots and four inter crops in sub plots. Root spread and root dry mass were increased under drip fertigation practices while rooting depth was more under surface irrigation. Drip fertigation with water soluble fertilizer improved the root system by inducing new secondary roots which are succulent and actively involved in physiological responses. Drip fertigation has pronounced effect on the root architecture especially in the production of highly fibrous root system.
文摘An analysis of a base-isolated structure for multi-component random ground motion is presented. The mean square respond of the system is Obtained under different parametric variations. The effectiveness of main parameters and the torsional component during an earthquake is quantified with the help of the response ratio and the root mean square response with and without base isolation. It is observed that the base isolation has considerable influence on the response and the effect of the torsional component is not ignored.
文摘Agricultural pollution is a major issue in the United States (U.S.) and the world. Biotic and abiotic farming byproducts adversely affect the ecosystem and human health. While pesticides and fertilizers are the primary sources of agricultural pollution, organic agriculture can help remediate the negative effects on humans and the ecosystem. However, many factors like chemical drift can limit this advantage. This paper presents a feasibility study of a web-based (Geografic Information System) GIS application which can model and predict the areas affected by agricultural chemicals drift. Other applications exist with limited assumptions that make their outcomes far from reality. A root definition and a rich picture are developed as well as a Strengths Weaknesses Opportunities and Threats (SWOT) analysis. Because of the huge geographical context, data requirements and analyses requirements are expected to be massive. Nonetheless, despite the expected challenges, the advantages of the proposed application outweigh the risks.
