scholarly journals Aphid Identification and Counting Based on Smartphone and Machine Vision

2017 ◽  
Vol 2017 ◽  
pp. 1-7 ◽  
Author(s):  
Suo Xuesong ◽  
Liu Zi ◽  
Sun Lei ◽  
Wang Jiao ◽  
Zhao Yang
Keyword(s):  
Difference Method ◽  
Design Method ◽  
Transformation Method ◽  
Contour Detection ◽  
Second Step ◽  
Exact Enumeration ◽  
Single Image ◽  
Threshold Method ◽  
Random Illumination ◽  
Image Difference

Exact enumeration of aphids before the aphids outbreak can provide basis for precision spray. This paper designs counting software that can be run on smartphones for real-time enumeration of aphids. As a first step of the method used in this paper, images of the yellow sticky board that is aiming to catch insects are segmented from complex background by using GrabCut method; then the images will be normalized by perspective transformation method. The second step is the pretreatment on the images; images of aphids will be segmented by using OSTU threshold method after the effect of random illumination is eliminated by single image difference method. The last step of the method is aphids’ recognition and counting according to area feature of aphids after extracting contours of aphids by contour detection method. At last, the result of the experiment proves that the effect of random illumination can be effectively eliminated by using single image difference method. The counting accuracy in greenhouse is above 95%, while it can reach 92.5% outside. Thus, it can be seen that the counting software designed in this paper can realize exact enumeration of aphids under complicated illumination which can be used widely. The design method proposed in this paper can provide basis for precision spray according to its effective detection insects.

Leader-following consensus of heterogeneous linear multi-agent systems: New results based on linear transformation method

2021 ◽  
pp. 014233122110582
Author(s):  
Yangzhou Chen ◽  
Guangyue Xu ◽  
Jingyuan Zhan
Keyword(s):  
Linear Transformation ◽  
Design Method ◽  
Transformation Method ◽  
Consensus Problem ◽  
Multi Agent Systems ◽  
Consensus Protocol ◽  
Agent Systems ◽  
Hurwitz Stability ◽  
Leader Following ◽  
Multi Agent

This paper studies the leader-following state consensus problem for heterogeneous linear multi-agent systems under fixed directed communication topologies. First, we propose a consensus protocol consisting of four parts for high-order multi-agent systems, in which different agents are allowed to have different gain matrices so as to increase the degree of design freedom. Then, we adopt a state linear transformation, which is constructed based on the incidence matrix of a directed spanning tree of the communication topology, to equivalently transform the state consensus problem into a partial variable stability problem. Meanwhile, the results of the partial variable stability theory are used to derive a sufficient and necessary consensus criterion, expressed as the Hurwitz stability of a real matrix. Then, this criterion is further expressed as a bilinear matrix inequality condition, and, based on this condition, an iterative algorithm is proposed to find the gain matrices of the protocol. Finally, numerical examples are provided to verify the effectiveness of the proposed protocol design method.

Design Method for Lattice-Skin Structure Fabricated by Additive Manufacturing

2014 ◽  
Author(s):  
Yunlong Tang ◽  
Yaoyao Fiona Zhao
Keyword(s):  
Complex Geometry ◽  
Lattice Structure ◽  
Design Method ◽  
Mapping Function ◽  
Second Step ◽  
Parameter Distribution ◽  
Skin Structure ◽  
Traditional Design ◽  
Novel Design

Parts with complex geometry structure can be produced by AM without significant increase of fabrication time and cost. One application of AM technology is to fabricate customized lattice-skin structure which can enhance performance of products with less material and less weight. However, most of traditional design methods only focus on design at macro-level with solid structure. Thus, a design method which can generate customized lattice-skin structure for performance improvement and functionality integration is urgently needed. In this paper, a novel design method for lattice-skin structure is proposed. In this design method, FSs and FVs are firstly generated according to FRs. Then, initial design space is created by filling FVs and FSs with selected lattice topology and skin, respectively. In parallel to the second step, initial parameters of lattice-skin structure are calculated based on FRs. Finally, TO method is used to optimize parameter distribution of lattice structure with the help of mapping function between TO’s result and lattice parameters. The design method proposed in this paper is proven to be efficient with case study and provides an important foundation for wide adoption of AM technologies in industry.

scholarly journals Tolerance Synthesis of Mechanisms: A Robust Design Approach

2005 ◽  
Vol 127 (1) ◽  
pp. 86-94 ◽  
Author(s):  
Ste´phane Caro ◽  
Fouad Bennis ◽  
Philippe Wenger
Keyword(s):  
Robust Design ◽  
Design Method ◽  
Synthesis Method ◽  
Second Step ◽  
Serial Manipulators ◽  
Tolerance Synthesis ◽  
General Issue ◽  
Synthesis Of Mechanisms ◽  
Performance Error ◽  
Robust Design Method

This paper provides a new robust design method to dimension a mechanism and to synthesize its dimensional tolerances. The general issue is to find a robust mechanism for a given task, and to compute its optimal dimensional tolerances. For that purpose, the developed approach follows two consecutive steps, which are independent and complementary. First, the dimensions of the mechanism are computed by means of an appropriate robustness index, which is used to minimize the sensitivity of its performances to variations. These robust dimensions are obtained independently of the amount of variations, and tolerate globally the largest variations. Thus, knowing the acceptable performance error of the mechanism, the second step aims at computing the optimal dimensional tolerances of the mechanism by means of the new tolerance synthesis method. This method is used to find the best distribution of the error between the dimensions of the mechanism. Two serial manipulators are studied to illustrate the theory.

A new single acquisition, two-image difference method for determining MR image SNR

2009 ◽  
Vol 36 (2) ◽  
pp. 662-671 ◽  
Author(s):  
Michael C. Steckner ◽  
Bo Liu ◽  
Leslie Ying
Keyword(s):  
Difference Method ◽  
Mr Image ◽  
Image Difference

scholarly journals Parametric Design and Kansei Engineering in Goblet Styling Design

2020 ◽  
Vol 2020 ◽  
pp. 1-8
Author(s):  
Fong-Gong Wu ◽  
Chii-Zen Yu
Keyword(s):  
Evaluation Method ◽  
Parametric Design ◽  
Design Method ◽  
Three Dimensional ◽  
Transformation Method ◽  
Market Demand ◽  
Kansei Engineering ◽  
Cam Mechanism ◽  
Projective Curves ◽  
Point Data

In this study, we developed a computer-aided product design method for goblet styling design based on two methods. The first was parametric design derived from an adjustable cam mechanism, which was used for shape generation, and the second was Kansei engineering, which was used for shape evaluation. In the shape generation method, motion curves from an adjustable cam were used. Designers can collect feature point data from existing products to define the boundary conditions of adjustable cam motion equations; furthermore, adjustable motion curves allow parametric design. Through adjusting a single parameter, motion curves were changed to be used as projective curves for the styling design of goblets. Then, a coordinate transformation method was applied to support the three-dimensional styling design of goblets. In the shape evaluation method, some goblet stylings were regularly selected to determine adjective degrees by production design experts. Adjective degrees for goblets that had not been selected were determined through interpolation. Market demand was defined as the preference of customers for specific adjective degrees for goblets.

Study and Application of Three-Step Supporting Design Method in Coal Roadway

2013 ◽  
Vol 353-356 ◽  
pp. 252-257
Author(s):  
Ren Liang Shan ◽  
Xiang Song Kong ◽  
Ji Jun Zhou ◽  
Wen Feng Zhao ◽  
Yu Tao ◽  
...  
Keyword(s):  
Design Method ◽  
Surrounding Rock ◽  
Second Step ◽  
Preliminary Design ◽  
The Third ◽  
Coal Roadway ◽  
Roadway Stability ◽  
Simulation Calculation ◽  
Roadway Support ◽  
The Stability

Scientific supporting design is of great significance to ensure coal roadway stability. The three-step supporting design method is put forward for coal roadway support: The first step is preliminary design, determine the range of each supporting parameter according to the theoretical calculation and supporting experiences; the second step is numerical simulation calculation, choose the reasonable one through the comparison of schemes; the third step is field monitoring, verify the scheme applicability. After applying the three-step supporting design method to study 3# coal seam roadway in Guandi mine, the optimal supporting scheme is obtained, and good results of underground roadway are achieved, which ensure the stability of roadway surrounding rock. Meanwhile, some rules are summarized which provide references for future roadway supporting design.

scholarly journals Mixed Perspectives and Thematic Analysis in Design Education

2021 ◽  
Vol 8 (4) ◽  
pp. 78-88
Author(s):  
Qinghua YU ◽  
Yukari Nagai
Keyword(s):  
Thematic Analysis ◽  
Design Education ◽  
Design Method ◽  
Emotional Experience ◽  
Online Course ◽  
Second Step ◽  
Qualitative Thematic Analysis ◽  
To Come ◽  
Design Ideas ◽  
Novel Design

This research explores the design of products based on users’ emotional requirements and how students can be stimulated to generate novel ideas in design education. In order to achieve these aims, multiple methods were taught to students during an online course. In the first step, the students utilised interviews, questionnaires, and mixed perspectives to design hill censers according to the users’ emotional requirements. In the second step, the researcher conducted a qualitative thematic analysis to study the students’ collected survey reports. The analytic results were then shared with students to help them quickly obtain better novel design ideas. And then, an emotional design appraisal model was built in the third step. The two main findings are as follows: first, creation in light of the stakeholder’s perspective enabled the students to come up with better design ideas quickly. Second, the ‘design method’ and ‘emotional experience’ themes obtained by the thematic analysis were found to be vital for the designers/students. Notably, the ‘design method’ theme can help students generate novel design ideas, and the students can learn the users’ needs from the ‘emotional experience’ theme.

scholarly journals Air-Gap Flux Oriented Vector Control Based on Reduced-Order Flux Observer for EESM

Energies ◽  
2021 ◽  
Vol 14 (18) ◽  
pp. 5874
Author(s):  
Feng Cai ◽  
Ke Li ◽  
Xiaodong Sun ◽  
Minkai Wu
Keyword(s):  
Difference Method ◽  
Motor System ◽  
Transformation Method ◽  
Torque Control ◽  
Regulation System ◽  
Bilinear Transformation ◽  
Reduced Order ◽  
Flux Observer ◽  
First Order ◽  
The Stability

Electrically excited synchronous motor (EESM) has the characteristics of high order, nonlinear and strong coupling, so it is difficult to be controlled. However, it has the advantages of adjustable power factor, high efficiency, and high precision torque control, so it is widely used in high-power applications. The accuracy of a flux observer influences the speed control system of EESM. Based on state observer in modern control theory and electrical excitation synchronous machine state equation, a reduced-order flux observer is designed. Using the first-order difference method and forward bilinear transformation method, the reduced-order flux observer is discrete, and the stability of the motor system is analyzed. The analysis shows that the stability of the system using the bilinear transformation method is better than that using the first order forward difference method. In motor operation, motor parameters will be affected by the factors of temperature, magnetic saturation, and motor frequency. In this paper, the influence of parameter variation on the motor system is studied by using the variation of the pole distribution. Finally, the speed regulation system using the reduced-order observer is simulated, which verifies the accuracy of the reduced-order flux observer observation.

scholarly journals Soil Probabilistic Slope Stability Analysis Using Stochastic Finite Difference Method

2017 ◽  
Vol 11 (4) ◽  
pp. 23 ◽  
Author(s):  
Mohamadbagher Effati Daryani ◽  
Hadi Bahadori ◽  
Khalil Effati Daryani
Keyword(s):  
Shear Strength ◽  
Stability Analysis ◽  
Finite Difference ◽  
Finite Difference Method ◽  
Slope Stability ◽  
Difference Method ◽  
Slope Failure ◽  
Design Method ◽  
Limit State ◽  
Partial Factor

The paper contrasts results obtained by the partially factored limit state design method and a more advanced Random Finite Difference Method (RFDM) in a benchmark problem of slope stability analysis with variable undrained shear strength. Local Average Subdivision method was used to simulate the non-Gaussian random variables. The key difference between the methods is that RFDM takes into account spatial variability of soil parameters allowing slope failure to occur naturally along the path of least resistance. The probabilistic method leads to predictions of the "probability of slope failure" as opposed to the more traditional "factor of safety" measure of slope safety in the limit state design method; however, they give significant different results depending on the level of the variability. Analyses conducted using Monte Carlo Simulation show that the same partial factor can have very different levels of risk depending on the degree of uncertainty of the mean value of the soil shear strength. Calibration studies show the partial factor necessary to achieve target probability values.

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