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Article: Selecting the proper material for a grain loss sensor based on DEM simulation and structure optimization to improve monitoring ability

Liang, Zhenwei

Precision agriculture. 2021 Aug., v. 22, no. 4

2021

Abstract: To improve the monitoring accuracy of grain loss sensors, an optimised structure for grain loss sensors was designed. First, stainless steel 304, copper plate and aluminum T6 were selected as potential materials for sensitive plates, and the collision ... ...

Abstract	To improve the monitoring accuracy of grain loss sensors, an optimised structure for grain loss sensors was designed. First, stainless steel 304, copper plate and aluminum T6 were selected as potential materials for sensitive plates, and the collision signal characteristics with these different materials were studied in detail. Then, the relationship between the damping ratio and collision response was studied. The detection revolution was improved significantly by integrating viscoelastic damping layers into the sensitive plate. An optimal passive vibration isolation structure was designed to reduce the effect of vibrations on collision signals. Finally, field tests were performed, and the results revealed that the relative error was ≤ 3.46%.
Keywords	aluminum ; precision agriculture ; stainless steel ; vibration ; viscoelasticity
Language	English
Dates of publication	2021-08
Size	p. 1120-1133.
Publishing place	Springer US
Document type	Article
ZDB-ID	1482656-2
ISSN	1385-2256
ISSN	1385-2256
DOI	10.1007/s11119-020-09772-w
Database	NAL-Catalogue (AGRICOLA)

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Article: Role of echogenic foci in ultrasonographic risk stratification of thyroid nodules: Echogenic focus scoring in the American College of Radiology Thyroid Imaging Reporting and Data System.

Li, Renxu / Liang, Zhenwei / Wang, Xiangyu / Chen, Luzeng

Frontiers in oncology

2022 Volume 12, Page(s) 929500

Abstract: Background: Although echogenic foci may raise malignancy rates in thyroid nodules, the association between peripheral calcification or macrocalcification and thyroid carcinoma is controversial. We evaluated the malignancy probability of various ... ...

Abstract	Background: Although echogenic foci may raise malignancy rates in thyroid nodules, the association between peripheral calcification or macrocalcification and thyroid carcinoma is controversial. We evaluated the malignancy probability of various echogenic foci and explored whether the method of determining a thyroid nodule's point score in the echogenic focus category of the American College of Radiology (ACR) Thyroid Imaging Reporting and Data System (TI-RADS) is reasonable. Methods: We retrospectively evaluated 819 patients with 852 nodules. The patterns of echogenic foci on ultrasonography were classified into the following four categories: punctate echogenic foci, macrocalcification, peripheral calcification, and multiple different types of echogenic foci. The core needle biopsy results were divided into two groups: benign and malignant or suspicious for malignancy. Results: Among the 852 nodules, 471 (55.3%) had echogenic foci on ultrasonography. Of these nodules, there was no significant statistical difference in the malignant or suspicious for malignancy rate between nodules with peripheral calcification and those with macrocalcification [40.0% (8/20) Conclusion: We found no significant statistical difference in the risk of malignancy or suspicious for malignancy rate between peripheral calcification and macrocalcification in thyroid nodules. We observed that nodules with multiple different types of echogenic foci were not associated with higher malignant or suspicious for malignancy rates compared with nodules with punctate echogenic foci alone.
Language	English
Publishing date	2022-08-29
Publishing country	Switzerland
Document type	Journal Article
ZDB-ID	2649216-7
ISSN	2234-943X
ISSN	2234-943X
DOI	10.3389/fonc.2022.929500
Database	MEDical Literature Analysis and Retrieval System OnLINE

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Article: Development of single measuring point overall balancing method based on multi-cylinder dynamic balance detection system

Yu, Zhiwu / Li, Yaoming / Liang, Zhenwei / Tang, Zhong

Computers and electronics in agriculture. 2022 Apr. 10,

2022

Abstract: The combine harvester with multi-cylinder has a wide application in improving the operation efficiency. Therefore, as an important process in combine harvester, threshing operated by multi-cylinder usually makes the working structures suffer hit from the ...

Abstract	The combine harvester with multi-cylinder has a wide application in improving the operation efficiency. Therefore, as an important process in combine harvester, threshing operated by multi-cylinder usually makes the working structures suffer hit from the blockage of stones or materials. Consequently, the cylinders fail to guarantee the original balance. Several studies have been performed in this area, based on the dynamic balance method and vibration signal processing. However, most of them are not efficient for multi-cylinder. This study aims at developing an online dynamic balance detection system for multi-cylinder in combine harvester, in order to enhance the efficiency and accuracy of online dynamic balance detection. A multi-cylinder test rig is developed, and unbalanced vibration experiments under different working conditions are performed. The results show that the different measuring positions have different sensitivities to unbalanced mass. The vibrations will be transmitted through the frame, and coupled with each other. Under the multi-cylinder rotation, the vibration has strong randomness and poor convergence. For this purpose, the single measuring point overall balancing method is proposed. An adaptive multiple filter algorithm relying on the LabVIEW platform, is also proposed. Through phase relation between cylinders, the single measuring point overall balancing algorithm is developed. The comparison experimental results show that the proposed algorithm is more robust under the multi-cylinder rotation. The proposed method simultaneously installs sensors on the bearing seat of No. 1 tangential cylinder and balance 3 cylinders. The traditional method balance 3 cylinders separately change the sensor position. The effect of the proposed method is almost 76%, while that of the traditional balance method is almost 66%. For the multi-cylinder system, the single measuring point overall balancing method can efficiently improve the balance effect by 10%. Finally, it can be deduced from the experiment on the combine harvester that the accuracy of the proposed method reaches G3.9.
Keywords	agriculture ; algorithms ; combine harvesters ; electronics ; vibration
Language	English
Dates of publication	2022-0410
Publishing place	Elsevier B.V.
Document type	Article
Note	Pre-press version
ZDB-ID	395514-x
ISSN	0168-1699
ISSN	0168-1699
DOI	10.1016/j.compag.2022.106968
Database	NAL-Catalogue (AGRICOLA)

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Article ; Online: Wheat Lodging Direction Detection for Combine Harvesters Based on Improved K-Means and Bag of Visual Words

Zhang, Qian / Chen, Qingshan / Xu, Lizhang / Xu, Xiangqian / Liang, Zhenwei

Agronomy. 2023 Aug. 25, v. 13, no. 9

2023

Abstract: For the inconsistent lodging of wheat with dense growth and overlapped organs, it is difficult to detect lodging direction accurately and quickly using vehicle vision for harvesters. Therefore, in this paper, the k-means algorithm is improved by ... ...

Abstract	For the inconsistent lodging of wheat with dense growth and overlapped organs, it is difficult to detect lodging direction accurately and quickly using vehicle vision for harvesters. Therefore, in this paper, the k-means algorithm is improved by designing a validity evaluation function, selecting initial clustering centers by distance, constructing a multidimensional feature vector, and simplifying calculations using triangle inequality. An adaptive image grid division method based on perspective mapping and inverse perspective mapping with a corrected basic equation is proposed for constructing a dataset of wheat lodging directions. The improved k-means algorithm and direction dataset are used to construct a bag of visual words. Based on scale-invariant feature transform, pyramid word frequency, histogram intersection kernel, and support vector machine, the wheat lodging directions were detected in the grid. The proposed method was verified through experiments with images acquired on an intelligent combine harvester. Compared with single-level word frequencies with existing and improved k-means, the mean accuracy of wheat lodging direction detection by pyramid word frequencies with improved k-means increased by 6.71% and 1.11%, respectively. The average time of detection using the proposed method was 1.16 s. The proposed method can accurately and rapidly detect wheat lodging direction for combine harvesters and further realize closed-loop control of intelligent harvesting operations.
Keywords	agronomy ; combine harvesters ; data collection ; equations ; support vector machines ; vision ; wheat
Language	English
Dates of publication	2023-0825
Publishing place	Multidisciplinary Digital Publishing Institute
Document type	Article ; Online
ZDB-ID	2607043-1
ISSN	2073-4395
ISSN	2073-4395
DOI	10.3390/agronomy13092227
Database	NAL-Catalogue (AGRICOLA)

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Article ; Online: Rice grains and grain impurity segmentation method based on a deep learning algorithm-NAM-EfficientNetv2

Liu, Qinghua / Liu, Weikang / Liu, Yishan / Zhe, Tiantian / Ding, Bochuan / Liang, Zhenwei

Computers and Electronics in Agriculture. 2023 June, v. 209 p.107824-

2023

Abstract: An appropriate image segmentation algorithm is required for discriminating between full grains and grain impurities. In this study, a lightweight fully convolutional segmentation algorithm based on NAM EfficientNetV2 was proposed to solve the problem of ... ...

Abstract	An appropriate image segmentation algorithm is required for discriminating between full grains and grain impurities. In this study, a lightweight fully convolutional segmentation algorithm based on NAM EfficientNetV2 was proposed to solve the problem of slow processing speed in mobile terminal equipment owing to limited computing resources and a large number of model parameters and improve the detection accuracy. First, a standardized NAM attention mechanism was introduced to replace the SE attention mechanism used in EfficientNetV2 and the improved NAM-EfficientNetV2 network was used as a feature extraction structure. Then, in the up-sampling process, the multi-scale features output by the shallow network are fused to effectively use low-level semantics to encode spatial details and fully convolutional pixel segmentation technology is used to achieve rice grain and impurity segmentation. Finally, compared with the baseline model, the detection accuracy of the model was further improved on a self-made dataset. The comprehensive evaluation index F1 of rice grain and its impurities were 95.26% and 93.27%, respectively, and the model parameter amount was 20.6 M. Combined with post-processing, detecting an image on the GPU device took an average of 0.103 s and 0.301 s on the CPU device. The experimental results showed that the improved algorithm is more lightweight, which provides a reference for the model to be deployed in mobile terminal equipment to realize the function of real-time detection of grain impurity in the combine harvester.
Keywords	agriculture ; algorithms ; combine harvesters ; data collection ; electronics ; image analysis ; models ; rice
Language	English
Dates of publication	2023-06
Publishing place	Elsevier B.V.
Document type	Article ; Online
ZDB-ID	395514-x
ISSN	0168-1699
ISSN	0168-1699
DOI	10.1016/j.compag.2023.107824
Database	NAL-Catalogue (AGRICOLA)

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Article ; Online: Ultrasound and clinical factors predicting central lymph node metastases in patients with unilateral multifocal papillary thyroid carcinoma.

Liang, Zhenwei / Zhang, Jixin / Chen, Lei / Liu, Jinghua / Wang, Fumin / Shao, Yuhong / Sun, Xiuming / Chen, Luzeng

Asia-Pacific journal of clinical oncology

2024

Abstract: Objective: This retrospective study involving a large dataset of unilateral multifocal papillary thyroid carcinoma (UM-PTC) sought to identify factors that predict central lymph node metastases (CLNM) in patients.: Methods: We identified a cohort of ... ...

Abstract	Objective: This retrospective study involving a large dataset of unilateral multifocal papillary thyroid carcinoma (UM-PTC) sought to identify factors that predict central lymph node metastases (CLNM) in patients. Methods: We identified a cohort of 158 patients who underwent cervical ultrasonography followed by UM-PTC diagnosis based on postoperative pathology. The relationship between CLNM and UM-PTC clinical ultrasound features was evaluated using univariate and multivariate analyses. Receiver operating characteristic (ROC) curve analysis was used to determine the ability of total tumor diameter (TTD) to predict CLNM. Results: Among the 158 UM-PTC patients, the incidence of CLNM was 29.7% (47/158). Univariate and multivariate analyses revealed that a number of similarity of sonographic features (NSSF) ≥4 (odds ratio [OR] = 11.335, 95% confidence interval [CI]: 3.95-32.50, p = 0.000), microcalcifications (OR = 3.54, 95% CI: 1.30-9.70, p = 0.014), a TTD of ≥2 cm (OR = 4.48, 95% CI: 1.62-12.34, p = 0.004), number of nodules ≥3 (OR = 13.17, 95% CI: 3.24-53.52, p = 0.000), and Lateral cervical lymph node metastasis (LLNM) (OR = 5.57, 95% CI: 1.59-19.48, p = 0.007) were independently associated with CLNM in UM-PTC. ROC curve analysis revealed that the TTD cut-off of 1.795 cm had a sensitivity of 0.723 and a specificity of 0.676 for predicting CLNM. Conclusions: Patients with UM-PTC are at high risk of CLNM. NSSF ≥4, microcalcifications, TTD of ≥2 cm, LLNM, and a number of nodules ≥3 were independently associated with CLNM. Our data show that ultrasound may guide surgical decisions in the treatment of UM-PTC.
Language	English
Publishing date	2024-04-24
Publishing country	Australia
Document type	Journal Article
ZDB-ID	2187409-8
ISSN	1743-7563 ; 1743-7555
ISSN (online)	1743-7563
ISSN	1743-7555
DOI	10.1111/ajco.14070
Database	MEDical Literature Analysis and Retrieval System OnLINE

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Article: Precision Phenotypic Profiling and Capture of Circulating Tumor Cells via a Vertical Laminar Flow-Stacked Microfluidic Chip.

Zhang, Xinping / Ma, Yuan / Wang, Yujiao / Liang, Zhenwei / Zhang, Xuanhe / Chen, Yiqing / Wang, Qingyi / Qin, Hua / Wang, Jiadao

Micromachines

2024 Volume 15, Issue 4

Abstract: The heterogeneity of circulating tumor cells has a significant impact on the diagnosis, treatment, and monitoring of cancer. Research on the subtypes of circulating tumor cells can bring better treatment outcomes for cancer patients. Here, we proposed a ... ...

Abstract	The heterogeneity of circulating tumor cells has a significant impact on the diagnosis, treatment, and monitoring of cancer. Research on the subtypes of circulating tumor cells can bring better treatment outcomes for cancer patients. Here, we proposed a microfluidic chip for the magnetic capture of subtypes of circulating tumor cells from the whole blood and phenotypic profiling by stacking laminar flow vertically. Circulating tumor cells were sorted and captured by the three-dimensional regulation of both magnetic fields in the vertical direction and flow fields in the lateral direction. Using EpCAM-magnetic beads, we achieved sorting and sectional capture of target cells in whole blood and analyzed the surface expression levels of the captured cells, confirming the functionality of the microfluidic chip in sorting and capturing subtypes of circulating tumor cells. This microfluidic chip can also aid in the subsequent subtype analysis of other rare cells.
Language	English
Publishing date	2024-04-18
Publishing country	Switzerland
Document type	Journal Article
ZDB-ID	2620864-7
ISSN	2072-666X
ISSN	2072-666X
DOI	10.3390/mi15040542
Database	MEDical Literature Analysis and Retrieval System OnLINE

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Article: Analyzing Rice Grain Collision Behavior and Monitoring Mathematical Model Development for Grain Loss Sensors

Li, Depeng / Wang, Zhiming / Liang, Zhenwei / Zhu, Fangyu / Xu, Tingbo / Cui, Xinyang / Zhao, Peigen

Agriculture (Basel). 2022 June 10, v. 12, no. 6

2022

Abstract: Grain loss in the harvesting process of combine harvesters not only causes economic losses to farmers but also affects the soil environment because of the lost grain covering the soil, influencing crop growth in the next season. Grain sieve loss- ... ...

Abstract	Grain loss in the harvesting process of combine harvesters not only causes economic losses to farmers but also affects the soil environment because of the lost grain covering the soil, influencing crop growth in the next season. Grain sieve loss-monitoring sensors represent an important accessory in combine harvesters, as they can not only provide current grain loss levels for the operator to adopt a rational action in time but also serve as an important performance signal for the control system. To reflect the rice grain sieve loss level of combine harvesters in real time, an indirect grain sieve loss-monitoring system is proposed in this paper. First, the grain collision rise time was obtained by the finite element method (FEM), and the parameters of the grain loss sensor signal processing circuit were determined accordingly to upgrade the monitoring accuracy. Then, grain loss distribution behind the cleaning shoe was analyzed in detail under different working parameters. Grain loss distribution functions at the end of the sieve and a monitoring mathematical model with relevant variables were established based on the laboratory experiment results. Finally, calibration experiments were carried out to verify the measurement accuracy of the sensor on a cleaning test bench, with an obtained relative monitoring error ≤6.41 % under different working conditions.
Keywords	agriculture ; calibration ; edaphic factors ; finite element analysis ; laboratory experimentation ; mathematical models ; rice ; soil
Language	English
Dates of publication	2022-0610
Publishing place	Multidisciplinary Digital Publishing Institute
Document type	Article
ZDB-ID	2651678-0
ISSN	2077-0472
ISSN	2077-0472
DOI	10.3390/agriculture12060839
Database	NAL-Catalogue (AGRICOLA)

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Article: Investigation into Experimental and DEM Simulation of Guide Blade Optimum Arrangement in Multi-Rotor Combine Harvesters

Liang, Zhenwei / Li, Jun / Liang, Jianmin / Shao, Yifan / Zhou, Tengfei / Si, Zengyong / Li, Yaoming

Agriculture (Basel). 2022 Mar. 21, v. 12, no. 3

2022

Abstract: The cleaning performance of the cleaning shoe of a multi-rotor combine harvester has proven to be poor owing to the threshed output entering the cleaning section in an uneven manner. Experimental results indicated that the arrangement of the guide blades ...

Abstract	The cleaning performance of the cleaning shoe of a multi-rotor combine harvester has proven to be poor owing to the threshed output entering the cleaning section in an uneven manner. Experimental results indicated that the arrangement of the guide blades on the return plate surface has a significant effect on the threshed output distribution. In this paper, DEM (discrete element method) simulations were carried out in the EDEM software to examine the effect of the height of the guide blade, the installation angle, and the number of guide blades on threshed output distribution before entering the cleaning shoe. Based on the simulated results under different guide blades arrangements, the optimum arrangement location was obtained. The simulation’s results were verified by a field experiment and were consistent with the experimental results. The field experiment results indicate that the cleaning performance significantly improved with the proper guide blade arrangement. The corresponding grain impurity ratio declined significantly from 1.26% to 0.67%, and the grain sieve loss ratio, with a decrease of 53.2%, was reduced from 1.11% to 0.52%.
Keywords	agriculture ; combine harvesters ; computer software ; field experimentation
Language	English
Dates of publication	2022-0321
Publishing place	Multidisciplinary Digital Publishing Institute
Document type	Article
ZDB-ID	2651678-0
ISSN	2077-0472
ISSN	2077-0472
DOI	10.3390/agriculture12030435
Database	NAL-Catalogue (AGRICOLA)

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Article: Improving Cleaning Performance of Rice Combine Harvesters by DEM–CFD Coupling Technology

Ding, Bochuan / Liang, Zhenwei / Qi, Yongqi / Ye, Zhikang / Zhou, Jiahao

Agriculture (Basel). 2022 Sept. 13, v. 12, no. 9

2022

Abstract: The cleaning device is an important part of combine harvesters, as its superior or inferior performance directly affects the performance of the combine harvester greatly. With an increasing rice yield, the current single-duct cleaning performance ... ...

Abstract	The cleaning device is an important part of combine harvesters, as its superior or inferior performance directly affects the performance of the combine harvester greatly. With an increasing rice yield, the current single-duct cleaning performance declines greatly, and causes a large grain sieve loss level and a direct grain loss for the farms. To optimize the existing single-duct cleaning device to meet the large feeding rate requirement, firstly, the terminal velocity of rice grain and MOG (material other than grain) for different varieties was experimentally measured by the custom-made device. The effects of the moisture content of rice grains and the length of short straws on terminal velocity were studied in detail. Then, the gas–solid two-phase flow theory was comprehensively applied by utilizing the discrete element method (DEM) and computational fluid dynamics (CFD) to study the working mechanism of the existing single-duct cleaning unit, and the cleaning performance was evaluated from the view of the motion law of the threshing output within the cleaning shoe. At last, a multi-duct cleaning device was put forward, and a field experiment was performed to assess the performance of the newly developed cleaning device. The results showed that the grain sieve losses ratio and grain impurity ratio improved dramatically, proving that structure optimization of the cleaning device was feasible.
Keywords	agriculture ; combine harvesters ; field experimentation ; fluid mechanics ; rice ; terminal velocity ; water content
Language	English
Dates of publication	2022-0913
Publishing place	Multidisciplinary Digital Publishing Institute
Document type	Article
ZDB-ID	2651678-0
ISSN	2077-0472
ISSN	2077-0472
DOI	10.3390/agriculture12091457
Database	NAL-Catalogue (AGRICOLA)

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