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Farmland boundary data, an important basic data for the operation of agricultural automation equipment, has been widely studied by scholars from all over the world. However, the common methods of farmland boundary acquisition through sensors such as LiDAR and vision cameras combined with complex algorithms suffer from problems such as serious data drift, difficulty in eliminating noise, and inaccurate plot boundary data. In order to solve this problem, this study proposes a method for estimating the orientation dimensions of farmland based on the seeding trajectory. The method firstly calculates the curvature of the discrete data of the seeding trajectory; secondly, we innovatively use a low-pass filter and integral clustering to filter the curvature values and distinguish between straight lines and curves; and finally, the straight-line portion located at the edge of the seeding trajectory is fitted with a univariate linear fit to calculate the estimation of the farmland size orientation. As verified by the field experiments, the minimum linear error of the vertices is only 0.12m, the average error is 0.315m, and the overlapping rate of the plot estimation is 98.36% compared with the real boundary of the plot. Compared with LiDAR mapping, the average linear error of the vertices' position is reduced by 50.2%, and the plot estimation overlap rate is increased by 2.21%. The experimental results show that this method has the advantage of high accuracy, fast calculation speed, and small calculation volume, which provides a simple and accurate method for constructing farmland maps, provides the digital data support for the operation of agricultural automation equipment, and has significance for farm digital mapping. [ABSTRACT FROM AUTHOR]

The maximum radial size of the conventional three-bit four-way electromagnetic cartridge valve is greater than the largest containable size of the fluid control valve used for downhole robots. This paper proposes two kinds of solutions to reduce the radial dimension of the three-bit four-way electromagnetic insertion valve: one is to reduce the radial arrangement of the coil and increase the axial arrangement of the coil, and the other is to reduce the diameter of the moving iron core to reduce the winding radius of the coil. Using the theoretical model established in the following text, a simulation experiment was conducted. The results show that the movement of the valve spool is basically completed within 30 ms. Then, a matching experiment on the electromagnetic insertion valve was designed and conducted. The experimental results show that the opening time of the solenoid valve on the left coil is about 52 ms, and the opening time of the solenoid valve on the right coil is about 44 ms. The reaction time of the valve spool is suitable for the practical application of the solenoid valve. The significance of this paper is the reduced radial size of the three-bit four-way electromagnetic insertion valve. These improvements have reduced the size of downhole drilling robots, which facilitates the application of downhole drilling robots in narrower environments. [ABSTRACT FROM AUTHOR]

Primary primitive neuroectodermal tumor (PNET) in the female tract is rare. Recently, a case of cervical PNET was diagnosed in our hospital. A 29-year-old pregnant woman presented with a cystic-solid cervical mass at the 7th week of gestation. The mass grew rapidly during follow-up and ruptured at the 22nd week. A biopsy was performed on the mass. Pathological examination revealed a malignant neoplasm composed of small cells which exhibited positive immunohistochemical (IHC) staining for CD99, SYN, and FLI1. Fluorescence in situ hybridization (FISH) displayed the presence of EWS-FLI1 fusion gene resulting from the chromosomal translocation t (11;22, q24;q12), which confirmed the diagnosis of cervical PNET. The reverse transcription-polymerase chain reaction (RT-PCR) results showed type 2 EWS-FLI1 fusion occurred in this tumor, suggesting a poor prognosis. The patient underwent surgical resection and was given adjuvant chemotherapy followed by pelvic radiotherapy. PNET arising from the genital tract, especially in the uterine cervix, is very rare and presents a diagnostic challenge. FISH and RT-PCR analysis are helpful for the diagnosis of such a tumor at an unusual site, as in the present case.