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Target assignment is the core part in the command and control process, and the optimization of the allocation mode is of great significance for improving the air defense and anti-missile combat capability. In order to improve the robustness, applicability, game antagonism and other combat performance of air defense and anti-missile target allocation, so as to cope with the current complex and changeable battlefield environment, this paper proposes the target allocation architecture establishment of multi-mode fusion, and adaptively improve the commercial order-type service mode. The improvement of three kinds of dispatching models, that are “dispatching order” “grabbing order” and “dispatching- grabbing order fusion”, are defined as military models. By using the US department of defense architecture framework (DoDAF) to establish a new target allocation architecture of “other allocation” “self-allocation”and “combination of other allocation and self-allocation”. With the introduction of Perti net model, the reachable map of Petri net model is constructed and analyzed. Through the simulation experiment platform, the complex combat scenario is constructed to verify the feasibility of the distribution strategy mechanism. The results show that each of the three strategies has its own advantages. The multi-strategy combination designed in this paper has greater advantages than the traditional single strategy in matching time, success rate and utility value.

Target assignment is the core of command and control decision-making stage. Many scholars have done a lot of research on target assignment problem, and made great progress in target assignment model and algorithm. However, with the evolution and development of new combat styles such as Mosaic warfare, distributed warfare and network-centric warfare, the complexity of modern air defense operations has increased unprecedentedly. In view of the problems of air defense and anti-missile tactical target assignment, such as weak adaptability to different combat scenarios, lack of game antagonism and robustness, etc., by summarizing and sorting out the research status of target assignment, the challenges faced by the theoretical research of target assignment in the application process of air defense and anti-missile operations are deeply discussed from the perspective of the development of offensive and defense systems. This paper answers the root causes of many problems in the tactical target allocation of air defense and missile defense, and puts forward the development needs of intelligent, networked and real combat target allocation in view of the deficiencies.

3D object detection is a new research direction in recent years, and its main task is the location and recognization of targets in space. The existing methods for 3D object detection using monocular or binocular stereo vision are easily affected by object occlusion, viewpoint changing and scale changing in 3D scene, there will be problems such as poor detection accuracy and robustness. LiDAR point cloud can provide 3D scene information, so using deep learning method to complete 3D object detection based on LiDAR point cloud has become a research hotspot in the field of 3D vision. Aiming at the 3D object detection based on LiDAR point cloud, the relevant research in recent years is reviewed. Firstly, the 3D object detection methods based on LiDAR point cloud are divided into point cloud based, point cloud projection based, point cloud voxelization based and multi-modal fusion based 3D object detection methods according to the data form of network input, and the most representative methods in each category are described in detail. Then common datasets are introduced, and the performance of representative methods is evaluated, and the advantages and limitations of each method are discussed from several aspects. Finally, the shortcomings and difficulties are given, and the future development directions are also discussed and put forward.

ObjectiveTo investigate the resistance to beta-cypermethrin in Aedes albopictus in Xuhui District， Shanghai， China， and determine the effects of insecticide components， concentration and distance on eliminating resistant population of Aedes albopictus in ultra-low volume （ULV） spray， which would provide scientific evidence for effective mosquito control strategy and rational use of beta-cypermethrin.MethodsLarval impregnation method recommended by the World Health Organization was used to determine the drug resistance in Aedes albopictus larvae to calculate the median lethal concentration （LC50） of insecticides to Aedes albopictus larvae. The resistance to insecticides in female adults of Aedes albopictus was measured by the adult mosquito contact tube method recommended by the World Health Organization， and the 24-hour mortality （%） of female mosquitoes caused by insecticides was measured. Then the 24-hour mortality （%） of resistant female adults of Aedes albopictus due to beta cypermethrin monotherapy and compound agents was calculated by ULV spray.ResultIn 2016， 2017， 2019 and 2021， the resistance ratio in Aedes albopictus larvae to beta-cypermethrin was 9.22， 68.22， 37.33 and 59.22， respectively. In 2021， the 24-hour mortality of Aedes albopictus female adults was 62.07%. ULV sprayer experiments were performed using 4.5% beta-cypermethrin （single dose） and 12.0% beta-cypermethrin-chlorpyrifos （compound dose）. The 24-hour mortality increased with the concentration of the insecticides. The overall mortality caused by compound was higher than that by single dose. The mortality were 24.24%， 31.60% and 97.83% at the concentrations of 0.045 0%， 0.067 5% and 0.090 0% for single dose， respectively， and 58.87%， 61.62% and 90.00% at the concentrations of 0.12%， 0.18% and 0.24% for compound dose， respectively. There was no significant difference in mortality when spraying distance was 10 m， 30 m and 50 m.ConclusionAedes albopictus in Xuhui District is developed varying resistance to beta-cypermethrin. It warrants to strengthen the monitoring on insecticide resistance to formulate scientific and reasonable strategy for insecticide use. and reduce the resistance level of the Aedes albopictus to beta-cypermethrin. Compound dose is recommended to improve the effect. In addition， comprehensive treatment may be adopted to reduce the resistance.

Aiming at the functional requirements of mobile mechanisms with multiple modes，a design scheme based on single-loop kinematic chains is proposed.Firstly，according to the single-loop freedom formula，the conditions satisfying the single-loop and can be active are determined，and the combination relationships among the order of the constrained screw system，the number of bars，the number of kinematic pairs and the degree of freedom of the single-loop kinematic chains are obtained.Secondly，based on the screw theory，the geometric conditions of the axis of kinematic pairs under different constrained screw orders are obtained by using the virtual work principle.Taking the R and P pairs as the design units，all the possible combinations of the single-loop kinematic chains under different degrees of freedom are enumerated，and then the constructed single-loop kinematic chains are used as the body or branch to construct a kind of mobile mechanisms with multiple modes.Finally，the steps of type synthesis of mobile mechanisms with multiple modes and some design cases are given，which verifies the feasibility and practicability of the proposed design theory and design method.

In order to reduce the interference of noise in laser Doppler vibration signal, a laser Doppler vibration signal processing method based on improved wavelet de-noising was proposed. The scale was introduced into the threshold function' and a new evaluation index was established to select the optimal decomposition level. The improved algorithm was used to process the vibration signal. The improved algorithm and the original algorithm were adopted for processing the vibration signal. The simulation analysis and experimental verification were then carried out, and the vibration data before and after processing were obtained. The results indicate that the signal-to-noise ratio of simulated signals processed by the improved algorithm is 19.4% higher than that of the original soft and hard threshold algorithm. The measured tuning fork vibration frequency is 515Hz, which is consistent with the actual tuning fork frequency. This result is helpful to reduce the influence of noise in the laser Doppler vibration signal and obtain the vibration state. [ABSTRACT FROM AUTHOR]

Objective To investigate the effect of auricular acupoint pressing therapy on cancer-related fatigue (CRF) and quality of life (QOL) in breast cancer patients with postoperative chemotherapy. Methods Totally 72 breast cancer patients undergoing chemotherapy were divided into the study group (n = 36) and the control group (n = 36). Patients in the control group only received routine cure# and those in the study group received regular auricular acupoint pressing lasting for 3 months in addition. Brief Fatigue Inventory (BFI) and Asseesment of Cancer Therapy-Breast (FACT-B) were used to evaluated their fatigue and QOL in the pre-chemotherapy, first, second' third, and fourth course of chemotherapy. Results Repeated measures analysis of variance showed that the interaction effect, group reflect and main reflect of time were statistic any significant in the score of CRF and QOL (P < 0.05). Conclusion Auricular acupoint pressing therapy can reduce the degree of CRF and improve QOL of patients with breast cancer undergoing postoperative chemotherapy. [ABSTRACT FROM AUTHOR]

A bionic multi-mode moving mechanism was designed, which can realize the sliding, crawling and rolling sports modes. Based on the principle of bionics, the four-legged walking, flapping wing, and circular rolling creatures were used as bionic objects to abstract the motion structural unit equivalent to the bionic object. Through the screw theory of configuration design analysis, combined with the spatial geometric symmetry principle and the variable degree of freedom idea, the two equivalent unit bodies were symmetrically arranged to form a multi-mode mobile mechanism. The simulation results showed that the mechanism could achieve the expected motion mode, reasonable design, good stability and maneuverability. [ABSTRACT FROM AUTHOR]

A controller for vehicle electronic stability program (ESP) based on direct yaw-moment control (DYC) strategy is designed with nonlinear H∞ feedback control adopted as DYC algorithm. A nonlinear observer is built for accurately estimating the longitudinal and lateral velocities of vehicle. An actuator allocation module is also designed to distribute actuator resources for all sub-controllers to prevent conflict in operation between DYC and ABS or ASR systems and ensuring the normal execution of multi-functions of ESP. An ESP controller is autonomously developed based on processor ARM7 and a platform for hardware-in-the-loop (HIL) test is constructed. The results of HIL test verify the effectiveness of the control strategy. [ABSTRACT FROM AUTHOR]

The traditional vulnerability assessment of water inrush from coal seam floor often obtains the constant weight of each influence factor through different models and calculation methods.When evaluating, each subarea adopts this fixed weight, ignoring the fact that the index values of each influence factor in different subareas are in different combinations, and the influence weight should be adjusted accordingly to reflect the relative importance of each influence factor in water inrush from coal seam floor in real time.In this paper, combined with the constant weights of the influence factors determined by AHP, the zoning variable weight model is introduced to adjust the weight distribution of different zones under different combinations of factors, which improves the irrationality of constant weights in different zoning evaluation, further improves the accuracy of evaluation results, and provides some reference for the safe production of coal mines.

Objective: To explore the diagnostic value of American Society of Radiology Thyroid Imaging Reporting and Data System（ACR-TIRADS） and Chinese Thyroid Nodule Ultrasound Malignant Risk Stratification（C-TIRADS） in nodular Hashimoto thyroiditis and papillary thyroid carcinoma with Hashimoto thyroiditis. Methods: This retrospective analysis included 144 patients（204 thyroid nodules） accompanied by nodular Hashimoto thyroiditis or papillary thyroid carcinoma under the background of Hashimoto thyroiditis confirmed by surgical pathology examination in the First Affiliated Hospital of Hebei North University from August 2018 to May 2021, all nodules were examined by ultrasound, and 204 nodules were scored and graded according to the classification standards of ACR-TIRADS and C-TIRADS. The surgical pathological results were the gold standard. The receiver operating characteristic curve of ACR-TIRADS and C-TIRADS was constructed to evaluate and compare the diagnostic performance of the two guideline. Results: ①Ultrasound feature results showed that nodular Hashimoto thyroiditis and Papillary thyroid carcinoma had statistically significant differences in the location, echogenicity, calcifications and margins（ P <0.001）, but there is no significant difference in structure and aspect ratio between the two kinds of nodular（ P =0.141, P =0.240）; nodular Hashimoto thyroiditis were mostly absent focal echogenicity and hyperechogenicity, while papillary thyroid carcinoma was mostly manifested as focal echogenicity and extrinsic thyroid invasion. ②The sensitivity and negative predictive value of C-TIRADS were 91.7% and 83.1%, respectively, which were higher than those of ACR-TIRADS, and the difference was statistically significant（ P =0.021, P =0.013）; The specificity and positive predictive value of C-TIRADS T were 98.3% and 99.2%, both of which were slightly higher than ACR-TIRADS, althought the difference was not statistically significant（ P =0.157, P =0.062）. The area under the curve of the ACR-TIRADS and C-TIRADS were 0.806 and 0.941, respectively, and the difference was statistically significant（ P =0.031）. ③The unnecessary FNAB rate of C-TIRADS was 10.3%, which was lower than ACR-TIRADS. Conclusion: C-TI-RADS has a better diagnostic value of nodular Hashimoto thyroiditis and thyroid papillary carcinoma under the background of Hashimoto thyroiditis, which is helpful for clinical evaluation of such nodules., Competing Interests: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose., (Copyright© by the Editorial Department of Journal of Clinical Otorhinolaryngology Head and Neck Surgery.)

Objective: To prepare a bone tissue engineering scaffold for repairing the skull defect of Sprague Dawley (SD) rats by combining exogenous transforming growth factor β 1 (TGF-β 1 ) with gelatin methacryloyl (GelMA) hydrogel., Methods: Firstly, GelMA hydrogel composite scaffolds containing exogenous TGF-β 1 at concentrations of 0, 150, 300, 600, 900, and 1 200 ng/mL (set to groups A, B, C, D, E, and F, respectively) were prepared. Cell counting kit 8 (CCK-8) method was used to detect the effect of composite scaffold on the proliferation of bone marrow mesenchymal stem cells (BMSCs) in SD rats. ALP staining, alizarin red staining, osteocalcin (OCN) immunofluorescence staining, and Western blot were used to explore the effect of scaffolds on osteogenic differentiation of BMSCs, and the optimal concentration of TGF-β 1 /GelMA scaffold was selected. Thirty-six 8-week-old SD rats were taken to prepare a 5 mm diameter skull bone defect model and randomly divided into 3 groups, namely the control group, the GelMA group, and the GelMA+TGF-β 1 group (using the optimal concentration of TGF-β 1 /GelMA scaffold). The rats were sacrificed at 4 and 8 weeks after operation, and micro-CT, HE staining, and OCN immunohistochemistry staining were performed to observe the repair effect of skull defects., Results: The CCK-8 method showed that the TGF-β 1 /GelMA scaffolds in each group had a promoting effect on the proliferation of BMSCs. Group D had the strongest effect, and the cell activity was significantly higher than that of the other groups ( P <0.05). The results of ALP staining, alizarin red staining, OCN immunofluorescence staining, and Western blot showed that the percentage of ALP positive area, the percentage of alizarin red positive area, and the relative expressions of ALP and OCN proteins in group D were significantly higher than those of the other groups ( P <0.05), the osteogenesis effect in group D was the strongest. Therefore, in vitro experiments screened out the optimal concentration of TGF-β 1 /GelMA scaffold to be 600 ng/mL. Micro-CT, HE staining, and OCN immunohistochemistry staining of rat skull defect repair experiments showed that the new bone tissue and bone volume/tissue volume ratio in the TGF-β 1 +GelMA group were significantly higher than those in the GelMA group and control group at 4 and 8 weeks after operation ( P <0.05)., Conclusion: The TGF-β 1 /GelMA scaffold with a concentration of 600 ng/mL can significantly promote the osteogenic differentiation of BMSCs, can significantly promote bone regeneration at the skull defect, and can be used as a bioactive material for bone tissue regeneration.

Objective: To investigate the value of combination of thyroid imaging reporting and data system (TI-RADS) and enhanced flow (e-Flow) in the qualitative diagnosis of thyroid nodules; and to compare the diagnostic efficiency between e-Flow and color doppler flow imaging (CDFI., Method: The study chose 133 patients with 179 nodules (127 benign, 52 malignant nodules) who had per-operative ultrasound examination of their thyroid using grey-scale ultrasound, CDFI, e-Flow, and their noudles were graded by TI-RADS. Then the ultrasound diagnostic value were compared with their surgical pathology results by TI-RADS; TI-RADS and CDFI; TI-RADS and e-Flow, and diagnostic efficiency between e-Flow and CDFI were compared., Result: The results revealed that combination of TI-RADS and e-Flow had a higher sensitivity (94.23%, P < 0.05). There was no statistically significant difference between TI-RADS and the combination of TI-RADS and CDFI. Likewise, there was no significant difference between the combination of TI-RADS and e-Flow and the combination of TI-RADS and CDFI. The e-Flow showed a higher sensitivity, specificity and accuracy compare to the CDFI., Conclusion: Combining e-Flow and TI-RADS could improve the sensitivity in qualitative diagnosis of thyroid nodules. Also, e-Flow has a better diagnostic efficiency of thyroid nodules.