The IR Characteristics Modeling and Simulation of the HEO Target

Space target infrared (IR) characteristics model can be used to design space target detection sensor, generating simulation data to validate the data processing algorithms, such as target detection and tracking. In the work, a HEO target IR characteristics model is built. The model consists of the geometry module and the IR radiometric module. Unlike the traditional space IR model, the temperature of cabin inner is used as the simulation origin. Using the model, the irradiance spectra of HEO target are calculated for different target temperature. With the calculation results, the main wavelength range for HEO detection is analyzed. Using the equvalent temperature, the work also designs a simulative target, which has the similar IR characteristics of a HEO target. The simulator can be used in the ground test for the imaging sensor or target decoy

Mass Transfer Theory Based Analysis of Influencing Factors on Component Gradient of Near-surface Atmosphere on Venus

The atmosphere of Venus differs completely from that of Earth despite the planets’ similarity in size and mass. At Venus's surface, the atmosphere is hot and dense, with a temperature of approximately 735 K and a pressure of approximately 92 bar. The temperature profile from the Soviet VeGa-2 probe shows high instability of the near-ground potential temperature, which, according to relevant research, can be explained by the vertical gradient of N _2 mole fraction. Based on the Maxwell–Stefan mass transfer theory, we propose a theoretical model of binary gas component for a quantitative discussion of influencing factors for the N _2 vertical concentration gradient, which consist of temperature, gravity, specific heat ratio, mass relative factor, thermal diffusion factor, and CO _2 flux. Our model shows that the 0%–3.5% N _2 concentration gradient cannot be generated without CO _2 flux in the near-ground atmosphere of Venus. And the result with CO _2 source indicates that the 0.000001%–3.5% N _2 concentration gradient at 0–7 km atmosphere can be generated by the 2.7 × 10 ^−6 mol m ^−2 s ^−6 CO _2 flux on Venusian surface, which is in agreement of gradient reckoned by VeGa-2's data. This magnitude of CO _2 flux is close to the one produced by volcanic eruptions on Earth, indicating possible existence of volcanic activities on the surface of Venus. This work has provided the community a new vision to understand the influencing factors of Venusian atmospheres composition distribution

The IR Characteristics Modeling and Simulation of the HEO Target

Space target infrared (IR) characteristics model can be used to design space target detection sensor, generating simulation data to validate the data processing algorithms, such as target detection and tracking. In the work, a HEO target IR characteristics model is built. The model consists of the geometry module and the IR radiometric module. Unlike the traditional space IR model, the temperature of cabin inner is used as the simulation origin. Using the model, the irradiance spectra of HEO target are calculated for different target temperature. With the calculation results, the main wavelength range for HEO detection is analyzed. Using the equvalent temperature, the work also designs a simulative target, which has the similar IR characteristics of a HEO target. The simulator can be used in the ground test for the imaging sensor or target decoy

Allergic hyper-carcinoembryonic antigen syndrome: A syndrome summarized by case series

Allergic respiratory diseases can increase serum carcinoembryonic antigen levels. We report three cases experiencing allergic symptoms that proved refractory to inhaled corticosteroids but exhibited a positive response to long-term treatment with oral corticosteroids. This response was characterized by a synchronous alteration in serum eosinophil counts and carcinoembryonic antigen levels. Immunofluorescence assays indicated localized carcinoembryonic antigen production within eosinophils. In addition, we conducted a systematic review of patients exhibiting similar characteristics on PubMed. After comprehensively reviewing this unique pathophysiological condition, we herein introduced a novel term “Allergic hyper-carcinoembryonic antigen syndrome,” defined by the following criteria: (1) recurrent asthmatic attacks; (2) eosinophilia or pulmonary eosinophilic infiltrations accompanied by elevated serum carcinoembryonic antigen levels; (3) pulmonary lesions determined by imaging or biopsy; (4) exclusion of malignancy and infections; and (5) responsive to systemic corticosteroids. Allergic hyper-carcinoembryonic antigen syndrome suggests systemic corticosteroids should be introduced early when managing allergic patients with both eosinophilia and elevated serum carcinoembryonic antigen levels