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As an essential resource in the process of national economic development, oil and gas has a very important strategic position. As a non-renewable resource, various countries and regions attach great importance to the development and use of oil and gas resources. Generally, oil and gas resources are buried deep underground and are the most critical resources in geological exploration. Reservoir development is a very important work, in the development process involves a lot of professional content, if the development is not reasonable, there will be some geological problems. Therefore, this paper chooses reservoir engineering geological problems in oil and gas field development as the research object, first expounds the impact of reservoir geological characteristics on oil and gas field development, then analyzes the existing problems, and finally proposes corresponding solutions to improve the quality and efficiency of oil and gas field development.

The mission planning of Geostationary Earth Orbit (GEO) on-orbit refuelling with uncertain object satellites is studied in this paper. Three key problems should be resolved here: Object Satellite (OSc) selection, mission sequence planning and transfer trajectory optimization. The optimization goal is to select the OSc and find the optimal servicing sequence with the best optimization objective value. Three optimization objectives, i.e. fuel cost, the total number of the OScs and the sum of the OSc priority value are taken into account. Considering this mission as a hybrid optimal control problem, a mathematical model is proposed. Multi-objective particle swarm optimization is employed to address the model. Several mission scenarios are compared and discussed. Numerical experiments indicate that 1) the method developed in this paper could address the problem efficiently; and 2) OSc distribution and varieties in optimization objective emphasis have considerable influences on the optimization results.

The Selenium-Polysaccharides from Rich selenium Chemical explicitly defined the Edible Fungus (Se-EF) in Boiling water extraction by alcohol precipitation, analysis indicated that the there were main ingredient comprises xylose, dextrose, rhamnose, galactose, and arabinose. First investigate lipids Metabolic and lipoprotein lipase (LPL) activated in the selenium-rich -EF rich in cholesterol and prospects by feeding rich foods (PRD). The purpose of this study is to explore the prospect 1st fed cholesterol-enriched diet (PRD) of KM mice selenium -EF on cholesterol metabolism and lipoprotein lipase (LPL) activated of antioxidant capacity. In addition, studies of the relationship between atherosclerosis and total antioxidant capacity index (AI) and LPL activity (TAC). The results showed that selenium polysaccharide significantly reduce TC serum total cholesterol and LDL-C concentrations comparatively in with the CK control groups. Furthermore, orally administered of polysaccharide selenium notable enhance pay, lipoprotein lipase activity and reduce MDA levels, and artificial intelligence. These results indicate that the beneficial affects of selenium on -EF hypercholesterolemia precautions. In addition, oral administration of polysaccharide selenium notable enhance TAC and LPL activity in the meantime reduce MDA levels, the same as AI. These results indicate that Se-EF has a beneficial effect on the prevention of hyperlipidemia. These results indicate that the beneficial affects of selenium on -EF hypercholesterolemia precautions.

Image segmentation is a process of segmenting an image into non-intersecting regions containing homogeneous pixels that are inhomogeneous with those in other adjacent regions. In this paper, a possibilistic clustering algorithm incorporating grey-level histogram and spatial information (PCA_HS) for image segmentation is proposed. The grey-level histogram speeds up the algorithm and the spatial information enhances its robustness to noise and outliers. To assess the proposed algorithm, four widely used validity indexes are computed and discussed. As the experimental quantitative and qualitative results on real images with and without noise show, PCA_HS can preserve the homogeneity and integrality of the regions and hence is more effective and efficient than traditional PCA.

Objectives: To understand the knowledge and testing willingness of new students in vocational colleges in Chongqing City towards HIV/AIDS, and provide reference for HIV/AIDS prevention education for vocational college students. Methods: A combined method of cluster sampling and random sampling was used to conduct the survey. In November 2022, four vocational colleges in Chongqing City were selected, and classes of new students were randomly chosen to participate in the survey. In addition, the questionnaire was distributed to new students of the four colleges through WeChat public platform, and students voluntarily responded to the survey. Results: The awareness rate of HIV/AIDS-related knowledge among new students in the four vocational colleges was 67.53% (938/1389), and the awareness rate among students in medical majors was 78.59% (P

The Nb-16Si-20Ti-4Cr-1.5Al-4Hf-4Zr-1Ta-xB (x=0, 2, 4)-yMg (y=0, 0.2, 0.4) alloys were prepared by non-consumable arc melting. The effects of B and Mg addition on the microstructure and room temperature fracture toughness have been investigated. The results reveal that when the content of B element reached 4 at.%, the intermediate metastable phase Nb3Si was precipitated in Nb-Si based alloys. The cooperation of B and Mg synergistically enhances the room temperature fracture toughness of Nb-Si based alloy. B and Mg element causes the eutectic point of Nb-Si based alloy to shift to the right. The 2B-0.4Mg alloy shows the best fracture toughness, and its KQ value is 14.41 MPa·m 1/2, which increased by 34% compared to the matrix alloy. Crack deflection and secondary cracking increase the room-temperature fracture toughness of Nb-Si-based alloys.

Chiral sulfoxides are widely present in biologically active molecules and pharmaceuticals, and their efficient and green synthesis has been a hot research topic. This article reviews three main methods employed in the industrial-scale synthesis of esomeprazole: transition metal catalysis, bio-enzyme catalysis, and oxaziridine oxidation. The advantages, disadvantages, and innovative progress of each method are discussed, and the challenges faced in large-scale production are analyzed. Solutions such as catalyst design, reaction process optimization, and continuous flow processes are proposed, pointing out directions for achieving efficient and green manufacturing of chiral sulfoxides drugs, which is of great significance for promoting the sustainable development of related industries.

The Vietnam War was a splitting conflict that caused significant social, political, and cultural upheaval in American society. Tim O’Brien’s work explores the personal experiences of soldiers who fought in the war, their inner lives, and the complexities of telling true stories about the war. This paper discusses O’Brien’s “How to Tell a True War Story” as a representation of a unique literary work set in the context of the Vietnam War. The paper argues that O’Brien’s narrative style departs from traditional metanarrative styles by emphasizing individual traumas and inner experiences, which transcends the question of factual accuracy. The paper utilizes Jean-Francois Lyotard’s theory of metanarratives in the postmodern era to explore how O’Brien’s narrative style subverts traditional narrative structures, creating an emphasis on individual emotions and experiences. The paper argues that O’Brien’s narrative style, which includes fragmentary narration, personification of items, and conscious expressions from the narrator’s perspective, authentically elaborates the obscurity and disorder of people’s inner world during wars. This narrative style provides a meaningful way for people to empathize and connect with the text, especially during times of uncertainty and despair such as the COVID-19 pandemic. O’Brien disrupts metanarratives, making readers doubt their own viewpoints and beliefs, and deconstructs the textures of power and authority. While his work is significant in subverting authoritative storytelling, the loss of belief in overarching narratives may lead to social unrest, political upheaval, and economic instability. The combination of the metanarrative and the postmodern subversive narration might be a possible solution.

Fused mullite particles are used to prepare mullite porous ceramics by gel-casting method, using polysilicon waste and ρ-Al2O3 powder as the binder, and starch as the pore forming agent. The content of the pore forming agent was 20%, and the ratio of the mass of fused mullite particles to the mass of the binder was 9:1, 8:2, 7:3, and 6:4, respectively. The effects of binder content on the properties of mullite ceramics in terms of phase composition, microstructure, apparent porosity, compressive strength, bulk density, pore size distribution, and filtration pressure drop were investigated. It was found that prepared porous mullite possessed relatively high apparent porosity (56.64-58.19%), and low bulk density (1.28-1.31g/cm3). With increasing binder content, the sintering shrinkage rate increased from 2.07 to 5.92%, the compressive strength increased from 1.01MPa to 6.08MPa. Therefore, the preparation of mullite ceramics was a near net size preparation, and the prepared porous ceramics meet the requirements of flue gas filtration.

It is difficult for computer to understand the texts in unstructured Chinese language, which becomes an obstacle for further application of artificial intelligence in the power dispatch center. Understanding of the orders from human dispatchers is the premise for the collaboration of machine and human being in power system operation. Towards understanding of dispatching texts, this paper proposes a textual semantic analysis framework with active learning of the semantic structure knowledge. Firstly, the words are vectorized by the Skip-gram models. And the hierarchical clustering algorithm is designed to detect the sentence patterns. Then the knowledge base is set up by converting the sentence structure to their regular expressions. In application, define a proprietary semantic framework to extract important device information and to parse the semantic slot using dependency syntax. Application shows that the Chinese texts describing the operation mode switching process can be understood accurately by the computer program.

In this research, the Strength and deformation behaviors, cracking process, and local stress evolution of sandstone specimens containing a circular opening and two joints (called H-J sandstone specimens in this study) were researched by experiment and numerical simulation (two-dimension particle flow code). The effect of different joint positions around the opening has been specifically studied by changing the ligament angle (${\beta }$). The test results show that peak strength and peak strain firstly decrease then increase with the increasing ${\beta }$, while the peak strain presents an overall upward trend. Three types of coalescence failure patterns between the opening and joints formed, and the corresponding cracking process and acoustic emission (AE) characteristics are highly related to the ligament angle. Based on the micro-parameters calibration, a good agreement was achieved between experimental and numerical simulation. The numerical results show that the local stress evolution around the opening is highly corresponding to the cracking process. The microcracks initiation and propagation cause obvious stress fluctuations, drops or increasements of minimum principal stress, while the cracks coalescence results in obvious reduction of maximum principal stress and drops of stress-strain curve. It also be found that the stress distribution and magnitude around the opening tend to be closely related to both coalescence failure and strength characteristics of H-J specimens. Finally, the cracking mechanism between the opening and joints was revealed based on particle displacement fields. The results show that different cracking mechanism may cause different local stress changes, which finally determines the overall mechanical behavior of specimens.