## 1 Introduction  
The fast-paced evolution of the science and technology industry has made technological innovation a key driver of socio-economic development and enterprise competitiveness. However, navigating the complex R&D landscape, characterized by rapid technological growth and interdependencies, poses challenges for enterprises. Therefore, it is vital for them to swiftly and accurately identify core technology topics and track development trends to seize market opportunities and maintain a competitive edge. Patents play a pivotal role in this process [1, 2]. Efficient analysis and interpretation of patent literature are crucial for identifying and analyzing core technology topics.  
Researchers have proposed various methods to mine and identify technical themes in patents and unveil technological evolution processes, focusing on fine-grained analysis data. These methods include patent classification numbers, citation networks, and text content analysis [3, 4]. However, relying solely on patent classification numbers may hinder accurate identification due to the vast array of technical topics. Similarly, analysis based on patent citation networks suffers from time lags and lacks continuity in tracking technical evolution. In contrast, analyzing patent text content offers a more objective approach, free from subjective biases. By delving into patent text, this method can effectively uncover potential technical themes and reveal their evolution patterns [5].  
This study employs LDA topic modeling and TF-IDF text vectorization methods to comprehensively identify core technical topics in unmanned ships through a time-series dynamic analysis of patent text content. The study offers insights into technology development characteristics and future directions by delving into the evolution intensity and content changes of these core technology topics. Through meticulous analysis of patent text content, we aim to uncover core technical themes and their evolution patterns, providing valuable insights into the development trends in this technical field and offering new directions for technological innovation. Furthermore, this study presents a novel perspective on theoretical research regarding core technology identification and evolution, addressing limitations observed in previous studies.  
The main contributions of this paper are as follows. (i) Theoretical implications: Potential technological development opportunities are explored in technological innovation. Identifying the dynamic evolution of relevant technology development can provide more real-time insight and help capture changes in technology development in a timely manner, thus accelerating the innovation process. It reveals the evolutionary path of its technical themes and promotes innovation and development between technologies. (ii) Practical implications: It can excavate the core technology of unmanned ships, master the development path of core technology, and provide suggestions for enterprises to innovate unmanned ship technology. This paper applies theoretical research to real-life situations and identifies unmanned ship hotspot technologies that help shipping companies make decisions on unmanned ship technology development.  
This paper is structured as follows. Section 2 reviews the theoretical background of the main methods and techniques, including the current state of development of unmanned ship technology, patent technology identification, and evolution analysis. Section 3 explains the research thinking and the process of technology theme identification and evolution. Section 4 describes the application process using the example of unmanned ships. Section 5 discusses unmanned ship technology development trends. Finally, Section 6 concludes the paper, reviewing its limitations and recommending subsequent research.