A mobile ad hoc network (MANET) is a non-centralized, self-organized, and self-managed wireless ad hoc network that is used in a specific circumstance. The changing nature of the network's architecture and nodes necessitates a routing protocol to ensure efficient source-to-destination communication. MANET manipulates different sectors of life such as rescue and emergency operations, real-time information, interpersonal communication, network portioning, and catastrophe management due to its ad hoc and non-identical uses. Routing and maintenance are critical parts of effective time management and considered research study for MANET communication. This study focuses on the routing and maintenance process of MANET that has dynamic change in topology and nodes to deliver data rapidly. The motivational component of MANET for the research is route discovery, and several techniques have been proposed for it. Each has higher expectations than the other. This comparative analysis reveals issues for route discovery and maintenance of MANET communication, such as whether one is better in different network conditions than the others. This study examines the literature on MANET route discovery and maintenance strategies. As a result, a comparison of several routing protocol techniques is made. To achieve improvement, these methods include some suggestions for performance improvement using routing protocols especially in disaster management. This study presents directions for future experimentation, which will be pursued to identify the most advantageous collection of tactics for meeting the needs of various applications.

The present article aims to review and evaluate the practiced and classical techniques, tools, models, and systems concerning automatic information extraction (IE) from published scientific documents like research articles, patents, theses, technical reports, and case studies etc. IE is performed for various reasons such as better indexing, archiving, searching, and retrieving. That is mainly used by the search engines and the indexing services as well the digital libraries and semantic web. In this regard, several studies have been conducted targeting various nature of documents. The study pays special consideration to the successful IE models, algorithms and approaches applied to structural IE from published documents. To grasp this, the paper is classified into several segments and each segment covers a significant aspect of IE. Furthermore, to validate their benefits and drawbacks, a comparative study of all the approaches have been conducted in terms of various performance factors like precision, accuracy, recall and F-score. Potential areas of improvement have been emphasized as research gap for the scholars in the closely related areas. Ultimately, a comprehensive summary of the evaluation is presented in tabular form and review is concluded. It was observed that the hybrid methods outperform the other methods due to their versatile nature to address various document formats.