Naval ship design is a complex engineering activity that develops a floatable-loadable-movable maritime object equipped with weapons and sensors. It encompasses many diverse disciplines in Engineering as in the following figure. Besides engineering, there are many other areas that influence naval ship design, e.g., operational research, national strategy, economy, etc.

Recently, the philosophy behind the naval ship design has been changed from the naval architecture-centric to the systems engineering-centric, since the complexity and uncertainty have become drastically increased. Due to the change of nature of modern war, the naval ship has employed multiple advanced weapons and sensors which had not existed in the 1980. Naval engineers need to deal with the total system rather than by the separate manner like hull structure, hydrodynamics, and propulsion. As a proper methodical framework, Systems Engineering (SE) has become often discussed in the Navy development community. SE provides a process, methods, and tools for supporting the development process of complex systems such as warships and aircrafts. The internal council of systems engineering (INCOSE) which was internationally organized in the 1990 defines SE as follows:

Systems Engineering is a transdisciplinary and integrative approach to enable the successful realization, use, and retirement of engineered systems, using systems principles and concepts, and scientific, technological, and management methods.

At NASA, SE is defined as a methodical, multi-disciplinary approach for the design, realization, technical management, operations, and retirement of a system. I agree with this definition. However, these abstract, very broad concepts may not take an obvious form. The explanation of SE is not a trivial task since there is no commonality between the systems. Thus, SE process mentioned in standards and rules must be tailored to accommodate the domain characteristics and user's specific requirements. More details about SE are recommended to refer the following web sites.

• NASA: fundamentals of systems engineering
• SEBoK: SE body of knowledge
• DAG: Defense acquisition guidebook

This domain uses a modified term of SE, TSSE. It is a SE approach applied to naval ship design through concept studies to detail design. It will help us understand the complexities and interdependencies of various military problems including operations, sustainments, and cost. Ultimately, it will guarantee the satisfaction of the navy's needs at a reasonable cost and schedule. There are many success stories to drive the competent solutions I and my coworkers have realized. See relevant slides at www.slideshare.net. You can explore other presentations relating to my SE research activities.

I recommend you to refer to the presentation titled 'Naval ship systems engineering capability of republic of Korea navy' given for the international meeting of the NATO ship design capability group (SDCG) held on March 2016. And I have another journal paper published in the Naval Engineers Journal in 2015. It explains the process, methods, tools, and environment (PMTE) implemented in past concept design projects conducted in 2012-2016.