2012, Vol.7, No.5

Journal of Knowledge Information Technology and Systems 2023 KCI Impact Factor : 0.89

pISSN : 1975-7700 / eISSN : 2734-0570
https://journal.kci.go.kr/kkits

Job Shop scheduling problem is one of the most well-known NP-hard combinatorial optimization problems, and it is hard to obtain the optimal solution via numerical methods. Accordingly, probabilistic search methods such as genetic algorithm, simulated annealing and tabu search have been widely applied for solving Job Shop scheduling problems. In general, geneticalgorithms for Job Shop scheduling are designed to maintain a population consisted of active schedules, because the optimal schedules are included in the active ones. However, methods for generating active schedules such as Giffler and Thompson algorithm can be inefficient in that they are often computationally intensive. Instead, this paper proposes a semi active schedule based genetic algorithm called sa-GA. In sa-GA, a solution is represented as a natural permutation of operations, which is easily transformed into a semi active schedule. In addition, the genetic operations can be performed more quickly, and these aspects make sa-GA more efficient than the traditional active schedule based genetic algorithms. The experiment results show that sa-GA also concentrates on the active schedules in the population, and the optimal schedules can be obtained quickly.

Tele-conference system provides collaborative environment that allows scientists in the world to collaborate as in the same space exploiting large-sized display and audio devices. However, current systems mainly focuses on video conferencing so that it has difficulties in supporting collaborative works using immersive media data. In this paper we propose an enhanced tele-conference system supporting panoramic 3D display, various input devices for interaction, reliable networking, etc. The proposed system is expected to be applied to various networked collaborative applications including entertainment, education, scientific visualization, etc.

Installation of fire detection equipment aims to discover the fire in the building at the early stage for evacuating people quickly by using the warning system, and to protect the property from the spread of fire by operating various fire fighting facilities including fire extinguishing and smoke control system. Currently, about 73.5% of the fire-fighting firms in our country mark their sales less than five hundred million won a year. This means that the most of fire detection system of the small and medium size building adopts P-type Receiver. Therefore, in order to effectively prevent the small-medium size buildings, which use P-type Receiver, from fire, P-type Receiver must be supported by the remote automation monitoring system. Therefore this research proposes an automatic model that can monitor P-type Receiver efficiently. The automatic model proposed in this paper has been designed and implemented to monitor operational status of the detectors connected to P-type Receiver as well as to perform such function as fire detection and fire alarm transmission, etc.