• The Journal of Society for e-Business Studies
• /
• v.6 no.1
• /
• pp.17-33
• /
• 2001

EC(Electronic Commerce) which is done on the virtual space through Internet has strong point like independence from time and space. On the contrary, it also has weak point like security problem because anybody can access easily to the system due to open network attribute of Internet, Therefore, we need the solutions that protect the EC security problem for safe and useful EC activity. One of these solutions is the implementation of strong cipher system. YK2(Young Ku King) cipher system proposed in this paper is good solution for the EC security and it overcome the limit of current block cipher system using 128 bits key length for input, output, encryption key and 32 rounds. Moreover, it is designed for the increase of time complexity by adapting more complex design for key scheduling algorithm regarded as one of important element effected to encryption.

• Proceedings of the KIEE Conference
• /
• 1999.07c
• /
• pp.1276-1278
• /
• 1999

This paper proposed the optimal operational scheduling of cogeneration system for paper mill connected with several auxiliary devices. Auxiliary devices that include auxiliary boiler, waste boiler and sludge incinerator operate with multi-cogeneration system. Especially environment element was considered in objective function to solve environment problem. Electricity can be purchased through power system from utility. The proposed operational strategy on cogeneration system for paper mill to increase energy efficiency can be applied to the similar cogeneration system in industrial field.

• 제어로봇시스템학회:학술대회논문집
• /
• 1992.10a
• /
• pp.1051-1059
• /
• 1992

Two types of digital repetitive control systems are analyzed and designed to reduce the error spectrum including not only harmonic but also non-harmonic components. First, a novel gain scheduling algorithm is suggested for conventional and modified repetitive controller is scheduled to reduce the infinite norm of error in frequency domain. For this, the relative error transfer function is mewly defined as the ratio of the error spectrum for the system with a repetitive controller to the error spectrum for the system with a repetitive controller to the error spectrum for the system without a repetitive controller. Secondly, as an alternative of a repetitive control system with the gain scheduling, a repetitive control system with higher order repetitve function is analyzed and designed, where instead of equal weightings, weightings of the higher order repetitive function is determined in such a way that the infinite norm of relative error transfer function is minimized. To show the validities of proposed methods, computer simulation results are illustrated for a typical disk drive head positioning servo system.

• Proceedings of the KIEE Conference
• /
• 1999.11b
• /
• pp.291-293
• /
• 1999

This paper proposed the optimal operational scheduling of cogeneration system for paper mill connected with several auxiliary devices. Auxiliary devices that include auxiliary boilers, waste heat boilers and sludge incinerators operate with multi-cogeneration systems. Especially environment element was considered in objective function to solve the environment problem. And GAs(Genetic Algorithms) was applied to optimize and to analyse nonlinear operational property of cogeneration system of paper mill connected with several auxiliary devices. C-language was used to GAs computation. Electricity can be purchased through power system from utility. The proposed operational strategy on cogeneration system for paper mill to increase energy efficiency can be applied to the similar cogeneration system of industrial field.

• Proceedings of the Safety Management and Science Conference
• /
• 2003.11a
• /
• pp.93-96
• /
• 2003

In this regard, the newly focused logistics information system makes reducing the expenses of whole logistic available by cutting down the expenses of materials, transportation and stock and also, it allows the company to cut down the procurement expense through the reduced lead-time and rationalize producing plans by eliminating the uncertain orders and fluctuation in procurement. It further more optimizes the efficiency of over all productions by meeting the dead line for delivery to the customers. In the recent environment of globalization where fierce competitions exist between manufacturers, logistics plays important role in the strategies of companies, and managements of companies try their best efforts in establishing the strategy to accomplish the innovative relationship between supply chain channels. Therefore, in this study, we try to suggest the model of consolidated logistics system that is integrated logistics information system with suggesting the better way of logistics and comparative analysis with logistics system to resolve the difficulties numbers of companies face after realizing what logistics information system is in Korea.

• Journal of Korean Society of Industrial and Systems Engineering
• /
• v.21 no.47
• /
• pp.125-138
• /
• 1998

In this paper, we investigate the effect of re-entrance to the same work station in a job shop with multiple identical machines. System A is defined as the system in which re-entrance is not permitted, and system B is defined as the system in which re-entrance is permitted. By the analytical result of the queueing network, we find that the two systems have the same queue length distributions and utilizations under FIFO dispatching rule when all parameters are same. Simulation models are developed for various comparisons between the two systems, and simulation experiments are conducted for the combinations of five dispatching rules, two average workloads and two due date allowances. Five performance measures are selected for the comparison. The simulation results show that permitting re-entrance affects for some combinations of system environments.

• Journal of the Optical Society of Korea
• /
• v.13 no.4
• /
• pp.456-463
• /
• 2009

We introduce a holographic data storage system for intermediating between small data sets and mass holographic data recording. It employs a holographic sequentially superimposed recording technique. We discuss a time scheduling technique for making uniform reconstruction of sequentially recorded holograms and we show experimental results. We also discuss the Bragg selectivity of sequentially recorded holograms. The maximum storage density of our system is estimated to be 224kbit/$mm^2$. Our system is useful as an intermediate recording system before recording mass holographic data in a larger system.

• Journal of Intelligence and Information Systems
• /
• v.8 no.2
• /
• pp.71-89
• /
• 2002

In this paper, an integrated planning system is introduced for the efficient operation of container terminal. It consists of discharging and loading planning, yard planning, and berth scheduling subsystem. This interface of this system is considered for user's convenience, and the rule-based system is suggested and developed in order to make planning with automatic procedures, warning functions for errors.

• Journal of Broadcast Engineering
• /
• v.11 no.3 s.32
• /
• pp.311-319
• /
• 2006

Platform operators adopted ATSC standard send only their own channel program schedule information, so in order for the viewer to see other channel information, they have to tune the channel to the other. This issue arises from the operators' lack of bandwidth and the business interest conflicts between the platform operators. This paper guides how ATSC standard could be used within Xlet based application to display other channel information through the ISG (Integrated Scheduling Guide) technology via interactive return channel services. Its own channel information can be displayed by using on-air PSIP (Program and System Information Protocol) data.

• Journal of Electrical Engineering and Technology
• /
• v.12 no.4
• /
• pp.1369-1375
• /
• 2017

This paper presents an optimal operation scheduling algorithm for a smart home with energy storage system, electric vehicle and distributed generation. The proposed algorithm provides the optimal charge and discharge schedule of the EV and the ESS. In minimizing the electricity costs of the smart home, it considers not only the cost of energy purchase from the grid but also the life cost of batteries. The life costs of batteries are calculated based on the relation between the depth of discharge and life time of battery. As the life time of battery depends on the charge and discharge pattern, optimal charge and discharge schedule should consider the life cost of batteries especially when there is more than one battery with different technical characteristics. The proposed algorithm can also be used for optimal selection of size and type of battery for a smart home.