• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.32 no.11A
• /
• pp.1086-1095
• /
• 2007

This paper proposes a novel non-coherent TOA estimation scheme using multiple correlation process on the existence of multiple simultaneously operating piconets (SOPs). Impulse radio-ultra wideband (IR-UWB) based on direct sequence spread spectrum (DSSS) using Gold sequence is employed in order to discriminate each piconet. In order to enhance the characteristic of correlation, this paper presents the method of multiple mask operation (MMO). The time of arrival (TOA) of direct line of sight (DLOS) path is estimated via two step coarse/fine timing detection. To verify the performance of proposed scheme, two distinct channel models approved by IEEE 802.15.4a Task Group (TG) are considered. According to the simulation results, it could conclude that the proposed scheme have performed better performance than the conventional method well even in densed indoor multi-path environment as well as in the existence of multiple SOPs.

• Korean Journal of Computational Design and Engineering
• /
• v.14 no.1
• /
• pp.60-68
• /
• 2009

Because of the reduced product life-cycle, industries are making an effort to bring down the process planning time. In the traditional approach, we have to analyze established process planning, then design the time chart based on process information and drawing the formal time chart such as SOP(sequence of operation). Thereafter, it will be converted to PLC code that is a time consuming and redundant job. Similarly, Industrial automated process uses PLC Code to control the factory; however, control information and control code(PLC code) are difficult to understand. Hence, industries prefer writing new control code instead of using the existing one. It shows the lack of information reusability in the existing process planning. As a result, to reduce this redundancy and lack of reusability, we propose SOS-Net modeling method. Unlike past stabilized process planning that is rigid to any change; our proposed SOS-Net modeling method is more adaptable to the new changes. The SOS-Net model is easy to understand and easy to convert into PLC Code accordingly. Therefore, we can easily modify the control information and reuse it for new process planning. The proposed model plays an intermediary role between process planning and PLC code generation. It can reduce the process planning and implementation time as well as cost.

• Journal of the Korea Safety Management & Science
• /
• v.17 no.2
• /
• pp.67-78
• /
• 2015

The purpose of the establishment of corporation's Business Continuity Plan(BCP) is to maintain corporations' own business and establish the response plan in order to resume operation in a short time period when crisis situations occur due to natural disaster and human error. This study has presented all types of procedures and criteria which are needed to establish the airport crisis response system in order to maintain the business continuity by utilizing BCP technique. Basically the risk response procedures must be established in the process of (1) preparation stage, (2) plan development stage, (3) documentation stage, (4) test & maintenance stage. The guideline has been suggested that each stage must be carried out in the sequence of Policy & Planning Responsibility, Business Impact Analysis, Recovery Strategy & Plans, Emergency Plan & SOP, Training Awareness and Maintenance & Review