• Journal of Korean Society for Quality Management
• /
• v.27 no.1
• /
• pp.111-134
• /
• 1999

Although the role of information system has been rapidly increasing in modern management, there have been few researches on the quality assurance in information system. This paper suggests how to apply quality function deployment(QFD) to information system development in order to build up user-centered quality assurance system. The main focus of the paper is how to design the linkages between management strategy, information systems, and the users using quality function deployment.

• Ocean and Polar Research
• /
• v.37 no.3
• /
• pp.179-188
• /
• 2015

This study was carried out to determine the optimal number of ARGO floats in the East Sea in order to maximize their applications. The dominant spatio-temporal scale, size of the domain, and the typical float lifetimes in the East Sea were taken into consideration. The mean spatial de-correlation scale of temperature on isobaric surfaces reaches about 60 km. The minimum necessary number of floats is about 82 on average in order to secure independent ARGO profiles with the de-correlation scale. Considering the float lifetimes, about 27 floats per year should be deployed to maintain the 82 ARGO float array every year. To obtain spatially uniform distribution of ARGO float data, mean residence time and dispersion rate (basin area/residence time) of ARGO floats were evaluated in each basin of the East Sea. A faster (slower) dispersion rate requires more (less) ARGO floats to maintain the spatially uniform number of floats. According to the analysis, it is likely that the optimal ratio of the number of floats for each basin is 1:2:4 corresponding to Ulleung Basin:Yamato Basin:Japan Basin. In order to maintain relatively uniform ARGO observing networks, it is necessary to establish a long-term plan for deployment strategy based on float pathways and the dispersion rate parameters estimated by using currently active ARGO float trajectory data as well as reanalysis data.

• Journal of Aerospace System Engineering
• /
• v.16 no.2
• /
• pp.63-72
• /
• 2022

As interest in microsatellites increases, research has been actively conducted recently on the performance and use, as well as the orbital design and deployment techniques, for the microsatellite constellations. The purpose of this study was to investigate orbital deployment techniques using thrust and differential atmospheric drag control (DADC) for the Walker-delta constellation. When using thrust, the time and thrust required for orbital deployment vary, depending on the separation speed and direction of the satellite with respect to the launch vehicle. A control strategy to complete the orbital deployment with limited performance of the propulsion system is suggested and it was analyzed. As a result, the relationship between the deployment period and the total thrust consumption was derived. It takes a relatively longer deployment time using differential air drag rather than consuming thrusts. It was verified that the satellites can be deployed only with differential air drag at a general orbit of a microsatellite constellation. The conclusion of this study suggests that the deployment strategy in this paper can be used for the microsatellite constellation.

• Journal of the Korean Professional Engineers Association
• /
• v.32 no.6
• /
• pp.44-47
• /
• 1999

This study deals with the quality strategy using brain science as the tool of productivity improvement. Especially, it is critically analyzed that the application of the brain theory to the new deployment methodology of quality management corresponds to the industrial improvement properly in points of performing quality and productivity, and contributing the growth of our society etc.

• Proceedings of the IEEK Conference
• /
• 2002.06a
• /
• pp.391-394
• /
• 2002

Because of great damages by illegal hacking, demand for security of the public network as well as the private is seemingly limitless. This critic리 requirement is leading ISPS to deploy new security services for their customers. In this paper, we present active responses for the security of a ISP's network, and describe the deployment of a new security service using the network secured by that responses.

• Journal of the Korea Society of Computer and Information
• /
• v.12 no.4
• /
• pp.221-228
• /
• 2007

Qualify Function Deployment(QFD) is a technique which was born in Japan as a strategy for assuring that quality is built into new products. QFD was first used in 1972 by Kobe Shipyard of Mitsubish Heavy Industrials Ltd. and was then referred to as the quality tables. After QFD is proposed, it has been applied by both many large and small companies around the world. Many studies related QFD are performed till now but study related "cost-based QFD(QFCD)" hasn't been performed actively. If cost-based QFD is not performed. the produced results will be included possibility that is not significant as well as realistic. Therefore, the purpose of this study is to improve effectiveness and efficiency for product development's result through QFD by introducing QFCD's concept and execution procedure.

• Journal of Digital Convergence
• /
• v.14 no.10
• /
• pp.45-51
• /
• 2016

The purpose of this paper is to plan deployment strategy of public key infrastructure for Malawi by considering the information and communication technology status on it. For this, we will review the information communication technology status on developing and least developed countries focused on Malawi and plan deployment strategy of mobile based public key infrastructure. First of all, we extract out security considerations for public key infrastructure, which is efficient for wireless communication, and design a new lightweight public key infrastructure apt to mobile device by considering Malawi's information communication technology status. Especially, the proposed mobile based public key infrastructure uses smartcards for all the processes of certificate. It could guarantee the same security as the wired counter part based on lightweight mobile device.

• Nuclear Engineering and Technology
• /
• v.45 no.3
• /
• pp.367-376
• /
• 2013

This study investigated mixing scenarios of the low and high conversion ratios (CRs) of fast reactors (FRs). The fuel cycle was modeled so as to minimize the spent fuel (SF) or transuranics (TRU) inventories. The scenarios were modeled for a single low CR of 0.61 and a high CR of 1.0. The study also investigated the mixing scenario of low-high CR and/or high-low CR. The SF and TRU inventories, associated with different scenarios, were compared to those of the light water reactor (LWR) once-through (OT) case. Also, the important isotope concentration and long-term heat (LTH) load were calculated and compared to those of the OT cycle. As a result, it is known that the deployment of FRs of low CR burns more TRU and results in a reduction of the out-of-pile TRU inventory and LTH with low deployment capacity. This study shows that the mixing strategy of FRs of low and high CR can reduce the SF and TRU inventories with lower deployment capacity as compared with a single deployment of FRs of high CR.

• Journal of IKEEE
• /
• v.13 no.4
• /
• pp.75-81
• /
• 2009

The cellular system in the next generation decreases the range of transmission of a signal as well as increases the rate of transmission adapting the method of multi-hop relaying with the relay. However, the fact of decreasing the range of transmission with the method of multi-hop relaying means increasing interferential amount in the outer cell; therefore, the deployment of the relay can affect to the function of the cellular system. In this thesis, the deployment of the relay is determined for the maximum rate of transmission, based on the transmission power of the relay and the variation of interferential amount. The condition to determine the deployment of the relay is analyzed with the mathematical model; in addition, its performance is verified through the result of a simulation. Based on the analysis of this thesis, the established deployment and transmission power of the relay to minimize the average outage probability exist. Furthermore, the relay contributes to enlargement of capacity of cells, decreasing the average outage probability in the situation of less severe interference between cells with reuse of frequency. However, the relay should be restrained in use in the situation of severe interference between cells due to the fact that the outage probability of inter-cells can be increased.

• The Journal of the Acoustical Society of Korea
• /
• v.43 no.2
• /
• pp.214-224
• /
• 2024

Sonobuoys are disposable devices that utilize sound waves for information gathering, detecting engine noises, and capturing various acoustic characteristics. They play a crucial role in accurately detecting underwater targets, making them effective detection systems in anti-submarine warfare. Existing sonobuoy deployment methods in multistatic systems often rely on fixed patterns or heuristic-based rules, lacking efficiency in terms of the number of sonobuoys deployed and operational time due to the unpredictable mobility of the underwater targets. Thus, this paper proposes an optimal sonobuoy placement strategy for Unmanned Aerial Vehicles (UAVs) to overcome the limitations of conventional sonobuoy deployment methods. The proposed approach utilizes reinforcement learning in a simulation-based experimental environment that considers the movements of the underwater targets. The Unity ML-Agents framework is employed, and the Proximal Policy Optimization (PPO) algorithm is utilized for UAV learning in a virtual operational environment with real-time interactions. The reward function is designed to consider the number of sonobuoys deployed and the cost associated with sound sources and receivers, enabling effective learning. The proposed reinforcement learning-based deployment strategy compared to the conventional sonobuoy deployment methods in the same experimental environment demonstrates superior performance in terms of detection success rate, deployed sonobuoy count, and operational time.