• Journal of Digital Contents Society
• /
• v.4 no.2
• /
• pp.139-146
• /
• 2003

This paper explains the design and implementation of the ERA(Error Recovery Agent). ERA is a system that is suitable for detecting, sharing and recovering software error based on multimedia distance education system. This system consists of an ED, ES, and ER. ED detects an error by hooking techniques. ES is an agent which is an error sharing system for distributed multimedia distance education system. We propose how an error application can be treated and recovered as 'media' in a multimedia collaborative environment.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
• /
• v.16 no.5
• /
• pp.475-481
• /
• 2004

This paper presents a force model of the clean tube system, which was developed as a means of transferring air-floated wafers inside a closed tube filled with super clean air. The recovering force from the holes for floating wafers is modeled as a linear spring and thus the wafers motion is modeled as a mass-spring-damper system. The propelling forces are modeled as linear along with the wafer location. The paper also proposes a control method to emit and stop a wafer at the center of a control unit. It reveals the minimum value of the propelling force to leave from the control unit. In order to stop the wafer, it utilizes the exact time when the wafer arrives at the position to activate the propelling force. Experiments with the clean tube system built for the 12 inch wafer shows the validity of the proposed model and the algorithm.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2003.06a
• /
• pp.459-462
• /
• 2003

This paper presents a force model of the clean tube system, which was developed as a means for transferring the air-floated wafers inside the closed tube filled with the super clean air. The recovering force from the holes for floating wafers is modeled as a linear spring and thus the wafer motion is modeled as a mass-spring-damper system. The propelling forces are modeled as linear along with the wafer location. The paper also proposes the control method to emit and stop a wafer at the center of a control unit. It shows the minimum value of the propelling force to leave from the control unit. In order to stop the wafer, it utilizes the exact time when a wafer arrives at the position to activate the propelling force. Experiments with the clean tube system built for 12 inch wafer shows the validity of the proposed model and the algorithm.

• New & Renewable Energy
• /
• v.10 no.4
• /
• pp.29-35
• /
• 2014

Non-used waste heat has recently been paid special attention due to several global warming regulation and energy cost rising. In this study, therefore, thermal energy storage system which uses a solid type heat media has been investigated about the possibility of heat accumulation and heat release for thermal energy storage system. 35kWh of bench-scale thermal storage system was used to investigate the characteristics of the solid type heat media. From the result, it is shown that a solid type heat media should be divided to supply constant heat to the customers' side. It is also shown the flow direction should be considered to reduce temperature difference between top and bottom sides in the thermal storage system.

• Journal of the Korean Society of Tobacco Science
• /
• v.7 no.2
• /
• pp.189-197
• /
• 1985

The purpose of this study is to improve the method and the apparatus for recovering freon-11 used in a process for increasing the filling capacity of tobacco. The first, the theoretical recovery rate of freon-11 was calculated from vapour pressure and thermodynamic properties of freon-11. The second, the usability of theoretical data was evaluated by the comparison between the theoretical data and the experimental data from the pilot plant. The result obtained under the present experiment condition was quite similar to the rate at 15kg/cm2 and 5$^{\circ}C$, but the theoretical data evaluated were 0.1 to 0.3% lower than the experimental data at 20 to 25kg/cm2 and 5$^{\circ}C$. The recovery rate of the cooling and the compression system was about 95% with freon-11 used in this system and that with freon-11 concentrate of waste gas was about 3 to 3.6% at 20 to 25kg/cm2 and 5$^{\circ}C$.

• Journal of Digital Contents Society
• /
• v.16 no.1
• /
• pp.123-126
• /
• 2015

This paper described fault tolerance system running on distributed multimedia. We implemented the error manager service so that the users participated in distribute multimedia collaborative work may refer synchronized error objects as the same view to others. distributed multimedia environment are based on IP-USN(Internet Protocol - Ubiquitous Sensor Network) and M2M(Machine to machine). This is a system that is suitable for detecting, sharing and recovering software error in distribute multimedia CSCW(Computer Supportes Cooperated Work) environment. With error synchronization system, a group cooperating users can synchronize error applications.

• Journal of Korea Society of Digital Industry and Information Management
• /
• v.6 no.2
• /
• pp.107-118
• /
• 2010

This paper proposes a digital forensic method to a file creation transaction using a journal file($LogFile) on NTFS File System. The journal file contains lots of information which can help recovering the file system when system failure happens, so knowledge of the structure is very helpful for a forensic analysis. The structure of the journal file, however, is not officially opened. We find out the journal file structure with analyzing the structure of log records by using reverse engineering. We show the digital forensic procedure extracting information from the log records of a sample file created on a NTFS volume. The related log records are as follows: bitmap and segment allocation information of MFT entry, index entry allocation information, resident value update information($FILE_NAME, $STANDARD_INFORMATION, and INDEX_ALLOCATION attribute etc.).

• Journal of the Korean Society for Precision Engineering
• /
• v.21 no.3
• /
• pp.66-73
• /
• 2004

This paper presents wafer motion modeling of transfer unit in clean tube system, which was developed as a means for transferring the air-floated wafers inside the closed tube filled with the super clean airs. When the wafer is transferred in x direction with an initial velocity the motion along x direction can be modeled as a simple decaying motion due to viscous friction of the fluid. But, the motion in y direction is modeled as a mass-spring-damper system where the recovering force by air jets issued from the perforated is modeled as a linear spring. Experiments with a clean tube system built fur 12 wafer show the validity of the presented force and motion models.

• Journal of Information Technology Services
• /
• v.2 no.1
• /
• pp.111-121
• /
• 2003

This paper intents to suggest the re-engineering methodology to transform and integrate the legacy systems to new system in modern environment. While existing reverse engineering and re-engineering approaches have focused on analyzing and maintaining the source code of program. our methodology can provide the procedures and techniques for evolving into new system by recovering the reverse engineering informations and transforming them into component informations. Our methodology for componentization of legacy system is consisted of plan step, reverse engineering step, componentization step, and delivery step, and we describes activities and detail procedures about each step.

• Proceedings of the Korean Geotechical Society Conference
• /
• 2004.03b
• /
• pp.453-460
• /
• 2004

To prevent penetration of rainwater into the landfill site is the main purpose of the final cover in landfill sites. Conventional designs of landfill covers uses geotextiles such as geomembrane and GCL, and clay liners to lower the permeability of final covers of landfill sites. However, differential settlement and the variation of temperature in landfill sites cause the development of cracks or structural damage inside the final cover and it is also difficult to obtain clay - the main material of the compacted clay liner in Korea. Thus the former final cover system that suggests geomembrane and GCL or compacted clay liner has several limitations. Therefore, an alternative method is necessary and one of them is the application of SRSL(self-Recovering Sustainable Liner) material. SRSL is two different layers consist of individual materials that react with each other and form precipitates, and with this process lowers the permeability of the landfill final cover. SRSL generally is made up of two layers, so that when a internal crack occurs the reactants of the two layers migrate towards the crack and heal it by forming another liner. In this study the applicability of SRSL material for landfill final cover was examined by performing; (1) jar test to verify the formation of precipitate in the mixture of each reactants, (2) falling head test considering the field stress in order to confirm the decrease of permeability or prove that the hydraulic condctivity is lower than the regulations, (3) compression tests to judge weather if the strength satisfies the restricts for landfills, (4) freeze/thaw test to check the applicability of SRSL for domestic climate. In addition, the application of waste materials in the environmental and economical aspect was inspected, and finally the possibility of secondary contamination due to the waste materials was examined by performing elution tests.