• Fire Science and Engineering
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• v.26 no.5
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• pp.41-47
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• 2012

As a core process in the manufacture of state-of-the-art industrial technologies such as semiconductor and LCD, a clean room is the most important process which can affect the performance and quality of products drastically. Nevertheless, scientific research on comprehensive safety measures from a fire protection standpoint is not being carried out in Korea. This study aims to derive measures to improve smoke control systems by identifying performance and problems of smoke systems installed in clean rooms as an LCD manufacturing process and analyzing fire and evacuation simulations considering several scenarios. As a result of analysis of fires and smoke in a clean roomas an LCD manufacturing process, it is found to be necessary to stop air handling units through interlocking in case of a fire and exhaust smoke out of the room through the top of FAB in consideration of buoyancy of smoke. It is also found to be necessary to install quick response sprinkler heads and accessories to accelerate the response time, because the heat-accumulating performance of sprinkler heads decreases in this application. Despite its low density of dwelling due to the automation process, clean room is characterized by an array of complex production equipment and working environment requiring dustproof clothes, which makes it difficult to acquire evacuation safety performance. Thus, thorough control of danger factors in processes and periodic education and training are required. It is also necessary to establish a level of domestic technologies equivalent to the level of standards of advanced countries in fire protection.

• Journal of the Korean Society for Precision Engineering
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• v.17 no.10
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• pp.192-199
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• 2000

The design of multi-stage gear drives is a time-consuming process because it includes more complicated problems, which are not considered in the design of single-stage gear drives. The designer has no determine the number of reduction stages and the gear ratios of each reduction stage. In addition, the design problems include not only dimensional design but also configuration design of gear drive elements. There is no definite rule or principle for these types of design problems. Thus the design practices largely depend on the sense and the experiences of the designer, and consequently result in undesirable design solution. A new and generalized design algorithm has been proposed to support the designer at the preliminary phase of the design of multi-stage gear drives. The proposed design algorithm automates the design process by integrating the dimensional design and the configuration design process. The algorithm consists of four steps. In the first step, the user determines the number of reduction stages. In the second step, gear ratios of every stage are chosen using the random search method. The values of the basic design parameters of a gear are chose in the third step by using the generate and test method. Then the values of the dimensions, such as pitch diameter, outer diameter and face width, are calculated for the configuration design in the next step. The strength and durability of each gear is guaranteed by the bending strength and the pitting resistance rating practices by using AGMA rating formulas. In the final step, the configuration design is carried out using simulated annealing algorithm. The positions of gears and shafts are determined to minimize the geometrical volume (size) of a gearbox while avoiding interferences between them. These steps are carried out iteratively until a desirable solution is acquired. The proposed design algorithm is applied to the preliminary design of four-stage gear drives in order to validate the availability. The design solution has considerably good results in both aspects of the dimensional and the configuration design.

• The KIPS Transactions:PartC
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• v.14C no.6
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• pp.463-470
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• 2007

Revocation is one of the main difficulties faced in implementing Public Key Infrastructures(PHs). Boneh, Ding and Tsudik first introduced a mediated cryptography for obtaining immediate revocation of RSA keys used in PKIs. Their method is based on the idea that each user's private key can be split into two random shares, one of which is given to the user and the other to an online security mediator(SEM). Thus any signature or decryption must be performed as a cooperation between a user and his/her associated SEM and revocation is achieved by instructing the mediator SEM to stop cooperating the user. Recently, Libert and Quisquater showed that the fast revocation method using a SEcurity Mediator(SEM) in a mRSA can be applied to the Boneh-Franklin identify based encryption and GDH signature schemes. In this paper we propose a mediated identity based signature(mIBS) with batch verification which apply the SEM architecture to an identity based signature. Libert's GDH siganture scheme is not forward secure even though forward security is an important and desirable feature for signature schemes. We propose an efficient key udating mediated signature scheme, mKUS based on mIBS and analyze its security and efficiency.

• The Korean Journal of Nuclear Medicine Technology
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• v.13 no.3
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• pp.181-184
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• 2009

Purpose: Automated system that immunoassay examination are used widely. However, sample to sample carryover can cause that the next patient sample is false positive. Materials and Methods: We test HBs Ag, HBs Ab, HBc Ab(IgG) with Automated pipetting system (Tecan). It was placed with very high concentrations followed by saline solution. During this experiment, The fixed tip of Automated system wash With 0.25 moL/L NaOH. The Measurement results of saline solution confirm the occurrence of carryover. Results: Results of saline solution with 0.25 moL/L NaOH cleaning process was measured 100% negative, And results of patient serum with 0.25 moL/L NaOH cleaning process is similar reported results. Conclusion: As Results, 0.25 moL/L NaOH cleaning process was avoid carryover in experiment, And we know results of the hepatitis test did not affected by this solution we recommend 0.25 moL/L NaOH cleaning process as the Prevention of carryover in the automated system with fixed Tips.

• Journal of Korea Multimedia Society
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• v.15 no.5
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• pp.651-663
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• 2012

Networked digital signage downloads necessary multimedia contents from a large-sized storage on WAN to its local disk of a limited size before starting their playback. If the required time to download the entire contents gets longer, a start time to play the contents at the digital signage could be delayed. In this paper, we propose a hybrid storage architecture that not only inserts an iSCSI storage layer between the existing local disk and the WAN storage, but offers a contents caching scheme in order to obtain all the necessary contents in digital signage rapidly. The proposed caching scheme determines how to place the downloaded contents both in the local disk and the iSCSI storage. Uniquely, the proposed caching scheme manages the iSCSI storage space by dividing it into two regions: (1) in one region, the digital signage can play the contents directly without downloading them into the local disk; (2) in the other region, the digital signage cannot. Performance evaluations on a simulator and an actual system with workloads of various contents show that a contents-downloading time of the hybrid storage architecture is at maximum three times shorter than that of the existing storage architecture.

• Cartoon and Animation Studies
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• s.27
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• pp.79-97
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• 2012

Comic book readers have respectively different reading speed and this means that time in comics is translated by readers' view. The authors arrange panels and gutters to control time, but time recognition in comics depends on the readers and generally it is the readers' role. On the contrary, the phenomenon having occurred by infinite canvas varied the authority of timing. Infinite canvas can give the comic book authors more authority of controlling timing than the readers by intervening in readers' relative time as an agents and transforming their fictive time into absolute time. Following to the concept of "Agency" in games, agency is the power which satisfies the players by reemergence of their intentions. Since some of digital comics absorbed the properties of other media such as animation and sound, we can see that the reader's timing agency is shifted to the author's timing agency. The purpose of this study is to analyse this phenomenon and to remind that agency motivated by the balance between material constraints and formal constraints becomes a condition of readability of digital comics but excessive timing constraints given to the readers causes a decrease of the readers' timing agency. This also can be a considerable matter when we produce digital comics.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.10
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• pp.158-166
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• 2018

Contrary to urban development, urban regeneration is a process of land development through conservation, restoration, and management. In particular, ecologically based urban regeneration is an attempt to improve the quality of life in an area, establish a stable settlement space, and revitalize the local economy by considering the ecological environment. In this regard, the objectives of this study were to establish theoretical concepts and analyze the successful foreign cases of ecologically based urban regeneration, and propose a direction of socio-economic regeneration along with the physical-environmental regeneration of urban areas in Korea. The study results suggest the following. First, strategies must be developed to coordinate public transportation, such as buses and subways, by considering the importance of bicycle riders, along with the sustainable-commuting system. Second, both the importance of planning parks and trails around water systems in various scales while maintaining the existing natural environment as well as using natural elements, such as electric vehicles and wind-power generation systems, were emphasized. Third, urban regeneration for increased energy efficiency requires specific architectural planning and facilities. Fourth, education and research for easy access by the public, as well as public-private partnership, will be needed in the regeneration process.

• The Journal of the Korea Contents Association
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• v.12 no.4
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• pp.438-447
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• 2012

The objectives of this research are: to provide fundamental data for tourism policy and investigate medical tourism attributes by IPA(Importance-Performance Analysis) to attract Japanese medical tourists to Korea. Utilizing Japanese medical tourists as subjects of inquiry, this study evaluated the importance of medical tourism selection attributes and the rate at which these attributes were performed. Consequently, this study deduced 'convenience, service quality, differentiation, approximation' factors by factor analysis as well as the ranking among each selection attributes using T-test. The importance-performance analysis showed 'Concentrate Here' in quadrant I, 'Keep up the Good Work' in quadrant II, 'Low Priority' in quadrant III and 'Possible Overkill' in quadrant IV. The results show that "Concentrate Here" part in quadrant I is reservation procedure rapidity and information system simplicity. This means that these attributes are very important but they indicate low performance. Thus, concentration among tourism managers should be focused along these attributes. The study, then, suggests that employee who speaks Japanese fluently should be arranged during reservation procedure. Furthermore, Japanese class should become mandatory during basic employee training to improve reservation procedure rapidity. Moreover, clinic websites should concentrate on accessibility of Japanese users in such a way that they can consult their needs on line. Finally, managers should find diverse ways to bring about good service rapidly and conveniently.

• Journal of the Korean Society of Marine Environment & Safety
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• v.18 no.4
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• pp.316-322
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• 2012

In the port of Ulsan with the area of harbor limit of $83km^2$, 25,432 vessels have been entering annually and only 35 vessels can anchor simultaneously at the anchorage. The area of harbor limit of Ulsan constitutes just 65 percent compared to $127.5km^2$ which is an average of main ports in Korea. In this regard, the port of Ulsan needs to expand the area of anchorages inevitably for enhancing the efficiency of port operation. To select the best anchorage area in Mipo harbor with the introduction of a concept of emergency anchorage, this study analyzed the safety of navigation and anchorage, and safety management, etc. in the prospected anchorage on the basis of the marine traffic survey observing traffic density. Furthermore, after drawing preliminary and final schemes through gathering the opinions from maritime users, safety management organizations and academic experts group, the best arrangement of emergency anchorage has been selected through the conference of interested parties. Then, the final scheme was also verified through figuring out the marine traffic system and carrying out the ship handling simulation.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.2
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• pp.702-709
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• 2018

A quick-hardened concrete track was developed to improve the aged ballasted track to a concrete track, and applied to earthworks and tunnels of main and urban railways. Rebars for reinforcement are not generally applied to prestressed concrete sleepers. On the other hand, many cracked sleepers have been observed in railroad sites. A wide sleeper, which is one of the main components of quick-hardened concrete track, should be structurally safe and crack-resistant in a ballasted and concrete track to avoid this problem. In particular, a wide sleeper manufactured by a post-tension method must have reinforcing bars applied to the rail-seat section. In this paper, static tests, dynamic tests, and fatigue tests were carried out to compare the flexural strength and crack resistance performance of a wide sleeper with and without reinforcing bars for a quick-hardened concrete track. As a result of the test, if some reinforcing bars are applied appropriately to the rail-seat section of a wide sleeper, it will be possible to prevent the occurrence of cracks, delay the expansion of the crack width, and the flexural fracture.