• Journal of Environmental Science International
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• v.29 no.9
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• pp.871-883
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• 2020

Due to recent heavy rain events, there are increasing demands for adapting infrastructure design, including drainage facilities in urban basins. Therefore, a clear definition of urban rainfall must be provided; however, currently, such a definition is unavailable. In this study, urban rainfall is defined as a rainfall event that has the potential to cause water-related disasters such as floods and landslides in urban areas. Moreover, based on design rainfall, these disasters are defined as those that causes excess design flooding due to certain rainfall events. These heavy rain scenarios require that the design of various urban rainfall facilities consider design rainfall in the target years of their life cycle, for disaster prevention. The average frequency of heavy rain in each region, inland and coastal areas, was analyzed through a frequency analysis of the highest annual rainfall in the past year. The potential change in future rainfall intensity changes the service level of the infrastructure related to hand-to-hand construction; therefore, the target year and design rainfall considering the climate change premium were presented. Finally, the change in dimensional safety according to the RCP8.5 climate change scenario was predicted.

• Journal of Korean Society of Archives and Records Management
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• v.18 no.2
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• pp.189-214
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• 2018

Archival description is considered as a creation and curation process, and the results of the descriptive records can be used for archival information service. Therefore, various archival descriptive standards provide essential guidelines for establishing a semantic and synthetic structure of the archival records. In this study, the structural aspects of the archival descriptive standards were analyzed and an experimental mapping between General International Standard Archival Description (ISAD(G)), the archival standard, and CIDOC Conceptual Reference Model (CIDOC CRM), the domain ontology of cultural heritage field was performed. The data structure of ISAD(G) is examined in advance and mapping was performed using Karma as a platform. It was thus concluded that there is a need to understand the ontology-based mapping method and the event-focused domain ontology. Moreover, developing a CIDOC CRM-compatible archival ontology and restructuring the legacy ISAD(G) are needed.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2002.11a
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• pp.545-549
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• 2002

For the efficient method for acquisition of informations suitable to user's preferences and objectives in distributed environment, various researches on push agent which automatically processes its roles and sends the results to users are continued. The existing push agent models have induced increasing network overheads and traffics by continuous transmission of informations in the network environment of limitative bandwidth. In this paper, for the solution of the problems on these existing push agent systems and their interoperability, we design a push agent model based on CORBA event service. The proposed model solves the above problems and provides the retrieved results which are more suitable for user's requirement more fast and stably through the optimal path searching and controling method. And, it also supports the filtering technique for processing the duplicated or useless data that comes from the various distributed information systems.

• The KIPS Transactions:PartA
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• v.18A no.5
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• pp.181-192
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• 2011

Information superiority is an essential factor in modern warfare and it can be archived by efficient information exchange between systems. Various computing systems are installed on the today's navy vessels. However, it is hard to improve interoperability and efficiency of information exchange since the configurations of installed systems are varying. The military standard and commercial standard are mix-used between systems. In this paper, we propose an information exchange architecture based on Pub/Sub model as a communication middleware to improve interoperability as well as enhancing scalability. We also propose a novel tree matching algorithm to improve a performance of PubSub broker. In the proposed algorithm, each tree nodes have information about predicates of subscription that can reduce event matching time. The performance evaluation results show our proposed algorithm reduces time for matching predicates compare with other algorithms.

• Journal of KIISE:Information Networking
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• v.36 no.3
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• pp.173-183
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• 2009

We present a real-time monitoring system for detecting anomalous network events using the entropy. The entropy accounts for the effects of disorder in the system. When an abnormal factor arises to agitate the current system the entropy must show an abrupt change. In this paper we deliberately model the Internet to measure the entropy. Packets flowing between these two networks may incur to sustain the current value. In the proposed system we keep track of the value of entropy in time to pinpoint the sudden changes in the value. The time-series data of entropy are transformed into the two-dimensional domains to help visually inspect the activities on the network. We examine the system using network traffic traces containing notorious worms and DoS attacks on the testbed. Furthermore, we compare our proposed system of time series forecasting method, such as EWMA, holt-winters, and PCA in terms of sensitive. The result suggests that our approach be able to detect anomalies with the fairly high accuracy. Our contributions are two folds: (1) highly sensitive detection of anomalies and (2) visualization of network activities to alert anomalies.

• Journal of Advanced Navigation Technology
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• v.22 no.4
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• pp.288-294
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• 2018

The entertainment system of the aircraft has changed its paradigm in the form of using passenger electronic devices instead of using a fixed monitor. This has simplified the on-board equipment while the risk of safety has increased with the electric charging of portable electronic devices. Unlike personal portable electronic devices that do not have a transmission function, the use of Wi-Fi enabled electronic devices(T-PED) is allowed and the battery is required to be charged in the cabin. In this study, we used the NASA Aviation Safety Reporting System to investigate the effects of changes in wireless environment and entertainment service. Based on this, we analyzed the risks of personal electronic devices by sharing event occurrence cases caused by in-flight electronic equipment or passenger portable electronic devices(especially smart phones) from the viewpoint of aircraft safety management. This analysis includes identification of potential hazards and risk assessment, and finally the strategies for risk mitigation for safe use of portable electronic devices are suggested.

• Journal of Ecology and Environment
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• v.42 no.4
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• pp.308-316
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• 2018

Background: Genus Sasa, dwarf bamboos, are considered to be species that lower biodiversity in the temperate forests of East Asia. Although they have a long interval, they, the monocarpic species, have a unique characteristic of large-scale synchronized flowering. Therefore, once they have flowered and then declined, it may be an opportunity for suppressed surrounding species. A previous study reported that Sasa borealis showed specialized flowering nationwide with a peak in 2015. However, this was based on data from a social network service and field survey at Mt. Jeombong. Therefore, we investigated S. borealis in the forests of five national parks in order to determine whether this rare synchronized flowering occurred nationwide, as well as its spatial distribution. Results: We found a total of 436 patches under the closed canopy of Quercus mongolica-dominated deciduous forests in the surveyed transects from the five national parks. Of these patches, 75% occupied a whole slope area, resulting in an enormous area. The patch area tended to be larger in the southern parks. Half (219 patches) of the patches flowered massively. Among them, 76% bloomed in 2015, which was consistent with the results of the previous report. The flowering rate varied from park to park with that of Mt. Seorak being the highest. The culms of the flowering patches were significantly taller (F = 93.640, p < 0.000) and thicker (F = 61.172, p < 0.000). Following the event, the culms of the flowering patches declined, providing a good opportunity for the suppressed plant species. The concurrent massive flowering of the mature patches was believed to be triggered by some stress such as a spring drought. Conclusion: We confirmed that the rare synchronized flowering of S. borealis occurred with a peak in 2015 nationwide. In addition, we explored that S. borealis not only monopolized an enormous area, but also dominated the floors of the late-successional Q. mongolica-dominated deciduous forests. This presents a major problem for Korean forests. As it declined simultaneously after flowering, there are both possibilities of forest regeneration or resettlement of S. borealis by massively produced seeds.

• Health Policy and Management
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• v.29 no.2
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• pp.228-236
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• 2019

Background: This study investigates the impact of weekend admission with a patient safety indicator (PSI) on 30-day mortality among long-term insurance beneficiaries. Methods: Data were obtained from the National Health Insurance Service-Senior claim database from 2002 to 2013. To obtain unbiased estimates of odds ratio, we used a nested case-control study design. The cases were individuals who had a 30-day mortality event after their last medical utilization, while controls were selected by incidence density sampling based on age and sex. We examined the interaction between the main independent variables of weekend admission and PSI by categorizing cases into four groups: weekend admission/PSI, weekend admission/non-PSI, weekday admission/PSI, and weekday admission/non-PSI. Results: Of the 83,400 individuals in the database, there were 20,854 cases (25.0%) and 62,546 controls (75.0%). After adjusting for socioeconomic, health status, seasonality, and hospital-level factors, the odds ratios (ORs) of 30-day mortality for weekend admission/PSI (OR, 1.484; 95% confidence interval [CI], 1.371-1.606) and weekday admission/PSI (OR, 1.357; 95% CI, 1.298-1.419) were greater than for patients with weekday admission/non-PSI. Conclusion: This study indicated that there is an increased risk of mortality after weekend admission among patients with PSI as compared with patients admitted during the weekday without a PSI. Therefore, our findings suggest that recognizing these different patterns is important to identify at-risk diagnosis to minimize the excess mortality associated with weekend admission in those with PSI.

• Steel and Composite Structures
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• v.32 no.1
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• pp.1-19
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• 2019

The aim of the paper is the prediction of the seismic collapse mode of steel storage pallet racks under seismic loads. The attention paid by the researchers on the behaviour of the industrial steel storage pallets racks is increased over the years thanks to their high dead-to-live load ratio. In fact, these structures, generally made by cold-formed thin-walled profiles, present very low structural costs but can support large and expensive loads. The paper presents a prediction of the seismic collapse modes of multi-storey racks. The analysis of the possible collapse modes has been made by an approach based on the kinematic theorem of plastic collapse extended to the second order effects by means of the concept of collapse mechanism equilibrium curve. In this way, the dissipative behaviour of racks is determined with a simpler method than the pushover analysis. Parametric analyses have been performed on 24 racks, differing for the geometric layout and cross-section of the components, designed in according to the EN16618 and EN15512 requirements. The obtained results have highlighted that, in all the considered cases, the global collapse mechanism, that is the safest one, never develops, leading to a dangerous situation that must be avoided to preserve the structure during a seismic event. Although the studied racks follow all the codes prescriptions, the development of a dissipative collapse mechanism is not achieved. In addition, also the variability of load distribution has been considered, reflecting the different pallet positions assumed during the in-service life of the racks, to point out its influence on the collapse mechanism. The information carried out from the paper can be very useful for designers and manufacturers because it allows to better understand the racks behaviour in seismic load condition.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.24 no.8
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• pp.1071-1076
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• 2020

The importance of network separation is due to the use of the Internet with existing business PCs, resulting in an internal information leakage event, and an environment configured to allow servers to access the Internet, which causes service failures with malicious code. In order to overcome this problem, it is necessary to use network virtualization to separate networks and network interconnection systems. Therefore, in this study, the construction area was constructed into the network area for the Internet and the server farm area for the virtualization system, and then classified and constructed into the security system area and the data link system area between networks. In order to prove the excellence of the proposed method, a network separation construction study using network virtualization was conducted based on the basis of VM Density's conservative estimates of program loads and LOBs.