• Proceedings of the SAREK Conference
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• 2007.11a
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• pp.352-357
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• 2007

The objective of this study is to find the optimal set-point of a hybrid Plant, which is combined by renewable energy plant of the GSHP(Ground Source Heat Pump) and the conventional plant(chiller, boiler). The work presented in this study was carried out by using the EnergyPlus(Version 2.0). In order to validate the simulation model, field data were measured from a building. The GSHP was used as a base plant and the conventional plant as the assistant plant. Various temperatures were controlled (zone summer set-point, zone winter set-point, chilled water temperature, hot water temperature) to find the optimal set-point temperature of the system. The influence of the various set-points were analyzed seasonally.

• Journal of Information Processing Systems
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• v.6 no.4
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• pp.553-562
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• 2010

The core services in cloud computing environment are SaaS (Software as a Service), Paas (Platform as a Service) and IaaS (Infrastructure as a Service). Among these three core services server virtualization belongs to IaaS and is a service technology to reduce the server maintenance expenses. Normally, the primary purpose of sever virtualization is building and maintaining a new well functioning server rather than using several existing servers, and in improving the various system performances. Often times this presents an issue in that there might be a need to increase expenses in order to build a new server. This study intends to use grid service architecture for a form of server virtualization which utilizes the existing servers rather than introducing a new server. More specifically, the proposed system is to enhance system performance and to reduce the corresponding expenses, by adopting a scheduling algorithm among the distributed servers and the constituents for grid computing thereby supporting the server virtualization service. Furthermore, the proposed server virtualization system will minimize power management by adopting the sleep severs, the subsidized servers and the grid infrastructure. The power maintenance expenses for the sleep servers will be lowered by utilizing the ACPI (Advanced Configuration & Power Interface) standards with the purpose of overcoming the limits of server performance.

• Journal of Information Technology Services
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• v.11 no.4
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• pp.107-121
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• 2012

The core infra-technology in the ubiquitous era, RFID which has taken action from the public institution with the pilot projects as well as the practical projects is gradually extending its spectrum to the private enterprises. Along with its expansion, the audit required on the RFID-based information system is also growing in the industry. Especially, since RFID-based information systems, especially compared to other information systems, are likely to be exposed to many threats, the security audit for them is being emphasized. This paper suggests security audit checking items for the RFID-based information system, which can be used to perform the efficient security audit. The security audit checking items consist of eight basic checking items, each of which consists of detailed review items and can be applied for each building steps of the system(analysis, design, implementation, testing, and development). Finally, this paper confirmed the efficiency of the security audit checking items proposed in this paper through survey by the experienced auditors and analysis of practical audit cases.

• The Korean Journal of Emergency Medical Services
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• v.19 no.3
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• pp.117-138
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• 2015

Purpose: This study was performed targeted to paramedic and doctors, to examine the frequency, importance, and admissibility of the tasks of paramedics, and to establish as a basis for expanding their business scope. Methods: The subjects were 282 paramedics and 58 doctors, and the study was performed from October 20 to November 19, 2014. The statistical analysis was done by using SPSS/WIN 20.0. Results: The results showed the difference between the legal business scope of paramedics and the actually performed work. The frequently covered areas were trauma, cardiac arrest, and respiratory care; however, severity classifications were the most important. Concerning drug administration, epinephrine administration seemed to be the most necessary. Conclusions: The findings of this study can be used as basic data to broaden the capacity building and business scope of paramedics. Furthermore, to increase the resuscitation rate of emergency patients, the various tasks of paramedics must be incorporated, and these should be supported by laws and institutions.

• Journal of Integrative Natural Science
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• v.11 no.4
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• pp.192-196
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• 2018

The mobile agent paradigm can be exploited in a variety of ways, ranging from low-level system administration tasks to middle ware to user-level applications. Mobile agents can be useful in building middle-ware services such as active mail systems, distributed collaboration systems, etc. An active mail message is a program that interacts with its recipient using a multimedia interface, and adapts the interaction session based on the recipient's responses. The mobile agent paradigm is well suitable to this type of application, since it can carry a sender-defined session protocol along with the multimedia message. Mobile agent communication is possible via method invocation on virtual references. Agents can make synchronous, one-way, or future-reply type invocations. Multicasting is possible, since agents can be aggregated hierarchically into groups. A simple check-pointing facility has also been implemented. Another proposed solution is to use multi agent computer systems to access, filter, evaluate, and integrate this information. We will present the overall architectural framework, our agent design commitments, and agent architecture to enable the above characteristics. Besides, the each information needed a mobile agent system such as text, graphic, image, audio and video etc, constructed a great capacity multimedia database system. However, they have problems in establishing connections over multiple subnetworks, such as no end-to-end connections, transmission delay due to ATM address resolution, no QoS protocols. We propose a new connection management scheme in the thesis to improve the connection management involved of mobile agent systems.

• Journal of Korean Library and Information Science Society
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• v.49 no.4
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• pp.73-91
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• 2018

This study attempts to suggest effective strategies for small library services in Busan metro area. There has been a steady increase of small libraries that provide user friendly services for local residents. Local governments that is interested in such roles as community spaces based on the familiarity and flexibility of small libraries keep building and operating small libraries in Korea. This study, in this regard, surveyed the small libraries established and operated by a specific local government and analyzed the significance and problems in managing small libraries. In this study, we obtained data from observations, dialogues with managers and users through actual visit surveys to find out the limitations and difficulties of local small libraries.

• Geomechanics and Engineering
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• v.17 no.3
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• pp.287-294
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• 2019

The finite element method (FEM) is widely used to evaluate the seismic performance of pile-supported buildings. However, there are problems associated with modeling the pile end resistance using the FEM, such as the dependence on the mesh size. This paper proposes a new method of modeling around the pile tip to avoid the mesh size effect in two-dimensional (2D) analyses. Specifically, we consider the area of influence around the pile tip as an artificial constraint on the behavior of the soil. We explain the problems with existing methods of modeling the pile tip. We then conduct a three-dimensional (3D) analysis of a pile in various soil conditions to evaluate the area of influence of the soil around the pile tip. The analysis results show that the normalized area of influence extends approximately 2.5 times the diameter of the pile below the pile tip. Finally, we propose a new method for modeling pile foundations with artificial constraints on the nodal points within the area of influence. The proposed model is expected to be useful in the practical seismic design of pile-supported buildings via a 2D analysis.

• Journal of Information Technology Services
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• v.18 no.1
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• pp.45-61
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• 2019

Blockchain technology, which enables transparent transactions among individuals without central control, opens up diverse business possibilities. It is also expected that blockchain will have a ripple effect on the entire area of society including finance, manufacturing, distribution, and the public sector. Previous studies related to the blockchain also deals with its functional features and application to industrial and public fields. In the new technology such as blockchain, it is necessary to know what social perception is in order to create technological development environment, but there is a lack of research on it. Therefore, this study aims to find out the implications for industrial and policy direction by analyzing issues related to the blockchain in South Korea and the US through text mining. From these two countries, we collected text data related to blockchain in online communities and internet articles. Then, we did co-occurrence analysis and topic modeling on them respectively. As a result of this study, we have found common points and differences in keywords and topics extracted from social media in the two countries. Based on them, we can offer helpful suggestions for building a sound blockchain ecosystem, and directions for future research.

• ETRI Journal
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• v.44 no.2
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• pp.220-231
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• 2022

Building smart transportation services in urban cities has become a worldwide problem owing to the rapidly increasing global population and the development of Internet-of-Things applications. Traffic congestion and environmental concerns can be alleviated by sharing mobility, which reduces the number of vehicles on the road network. The taxi-parcel sharing problem has been considered as an efficient planning model for people and goods flows. In this paper, we enhance the functionality of a current people-parcel taxi sharing model. The adapted model analyzes the historical request data and predicts the current service demands. We then propose two novel online routing algorithms that construct optimal routes in real-time. The objectives are to maximize (as far as possible) both the parcel delivery requests and ride requests while minimizing the idle time and travel distance of the taxis. The proposed online routing algorithms are evaluated on instances adapted from real Cabspotting datasets. After implementing our routing algorithms, the total idle travel distance per day was 9.64% to 12.76% lower than that of the existing taxi-parcel sharing method. Our online routing algorithms can be incorporated into an efficient smart shared taxi system.

• Journal of Information Technology Services
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• v.21 no.5
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• pp.15-28
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• 2022

Recently, government agencies are actively adopting the platform model as a means of public policy. However, existing studies on the public platform are minimal and have focused on user experiences or the possibility of public usage of the platform model. Now the research concerning building governance structure and utilizing network effects of the platform after adopting the platform model in the public sector is keenly required. This study intended to ignite academic dialogue on the governance of public platforms in the context of digital transformation. This study focused on a case of the 'Special delivery,' a public delivery app established by Gyeonggi-do. In order to analyze the characteristics of the public platform and its governance structure, data were collected from press releases, policy reports, and news articles. Data was analyzed using the frame of Hagui's platform design factors and Ansell & Gash's collaborative governance model. The results of the public platform analyses showed 1) incompleteness in the value trade-off accounting, which was designed for platform business based on general cost-benefit analysis, and 2) a closed governance structure that limits direct participation of diverse user groups(i.e., service provider, customer) in order to enhance providers' utility by preventing customers' excessive online activities. The results of this study provided theoretical and policy implications regarding designing the strategy for accounting for value trade-offs and functioning governance structure for public platforms.