• Applied Chemistry for Engineering
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• v.21 no.3
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• pp.278-283
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• 2010

The cationic polymerization of oxolane high explosives which have pendant explosive groups such as azido, nitrato and hydrazino is investigated theoretically using the semiempirical MINDO/3, MNDO and AM1 methods. The nucleophilicity and basicity of oxolane high explosives can be explained by the negative charge on oxygen atom of oxolane. The reactivity of propagation in the polymerization of oxolane can be represented by the positive charge on carbon atom and the low LUMO energy of active species of oxolane. The reaction of the oxolane high explosives in oxonium ion form to the open chain carbenium ion form is expected by computational stability energy (17.950~30.197 kcal/mol) of the oxonium ion and carbenium ion favoring the carbenium ion. The relative equilibrium concentration of cyclic oxonium ion and carbenium ion is found to be a major determinant of mechanism, owing to the rapid equilibrium of these catoinic forms. Based on calculation, in the prepolymer propagation step, $S_N1$ mechanism will be at least as fast as that for $S_N2$ mechanism.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.42 no.4
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• pp.939-949
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• 2017

Prognostics and health management(PHM) is actively utilized by industry as an essential technology focusing on accurately monitoring the health state of a system and predicting the remaining useful life(RUL). An effective PHM is expected to reduce maintenance costs as well as improve safety of system by preventing failure in advance. With these advantages, PHM can be applied to the battery system which is a core element to provide electricity for devices with mobility, since battery faults could lead to operational downtime, performance degradation, and even catastrophic loss of human life by unexpected explosion due to non-linear characteristics of battery. In this paper we mainly review a recent progress on various models for predicting RUL of battery with high accuracy satisfying the given confidence interval level. Moreover, performance evaluation metrics for battery prognostics are presented in detail to show the strength of these metrics compared to the traditional ones used in the existing forecasting applications.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2013.10a
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• pp.219-222
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• 2013

Recently, rapid innovation of Smartphone is changing the paradigm of our daily life. With the launch of Apple iPhone, there is an explosion of interest in Smartphone itself as well as Internet-based services using Smartphone are being revitalized. Smartphone users, opinion experts more than 99 percent of the economically active population is using, it has reached the saturation past the early stages of formation. Smartphone is equipped with a general purpose OS possible the implementation of high performance environment similar level as a personal computer. Also, it is a mobile communication terminal scalable which can be removed or installed various applications. New information technology like Smartphone gives us a very important and interesting research issue that is to find and prove the factors influencing the purchase intention. At this point, study identifying on the influence factors to the behavioral intention of Smartphone is very important. This study was targeted a total of 99 research papers that are setting up the related Smartphone in among the research papers published in domestic academic journals since 2008. Empirical research related behavioral intention using was summarized on the papers 76.

• Journal of Digital Contents Society
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• v.12 no.3
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• pp.361-370
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• 2011

Recent popularity of the smartphone market, with the explosive growth of mobile location-based SNS(Social Network Service), is into the mainstream. SNS aims to cooperate and share information with all users, but mobile SNS is still not easy people with disabilities. In addition to using the Web, it has difficulty to provide an appropriate interface to access such as smartphone for people with disabilities. This paper will specify and analyze the context-awareness technology and SNS function, and study a variety of information that students with disabilities such as time, location and activity states including data collection and analysis of the situation by converting the status information. It has provide that students with disabilities to lead comfortable life in school according to the various types of disabilities, and school information and safety services using mobile location-based SNS.

• 한국HCI학회:학술대회논문집
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• 2008.02c
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• pp.150-151
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• 2008

With the proliferation of vehicles and advancement of Information Technology, the technology of Telematics, which provides valuable services to people by collecting and analyzing the information from drivers, vehicles and Telematics environments (e.g. traffic information, road condition, weather information, etc.), has been a hot research area in IT and automotive recently. As the information technology revolution brings more and more assistance for driver information processing becomes increasing important. Therefore, drivers' workload is very essential factor for safety driving in Telematics environment. For managing drivers' workload effectively, ETRI haven been developing vehicle and driver management system which can collect data from drivers and vehicle in realtime and analyze the data to manage drivers' and vehcles' status since 2007. This technology will apply to commercial vehicle telematics such as texi or truck management system in the future for increasing driving safety. In this presentation, I would like to explain what we had developed so far and discuss future direction.

• Convergence Security Journal
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• v.13 no.4
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• pp.19-25
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• 2013

The increasing demand for fast, flexible and guaranteed Quality of Service (QoS) in core networks has caused to deploy MultiProtocol Label Switching (MPLS) and Generalized MPLS (GMPLS) control plane. In GMPLS control plane, path computation and cooperation processes are one of the crucial element to maintain an acceptable level of service. The Internet Engineering Task Force (IETF) has proposed the Path Computation Element (PCE) architecture. The PCE is a dedicated network element devoted to path computation process and communications between Path Computation Clients (PCC) and PCEs is realized through the PCE Protocol (PCEP). This paper examines the PCE-based path computation architecture to include the design and implementation of PCEP. The functional modules including Finite State Machine (FSM) and related key design issues of each state are presented. In particular we also discuss internal/external protocol interfaces that efficiently control the communication channels.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.31 no.7
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• pp.94-99
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• 2003

For the assessment of combustion stability of a liquid rocket engine, a device called "Pulse Gun" should be developed first, which can induce artificial perturbations that may lead to excitations of pressure oscillations in a combustion chamber. A model chamber has been used for identifying design parameters of a pulse gun that defines its characteristics. Dynamic pressure measurements showed that shock waves generated from pulse guns are axisymmetric around the axis of a pulse gun barrel. Pressure waves perturbed by a pulse gun induce resonant acoustic frequencies of a model chamber. This fact indicates that successful pressure field perturbations of the KSR-III combustion chamber can be performed by a newly developed pulse gun device. A maximum value of dynamic pressure peaks measured at the opposite point against a pulse gun outlet becomes stronger as charge mass of pulse gun powder increases.

• Journal of the Korean Institute of Gas
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• v.19 no.6
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• pp.92-98
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• 2015

Toxic gases are managed by High Pressure Gas Safety Control Act. Toxic Gases are "31 designated species and each gas of which the permissible concentration($LC_{50}$) is equal to or less than 5000 ppm as defined in High Pressure Gas Safety Control Act.". Korean toxic gas usage in accordance with the growth of the electronic industry has increased explosively. The demand of toxic gas research in domestic university laboratories has grown together. But the research associated with toxic gas safety management in the domestic laboratory is nonexistent state. In this study, we identified weak points of toxic gas safety management through a survey of domestic university laboratory facilities. This paper presented toxic gas safety measures in order to overcome those weak points. Also this paper developed a standard checklist to improve and ensure safe management of toxic gas facility in accordance with the proposed measures. This research is to enforce safety management of toxic gas facilities in domestic university laboratory and it will provide safety guidelines for every laboratory.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.37 no.1
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• pp.83-88
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• 2013

Progressive collapse is a chain reaction of failures propagating throughout a portion of a structure that is disproportionate to the original local failure. When column members are subjected to unexpected load (compression load), they will buckle if the applied load is greater than the critical load that induces buckling. The post-buckling strength of the columns will decrease rapidly, but if there is enough residual strength, the members will absorb the potential energy generated by the impact load to prevent progressive collapse. Thus, it is necessary to identify the relationship of the load-deformation of a column member in the progressive collapse of a structure up to final collapse. In this study, we carried out nonlinear FEM analysis and based on deflection theory, we investigated the load-deformation relationship of H-section steel columns when both ends were fixed.

• Convergence Security Journal
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• v.21 no.1
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• pp.3-7
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• 2021

In quantum cryptographic communication based on quantum mechanics, each piece of information is loaded onto individual photons and transmitted. Therefore, it is impossible to eavesdrop on only a part, and even if an intruder illegally intercepts a photon and retransmits it to the recipient, it is impossible to send the same information to the photon by the principle of quantum duplication impossible. With the explosive increase of various network-based services, the security of the service is required to be guaranteed, and the establishment of a quantum cryptographic communication network and related services are being promoted in various forms. However, apart from the development of Quantum Key Distribution (QKD) technology, a lot of research is needed on how to provide network-level services using this. In this paper, based on the quantum encryption device, we propose an integrated data structure for transferring quantum keys between various quantum encryption communication network devices and realizing an encrypted transmission environment.