• Journal of the Society of Naval Architects of Korea
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• v.43 no.1 s.145
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• pp.50-58
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• 2006

Free running model tests gives us only maneuvering indices not hydrodynamic derivatives. For this reason, system identification method has been applied to the measured data to identify mathematical model describing hydrodynamic force. However It is difficult to obtain complete set of maneuvering derivatives because of strong correlation of sway velocity and yaw rate. Therefore, in this paper, we assumed that sway velocity related coefficients would be obtained by oblique towing test. and then proposed new procedure to estimate yaw related coefficients. To do this, correlation and regression analyses were carried out to establish modified model and estimate maneuvering derivatives. Also D-optimal rudder input scenario was found based on the modified model and confirmed the validity of its sufficient richness as a input scenario.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.42 no.4 s.304
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• pp.35-44
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• 2005

Face recognition out of biometrics is considerable interesting due to high performance and accessibility in applications to security such as access control and banking service. Therefore, a study on the protocol of the performance test is an important issue to understand the art-of state and to show a direction in future works, in addtion to developing algorithms. We present a design criterion for the performance test protocol of face recognition system and show the result of experiment executed on identification and verification scenario based on PCA algorithm and XM2VTS DB

• The Journal of Korean Institute of Communications and Information Sciences
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• v.33 no.8A
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• pp.805-814
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• 2008

Both EPCglobal Generation-2 (Gen2) for passive RFID systems and Intelleflex for semi-passive RFID systems use probabilistic slotted ALOHA with Q algorithm, which is a kind of dynamic framed slotted ALOHA (DFSA), as the tag anti-collision algorithm. A better tag anti-collision algorithm can reduce collisions so as to increase the efficiency of tag identification. In this paper, we introduce and analyze the estimation methods of the number of slots and tags for DFSA. To increase the efficiency of tag identification, we propose two new tag anti-collision algorithms, which are Chebyshev's inequality (CHI) algorithm and hybrid Q algorithm, and compare them with the conventional Q algorithm and adaptive adjustable framed Q (AAFQ) algorithm, which is mentioned in Part I. The simulation results show that AAFQ performs the best in Gen2 scenario. However, in Intelleflex scenario the proposed hybrid Q algorithm is the best. That is, hybrid Q provides the minimum identification time, shows the more consistent collision ratio, and maximizes throughput and system efficiency in Intelleflex scenario.

• Journal of the Korean Society of Safety
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• v.14 no.2
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• pp.62-69
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• 1999

The quantitative risk assessment and consequence analysis by accident scenario in the process of EPS(Expendable Poly Stylene) reaction process are conducted. And the decision making process is studied followed by selecting various alternatives to safety management and facility improvement. The result are as follows; 1) The object of decision making through comprehensive risk assessment are the scenario which can cause four major accident, which are made by process analysis, work analysis and hazard identification. 2) Frequency analysis of ETA, FTA, HRA and consequence analysis of accident to each have been conducted. The each frequency values are yielded $9.2{\times}10_{-5}/yr$ to scenarios $1, 8.2{\times}10^{-4}/yr$ to scenario 2, $4.5{\times}10^{-6}/yr$ scenario 3 and $1.8{\times}10^{-7}/yr$ to scenario 4. The each scenarios have been conducted consequence analysis. 3) The calculated values have been obtained 4.00 to scenario 1, 3.25 to scenario 2, 2.43 to scenario 3 and 1.34 to scenario 4, as the weight value had been applied to the quantitative and normalized criteria of all components. As a risk criteria, scenario 1 have been selected, which is the most dangerous scenario as a result of ranking the scenario. 4) According to the importance of FTA and contribute to scenario 1, the cost-benefit values are yielded $8.05\times10^5[￦/yr]$ to final alternative(Al), $1.55{\times}10^5[￦/yr]$ to final alternative(A2) and $2.32{\times}10^5[￦/yr]$ to final alternative(A3). As a result of final alternative(Al) has been selected, which is the most optimized alternative.

• International Journal of Computer Science & Network Security
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• v.21 no.8
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• pp.55-64
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• 2021

In the last few years, the massive development in wireless networks, high internet speeds and improvement in car manufacturing has shifted research focus to Vehicular Ad-HOC Networks (VANETs). Consequently, many related frameworks are explored, and it is found that security is the primary issue for VANETs. Despite that, a small number of research studies have taken into consideration the identification of performance standards and parameters. In this paper, VANET security frameworks are explored, studied and analysed which resulted in the identification of a list of performance evaluation parameters. These parameters are defined and categorized based on the nature of parameter (security or general context). These parameters are identified to be used by future researchers to evaluate their proposed VANET security frameworks. The implementation paradigms of security frameworks are also identified, which revealed that almost all research studies used simulation for implementation and testing. The simulators used in the simulation processes are also analysed. The results of this study showed that most of the surveyed studies used NS-2 simulator with a percentage of 54.4%. The type of scenario (urban, highway, rural) is also evaluated and it is found that 50% studies used highway urban scenario in simulation.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.14 no.9
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• pp.3858-3869
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• 2020

In this paper, we propose a hash-chain based friendly force identification protocol for personal combatants equipped with a personal combat system in a tactical wireless network. It is imperative in military operations to effectively and quickly identify friendly forces. If the identification of friendly forces is not correct, this can cause friendly fire. In current ground operations, the identification of friendly forces by personal combatants is neither secure nor safe. To address this issue, the proposed protocol uses a hash-chain to determine if a detected person is friendly. Only friendly forces with the same materials that are assigned before they deploy can construct an initial hash-chain. Moreover, the hash-chain is changed at specific times. The performance of the proposed protocol is evaluated on the assumption that the secret key is leaked, which is the worst scenario in the security research field. We verify that the proposed protocol is secure for the various attack scenarios, such as message replay attack, fabrication attack, and Denial of Service attack.

• Journal of Radiation Protection and Research
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• v.26 no.3
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• pp.197-201
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• 2001

A risk analysis consists of a triplet, , where Si is the scenario identification; Pi is the probability of each scenario; and Xi is the consequences of each scenario. A new computing framework, OMAM (ORIGEN-MAAP4-MMCS), has been developed and applied for assessing the risk of a reference plant as well as radiation source terms using the concept of risk triplet. The result of this study using the OMAM framework presented in this paper, can contribute to producing domestic nuclear power plant's risk data base as well as to establishing severe accident management plans.

• The Journal of Society for e-Business Studies
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• v.15 no.4
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• pp.79-99
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• 2010

As data exchange between business partners in e-business becomes more active, obtaining and managing reliable data is emerging as a pressing issue for corporations and organizations. For the resolution of data quality, this paper proposes a framework for data quality management with its scenario. The data quality management framework consists of three phases: data quality monitoring, data quality improvement and data application, each of which has three processes. In each process, necessity, functions, roles, and relationships among processes are specified. In order for users to directly apply the framework to the business field, a business scenario is given with examples of product identification and classification code systems widely used in e-business.

• Nuclear Engineering and Technology
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• v.51 no.1
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• pp.104-115
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• 2019

Since the Fukushima Daiichi accident, there has been an emphasis on the risk resulting from multi-unit accidents. Human reliability analysis (HRA) is one of the important issues in multi-unit probabilistic safety assessment (MUPSA). Hence, there is a need to properly identify all the human and organizational factors relevant to a multi-unit incident scenario in a nuclear power plant (NPP). This study identifies and categorizes the human and organizational factors relevant to a multi-unit incident scenario of NPPs based on a review of relevant literature. These factors are then analyzed to ascertain all possible unit-to-unit interactions that need to be considered in the multi-unit HRA and the pattern of interactions. The human and organizational factors are classified into five categories: organization, work device, task, performance shaping factors, and environmental factors. The identification and classification of these factors will significantly contribute to the development of adequate strategies and guidelines for managing multi-unit accidents. This study is a necessary initial step in developing an effective HRA method for multiple NPP units in a site.

• Computers and Concrete
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• v.20 no.5
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• pp.617-625
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• 2017

Prestress force identification (PFI) is crucial to maintain the safety of prestressed concrete bridges. A synergic identification method has been proposed recently by the authors that can determine the prestress force (PF) and the excitation force simultaneously in prestressed concrete beams with good accuracy. In this paper, the ability of this method in the application with prestressed concrete box-girder bridges is demonstrated. A reasonable assumption is made to capture the similarity of the dynamic behavior of the prestressed concrete box-girder bridge and a beam under a certain loading scenario, and the feasibility of this method for application in a prestressed box-girder bridge is affirmed. A comprehensive laboratory test program is conducted, and the effects of PF, excitation, measuring time and uncertainties are studied. Results show that the proposed method can predict the PF and the excitation force in a prestressed concrete box-girder accurately and has a great robustness against uncertainties.