• Proceedings of the IEEK Conference
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• 1999.06a
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• pp.958-961
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• 1999

A new image encoding and identification scheme is proposed for security verification by using CGH(computer generated hologram), random phase mask, and correlation technique. The encrypted image, which is attached to the security product, is made by multiplying QPH(quadratic phase hologram) using SA(simulated annealing) algorithm with a random phase function. The random phase function plays a role of key when the encrypted image is decrypted. The encrypted image could be optically recovered by 2-f system and automatically verified for personal identification. Simulation results show the proposed method cand be used for the reconstruction and the recognition of the encrypted. Image.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2004.05a
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• pp.663-668
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• 2004

To model and understand the physics of partial rub, a nonlinear rotor model is investigated by applying nonlinear parameter identification technique to the experimental data. The results show that the nonlinear terms of damping and stiffness should be included to model partial rotor rub. Especially, the impact and friction during the contact between rotor and stator are tried to explain with the nonlinear model on the basis of experimental data. The estimated nonlinear model shows good agreements between numerical and experimental results in its orbit.

• Mass Spectrometry Letters
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• v.15 no.1
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• pp.62-68
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• 2024

The Suspension Trapping (S-Trap) method has been a prominent sample preparation technique since its introduction in 2014. Its capacity to induce protein aggregation using organic solvents has significantly improved protein purification and facilitated peptide identification. However, its full potential for automation has been limited by the lack of a suitable liquid handling system until recently. In this study, we aimed to enhance the automation of S-Trap sample preparation by optimizing the S-Trap digestion process, incorporating triethylammonium bicarbonate (TEAB) and CaCl₂. The utilization of TEAB buffer conditions in this innovative process led to a noteworthy 12% improvement in protein identification. Additionally, through careful observation of various incubation conditions, we streamlined the entire sample preparation workflow into a concise 4 hours timeline, covering reduction, alkylation, and trypsin incubation stages. This refined and expedited automated S-Trap digestion process not only showcased exceptional time efficiency but also improved trypsin digestion, resulting in increased protein identification.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.24 no.6 s.177
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• pp.1633-1642
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• 2000

Like many other mechanical dynamic systems, flexible manipulator systems experience stiction or sticking friction, which may cause input-dependent instabilities. Manipulator performance can be enha nced by identifying friction but it is hard and expensive to measure friction by direct and precise sensing of contact displacements and forces. This study addresses the problem of identifying flexible manipulator joint friction. A dynamic model of a two-link flexible manipulator based upon finite element and Lagrange's method is constructed. The dynamic model includes the effects of joint compliances and actuator dynamics. Friction is also incorporated in the dynamic model to account for stick-slip at the joints. Next, the friction parameters are to be determined. The identification problem is posed as an optimization problem to be solved using nonlinear programming methods. A genetic algorithm is used to increase the convergence rate and the chances of finding the global optimum. The identified friction parameters are experimentally verified and it is expected that the identification technique is applicable to a system parameter identification problem associated with a wide class of nonlinear systems.

• Smart Structures and Systems
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• v.11 no.1
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• pp.19-34
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• 2013

The objective of this paper is to develop on-line system parameter estimation and damage detection technique from the response measurements through using the Recursive Covariance-Driven Stochastic Subspace identification (RSSI-COV) approach. To reduce the effect of noise on the results of identification, discussion on the pre-processing of data using recursive singular spectrum analysis (rSSA) is presented to remove the noise contaminant measurements so as to enhance the stability of data analysis. Through the application of rSSA-SSI-COV to the vibration measurement of bridge during scouring experiment, the ability of the proposed algorithm was proved to be robust to the noise perturbations and offers a very good online tracking capability. The accuracy and robustness offered by rSSA-SSI-COV provides a key to obtain the evidence of imminent bridge settlement and a very stable modal frequency tracking which makes it possible for early warning. The peak values of the identified $1^{st}$ mode shape slope ratio has shown to be a good indicator for damage location, meanwhile, the drastic movements of the peak of $2^{nd}$ mode slope ratio could be used as another feature to indicate imminent pier settlement.

• Journal of information and communication convergence engineering
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• v.21 no.4
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• pp.268-280
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• 2023

Several companies have migrated their existing monolithic web applications to microservice architectures. Consequently, research on the identification of microservices from monolithic web applications has been conducted. Meanwhile, the use-case model plays a crucial role in outlining the system's functionalities at a high level of abstraction, and studies have been conducted to identify microservices by utilizing this model. However, previous studies on microservice identification utilizing use-cases did not consider the components executed in the presentation layer. Unlike existing approaches, this paper proposes a technique that considers all three layers of web applications (presentation, business logic, and data access layers). Initially, the components used in the three layers of a web application are extracted by executing all the scenarios that constitute its use-cases. Thereafter, the usage rate of each component is determined for each use-case and the component is allocated to the use-case with the highest rate. Then, each use-case is realized as a microservice. To verify the proposed approach, microservice identification is performed using open-source web applications.

• The Journal of the Acoustical Society of Korea
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• v.25 no.8
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• pp.375-382
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• 2006

This paper is about how to identify emotional information and how to detect a specific emotion from speech signals. For emotion identification and detection task. we use long-term acoustic feature parameters and select the optimal Parameters using the feature selection technique based on F-score. We transform the conventional SVM into probabilistic output SVM for our emotion identification and detection system. In this paper we propose three approximation methods for log-likelihoods in a hypothesis test and compare the performance of those three methods. Experimental results using the SUSAS database showed the effectiveness of both feature selection and Probabilistic output SVM in the emotion identification task. The proposed methods could detect anger emotion with 91.3% correctness.

• Journal of Internet of Things and Convergence
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• v.8 no.5
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• pp.77-83
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• 2022

Nand flash memory requires an Erase-Before-Write operation structurally. In order to solve this problem, it can be solved by classifying a page (hot data page) where data update operation occurs frequently and storing it in a separate block. The MHF (Multi Hash Function Framework) technique records the frequency of data update requests in the system memory, and when the recorded value exceeds a certain standard, the data update request is judged as hot data. However, the method of simply counting only the frequency of the data update request has a limit in judging it as accurate hot data. In addition, in the case of a technique that determines the persistence of a data update request, the fact of the update request is recorded sequentially based on a time interval and then judged as hot data. In the case of such a persistence-based method, its implementation and operation are complicated, and there is a problem of inaccurate judgment if frequency is not considered in the update request. This paper proposes a lightweight hot data determination technique that considers both frequency and persistence in data update requests.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.30 no.2A
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• pp.161-168
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• 2010

The bonded tendon was adopted to the reactor building of some operating nuclear power plants in Korea and the assessment of the effective prestress force on the bonded tendon is being issued as an important pending problem for continuous operation beyond their design life. The sensitivity analysis of various parameters was carried out to evaluate the effective prestress force using the system identification technique and the optimal parameters were determined for SI technique in this study. The 1/5 scaled post-tensioned concrete beams with the bonded tendon type were manufactured and in order to investigate the relationship of the natural frequency and the displacement to the effective prestress force, impact test, SIMO sine sweep test and bending test using the optical fiber sensor and the compact displacement transducer were carried out. As a result of tests, both the natural frequency and the displacement show the good relationship with the effective prestress force and both parameters are available for the SI technique to estimate the effective prestress force.

• 제어로봇시스템학회:학술대회논문집
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• 1993.10b
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• pp.150-154
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• 1993

A new method is proposed for obtaining Volterra kernals of a nonlinear system by use of a nonlinear systems by use of pseudorandom M-sequences and correlation technique. M-sequence is applied to a nonlinear technique. M-sequence is applied to a nonlinear system and the crosscorrelation function between the input and the output displays not only the linear impulse response of the linear part of the system, but also crosssections of the Volterra kernals of nonlinear system. Simulations are carried out for up to 3rd order Volterra kernal, and the results show a good agreement with the theoretical considerations.