• Geotechnical Engineering
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• v.4 no.2
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• pp.15-24
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• 1988

To identify the stability of cantilever retaining wall in safe state by the deterministic method, these potential modes of such geotechnical failures as bearing capacity, horizontal sliding and overturning are analysed using Advanced First Order Second Moment (AFOSM) method. All design variables are assumed of the normal distribution and to be statistically independent. Considering the correlations between the single modes, structural system reliability index is 2. 05. Even if the safety factors are larger than the required value in the codes' by the conventional deterministic method, the system reliability of this structure may not be Judged to be safe state since the system reliability index is much lower than general value of 3.

• ETRI Journal
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• v.28 no.5
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• pp.668-671
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• 2006

In this letter, an adaptive scanning that improves intra coding efficiency in the H.264/AVC standard is proposed. The proposed adaptive scanning utilizes the prediction directions (modes) that include the horizontal and vertical edge information in a block. Depending on the prediction directions, the proposed method uses three scanning methods: zigzag scanning, horizontal scanning, and vertical scanning. In the proposed method, horizontal and vertical scanning are used in vertical and horizontal prediction modes, respectively, and the normal zigzag scanning in the H.264 standard is used in all other intra prediction modes. The proposed method reduces the bit rate by approximately 2.5% compared with H.264/AVC, without the degradation of video quality.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2001.11b
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• pp.1370-1375
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• 2001

Substructure coupling or component mode synthesis may be employed in the solution of dynamic problems for structure. The model is partitioned into several subdomains. and a generalized Craig-Bampton representation is derived. In this paper the mode sets(normal modes. constraint modes) have been employed for model reduction. A generalized model reduction procedure has been described. Those reduction methods which adapt constraint modes have been described in detail. As examples. a flexible structure and a 10 DOF damped system are analyzed. Comparison with a conventional reduction method based on a complete model has been made via eigenpairs and dynamic responses.

• Journal of KSNVE
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• v.9 no.2
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• pp.401-408
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• 1999

A method is presented for the vibration analysis of steam turbine-generator rotor system based on the component mode synthesis method. The motion of each component of the system is described by superposing constraint mode associated with boundary coordinates and constrained normal modes associated with internal coordinates. This method using real fixed-interface modes allows for significant reduction in system model size while retaining the essential dynamic characteristics of the lower modes. The capability of this method is demonstrated in the natural frequency and unbalance response analysis of the steam turbine-generator rotor system in which the dynamics of the pedestal is considered. The results by the present method are compared with finite element method and trnasfer matrix method in terms of the accuracy and computing time.

• Journal of Information Processing Systems
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• v.19 no.6
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• pp.858-869
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• 2023

As one of the pivotal techniques of image restoration, single-channel blind source separation (SCBSS) is capable of converting a visual-only image into multi-source images. However, image degradation often results from multiple mixing methods. Therefore, this paper introduces an innovative SCBSS algorithm to effectively separate source images from a composite image in various mixed modes. The cornerstone of this approach is a novel triple generative adversarial network (TriGAN), designed based on dual learning principles. The TriGAN redefines the discriminator's function to optimize the separation process. Extensive experiments have demonstrated the algorithm's capability to distinctly separate source images from a composite image in diverse mixed modes and to facilitate effective image restoration. The effectiveness of the proposed method is quantitatively supported by achieving an average peak signal-to-noise ratio exceeding 30 dB, and the average structural similarity index surpassing 0.95 across multiple datasets.

• International Journal of Aeronautical and Space Sciences
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• v.18 no.1
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• pp.28-37
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• 2017

Recent modeling of thermal nonequilibrium processes in simple molecules like hydrogen and nitrogen has indicated that rotational nonequilibrium becomes as important as vibrational nonequilibrium at high temperatures. In the present work, in order to analyze rovibrational nonequilibrium, the rotational mode is separated from the translational-rotational mode that is usually considered as an equilibrium mode in two- and multi-temperature models. Then, the translational, rotational, and electron-electronic-vibrational modes are considered separately in describing the thermochemical nonequilibrium of nitrogen behind a strong normal shock wave. The energy transfer for each energy mode is described by recently evaluated relaxation time parameters including the rotational-to-vibrational energy transfer. One-dimensional post-normal shock flow equations are constructed with these thermochemical models, and post-normal shock flow calculations are performed for the conditions of existing shock-tube experiments. In comparisons with the experimental measurements, it is shown that the present thermochemical model is able to describe the rotational and electron-electronic-vibrational relaxation processes of nitrogen behind a strong shock wave.

• Proceedings of the PSK Conference
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• 2003.04a
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• pp.276.2-276.2
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• 2003

Simultaneous enantioseparation of nine racemic non-steroidal antiinflammatory drugs (NSAIDs) for their accurate chiral discrimination was achieved by cyclodextrin (CO) modified capillary electrophoresis in the normal polarity (NP) mode and in the reversed polarity (RP) mode. The NP mode employed neutral tri-O-methyl-${\beta}$-cyclodextrin (TM${\beta}$CD) as a selector dissolved in MES buffer (PH 6.0). (omitted)

• Structural Engineering and Mechanics
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• v.39 no.1
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• pp.47-75
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• 2011

An accurate substructural synthesis method including random responses synthesis, frequency-response functions synthesis and mid-order modes synthesis is developed based on rigorous substructure description, dynamic condensation and coupling. An entire structure can firstly be divided into several substructures according to different functions, geometric and dynamic characteristics. Substructural displacements are expressed exactly by retained mid-order fixed-interfacial normal modes and residual constraint modes. Substructural interfacial degree-of-freedoms are eliminated by interfacial displacements compatibility and forces equilibrium between adjacent substructures. Then substructural mode vibration equations are coupled to form an exact-condensed synthesized structure equation, from which structural mid-order modes are calculated accurately. Furthermore, substructural frequency-response function equations are coupled to yield an exact-condensed synthesized structure vibration equation in frequency domain, from which the generalized structural frequency-response functions are obtained. Substructural frequency-response functions are calculated separately by using the generalized frequency-response functions, which can be assembled into an entire-structural frequency-response function matrix. Substructural power spectral density functions are expressed by the exact-synthesized substructural frequency-response functions, and substructural random responses such as correlation functions and mean-square responses can be calculated separately. The accuracy and capacity of the proposed substructure synthesis method is verified by numerical examples.

• The Transactions of the Korean Institute of Power Electronics
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• v.23 no.2
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• pp.86-93
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• 2018

In this work, control methods and operating modes are proposed to manage standalone microgrid. A standalone microgrid generally consists of two sources, namely, battery energy storage system (BESS) and diesel generator (DG). BESS is the main source that supplies active and reactive power regardless of load conditions, whereas DG functions as an auxiliary power source. BESS operates in a constant voltage constant frequency (CVCF) control, which includes proportional-integral + resonant controller in a parallel structure. In CVCF control, the concept of fundamental positive and negative transformation is utilized to generate a three-phase sinusoidal voltage under imbalanced load condition. Operation modes of a standalone microgrid are divided into three modes, namely, normal, charge, and manual modes. To verify the standalone microgrid along with the proposed control methods, a demonstration site is constructed, which contains 115 kWh lead-acid battery bank, 50 kVA three-phase DC - AC inverter, and 50 kVA DG and controllable loads. In the CVCF control, the total harmonic distortion of output voltage is improved to 1.1% under imbalanced load. This work verifies that the standalone microgrid provides high-quality voltage, and three operation modes are performed from the experimental results.

• Journal of KSNVE
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• v.9 no.1
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• pp.196-205
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• 1999

The existence. bifurcation. and the orbital stability of periodic motions, which is called nonlinear normal mode, in a nonlinear dual mass Hamiltonian system. which has 6th order homogeneous polynomial as a nonlinear term. are studied in this paper. By direct integration of the equations of motion. Poincare Map. which is a mapping of a phase trajectory onto 2 dimensional surface in 4 dimensional phase space. is obtained. And via the Birkhoff-Gustavson canonical transformation, the analytic expression of the invariant curves in the Poincare Map is derived for small value of energy. It is found that the nonlinear system. which is considered in this paper. has 2 or 4 nonlinear normal modes depending on the value of nonlinear parameter. The Poincare Map clearly shows that the bifurcation modes are stable while the mode from which they bifurcated out changes from stable to unstable.