• Maxillofacial Plastic and Reconstructive Surgery
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• 제38권
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• pp.36.1-36.6
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• 2016

Background: Fracture of the zygomaticomaxillary complex (ZMC) is one of the most common facial injuries. A previous study has performed 3D analyses of the parallel and rotational displacements that occur in a fractured ZMC. However, few studies have investigated adequate fixation methods according to these displacements. Here, we assessed whether specific approaches and fixation methods for displacement of ZMC fractures produce esthetic results. Methods: Hospital records and pre- and post-surgical computed tomographic scans of patients treated for ZMC fractures at the Department of Oral and Maxillofacial Surgery, College of Dentistry, Wonkwang University, between January 2010 and December 2015, were selected. Data were analyzed according to the direction of displacement and post-reduction prognosis using a 3D software. Results: With ZMC fractures, displacement in the posterior direction occurred most frequently, while displacement in the superior-inferior direction was rare. A reduction using a transconjunctival approach and an intraoral approach was statistically better than that using an intraoral approach, Gillies approach, and lateral canthotomy approach for a posterior displacement (P < 0.05). Conclusions: When posterior displacement of a fractured ZMC occurs, use of an intraoral approach and transconjunctival approach simultaneously is recommended for reducing and fixing the displaced fragment accurately.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제15권3호
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• pp.171-177
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• 1993

The prominent malar region has been recognized a sign of youth and beauty in caucasian who generally have a dolichocephalic and long face. But in the orients, especially Koreans who generally have a mesocephalic or brachycephalic face, it is considered an agressive, unesthetic facial appearance. So many patients require the shaving of prominent malar eminence and arch, and many methods of its reduction have been devised. For the exposure of malar complex, infraorbital skin incision, intraoral approach, preauricular approach, supraauricular scalp incision, and coronal approach have been used. And for the reduction of bony structure, direct shaving, contouring and repositioning of the malar complex after extirpation, and medially fracture of zygomatic arch have been used with its own merits. We performed the reduction malarplasty through intraoral approach. After two parallel oeteotomy at medial part of the zygomatic bone, the midsegment is removed. The posterior arch of zygoma was bended or green stick fractured. When more correction was required, the posterior arch was fractured medially through the step incision at skin. This method has a some advantages. Compared with the method for extirpation of malar complex, the infection rate is diminished, the resorption is small because of no free bone graft. And cheek drooping is prevented. Compared with the method of coronal approach, the surgical trauma is minimal. Now we report some cases of reduction malarplasty performed through intraoral approach and disscus the surgical technique and results.

• Earthquakes and Structures
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• 제4권4호
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• pp.341-363
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• 2013

Earthquake response calculation, parametric analysis and seismic parameter optimization of base-isolated structures are some critical issues for seismic design of base-isolated structures. To calculate the earthquake responses for such non-symmetric and non-classical damping linear systems and to implement the earthquake resistant design codes, a modified complex mode superposition design response spectrum method is put forward. Furthermore, to do parameter optimization for base-isolation structures, a graphical approach is proposed by analyzing the relationship between the base shear ratio of a seismic base-isolation floor to non-seismic base-isolation one and frequency ratio-damping ratio, as well as the relationship between the seismic base-isolation floor displacement and frequency ratio-damping ratio. In addition, the influences of mode number and site classification on the seismic base-isolation structure and corresponding optimum parameters are investigated. It is demonstrated that the modified complex mode superposition design response spectrum method is more precise and more convenient to engineering applications for utilizing the damping reduction factors and the design response spectrum, and the proposed graphical approach for parameter optimization of seismic base-isolation structures is compendious and feasible.

• 소음진동
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• 제9권1호
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• pp.60-69
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• 1999

In the first paper of this research$^{(1)}$. a new time series method. directional ARMAX (dARMAX) model-based approach. was proposed for rotordynamics identification. The dARMAX processes complex-valued signals, utilizing the complex modal testing theory which enables the separation of the backward and forward modes in the two-sided frequency domain and makes effective modal parameter identification possible. to account for the dynamic characteristics inherent in rotating machinery. In this second part. an evaluation of its performance characteristics based on both simulated and experimental data is presented. Numerical simulations are carried out to show that the method. a complex time series method. successfully implements the complex modal testing in the time domain. and it is superior in nature to the conventional ARMAX and the frequency-domain methods in the estimation of the modal parameters for isotropic and weakly anisotropic rotor systems. Experiments are carried out to demonstrate the applicability and the effectiveness of the dARMAX model-based approach, following the proposed fitting strategy. for the rotordynamics identification.

• 대한기계학회논문집A
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• 제25권8호
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• pp.1235-1241
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• 2001

An engineering estimation equation for the crack opening displacement(COD) is proposed for a complex cracked pipe, based on the reference stress approach. To define the reference stress, a simple plastic limit load analysis for the complex cracked pipe subjected to combined bending and tension is performed considering the crack closure effect in the compressive-stressed region. Comparison with ten published test data and the results from existing method shows that the present method not only reduces non-conservatism associated with the existing method, but also provides consistent and overall satisfactory results.

• Bulletin of the Korean Chemical Society
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• 제32권spc8호
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• pp.3051-3056
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• 2011

We calculate the free energy surfaces for two small proteins and a protein-RNA complex system by using a lattice model approach. In particular, we employ the Munoz-Eaton model, which is a native-structure based statistical mechanical model for studying protein folding problem. The model can provide very useful insights into the folding mechanisms by allowing one to calculate the free energy surfaces efficiently. We first calculate the free energy surfaces of ubiquitin and BBL, using both approximate and recently developed exact solutions of the model. Ubiquitin exhibits a typical two-state folding behavior, while BBL downhill folding in our study. We then extend the method to study of a protein-RNA complex. In particular, we focus on PAZ-siRNA complex. In order to elucidate the interplay between folding and binding kinetics for this system we perform comparative studies of PAZ only, PAZ-siRNA complex and two mutated complexes. We find that folding and binding are strongly coupled with each other and the bound PAZ is more stable than the unbound PAZ. Our results also suggest that the binding sites of the siRNA may serve act as a nucleus in the folding process.

• 대한전기학회논문지:시스템및제어부문D
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• 제49권2호
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• pp.81-87
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• 2000

This paper presents a new approach to the synthesis of two-dimensional arrays such as Atmel 6000 series FPGAs using internal don't cares. Basically complex terms which fits to the linear array of cells without further routing wires are generated and they are collected by OR/XOR operations. In previous methods, complex terms are collected only by XOR operations, which may not be effective for nearly unate functions. In this paper, we allow complex terms to be collected by OR operations in addition to XOR operations. First, complex terms that lies in the ON-set of the function are generated and collected by OR operations. The sub-function realized by the first stage becomes an internal don't cares and they are exploited in the second stage which generates complex terms collectable by XOR operation. Experimental results shows the efficacy of the proposed method compared to the previous methods.

• 대한치과의사협회지
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• 제16권6호통권109호
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• pp.465-476
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• 1978

A roentgenocephalometric approach was performed by the author for the purpose of investigating cranio-facial complex of normal Korean female adults. Thirty roentgenocephalograms of the Korean female adults with normal occlusion among one thousand and two hundreds of samples were selected for this research. Standards of each items of angular and linear measurements on lateral view and linear measurements in P-A view were figured out. In some items, co-relations were traced to search reciprocal relationships. Some of the measurements were compared with other reports.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 1995년도 봄 학술발표회 논문집
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• pp.130-135
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• 1995

Wind-induced vibration of buildings with viscoelastic dampers are studied analytically. The added viscoelastic dampers change the damping distribution and reduce the response of buildings. The distribution of damping resistance that results from these viscoelastic dampers is known as non-classical or non-proportional. Non-classically damped structures are analyzed by state-space approach. However, this approach is complex and time-consumming compared to classical approach. This paper is aimed at the analysis of wind-induced Vibration Of buildings With Viscoelastic dampers. The Process Of State-Space approach is studied and the approximate analysis is suggested to overcome the complex and time-consuming access. For numerical certification, PSDF(Power Spectral Density Function) is obtained. Autocorrelation function is obtained in time domain and PSDF is obtained by fourier transformation of this function in frequency domain. It is found that Approximate method can give close approximation to exact solution.

• Proceedings of the National Institute of Ecology of the Republic of Korea
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• 제1권1호
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• pp.9-21
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• 2020

Ecological communities adapt the concept of informatics in the late 20 century and develop rapidly in the early 21 century to form Ecoinformatics as the new approach of ecological research. The new approach takes into account the data-intensive nature of ecology, the precious information content of ecological data, and the growing capacity of computational technology to leverage complex data as well as the critical need for informing sustainable management of complex ecosystems. It comprehends techniques for data management, data analysis, synthesis, and forecasting on ecological research. The present paper attempts to review the development history, studies and application cases of ecoinformatics in ecological research especially on Long Term Ecological Research (LTER). From the applications show that the ecoinformatics approach and management system have formed a new paradigm in ecological research.