• Journal of Chest Surgery
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• v.23 no.4
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• pp.720-730
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• 1990

The complicated pulmonary emphysema including “Giant bullae” and spontaneous pneumothorax often involve both lungs, and controversy exists concerning which is the more rational means of surgical treatment-bilateral simultaneous operation or two staged operation. We report three cases of the complicated bilateral bullous emphysema and two cases of bilateral spontaneous pneumothorax treated through median sternotomy. We performed the ligation of bullae, bullectomy, cystectomy, wedge resection, and left lower lobectomy through median sternotomy. No technical problems were encountered through this approach, which provided maximum benefit with one operation In conclusions, median sternotomy may be appropriate for resection of emphysematous bullae, specially in a severe COPD patient who may be poorly tolerated the superimposed loss of respiratory function due to incisional pain, because median sternotomy permit bilateral exploration, minimal impairment of pulmonary function, simultaneous restoration of pulmonary function, less incisional pain than routine lateral thoracotomy.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.11 no.5
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• pp.601-607
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• 2018

Median filtering is a nonlinear method which is known to be effective in removing impulse noise while preserving local image structure relatively well. However, it could still suffer the smearing phenomena of edges and fine details into neighbors due to undesirable influence from the pixels whose values are far off from the true value of the pixel at hand. This drawback mainly comes from the fact that median filters typically employ a regular shape window for collecting the pixels used in the filtering operation. In this paper, we propose a median filtering method which employs an irregular shape filter window in collecting neighboring pixels around the pixel to be denoised. By employing an irregular shape window, we can achieve good noise suppression while preserving image details. Experimental results have shown that our approach is superior to regular window-based methods.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.21 no.46
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• pp.59-72
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• 1998

This study is concerned in manufacturing cell formation with operation sequences. Operation sequences must be reflected for manufacturing cell formation anyway, because the primary aim of cellular manufacturing system is to minimize the inter-cell flows, and inter-cell flows are differed by operation sequences. In this study we propose flow-similarity(FS) of reflecting both inter-machine similarity and direct/indirect flow, and then apply the modified P-median model for grouping machines. We also use machine cell-part handling frequency(CPH) so as to be assigned parts to the machine cells having the most CPH. We confirm this approach through an application example. The performance of this approach(FS-model) is evaluated and compared with P-median model and F-model through computational experiments.

• Journal of Trauma and Injury
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• v.21 no.2
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• pp.136-139
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• 2008

A great variety of penetrating injuries is happening due to the increasing population and violence today. An optimal surgical approach is the key factor for successful repair of a complicated penetrating injury. A 23-year-old woman fell down the stairs from the second floor and received cervico-thoracic penetration injury due to a metalic bar. The metalic bar ruptured the right jugular vein and penetrated the left upper and lower lung. Under cervico-median sternotomy, neck vessels were repaired and the left thorax was successfully entered to repair the damaged lung through the mediastinal pleura. With this approach, the patient's position did not need to be changed during operation, while reduced the operation time compared to the conventional approach (cervical incision and standard thoracotomy).

• Journal of the Korean Statistical Society
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• v.26 no.4
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• pp.445-452
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• 1997

A more generalized version of the information inequality based on diffusivity which is a natural measure of dispersion for median-unbiased estimators developed by Sung et al. (1990) is presented. This non-Bayesian L$_{1}$ information inequality is free from regularity conditions and can be regarded as an analogue of the Chapman-Robbins inequality for mean-unbiased estimation. The approach given here, however, deals with a more generalized situation than that of the Chapman-Robbins inequality. We also develop a Bayesian version of the L$_{1}$ information inequality in median-unbiased estimation. This latter inequality is directly comparable to the Bayesian Cramer-Rao bound due to the van Trees inequality.

• Journal of Korean Society for Quality Management
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• v.18 no.1
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• pp.55-64
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• 1990

• Journal of Chest Surgery
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• v.14 no.3
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• pp.215-217
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• 1981

• Earthquakes and Structures
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• v.3 no.5
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• pp.719-747
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• 2012

In this paper a novel approach is proposed to address the problem of deriving non-stationary stochastic processes which are compatible in the mean sense with a given (target) response (uniform hazard) spectrum (UHS) as commonly desired in the aseismic structural design regulated by contemporary codes of practice. The appealing feature of the approach is that it is non-iterative and "one-step". This is accomplished by solving a standard over-determined minimization problem in conjunction with appropriate median peak factors. These factors are determined by a plethora of reported new Monte Carlo studies which on their own possess considerable stochastic dynamics merit. In the proposed approach, generation and treatment of samples of the processes individually on a deterministic basis is not required as is the case with the various "two-step" approaches found in the literature addressing the herein considered task. The applicability and usefulness of the approach is demonstrated by furnishing extensive numerical data associated with the elastic design UHS of the current European (EC8) and the Chinese (GB 50011) aseismic code provisions. Purposely, simple and thus attractive from a practical viewpoint, uniformly modulated processes assuming either the Kanai-Tajimi (K-T) or the Clough-Penzien (C-P) spectral form are employed. The Monte Carlo studies yield damping and duration dependent median peak factor spectra, given in a polynomial form, associated with the first passage problem for UHS compatible K-T and C-P uniformly modulated stochastic processes. Hopefully, the herein derived stochastic processes and median peak factor spectra can be used to facilitate the aseismic design of structures regulated by contemporary code provisions in a Monte Carlo simulation-based or stochastic dynamics-based context of analysis.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.2 no.3
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• pp.31-38
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• 2009

A process of identifying moving objects from data is typical task in many computer vision applications. In this paper, we propose a motion segmentation method that generally consists from background subtraction and foreground pixel segmentation. The Approximated Median Filter (AMF) was chosen to perform background modelling. To demonstrate the effectiveness of proposed approach, we tested it gray-scale video data as well as RGB color space.

• The Korean Journal of Applied Statistics
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• v.23 no.1
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• pp.151-165
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• 2010

Images are often corrupted by impulse noise due to a noise sensor or channel transmission errors. The filter based on SVM(Support Vector Machine) and the improved adaptive median filtering is proposed to preserve image details while suppressing impulse noise for image restoration. Our approach uses an SVM impulse detector to judge whether the input pixel is noise. If a pixel is detected as a noisy pixel, the improved adaptive median filter is used to replace it. To demonstrate the performance of the proposed filter, extensive simulation experiments have been conducted under both salt-and-pepper and random-valued impulse noise models to compare our method with many other well known filters in the qualitative measure and quantitative measures such as PSNR and MAE. Experimental results indicate that the proposed filter performs significantly better than many other existing filters.