• Earthquakes and Structures
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• 제1권4호
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• pp.327-344
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• 2010

This paper summarizes results of a comprehensive analytical study aimed at evaluating the influence of strong ground motion duration on residual displacement demands of single-degree-of-freedom (SDOF) and multi-degree-of-freedom (MDOF) systems. For that purpose, two sets of 20 earthquake ground motions representative of short-duration and long-duration records were considered in this investigation. While the influence of strong ground motion duration was evaluated through constant-strength residual displacement ratios, $C_r$, computed from the nonlinear response of elastoplastic SDOF systems, its effect on the amplitude and height-wise distribution of residual drift demands in MDOF systems was studied from the response of three one-bay two-dimensional generic frame models. In this investigation, an inelastic ground motion intensity measure was employed to scale each record, which allowed reducing the record-to-record variability in the estimation of residual drift demands. From the results obtained in this study, it was found that long strong-motion duration records might trigger larger median $C_r$ ratios for SDOF systems having short-to-medium period of vibration than short strong-motion duration records. However, taking into account the large record-to-record variability of $C_r$, it was found that strong motion duration might not be statistically significant for most of the combinations of period of vibration and levels of lateral strength considered in this study. In addition, strong motion duration does not have a significant influence on the amplitude of peak residual drift demands in MDOF systems, but records having long strong-motion duration tend to increase residual drift demands in the upper stories of long-period generic frames.

• Ocean Science Journal
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• 제42권1호
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• pp.19-30
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• 2007

This study analyzed the current meter records along with wind records for over 500 days obtained in the Kangjin Bay, South Sea, Korea spanning from March, 2003 to Nov. 2005. Various analyses include descriptive statistics, harmonic analysis of tidal constituents, spectra and coherence, the principal axis, progressive vector diagrams. These analyses can illustrate the response of residual current to the local wind resulting in the net drift with rotational motion. Current speed ranges from -28 to 33 (cm/sec), with standard deviations from 6.5 to 12.9 (cm/sec). The harmonic analyses of the tidal current show the average form number, 0.12 with semi-diurnal type and the rectilinear orientation of the major axis toward northeast. The magnitudes of the semi-major range from 12.7 to 17.7 (cm/sec) for M2 harmonics, while for S2 harmonics, they range from 6.3 to 10.4 (cm/sec), respectively. In the spectral and coherency analysis of residual current and wind, a periodicity of 13.6 (day) is found to be most important in both records and plays an important role in the net drift of residual current. The progressive vector diagrams of residual current and wind show two types of behaviors such as unidirectional drift and rotational motion. It was also found that 3 % rule holds approximately to drive 1 (cm/sec) drift current by 30 (cm/sec) wind speed based on the correlation of the semi-major axis of wind and residual current.

• Journal of Chest Surgery
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• 제33권2호
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• pp.139-145
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• 2000

Background: The purpose of this study is to review the clinical course after the correction of noncomplicated ventricular septal defect and to analyze the morbidity and risk factors of postoperative complications and evaluate residual defect during the follow-up period. Material and Method: From September 1994 to June 1998 24 patients(median age 10 months) underwent surgery under the diagnosis of ventricular septal defect. We made a retrospective review of the clinical records including the operation notes critical care unit records echocardiography results and the follow-up records. Result: There was no early mortality nd late mortality. There was no postoperative complete conduction block. Respiratory complication was the most common complication. The body weight age type of ventricular septal defect associated anomalies and operative procedure were not related to the incidence of complications. residual ventricular septal defects aortic valve regurgitation and tricuspid valve regurgitation were insignificant in postoperative hemodynamics, Conclusions: Correction of the noncomplicated ventricular septal defect was done without mortality and complete heart block. Aggressive preoperative medical treatment and early surgical treatment may decrease postoperative complications. Postoperative residual shunt and tricuspid regurgitation were not problematic during the follow-up

• Asian Pacific Journal of Cancer Prevention
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• 제15권17호
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• pp.7383-7387
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• 2014

Background: To determine rates of residual disease along with influencing factors in women with stage IA to IB1 cervical carcinoma after conization. Materials and Methods: A retrospective study was conducted of medical records of 198 stage IA to IB1 cervical carcinoma patients who had undergoing cervical conization followed by primary surgical treatment during 2006-2013. Independent factors correlating with residual carcinoma in subsequent surgical specimens were analyzed by stepwise regression analysis. Results: Mean age was 48.9 years. Cone specimens demonstrated free margins in 36 women (18.8%). In case of having disease at margin, high-grade cervical intraepithelial neoplasia (CIN) and carcinoma were evidenced in 58 and 97 women, respectively. Pathology of subsequent specimens revealed residual carcinoma in 78 women (39.4%), high-grade CIN or adenocarcinoma in situ (AIS) in 45 (22.7%), and no residual pathology in 75 (37.9%). Age more than 35 years, postmenopausal status, having symptoms, diseases or invasive lesions at conization margins or disease on endocervical aspect, and higher stage were significantly correlated with residual cancer in surgical treatment specimens. On regression analysis, postmenopause and stage were independent factors associated with residual carcinoma.Conclusions: Patient and tumor characteristics are predictive factors for residual cancer in the studied group of women.

• 기록학연구
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• 제47호
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• pp.161-193
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• 2016

청남대는 1983년에 건립되어 2003년까지 대통령 별장으로 사용된 공공건축물이다. 그렇다면 건립과정에서 공공기록물이 생산되었을 것이다. 공공기관의 기록물은 보존기간 동안 관리되다 폐기되는 것이 일반적이다. 그 당시 보존기간표를 고려하면, 청남대 건립 시작부터 완공까지 설명책임성을 보여줄 기록물은 남아 있지 않을 확률이 크다. 그렇지만 보존기간과 상관없이 기록물이 남아 있는 경우도 있으므로 확인해 볼 필요는 있다. 이러한 현실을 감안하여 이 연구는 청남대 건립 관련 기록물의 잔존여부 조사를 목적으로 한다. 이를 위해 건립과정에서 생산되었을 것으로 추정되는 기록물의 목록을 작성하고, 그것을 생산 또는 보존하고 있을 것으로 짐작되는 공공기관에 잔존 기록물이 남아 있는지 확인한다. 그리고 이 결과를 가지고, 기존 공공건축물의 기록물 수집전략을 제언하고, 앞으로 세워질 공공건축물의 기록물 관리에 대한 방향을 제시한다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제13권7호
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• pp.3620-3637
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• 2019

Since the birth of Synthetic Aperture Radar (SAR), it has been widely used in the military field and so on. However, the existence of speckle noise makes a good deal inconvenience for the subsequent image processing. The continuous development of sparse representation (SR) opens a new field for the speckle suppressing of SAR image. Although the SR de-noising may be effective, the over-smooth phenomenon still has bad influence on the integrity of the image information. In this paper, one novel SAR image de-noising method based on residual image fusion and sparse representation is proposed. Firstly we can get the similar block groups by the non-local similar block matching method (NLS-BM). Then SR de-noising based on the adaptive K-means singular value decomposition (K-SVD) is adopted to obtain the initial de-noised image and residual image. The residual image is processed by Shearlet transform (ST), and the corresponding de-noising methods are applied on it. Finally, in ST domain the low-frequency and high-frequency components of the initial de-noised and residual image are fused respectively by relevant fusion rules. The final de-noised image can be recovered by inverse ST. Experimental results show the proposed method can not only suppress the speckle effectively, but also save more details and other useful information of the original SAR image, which could provide more authentic and credible records for the follow-up image processing.

• Journal of Korean Neurosurgical Society
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• 제37권3호
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• pp.179-186
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• 2005

Objective: The purpose of this paper is to report our experiences in managing seventeen cases of residual intracranial aneurysms following surgical or endovascular treatment and discuss the incidence of residual aneurysms, the indications and technique of retreatment of residual aneurysms. Methods: During a period of 42 months, we treated 391 aneurysms in 339 patients with microsurgical clipping or GDC embolization as a primary treatment. In 39 of them, follow-up angiography revealed residual aneurysms and seventeen of whom were retreated. There were eleven cases in ACoA, three cases in distal ICA, one, in each of MCA, ACA and basilar artery. We reviewed retrospectively the clinical notes, operation records and cerebral angiograms of seventeen patients who had been treated for residual aneurysms. Results: Complementary treatment was performed in 8 cases by means of surgery and in 9 cases by means of GDC embolization. There were eleven females and six males with an age variation between 29 and 78 years. The mean duration of angiographic follow-up was 17.3 months. Of the seventeen cases that were treated for residual aneurysms, fourteen achieved complete occlusion. Of 17 retreated patients, fifteen patients had good recovery according to the Glasgow Outcome Scale. Conclusion: When occlusion after endovascular or surgical treatment is incomplete, a new multidisciplinary approach should be carried out. Given our experiences, we recommend coil embolization of the choice in cases that the residual aneurysmal neck had been narrowed by previous clipping. On the other hand, if the residual aneurysm has enough space to clip but not enough to coil, we recommend the microsurgical clipping.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2008년도 정기 학술대회
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• pp.331-336
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• 2008

An self-centering energy-dissipative (SCED) bracing system has recently been developed as a new seismic force resistant bracing system. The advantage of the SCED brace system is that, unlike other comparable advanced bracing systems that dissipate energy, such as the buckling restrained brace system, it has a self-centering capability that reduces or eliminates residual building deformations after major seismic events. In this study seismic performance of SCED braced frames is evaluated for a set of 20 design level earthquake records. According to analysis results the SCED systems showed more uniform interstory drift demand for buildings with 8 story or fewer. The residual deformation in SCED buildings turned out to be much less than that of moment-resisting frames.

• 대한토목학회논문집
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• 제41권5호
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• pp.513-522
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• 2021

스마트폰은 3축 방향 가속도를 기록할 수 있는 MEMS 센서를 포함하고 있고 무선통신망 장치가 내장되어 실시간으로 진동 데이터를 관측하고 전송할 수 있다. 이러한 특징을 기반으로 스마트폰을 지진관측망으로 사용하는 데 큰 장점으로 작용한다. 현재 국내 영남권에 시범적으로 279개의 스마트폰이 설치되어 지진관측망으로 사용되고 있다. 본 연구에서는 스마트폰 관측 지진기록의 유효성을 확인하기 위해 국가지진관측망의 지진관측소 기록과 스마트폰의 관측기록을 비교하였다. 비교에 활용된 데이터는 2019년에 발생한 5개의 지진에 대한 기록이며, 기상청과 한국지질자원연구원의 지진관측소에서 기록한 321개의 데이터와 스마트폰에서 기록한 145개의 데이터이다. 최대지반가속도(PGA)를 추출한 후, 지반운동예측식(GMPE)을 스마트폰 기록에 적용하여 PGA와 최대수평가속도(PHA)의 잔차를 분석하였다. 분석 결과, 스마트폰 MEMS 센서 관측기록의 자연대수 평균 잔차는 0.59로 약 1.8배 큰 PHA를 관측하였다. 또한, 스마트폰 MEMS 센서의 설치 층수가 높아질수록 잔차가 줄어드는 경향을 확인하였는데, 이는 지진파 응답스펙트럼의 경향과 비슷하다.

• Earthquakes and Structures
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• 제11권4호
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• pp.649-664
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• 2016

A seismic damaged bridge may be hit again by a strong aftershock or another earthquake in a short interval before the repair work has been done. However, discussions about the impact of the unrepaired damages on the residual earthquake resistance of a steel bridge are very scarce at present. In this paper, nonlinear time-history analysis of a steel arch bridge was performed using multi-scale hybrid model. Two strong historical records of main shock-aftershock sequences were taken as the input ground motions during the dynamic analysis. The strain response, local deformation and the accumulation of plasticity of the bridge with and without unrepaired seismic damage were compared. Moreover, the effect of earthquake sequence on crack initiation caused by low-cycle fatigue of the steel bridge was investigated. The results show that seismic damage has little impact on the overall structural displacement response during the aftershock. The residual local deformation, strain response and the cumulative equivalent plastic strain are affected to some extent by the unrepaired damage. Low-cycle fatigue of the steel arch bridge is not induced by the earthquake sequences. Damage indexes of low-cycle fatigue predicted based on different theories are not exactly the same.