• 대한두개안면성형외과학회지
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• 제22권2호
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• pp.93-98
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• 2021

Background: Pediatric nasal fractures, unlike adult nasal fractures, are treated surgically as early as 7 days after the initial trauma. However, in some cases, a week or more elapses before surgery, and few studies have investigated the consequences of delayed surgery for pediatric nasal fractures. The purpose of this study was to evaluate the postoperative outcomes of pediatric nasal fractures according to the time interval between the initial trauma and surgery. Methods: The records of pediatric patients under 12 years old who underwent closed reduction of nasal bone fracture from March 2012 to February 2020 were reviewed. The interval between trauma and surgery was divided into within 7 days (early reduction) and more than 7 days (delayed reduction). Postoperative results were classified into five grades (excellent, good, moderate, poor, and very poor) based on the degree of reduction shown on computed tomography. Results: Ninety-eight patients were analyzed, of whom 51 underwent early reduction and 47 underwent delayed reduction. Forty-two (82.4%) of the 51 patients in the early reduction group showed excellent results, and nine (17.6%) showed good results. Thirty-nine (83.0%) of the 47 patients in the delayed reduction group showed excellent results and eight (17.0%) showed good results. No statistically significant difference in outcomes was found between the two groups (chi-square test p= 0.937). However, patients without septal injury were significantly more likely to have excellent postoperative outcomes (chi-square test p< 0.01). Conclusion: No statistically significant difference was found in the outcomes of pediatric nasal fractures between the early and delayed reduction groups. Successful surgical results were found even in patients who received delayed reduction (more than 7 days after trauma).

• 대한두개안면성형외과학회지
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• 제17권2호
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• pp.51-55
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• 2016

Background: Nasal bone fractures are managed by closed reduction within the 2-week period, and are managed by secondary correction after this time. There is little literature on the delayed reduction for nasal bone fractures beyond the 2-week duration. We report our experience with nasal fractures, which were reduced beyond this period. Methods: A retrospective review was performed for all patients who had undergone closed reduction of isolated nasal bone fracture. Patients were included for having undergone reduction of nasal bone fractures at or more than 2 weeks after the injury. Medical records were reviewed for demographic information, injury mechanism, fracture type, delay in treatment, and cause for delay. Postoperative outcomes were evaluated using computed tomography images. Results: The review identified 10 patients. The average reduction time was 22.1 days. Five of patients underwent reduction between days 15 and 20, and the remaining five patients underwent reduction between days 21 and 41. The postoperative outcomes were excellent in 8 patients and good in 2 patients. Conclusion: Outcomes were superior for nasal fractures with displaced end plates and multiple fracture segments. Our study results appears to support delayed reduction of isolated nasal fractures in the presence of factors that delay bony reunion.

• 전자공학회논문지SC
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• 제41권2호
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• pp.29-36
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• 2004

본 논문에서는 시변 시간지연을 갖는 선형시스템의 분수 모델 간략화를 다룬다. 이를 위해 선형 시간지연 시스템의 축소된 소인수 분해를 정의하고 선형 행렬부등식의 해를 이용하여 구한다. 축소된 소인수의 일반화 가제어성, 가관측성 그래미안을 이용하여 시스템의 균형화된 상태공간 모델을 구현한다. 모델 차수축소는 균형화된 상태공간 모델의 일부 상태변수를 절삭하여 얻어지며 모델 오차의 상한치를 제시한다. 제안된 방법의 효용성을 수치 예를 통하여 입증한다.

• Journal of Korean Neurosurgical Society
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• 제60권6호
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• pp.717-722
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• 2017

Objective : To evaluate the effectiveness and efficacy of delayed burr hole surgery in relation to the reduction of postoperative subdural hematoma (SDH) volume in patients with acute SDH. Methods : We retrospectively analyzed patients with acute SDH who received delayed burr hole surgery at our institute. Age, sex, Glasgow coma scale, maximal SDH thickness, volume of SDH, midline shifts, hounsfield unit (HU), and medical history of anticoagulant agent usage were recorded. Outcome measures were delayed operation day, reduction of SDH volume after operation, and the Glasgow outcome scale (GOS) score at discharge. The patients were divided two groups according to the postoperative reduction of volume of SDH (${\geq}50%$, group A; <50%, group B). We also analyzed variables and differences between two groups. Results : Eighteen patients were available for this analysis. The mean delayed of surgery was $13.9{\pm}7.5$ days. Maximal thickness of SDH was changed from $10.0{\pm}3.5mm$ to $12.2{\pm}3.7mm$. Volume of SDH was changed from $38.7{\pm}28.0mL$ to $42.6{\pm}29.6mL$. Midline shifts were changed from $5.8{\pm}3.3mm$ to $6.6{\pm}3.3mm$. HU were changed from $66.4{\pm}11.2$ to $53.2{\pm}20.6$. Post-operative reduction of SDH volume was $52.1{\pm}21.1%$. Eleven patients (61%) had a discharge GOS score of 1 (good recovery). Ten patients (56%) were enrolled in group A. Midline shifting was greater in group A than in group B ($7.4{\pm}3.3$ vs. $3.0{\pm}2.4mm$; p<0.02). The delay of surgery was shorter for group A than group B ($9.2{\pm}2.3$ vs. $19.8{\pm}7.7$ days; p<0.0008). Conclusion : Among well selected patients, delayed burr hole surgery in patients with acute SDH may be effective for reduction of SDH volume. Further studies will be necessary to establish the effectiveness and safety of delayed burr hole surgery in patients with acute SDH.

• 말소리와 음성과학
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• 제4권4호
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• pp.109-115
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• 2012

This paper mainly aims to investigate how differently choral speech and altered auditory feedback (i.e., delayed auditory feedback, frequency-altered feedback) enhance speech fluency during sentence reading. To do this, a stuttering reduction rate was used and measured how much stuttering in frequency was reduced during each of the fluency enhancing conditions (i.e, typical choral reading, DAF, FAF) relative to typical solo reading. The results showed that stuttering frequency was reduced in the three fluency enhancing conditions and the highest mean value in stuttering reduction rate was observed during typical choral reading. Some discussion was provided in relation to the stuttering reduction rate observed during typical choral reading and its further speculation.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• 제4권2호
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• pp.175-180
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• 2001

목적: 공기 정복술은 조작이 간단하고 정복 시간이 빠르며 방사선 노출 시간이 짧고 천공 이환률이 낮다는 장점이 있다. 장중첩증 치료에 정복술에 실패한 경우 수술적 치료를 하게 되는데 대부분은 장절제 없이 단순 도수 정복만으로 치료되는 경우가 많으며 상당수에서는 이미 정복된 상태로 발견되기도 한다. 일차 공기 정복술에 실패한 장중첩증 환자에서 반복 지연 정복술을 시행하여 그 유용성 및 안전성을 알아보고자 본 연구를 시행하였다. 방법: 1998년 1월부터 1999년 12월까지 일차 공기 정복술을 시행하여 실패한 환자 중 복막염, 쇼크, 독성 증상이 없는 임상적으로 안정된 21명을 대상으로 1시간에서 3시간(평균 2.2 시간)후에 이차 지연 정복을 시행하였다. 결과: 정복술 시행 전 환자들의 증상 및 징후의 지속 시간은 6~48시간이었으며 평균 24시간이었다. 일차 정복 후 1~3시간 후(평균 2.2 시간)에 이차 지연 정복술을 시행하였고 76.2% (21례 중 16례)에서 성공적으로 정복되었으며 나머지 5례는 수술적 치료를 하였다. 이중 4례는 도수 정복되었으며 1례는 자연 정복되어 있었다. 결론: 초기 정복에 실패한 장중첩증 환자에서 임상적으로 안정적일 경우 시간 간격을 두고 반복지연 정복술을 시행하는 것은 불필요한 수술의 빈도를 줄일 수 있을 것으로 사료된다.

• Journal of Welding and Joining
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• 제7권2호
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• pp.49-59
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• 1989

The effect of non-metallic inclusions on the HAZ hydrogen induced cracking was investigated. Quench and temper high tensile strength steels containing various sulphur contents were employed. The sulphur contents range between 0.007% and 0.040%. Non-metallic inclusions were mainly MnS type sylphide and Mn-Al-Si type. The sensitivity of HAZ delayed cracking was evaluated by implant testing. Diffusible hydrogen content was varied by controlling the moisture absorbing condition of manual arc welding electrodes. The one was asreceived condition, the other was dipping the electrodes in the water for ten minutes. The main results obtained were as follows; 1) The results of implant test showed that critical stress increased with increasing S content up to 0.013%. But steel containing 0.040%S showed lower critical stress than that of 0.013% S. These result suggest that there will be optimum S content to prevent HAZ delayed cracking of high strength steels. 2) Under the lower D.H.C. level, critical stress was increased with rolling reduction, but higher D.H.C. level, effect of rolling reduction was not recognized.

• International Journal of Fuzzy Logic and Intelligent Systems
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• 제6권3호
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• pp.184-189
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• 2006

This paper deals with a fractional model reduction for T-S fuzzy systems with time varying delayed states. A contractive coprime factorization of time delayed T-S fuzzy systems is defined and obtained by solving linear matrix inequalities. Using generalized controllability and observability gramians of the contractive coprime factor, a balanced state space realization of the system is derived. The reduced model will be obtained by truncating states in the balanced realization and an upper bound of model approximation error is also presented. In order to demonstrate efficacy of the suggested method, a numerical example is performed.

• 전자공학회논문지SC
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• 제40권5호
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• pp.326-332
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• 2003

본 연구에서는 상태변수에 시변 시간지연을 가진 선형시스템의 모델 차수축소를 취급한다. 이를 위하여 시간지연 시스템의 일반화 가제어성/가관측성 그래미안을 선형행렬 부등식의 해를 이용하여 정의하고 균형화된 상태공간 구현을 정의한다. 균형화된 상태공간 구현으로부터 상태변수론 절삭하여 차수축소된 시간지연 시스템을 구하고 모델 축소오차의 상한치를 제시한다. 수치예를 통하여 제시된 방법의 효용성을 입증한다.

• 정보처리학회논문지A
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• 제9A권2호
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• pp.171-180
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• 2002

효과적이고 정확한 데이터 흐름 문제 분석은 흐름그래프와 지배자 트리 그리고 DJ 그래프를 사용한다. 데이터 흐름 문제 해결은 흐름 그래프를 안전하게 지배자 트리로 감축하는 것이다. 흐름 그래프는 파스 트리를 대신하고, DJ 그래프는 감축 가능하거나 감축이 불가능한 흐름 그래프를 지배자 트리로 정확하게 감축하는데 이용된다. 본 연구에서는 Tarjan의 경로 압축 알고리즘을 이용하기 위하여 Top 노드 찾기 알고리즘을 제시하고 기존의 지연감축 알고리즘을 경로압축을 이용하여 개선한다. 경로압축을 이용한 지연감축 알고리즘은 DJ 그래프를 지연 감축하면서 노드를 끌어올려 지배자 트리의 경로를 압축시킨다. 실제로 제안된 알고리즘은 22% 정도 노드들을 끌어올렸고, 20% 정도 경로를 압축시켰다. 압축된 지배자 트리는 효과적인 데이터 흐름 분석을 가능하게 하고, 코드 최적화 과정의 노드 끌어올리기 효과를 가져와 코드 최적화 과정의 복잡도를 개선하는 효과를 가져온다.