• Journal of Dental Anesthesia and Pain Medicine
• /
• 제16권2호
• /
• pp.117-122
• /
• 2016

Background: The aim of this study was to compare the effectiveness and duration of action of two concentrations of bupivacaine with adrenaline for postoperative pain in patients undergoing surgical removal of four third molars under general anesthesia. Methods: Sixty patients undergoing surgical removal of four wisdom teeth received bupivacaine 0.5% (n = 30) or 0.25% (n = 30). The severity of pain in the immediate recovery period and at 2 and 24 h after surgery was recorded using the visual analogue scale. Differences were assessed by box and whisper plot and the Student's t-test. Results: The analgesic effects of the 0.25% and 0.5% doses were significantly different (P = 0.022) at 30 min after surgery but not after 2 and 24 h. The difference of mean of 0.25% and 0.5% was much higher after 0.5 h but less after 2 and 24 h. Conclusions: Bupivacaine 0.5% was statistically better for pain control during the immediate postoperative period, but there was no significant difference in pain control between the two dose strengths at 2 and 24 h after surgery.

• 대한기관식도과학회지
• /
• 제7권1호
• /
• pp.14-18
• /
• 2001

Background and Objectives： Vegetable Foreign bodies (VFB) in the bronchial tree may be complicated by fragmentation, slippage and impaction during the removal with forceps. This study is to evaluate the safety and efficacy for the technique of removing VFB from the bronchial tree in infants and early childhood using Fogarty balloon catheter. Materials and methods : The subjects consisted of 18 infants and early childhood (7-22 months old) with VFB in the bronchial tree from January 1991 through October 1998. The authors first attempted removal of VFB with forceps and if that failed, removed VFB with Fogarty arterial embolectomy catheter under the ventilating bronchoscopy and general anesthesia. Results: We removed 6 VFB with forceps. could not remove anymore, and so removed 12 VFB with Fogarty catheter. In 8 VFB of less than 24 hours, we could remove 6 VFB with forceps and 2 VFB which could not be removed with forceps were removed with Fogarty catheter. In 10 VFB of more than 24 hours, we could not remove with forceps and removed with Fogarty catheter. Conclusions : VFB in the bronchial tree of infants and early childhood can usually be removed with forceps. But we think that Fogarty balloon catheter technique is a easy, safe method for the removal of bronchial VFB of more than 24 hours, fragmentation, impaction, lower bronchus and too round or slippery to remove with forceps in infants and early childhood.

• Journal of Radiation Protection and Research
• /
• 제43권1호
• /
• pp.20-28
• /
• 2018

Background: Heat energy produced in nuclear reactors and nuclear fuel cycle facilities interactions modifies the physical properties of the shielding materials containing water content. Therefore, in the present paper, effect of the heat on shielding effectiveness of the concretes is investigated for gamma and neutron. The mass attenuation coefficients, effective atomic numbers, fast neutron removal cross-section and exposure buildup factors. Materials and Methods: The mass attenuation coefficients, effective atomic numbers, fast neutron removal cross-section and exposure buildup factors of ordinary and heavy concretes were investigated using NIST data of XCOM program and Geometric Progression method. Results and Discussion: The improvement in shielding effectiveness for photon and reduction in fast neutron for ordinary concrete was observed. The change in the neutron shielding effectiveness was insignificant. Conclusion: The present investigation on interaction of gamma and neutron radiation would be very useful for assessment of shielding efficiency of the concrete used in high temperature applications such as reactors.

• 한국정보통신학회:학술대회논문집
• /
• 한국해양정보통신학회 2009년도 추계학술대회
• /
• pp.574-578
• /
• 2009

정지 영상이나 비디오 영상 시퀀스에서 배경 영상으로부터 움직이는 관심 물체를 구별하기 위한 실시간 물체 검출은 물체의 위치 추적과 인식에 있어 필수적인 단계이다. 물체 분할 후에 그림자 영역이 움직이는 물체 영역에 포함되어지기 때문에 그림자는 물체의 일부분 혹은 움직이는 물체로 오분류될 수 있다. 이러한 이유로 그림자 제거 알고리즘은 움직이는 물체 검출 및 추적 시스템의 결과에 중요한 역할을 한다. 이 문제점들을 해결하기 위해 본 논문에서는 움직이는 물체의 특징과 색상공간에서 그림자의 특징에 기반을 둔 정확한 물체 검출과 그림자 제거 알고리즘을 제안한다. 실험결과는 제안 알고리즘이 실험 영상에서 물체 검출과 그림자 제거에 대해 효과적인 것을 알 수가 있다.

• Clinical Endoscopy
• /
• 제57권4호
• /
• pp.501-507
• /
• 2024

Background/Aims: Polyps greater than 30 mm are classified as "giants". Their endoscopic removal represents a technical challenge. The choice of the endoscopic removal technique is important because it provides a resection sample for precise histopathological staging. This is pivotal for diagnostic, prognostic, and management purposes. Methods: From a retrospective analysis, we obtained a sample of 38 giant polyps. Eighteen polypectomies were performed using the epinephrine volume reduction (EVR) method, nine polypectomies utilized endo-looping or clipping methods, and 11 patients underwent surgery. Results: We obtained en bloc resection with the EVR method in all cases; histology confirmed the correct indication for endoscopic resection in all cases. Moreover, no early or delayed complications were observed, and no patient required hospitalization. Using endo-looping or clipping methods, we observed advanced histology in 1/9 (11.1%) cases, while another patient (1/9, 11.1%) had delayed bleeding. Among patients who underwent surgery, 5/11 (45.5%) were deemed overtreated and three had post-surgical complications. Conclusions: We propose EVR as an alternative technique for giant polyp resection due to its safety, effectiveness, cost-efficiency, and the advantage of avoiding the need to postpone polypectomy to a later time. Further prospective studies might help improve this experience and enhance the technique.

• 한국멀티미디어학회논문지
• /
• 제16권6호
• /
• pp.756-763
• /
• 2013

도메인 필터 및 레인지 필터, 이들 두개의 가우시안 필터에 의해 동작하는 양방향 필터 (bilateral filter)는 원 영상의 선예도 상승 및 노이즈 감소 특성을 가지는 비선형 필터이다. 본 논문은 적외선 소형 표적 탐지에 있어서 양방향 필터을 표적이 없는 경우의 배경을 예측하는 배경 예측기로 설계하고자 한다. 이를 위하여 양방향 필터의 도메인 필터 및 레인지 필터의 표준 편차는 배경 영역과 표적 영역 사이에서 적응적으로 가변되어야 한다. 제안한 양방향 필터는 국부 창 주위 블록에 대하여 그 평균값들의 분산 특성을 이용하여 도메인 필터 및 레인지 필터의 표준 편차를 적응적으로 가변시킨다. 또한 처리되는 화소에 대하여 주위 블록 평균값들의 분산값이 작을 경우 평탄 배경 및 표적 영역으로 분류하고, 그 분산값이 클수록 에지 영역으로 분류하여 양방향 필터 처리함으로써 배경 예측의 정확도를 향상시켰다. 이러한 필터 구조의 양방향 필터는 표적이 없는 경우의 배경을 예측하여 표적을 포함하는 원 영상과 표적이 없는 경우의 예측 배경과의 차를 이용하여 소형 표적을 검출할 수 있다. 실험 결과에서 제안한 양방향 필터를 이용한 방법이 기존의 방법들보다 표적 검출률이 우수함을 확인하였다.

• 한국해양학회지:바다
• /
• 제24권1호
• /
• pp.64-78
• /
• 2019

2016~2017년 '국가해양생태계 종합조사(연안생태계)'에서 얻어진 495개의 퇴적물 중금속 자료를 이용하여 한반도 연안 퇴적물의 중금속 배경농도를 산정하고 오염도를 평가하였다. 퇴적물 입도를 나타내는 지시자로 Al, Cs, Li이 적절하였으며, 이 들과 중금속 농도 사이의 관계에서 이상치 제거 및 잔차 분석을 통하여 가장 낮은 기울기의 자료를 선택하여 중금속과 지시자 사이의 회귀 직선으로 배경농도를 표시하였다. 기존 연구에서의 배경농도와 본 연구의 결과는 비교적 잘 일치하였으며, 본 연구에서는 As 및 Cd에 대해 처음으로 제시하였고, 지시자로 Li을 사용한 배경농도 식을 처음으로 제시하였다.

• 한국연소학회지
• /
• 제17권3호
• /
• pp.30-45
• /
• 2012

An existing unit of power plant is considered to refurbish it for possible application of carbon capture and storage(CCS). Conceptual design of the plant includes basic considerations on the national and international situation of energy use, environmental concerns, required budget, and time schedule as well as the engineering concept of the plant. While major equipment of the recently upgraded power plant is going to be reused, a new boiler for air-oxy fired dual mode operation is to be designed. Cryogenic air separation unit is considered for optimized capacity, and combustion system accommodates flue gas recirculation with multiple cleaning and humidity removal units. The flue gas is purified for carbon dioxide separation and treatment. This paper presents the background of the project, participants, and industrial background. Proposed concept of the plant operation is discussed for the possible considerations on the engineering designs.

• Journal of Information Processing Systems
• /
• 제10권1호
• /
• pp.55-68
• /
• 2014

Automatic segmentation of foreground text from the background in degraded document images is very much essential for the smooth reading of the document content and recognition tasks by machine. In this paper, we present a novel approach to the binarization of degraded document images. The proposed method uses a new local contrast feature extracted based on the stroke width of text. First, a pre-processing method is carried out for noise removal. Text boundary detection is then performed on the image constructed from the contrast feature. Then local estimation follows to extract text from the background. Finally, a refinement procedure is applied to the binarized image as a post-processing step to improve the quality of the final results. Experiments and comparisons of extracting text from degraded handwriting and machine-printed document image against some well-known binarization algorithms demonstrate the effectiveness of the proposed method.

• 한국정밀공학회:학술대회논문집
• /
• 한국정밀공학회 1994년도 추계학술대회 논문집
• /
• pp.108-112
• /
• 1994

The paper describes the effects of magnetic field on the electrochemical polishing process in the view of ionic in the electrolyte. Theoretical background was suggested how magnetic field increases the material removal efficiency and surface finishing ability Magnetic field changes the jonic movement in the electrolyte from linear motion to curved or complex oscillating one, thus increases the electrolytic current density and, as the results, the finishing efficiency.