• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume I
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• pp.260-262
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• 2006

One of future remote sensing techniques for transportation application is vehicle detection from the space, which could be the basis of measuring traffic volume and recognizing traffic condition in the future. This paper introduces an approach to vehicle detection using image object segmentation approach. The object-oriented image processing is particularly beneficial to high-resolution image classification of urban area, which suffers from noisy components in general. The project site was Dae-Jeon metropolitan area and a set of true color aerial images at 10cm resolution was used for the test. Authors investigated a variety of parameters such as scale, color, and shape and produced a customized solution for vehicle detection, which is based on a knowledge-based hierarchical model in the environment of eCognition. The highest tumbling block of the vehicle detection in the given data sets was to discriminate vehicles in dark color from new black asphalt pavement. Except for the cases, the overall accuracy was over 90%.

• 정보처리학회논문지B
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• 제9B권2호
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• pp.231-236
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• 2002

유효한 무성음이 시스템 노이즈와 합성됐을 경우 유효한 무성음 추출에 많은 어려움이 있으나 본 논문에서는 유효한 무성음 추출에 있어 이산 웨이브렛 변환을 이용한 신호 해석 내용을 기반으로 주파수와 그 위치를 블록별로 머징 규칙으로 유효 여부를 결정하기 때문에 노이즈가 많은 환경에서도 유효한 무성음 추출이 가능하다. 머징 알고리즘은 음성만으로도 처리 매개변수를 결정할 수 있고 시스템 잡음에 대하여서도 독립적이기 때문에 유효한 음성을 추출하는데 매우 효과적이다. 실험 결과를 통하여 유효한 음성 추출 처리 과정에서 보다 향상된 결과를 보이고 있으며 특히 고주파 노이즈에 대한 강한 적응력을 제시하고 시스템 구현에도 용이한 시스템 튜닝을 가능케 한다.

• Journal of Welding and Joining
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• 제16권3호
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• pp.64-73
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• 1998

This paper is concerned with defects detection and evaluation of heat affected zone (HAZ) in austenitic stainless steel type 304 by ultrasonic wave and neural network. In experiment, the reflected ultrasonic defect signals from artificial defects (side hole, vertical hole, notch) of HAZ appears as beam distance of prove-defect, distance of probe-surface, depth of defect-surface on CRT. For defect classification simulation, neural network system was organized using total results of ultrasonic experiment. The organized neural network system was learned with the accuracy of 99%. Also it could be classified with the accuracy of 80% in side hole, and 100% in vertical hole, 90% in notch about ultrasonic pattern recognition. Simulation results of neural network agree fairly well with results of ultrasonic experiment. Thus were think that the constructed system (ultrasonic wave - neural network) in this work is useful for defects dection and classification such as holes and notches in HAZ of austenitic stainless steel 304.

• 한국가스학회지
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• 제17권5호
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• pp.42-50
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• 2013

급속한 산업발전과 더불어 전 세계적으로 약 10만 여종의 산업용 물질이 사용되고 있으며, 매년 2,000여종의 신규물질이 개발되고 있다. 이러한 물질들은 인류문화 발전에 크게 기여하고 있지만 일부 물질들은 유해, 위험성 등의 잠재적인 위험성을 가지고 있다. 우리나라는 세계 7대 화학제품 생산국가로, 활발한 수출 입을 통해 국가부흥에 기여하고 있다. 최근 REACH 및 GHS와 같은 화학물질 안전관리에 대한 국제적 관심이 증대되어 그에 따른 효율적인 화학물질 관리체계 구축에 대한 필요성이 커지고 있다. 본 연구에서는 화학물질에 대한 국내, UN GHS 물리화학적 위험성 분류기준, 표지 및 위험성 평가 시험방법, 위험물안전관리법 등에서 정한 분류정보의 차이점을 비교하였으며, 또한 국제 환경변화에 대응하기 위하여 선택가능방식(building block approach)으로 GHS제도 도입방안을 제시하였다. 또한 소비자에게 화학물질의 통일화된 위험성 정보를 제공하여 산업체가 화학물질을 해외로 수출 입 하는데 무역장벽을 해소하고자 하였다.

• 인터넷정보학회논문지
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• 제23권5호
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• pp.79-85
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• 2022

이상 탐지는 일반적인 사용자들의 데이터 집합 속에서 비정상적인 데이터 흐름을 파악하여 미리 차단하는 방법이다. 기존에 알려진 방식은 이미 알려진 공격의 시그니처를 활용하여 시그니처 기반으로 공격을 탐지 및 방어하는 방식인데, 이는 오탐율이 낮다는 장점이 있지만 제로 데이 취약점 공격이나 변형된 공격에 대해서는 매우 취약하다는 점이 문제점이다. 하지만 이상 탐지의 경우엔 오탐율이 높다는 단점이 존재하지만 제로 데이 취약점 공격이나 변형된 공격에 대해서도 식별하여 탐지 및 차단할 수 있다는 장점이 있어 관련 연구들이 활발해지고 있는 중이다. 본 연구에서는 이 중 이상 탐지 메커니즘에 대해 다뤘다. 앞서 말한 단점인 높은 오탐율을 보완하며 그와 더불어 이상 탐지와 분류를 동시에 수행하는 새로운 메커니즘을 제안한다. 본 연구에서는 여러 알고리즘의 특성을 고려하여 5가지의 구성으로 실험을 진행하였다. 그 결과로 가장 우수한 정확도를 보이는 모델을 본 연구의 결과로 제안하였다. Extra Tree와 Three layer ANN을 동시에 적용하여 공격 여부를 탐지한 후 공격을 분류된 데이터에 대해서는 Extra Tree를 활용하여 공격 유형을 분류하게 된다. 본 연구에서는 NSL-KDD 데이터 세트에 대해서 검증을 진행하였으며, Accuracy는 Normal, Dos, Probe, U2R, R2L에 대하여 각각 99.8%, 99.1%, 98.9%, 98.7%, 97.9%의 결과를 보였다. 본 구성은 다른 모델에 비해 우수한 성능을 보였다.

• The Korean Journal of Pain
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• 제29권1호
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• pp.3-11
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• 2016

A nerve block is an effective tool for diagnostic and therapeutic methods. If a diagnostic nerve block is successful for pain relief and the subsequent therapeutic nerve block is effective for only a limited duration, the next step that should be considered is a nerve ablation or modulation. The nerve ablation causes iatrogenic neural degeneration aiming only for sensory or sympathetic denervation without motor deficits. Nerve ablation produces the interruption of axonal continuity, degeneration of nerve fibers distal to the lesion (Wallerian degeneration), and the eventual death of axotomized neurons. The nerve ablation methods currently available for resection/removal of innervation are performed by either chemical or thermal ablation. Meanwhile, the nerve modulation method for interruption of innervation is performed using an electromagnetic field of pulsed radiofrequency. According to Sunderland's classification, it is first and foremost suggested that current neural ablations produce third degree peripheral nerve injury (PNI) to the myelin, axon, and endoneurium without any disruption of the fascicular arrangement, perineurium, and epineurium. The merit of Sunderland's third degree PNI is to produce a reversible injury. However, its shortcoming is the recurrence of pain and the necessity of repeated ablative procedures. The molecular mechanisms related to axonal regeneration after injury include cross-talk between axons and glial cells, neurotrophic factors, extracellular matrix molecules, and their receptors. It is essential to establish a safe, long-standing denervation method without any complications in future practices based on the mechanisms of nerve degeneration as well as following regeneration.

• 수산해양기술연구
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• 제43권1호
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• pp.1-11
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• 2007

It is the basic studies for productivity improvement and laborsaving of purse seine fishery. Because the seine shape is apt to be transformed in seine shooting process due to the effect of tide, this study is intended to establish 4 steps, whose flow velocity are 0, 2, 4 and 6cm/sec, in flume tank and perform the experiment to review the character. We used two model seines designed on the scale of 1 to 180 based on the power block seine, which is the mackerel purse seine generally used in the near sea of Jeju Island and triplex seine, which is the mackerel purse seine of one boat system fishing expected in the future, for the experiment, analyzed of the sinking movements on the two seines and its results are as follows. In the setting over the flow velocity 6cm/sec, experiment was impossible because of flying and transformation of seine were severe. The sinking movements of P seine and T seine generally showed linear phenomenon and the sinking speed showed gentle curve shape. Sinking tendency was distinguished by existence of flow velocity. When there is flow velocity, it showed the phenomenon that it sinking by similar type. Although sinking depth and sinking speed did not show distinguished classification, P seine shows bigger than T seine. When there was in flow velocity, the elapsed time(Et) and sinking depth (PDp, TDp) of P seine and T seine can be shown such experimental equations as PDp=(0.21V+4.96)Et-(0.62V-0.10) and TDp=(0.19V+4.95)Et-(0.72V+0.34). When there was in flow velocity, the elapsed time and siking speed (PSp, TSp) of P seine and T seine can be shown such experimental equations as $PSp=-0.11Et^2+1.42Et+1.75\;and\;TSp=-0.11Et^2+1.41Et+1.37$.

• 한국인터넷방송통신학회논문지
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• 제22권5호
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• pp.49-54
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• 2022

최근 클라우드 시스템에서 병렬가속기를 사용하는 사례가 늘면서 가속기 내에서 멀티태스킹을 통해 자원 이용률을 높이는 것이 중요한 이슈로 부각되고 있다. 본 논문에서는 병렬가속기 내 자원 사용 패턴을 컴퓨팅 중심과 메모리 중심으로 분류하여 워크로드를 배치하는 방식이 자원 이용률 측면에서 충분한 효과를 나타내지 못함을 보이고, 워크로드별 상세 자원 이용률에 기반한 새로운 스레드 블록 스케줄링 기법을 제안한다. 제안한 기법은 기존 방식과 달리 프로파일링과 스케줄링을 분리하여 스케줄링시의 오버헤드를 줄이고 병목 자원이 일치하지 않는 워크로드들을 최대한 중복 배치하여 자원 이용률을 높인다. 다양한 가상머신 시나리오에 대한 시뮬레이션 실험을 통해 제안한 기법이 병렬가속기의 처리량을 평균 130.6%, 최대 161.4%까지 개선함을 보인다.

• Journal of Yeungnam Medical Science
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• 제40권2호
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• pp.172-178
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• 2023

Background: Laparoscopic cholecystectomy (LC) is a noninvasive surgery, but postoperative pain is a major problem. Studies have indicated that erector spinae plane block (ESPB) has an analgesic effect after LC. We aimed to compare the efficacy of different ESPB anesthetic concentrations in pain control in patients with LC. Methods: This retrospective study included patients aged 20 to 75 years scheduled for LC with the American Society of Anesthesiologists physical status classification I or II. ESPB was administered using 0.375% bupivacaine in group 1 and 0.25% in group 2. Both groups received general anesthesia. Postoperative tramadol consumption and pain scores were compared and intraoperative and postoperative fentanyl requirements in the postanesthesia care unit (PACU) were measured. Results: Eighty-five patients were included in this analysis. Tramadol consumption in the first 12 hours, second 12 hours, and total 24 hours was similar between groups (p>0.05). The differences between postoperative numeric rating scale (NRS) scores at rest did not differ significantly. The postoperative NRS scores upon bodily movement were not statistically different between the two groups, except at 12 hours. The mean intraoperative and postoperative fentanyl requirements in the PACU were similar. The difference in the requirement for rescue analgesics was not statistically significant (p=0.788). Conclusion: Ultrasound-guided ESPB performed with different bupivacaine concentrations was effective in both groups for LC analgesia, with similar opioid consumption. A lower concentration of local anesthetic can be helpful for the safety of regional anesthesia and is recommended for the analgesic effect of ESPB in LC.

• 상하수도학회지
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• 제19권3호
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• pp.288-294
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• 2005

This study was conducted to evaluate the grit removal efficiency of tornado block-type vortex grit separator. Vortex grit separator was manufactured for this study, and it was characterized by the impeller and tornado block installed in separator. Impeller was installed to increase water velocity in the separator and tornado block was installed to increase the grit lifting efficiency. Pilot study was also conducted in A sewage treatment plant (STP) in Gyeonggi province from November 2003 to May 2004 (64 days). Major findings are as follows. 1. Impeller was proven to increase water velocity in the grit separator, especially in low flow rate. This influence will increase separation ratio of organics from grits, preventing those organics from sedimentation. 2. Sand (with 0.2~0.3mm size) removal efficiency was over 98 % and 96 %, at the flow rate of $500m^3/day$ and $750m^3/day$ under the condition that impeller rotation velocity kept at 15 rpm. Originally that grit separator was designed to have the capacity of $500m^3/day$. $750m^3/day$ was tried to investigate the performance of this type of grit separator under overload condition. Stable grit removal was still available to the extent of 150% of designed capacity. 3. It took less than 3 minutes for the grit separator to completely lift out 3 kgs of 0.2-0.3 mm sized, settled sand at the bottom to 2,060 mm high above water surface. But it showed the tendency to spend a little more time on lifting the grit as the grit size and the vertical height of the lift increased. 4. During experimental duration in A STP, it was found that the average amount of inlet grit was about 981 g/day (160~1,685 g/day) under $500m^3/day$ of operation condition, but it varied so severely during the experimental duration. After classification of discharged grit according to its size, grit with 0.3-0.42 mm size was found as largest part of output.