• 한국정보통신학회논문지
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• 제20권8호
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• pp.1452-1459
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• 2016

압축 센싱은 샤논/나이퀴스트 표본화 정리를 만족하는 나이퀴스트 율 보다 더 적은 수의 표본화 주파수로 신호를 획득하더라도 그 신호가 성긴 신호라는 조건 하에 샘플링을 가능하게 하는 신호 처리 기술이다. 일반적으로 측정 예측방식은 작은 블록 크기에서 성능이 좋은 반면에 복원 이미지 품질은 큰 블록으로 복원하는 것이 좋다. 이러한 두 개의 상충하는 속성을 해결하기 위해 압축 센싱은 작은 블록에서 행해지고, 복원은 큰 블록에서 수행하게 되는 구조화된 측정 행렬을 사용하며, 이러한 방법으로 예측과 복원 모두 동시에 개선을 추구한다. 본 논문에서는 구조화된 측정 행렬을 확장함으로써 블록 크기에 따른 다양한 방식이 비교되어진다. 다양한 실험 결과를 통해 $4{\times}4$ 하다마드 행렬을 이용한 구조화된 측정 행렬이 블록 크기가 4의 크기에서 가장 좋은 성능을 보여주었다.

• The Korean Journal of Pain
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• 제9권1호
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• pp.145-150
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• 1996

The purpose of this study was to evaluate and compare the effectiveness of ilioinguinal-hypogastric nerve blocks(IHNB) and caudal block in producing post-orchiopexy and post-heniorrhaphy analgesia in children. Forty consenting healthy children, ages 3~10yr, were randomly assigned to receive caudal bupitvacaine (0.125%, 0.5ml/kg), or IHNB bupivacaine (0.25%, 0.3 ml/kg). Blocks were performed following the induction of general anesthesia, be fore the operation. Pre-anesthetic medication in form of atropine 0.01 mg/kg, droperidol 0.05 mg/kg were given intramuscularly one hour before induction to 40 children. Children were induced with thiopental sodium 5 mg/kg and succinylcholine 1 mg/kg intravenously. Anesthesia was maintained with oxygen-nitrous oxide ($FiO_2$ 0.3) and ethrane. When the patients stabilized after induction. IHNB was done in the supine position and caudal block was done in the lateral position. The local anaesthetic was injected after negative aspiration. Postoperative pain was assessed with face pain rating scale (RPRS) at rest on discharge of recovery room, and 5 hours after discharge of recovery room, and the "red and white" visual analogue scale (VAS) at rest and mobilization from supine to sitting position on discharge of recovery room, and 5 hours after discharge of recovery room. Post-operative recovery was quiet and comfortable, without side effect. Relief of ain was complete in both IHNB group and caudal group. Surgeons, parents and recovery room personnel were satisfied. There were no surgical or anesthetic complications. In our study, the postpoerative pain scores were similar in both IHNB group and caudal group. IN conclusion, we found that both IHNB and caudal blocks before the start of surgery for orchiopexy & herniorrhaphy are safe and effective in controlling the postoperative pain of children.

• 대한전자공학회논문지SP
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• 제45권5호
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• pp.87-94
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• 2008

본 논문에서는 손실된 블록의 은닉을 위한 방향성을 가지는 블록 복구 방법을 제안한다. 일반적으로 영상의 강한 에지는 웨이블릿 영역에서 큰 계수 값을 가지기 때문에 분산 또한 큰 값으로 나타난다. 손실 블록의 에지 방향을 추정하기 위해서 웨이블릿 계수들의 분산을 이용한 $X^2$ 가설 검증 기법을 적용한단. 추정된 에지의 방향에 따라 보간을 수행하며, 손실 화소를 보간하기 위하여 사용되는 화소는 에지 방향에 따라 결정된다. 제안 방법은 이전 방법과의 성능비교에서 주관적으로나 객관적으로 나 더 좋은 성능을 나타낸다.

• Clinics in Shoulder and Elbow
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• 제25권4호
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• pp.339-346
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• 2022

Rotator cuff tear is the most common cause of shoulder pain in middle-age and older people. Arthroscopic rotator cuff repair (ARCR) is the most common treatment method for rotator cuff tear. Early postoperative pain after ARCR is the primary concern for surgeons and patients and can affect postoperative rehabilitation, satisfaction, recovery, and hospital day. There are numerous methods for controlling postoperative pain including patient-controlled analgesia, opioid, interscalene block, and local anesthesia. Regional blocks including interscalene nerve block, suprascapular nerve block, and axillary nerve block have been successfully and commonly used. There is no difference between interscalene brachial plexus block (ISB) and suprascapular nerve block (SSNB) in pain control and opioid consumption. However, SSNB has fewer complications and can be more easily applied than ISB. Combination of axillary nerve block with SSNB has a stronger analgesic effect than SSNB alone. These regional blocks can be helpful for postoperative pain control within 48 hours after ARCR surgery.

• The Korean Journal of Pain
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• 제10권1호
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• pp.113-116
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• 1997

Sensorineural hearing loss(SNHL) is defined as a sudden hearing impairment which was develope over a period of hours to days. The definitive cause of SNHL is unknown in most cases. Disturbance of the blood flow of the inner ear is a main causal hypotheses. Most symptomatic treatment is focusing to improving the blood flow of the inner ear. At our hospital, most patients are recommended to bed rest, vasodilators(nicotinic acid, antihistamines) and stellate ganglion block(SGB) for two weeks. We experienced two cases of recurrence immediately after recovery from SNHL. They discontinued SGB after initial recovery. due to associated pain with operation and or psychologic stress. One patient resumed SGB and medication treatment, but the second who gave up treatment was not recovered. Therefore, we recommend to continuance of treatment of stellate ganglion blocks to improve recovery rate of SNHL and avoid further trauma and psychologic stress during the recovery period of SNHL.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2003년도 하계종합학술대회 논문집 Ⅳ
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• pp.2351-2354
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• 2003

A new transform coder for arbitrarily shaped image segments is proposed. In the encoder, a block-based DCT is applied to the resulting image block after shifting pixels within the image segment to block border and padding the mean value of the pixels to empty region. For reducing the transmission bit rate, the transform coefficients located in padded region are truncated and only the remaining transform coefficients are transmitted to the decoder. In the decoder, the transform coefficients truncated in the encoder are recovered using received transform coefficients and a block-based inverse DCT is performed.

• Membrane and Water Treatment
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• 제9권2호
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• pp.105-113
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• 2018

Maillard reaction products like melanoidins present in industrial fermentation wastewaters are complex compounds with various functional properties. In this work, novel ultrafiltration (UF) mixed matrix membrane (MMM) composed of polysulfone (PSF) and nanocomposites was prepared through a phase inversion process for the recovery of melanoidins. Nanocomposites were prepared with acid functionalized multiwalled carbon nanotubes (MWCNTs) as the reinforcing filler for chitosan-thermoplastic starch blend. Higher nanocomposites content in the PSF matrix reduced the membrane permeability and melanoidins retention indicating tighter membrane with surface defects. The membrane surface defects could be sealed with dilute polyvinyl alcohol (PVA) solution. The best performing membrane (1% nanocomposites in 18% PSF membrane sealed with 0.25% PVA coating) resulted in uniform melanoidins retention of 98% and permeability of 3.6 L/m2 h bar over a period of 8h. This demonstrates a low fouling PSF membrane for high melanoidins recovery.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2010년도 추계학술대회 초록집
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• pp.129.2-129.2
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• 2010

As a part of the government renewable energy policy, KOWEPO is constructing 300MW IGCC plant in Taean. IGCC plant consists of gasification block, air separation unit and power block, which performance test is separately conducted. Overall performance test for IGCC plant is peformed to comply with ASME PTC 46. Major factors affected on the overall efficiency for IGCC plant are external conditions, each block performance(gasification, ASU, power block), water/steam integration and air integration. Performance parameters of IGCC plant are cold gas efficiency, oxygen consumption, sensible heat recovery of syngas cooler for gasification block and purity of oxygen, flow amount of oxygen and nitrogen, power consumption for air separation unit and steam/water integration among the each block. The gas turbine capacity applied to the IGCC plant is 20 percent higher than NGCC gas turbine due to the low caloric heating value of syngas, therefor it is possible to utilize air integration between gas turbine and air separation unit to improve overall efficiency of the IGCC plant and there is a little impact on the ambient condition. It is very important to optimize the air integration design with consideration to the optimized integration ratio and the reliable operation. Optimized steam/water integration between power block and gasification block can improve overall efficiency of IGCC plant where the optimized heat recovery from gasification block should be considered. Finally, It is possibile to achieve the target efficiency above 42 percent(HHV, Net) for 300MW Taean IGCC plant by optimized design and integration.

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 2003년도 봄 학술발표회 논문집
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• pp.329-330
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• 2003

In general, the thermoplastic elastomers have the elastic recovery property caused by phyical crosslinks after the stress is applied. Segmented block copolyetheresters also have been used as elastomers. Many$\^$l-2/ tried to improve the elastic recovery of those which are less elastic than polyurethane. We confirmed that the copolyetherester based on poly(2,6-butylene naphthalate)(PBN) ha.4 segment had the high melting temperature, whcih was useable at the broader temperature range and the one based on poly(1,3-trimethylene terephthalate)(PTT) the high crystallinity, which would be expected to get the high elastic recovery. (omitted)

• 한국정보과학회논문지:소프트웨어및응용
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• 제29권11호
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• pp.767-774
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• 2002

기존의 원영상 복원 기술은 주로 신호 처리 분야에서 영상의 형성(formation), 저장 및 통신상에서 발생되는 왜곡 현상을 복원하는 연구가 많이 이루어 졌다. 원 영상 복원과 관련된 기존의 연구는 블록 정합(block matching algorithm)을 이용한 원영상 복원 방법이 있다. 이 방법은 오 정합(incorrect matching)이 발생하기 쉽고, 오 정합 시 에러가 전파되는 문제점이 있다. 그리고 장면 전환이 2회 이상 발생될 경우 장면 전환 지점과 지점 사이의 복원이 불가능하다는 문제점이 있다. 본 논문에서는 기존의 문제점들을 해결하기 위하여 확장적 블록 정합 방법(EBMA: Extended Block Matching Algorithm)과 영역 보상법(Region compensation method)을 이용한 원영상 복원 방법을 제안하고자 한다. 원영상 복원에 사용하기 위하여 비디오 사전 정보(장면 전환 정보, 카메라 모션 정보, 캡션 영역 정보)를 추출한다. 추출된 캡션 영역 정보를 이용하여 캡션 문자의 구성 요소 정보를 추출한다. 추출된 비디오 사전 정보를 이용하여 복원의 방향성을 결정하고, 복원의 방향성에 따라 문자의 구성 요소 단위로 확장적 블록 정합 방법과 영역 보상법을 이용하여 원영상 복원을 수행한다. 실험결과 확장적 블록 정합 방법은 빠른 물체의 움직임이나 복잡한 배경에 영향을 받지 않고 복원이 잘 되는 것을 알 수 있었다. 참조할 원영상이 없이 원영상 복원을 수행하는 영역 보상법의 복원 결과 또한 좋음을 볼 수 있었다.