• 제목/요약/키워드: Block Effect

검색결과 2,008건 처리시간 0.025초

진단용 방사성동위원소 취급 시 L-block 차폐기구 사용에 따른 핵의학 종사자의 장기 선량평가 (Organ Dose Assessment of Nuclear Medicine Practitioners Using L-Block Shielding Device for Handling Diagnostic Radioisotopes)

  • 강세식;조용인;김정훈
    • 대한방사선기술학회지:방사선기술과학
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    • 제40권1호
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    • pp.49-55
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    • 2017
  • 의료기관 내 핵의학 종사자는 방사성동위원소 취급 시 사용하는 선원의 종류, 방사능량, 차폐기구의 사용 여부에 따라 종사자 개인별로 광범위한 피폭선량을 나타낼 수 있다. 이에 본 연구에서는 몬테카를로 기법을 기반으로 한 모의실험을 통해 진단용 방사선원 취급 시 종사자의 장기별 선량평가와 L-block 차폐기구 사용에 따른 선량감소효과를 분석하였다. 그 결과, 방사선원의 취급 위치에 근접할수록 높은 장기선량 분포를 나타내었고, ICRP 조직가중치에 따라 유효선량 분포가 상이한 양상을 보였다. 또한 L-block 두께에 따른 선량감소효과는 차폐두께 증가에 따라 지수함수 분포로 감소되는 경향을 나타내었으며, 방사선원별 선량감소효과는 방출하는 감마선 에너지에 비례하여 낮은 차폐효과를 보였다.

차량용 냉각 팬과 엔진 블럭의 간격 변화에 따른 성능 특성 연구 (Experimental Study on Performance Characteristics with Various Spacings between Automobile Cooling Fan and Engine Block)

  • 유병민;유기완;장재경;이강덕;홍성규
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2009년도 추계학술대회 논문집
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    • pp.143-149
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    • 2009
  • Recently, according to the tendency to the more comfortable automobile, the improvement of performance of the cooling fan is required. The performance of cooling fan is affected by many peripheral parts, such as radiator, condenser, engine block and etc. Therefore, it is important to consider the effect of peripheral components on the fan performance in design and analysis stages. In this paper, the performance of automobile cooling fan is investigated experimentally by using the large capacity fan tester based on the ASHRAE and the AMCA standards. In particular, the various spacing between cooling fan and engine block are considered to obtain the effect of engine block. An empirical relation between the fan flow rate and the spacing was proposed.

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경부에서의 신경차단시 발생한 경련과 의식소실 및 호흡정지 -증례 보고- (Convulsion, Loss of Consciousness and Respiratory Arrest during Nerve Block at Neck -Two case reports-)

  • 최승택
    • The Korean Journal of Pain
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    • 제11권2호
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    • pp.343-345
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    • 1998
  • Stellate ganglion block and cervical epidural nerve block are frequently practiced in pain clinics because of simple procedure and good effect. Nerve block at head and neck may produce serious complication such as loss of consciousness and cardiac arrest. Blood supply is rich in neck and inadvertent arterial injection of local anesthetics may enter directly into brain. We experienced convulsion and respiratory arrest during SGB and cervical epidural block. The patients were resuscitated successfully and recovered without any adverse effects.

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Block Error Performance Analysis of Mobile Multimedia Communication System in Nakagami fading Channel

  • 강희조;손성찬
    • 디지털콘텐츠학회 논문지
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    • 제5권2호
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    • pp.101-105
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    • 2004
  • The block error probabilities of noncoherent frequency shift keying in a Nakagami fading channel are presented in this papaer. The channel fading speed, show or fast. is consider in evaluating block error probabilities. The effectiveness of diversity combing and error correction coding in improving block error performance is examined. The effect of cochannel interference on block error performance is also studied in this paper.

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개흉술 후 흉부동통억제를 위한 늑간신경냉동 요법과 약물주입요법에 관한 비교연구 (Cryoanalgesia vs Bupivacain Intercostal Nerve Block for the Post -thoracotomy Pain)

  • 최영호
    • Journal of Chest Surgery
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    • 제27권11호
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    • pp.942-947
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    • 1994
  • Post-thoracotomy pain is so severe that lead to postoperative pulmonary complications due to the patient`s inability to cough, deep breathing and chest wall motion. Many authors have been trying to reduce the post-thoracotomy pain, but there is no method of complete satisfaction. In 1990, we reported the result that the cryoanalgesia reduce the immediate postoperative pain significantly. We try to compare the effect of cyroanalgesia with the effect of Bupivacain intercostal nerve block for the post-thoracotomy pain control. Ninety patients, who undergoing thoracotomy in Korea University Medical Center Guro Hospital between the January 1993 and September 1993, were evaluated. The patients were divided into three groups : Group A, control, the patients without pain control procedure [N=30], Group B, the patients with Bupivacain intercostal nerve block [N=30], Group C, the patients with cryoanalgesia [N=30]. Postoperative analgesic effects were evaluated by the scoring system which made arbiturary by author. The results were that the Bupivacain intercostal nerve block markedly reduced the immediate postoperative pain compare with two other groups, the cryoanalgesia reduced the immediate postoperative pain significantly compare with control group, the pain reduction effect of the two groups- cryoanalgesia and Bupivacain intercostal nerve block- were not different at postoperative seventh day, probably due to the action time of Bupivacain and the result that there were no significant complications of the procedures.

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3 ${\times}$ 3 라틴방격모형의 검정력 분석 (Power analysis for 3 ${\times}$ 3 Latin square design)

  • 최영훈
    • Journal of the Korean Data and Information Science Society
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    • 제20권2호
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    • pp.401-410
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    • 2009
  • 두 블럭인자와 하나의 주인자로 구성된 3 ${\times}$ 3 라틴방격모형의 특성으로 인하여 주효과를 검정하기 위한 순위변환 통계량의 검정력은 모집단의 분포유형에 상관없이 모수적 통계량의 검정력보다 전반적으로 월등히 높은 수준이다. 특히 세인자가 모두 고정인 경우, 하나의 블럭인자만이 랜덤인 경우, 두 블럭인자가 모두 랜덤인 경우의 순서로 주효과를 검정하기 위한 순위변환 통계량의 검정력이 모수적 통계량의 검정력에 비하여 상대적으로 높다. 또한 검정하고자 하는 주효과의 크기가 크되 동시에 동일크기의 하나의 블럭효과 및 또다른 블럭효과 크기는 상대적으로 작을수록 주효과를 검정하기 위한 순위변환 통계량의 검정력은 모수적 통계량의 검정력보다 상대적 우위성을 갖는다.

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4 × 4 그레코라틴방격모형의 검정력 연구 (Power study for 4 × 4 graeco-latin square design)

  • 최영훈
    • Journal of the Korean Data and Information Science Society
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    • 제23권4호
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    • pp.683-691
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    • 2012
  • $4{\times}4$ 그레코라틴방격모형은 모집단의 분포에 상관없이 주효과 검정을 위한 순위변환 통계량의 검정력이 모수적 통계량의 검정력보다 전체적으로 높은 우위성을 갖는다. 효과크기가 균등간격이 아닌 경우에 주효과 검정을 위한 순위변환 통계량의 검정력은 효과크기가 균등간격인 경우보다 다소 낮지만 모수적 통계량의 검정력에 비하여 월등한 비교우위를 갖는다. 순위변환 통계량의 검정력은 블럭효과의 수가 줄어들거나 효과크기가 작아질수록 모수적 통계량의 검정력보다 월등히 우세함을 보인다. 블럭효과들이 존재할 때는 주효과에 비하여 블럭효과들이 모두 작거나 하나의 블럭효과에 편중된 경우에 순위변화 통계량의 검정력이 모수적 통계량의 검정력보다 더욱 우수하다. 이는 상호작용없이 다인자인 네 개의 주인자 및 블럭인자만으로 구성된 그레코라틴방격모형의 특성에 의한 결과로, 앞으로 구체화하지 못한 다인자로 구성된 요인실험계획모형 등에 확대 적용할 순위변환기법의 가능성을 제시한다.

Regional nerve blocks for relieving postoperative pain in arthroscopic rotator cuff repair

  • Tae-Yeong Kim;Jung-Taek Hwang
    • 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.

Effect of MBCP block as carrier of rhBMP-2 in combination with ePTFE membrane on bone formation in rat calvarial defects

  • Shin, Chul-Woo;Cho, Kyoo-Sung;Jung, Sung-Won;Kim, Chang-Sung;Choi, Seong-Ho;Yun, Jeong-Ho
    • Journal of Periodontal and Implant Science
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    • 제38권sup2호
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    • pp.325-334
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    • 2008
  • Purpose: The carrier used as delivery agent for bone morphogenetic proteins(BMPs) should also act as a scaffold for new bone formation. Moreover, bone formation should be predictable in terms of the volume and shape. This study examined the osteogenic effect of macroporous biphasic calcium phosphate (MBCP) block combined with ePTFE membrane as a carrier for recombinant human bone morphogenetic proteins (rhBMP-2). In addition, the additive effect of ePTFE membrane on bone formation was evaluated. Materials and Methods: Eight-millimeter critical sized calvarial defects were created surgically in 28 male Sprague-Dawley rats. The animals were divided into 2 groups containing 14 animals each. The defects were treated with either rhBMP-2/MBCP block (rhBMP-2/MBCP group) or rhBMP-2/MBCP block/ePTFE membrane (rhBMP-2/MBCP/ePTFE group). A disc-shaped MBCP block (3 mm height and 8 mm diameter) was used as the carrier for the rhBMP-2 and ePTFE membrane was used to cover the rhBMP-2/MBCP block. The histologic and histometric parameters were used to evaluate the defects after 2- or 8-week healing period (7 animals/group/healing interval). Results: The level of bone formation in the defects of both groups was significantly higher at 8 weeks than that at 2 weeks (P < 0.05). The ePTFE membrane has no additional effect compared with the rhBMP-2/MBCP block only. However, at 8 weeks, rhBMP-2/MBCP/ePTFE group showed more even bone formation on the top of the MBCP block than the rhBMP-2/MBCP group. Conclusion: These results suggest that the ePTFE membrane has no additive effect on bone formation when a MBCP block is used as a carrier for rhBMP-2.

알코올을 이용한 흉부교감신경절차단술에 대한 임상경험 및 합병증 -증례 보고- (The Clinical Experiences and Complications of Percutaneous Neurolysis of Upper Thoracic Sympathetic Ganglion by Using Ethylalcohol -A report of three cases-)

  • 권옥희;김종일;반종석;민병우
    • The Korean Journal of Pain
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    • 제8권2호
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    • pp.374-377
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    • 1995
  • Percutaneous neurolysis of upper thoracic sympathetic ganglion was performed by simultaneously injecting 3 ml of pure alcohol into the $T_2$ and $T_3$ levels after testng with same amount of local anesthetics on the same sites. We experienced poor sympatholytic effect or intercostal neuritis and Horner's Syndrome as the result of complication of thoracic sympathetic ganglion block. In Case 1, in spite of the good testing result, neurolytic block effect was poor. In Case 2, intercostal neuritis occurred, but neuralgia subsided within 3 weeks. In Case 3, Horner's Syndrome occurred for 1 day. To increase the success rate of block and decrease the incidence of complications, good radio-opaque dye appearance and good test block effect should be obtained.

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