• Title/Summary/Keyword: Block Effect

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

  • Kang, Se-Sik;Cho, Yong-In;Kim, Jung-Hoon
    • Journal of radiological science and technology
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    • v.40 no.1
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    • pp.49-55
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    • 2017
  • In the case of nuclear medicine practitioners in medical institutions, a wide range of exposure dose to individual workers can be found, depending on the type of source, the amount of radioactivity, and the use of shielding devices in handling radioactive isotopes. In this regard, this study evaluated the organ dose on practitioners as well as the dose reduction effect of the L-block shielding device in handling the diagnostic radiation source through the simulation based on the Monte Carlo method. As a result, the distribution of organ dose was found to be higher as the position of the radiation source was closer to the handling position of a practitioner, and the effective dose distribution was different according to the ICRP tissue weight. Furthermore, the dose reduction effect according to the L-block thickness tended to decrease, which showed the exponential distribution, as the shielding thickness increased. The dose reduction effect according to each radiation source showed a low shielding effect in proportion to the emitted gamma ray energy level.

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

  • Yu, Byoung-Min;Ryu, Ki-Wahn;Jang, Jea-Kyung;Ih, Kang-Duck;Hong, Sung-Kyu
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2009.10a
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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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Convulsion, Loss of Consciousness and Respiratory Arrest during Nerve Block at Neck -Two case reports- (경부에서의 신경차단시 발생한 경련과 의식소실 및 호흡정지 -증례 보고-)

  • Choi, Seung-Tack
    • The Korean Journal of Pain
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    • v.11 no.2
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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

  • Kang Heau-Jo;Son Sung-Chan
    • Journal of Digital Contents Society
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    • v.5 no.2
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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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Cryoanalgesia vs Bupivacain Intercostal Nerve Block for the Post -thoracotomy Pain (개흉술 후 흉부동통억제를 위한 늑간신경냉동 요법과 약물주입요법에 관한 비교연구)

  • 최영호
    • Journal of Chest Surgery
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    • v.27 no.11
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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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Power analysis for 3 ${\times}$ 3 Latin square design (3 ${\times}$ 3 라틴방격모형의 검정력 분석)

  • Choi, Young-Hun
    • Journal of the Korean Data and Information Science Society
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    • v.20 no.2
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    • pp.401-410
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    • 2009
  • Due to the characteristics of 3 ${\times}$ 3 Latin square design which is composed of two block effects and one main effect, powers of rank transformed statistic for testing the main effect are very superior to powers of parametric statistic without regard to the type of population distributions. By order of when all three effects are fixed, when on one block effect is random, when two block effects are random, the rank transform statistic for testing the main effect shows relatively high powers as compared with the parametric statistic. Further when the size of main effect is big with one equivalent size of block effect and the other small size of block effect, powers of rank transformed statistic for testing the main effect demonstrate excellent advantage to powers of parametric statistic.

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

  • Choi, Young-Hun
    • Journal of the Korean Data and Information Science Society
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    • v.23 no.4
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    • pp.683-691
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    • 2012
  • In $4{\times}4$ graeco-latin square design, powers of rank transformed statistic for testing the main effect are superior to powers of parametric statistic without regard to the effect structure with equally or unequally spaced effect levels as well as the type of population distributions such as exponential, double exponential, normal and uniform distribution. As numbers of block effect or effect sizes are decreased, powers of rank transformed statistic are much higher than powers of parametric statistic. In case that block effects are smaller than a main effect or one block effect is higher than other block effects, powers of rank transformed statistic are much higher than powers of parametric statistic in $4{\times}4$ graeco-latin square design with three block effects and one main effect.

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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    • v.25 no.4
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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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    • v.38 no.sup2
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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.

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

  • Kwon, Ok-Hee;Kim, Jong-Il;Ban, Jong-Seock;Min, Byung-Woo
    • The Korean Journal of Pain
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    • v.8 no.2
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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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