• 대한기계학회논문집
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• 제1권2호
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• pp.65-72
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• 1977

Major problems in the design and use of refief valve are (a) chattering because of instability, (b) excessive pressure differential which makes the valves crack far below maximum pressure diminishing useful flow in the system. In this study, A magnet-coupled relief valve is investigated theoretically and experimentally in order to improve the performance of a conventional direct type reliefvalve. A theory is developed to predict the performance, response, and stability of the magnet-coupled valve taking into account the delivery line response. In the experiment, a typical magnet-coupled relief valve is designed on the basis of the analytical results; the discharge rates are measured varying the supply pressure, and both the pressure-time curves and valve displacament-time curves are recorded providing the supply pressures greater than the setting pressure. The measured override characteristic curves are then compared with those of conventional pilot type and direct type releif valves. It is showm that the excessive pressure differential of a magnet-coupled relief valve becomes less than that of a conventional direct type valve. It is also shown that the most important chatacteristic of a magnet-coupled relief valve is to eliminate valve chattering due to instability regardless of the magnitude of setting pressures and discharge rates, which suggests wide applications of the idea of the use of a magnet in the design of hydraulic valves.

• 한국콘텐츠학회논문지
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• 제13권1호
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• pp.199-209
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• 2013

이 연구는 법사회학적 체제 모형을 이론적 근거로 하여, 교원소청심사에 영향을 미치는 내 외적 환경의 변화를 확인하고, 그 결과로서 나타나는 소청사건수와 인용율의 시계열(정권단위별) 경향을 파악하고자 하였다. 환경요인으로서 외부의 사회적 영향 요인과 내부적 교육정책 요인의 특성은 평등성에서 효율성으로 변화되고 있고, 1991년부터 2011년까지 21년간 소청심사 사건수와 인용율 추이는 1990년대의 경우 낮은 폭의 증감을 보이다가 2000년대 들어 노무현 정부 출범 이후 사건 수는 급증하고 인용율은 급격히 감소하는 경향을 보이고 것으로 확인되었다. 민주화 등에 따른 교원의 권익보호 기대의 증가, 정치철학의 차이에 따른 교원의 역할 갈등이 표출되면서 정부와 교원 사이의 분쟁을 소청을 통해 해결하려는 경향이 증가하면서 소청제기 건수를 증대시켰고, 한편으로 교원에 대한 책무성 제고를 강조하는 교원정책, 학부모 단체 등 시민단체의 성장에 따른 교원에 대한 보다 엄격한 평가기준의 적용 요구가 인용율 하락에 직간접적으로 영향을 미친 것으로 짐작된다. 이러한 연구결과를 바탕으로 향후 교원소청심사제도 운영의 법적 안정성 보장을 위한 제도 개선의 필요성을 제언하였다.

• Asian Pacific Journal of Cancer Prevention
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• 제15권20호
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• pp.8797-8800
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• 2014

Objective: To analyze cost-effectiveness of morphine, MS contin and oxycodone in the treatment of cancer pain, providing guidance for rational drug use in the clinic. Methods: Confirmed by histology, a total of 171 patients with various cancers who required analgesic treatment were selected and divided into 3 groups, 57 cases for each group, given morphine, MS contin and oxycodone, respectively. If there appeared a poor short-term effect or aggravated sudden pain during the treatment, a short-acting morphine injection was given and adverse reactions were processed by symptomatic treatment. The pain relief rate and adverse reactions of groups were observed and pharmacoeconomics evaluation was undertaken. Results: The pain relief rates with morphine, MS contin and oxycodone were 89.5%(51/57), 91.2%(52/57) and 93.0%(53/57), respectively, with no difference samong groups (${\chi}^2=4.4489$, P=0.6162). The occurrence rates of adverse reactions were 59.7%(34/57), 54.4%(31/57) and 43.9%(25/57), again with no significant variation (P>0.05). The ratios of cost-effectiveness (C/E) for the 3 groups were $14.6{\pm}7.21$, $15.0{\pm}7.44$ and $16.1{\pm}8.10$. When the price of 3 kinds of analgesics was reduced by 10%, the ratios of cost-effectiveness were $12.2{\pm}6.53$, ($13.4{\pm}6.08$ and $14.5{\pm}6.74$ but there was no differences when compared with before the price adjustment (t=1.86, P=0.0651; t=1.30, P=0.1948; t=1.17, P=0.2453). Conclusion: Morphine, MS contin and oxycodone give similar pain relief and adverse reaction rates but of all, morphine is the preferred drug for the treatment of cancer pain from the perspective of pharmacoeconomics.

• Radiation Oncology Journal
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• 제35권1호
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• pp.71-77
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• 2017

Purpose: Although the technical developments of radiotherapy have been remarkable, there are currently few reports on the treatment results of radiotherapy for local recurrence of rectal cancer treated with surgery alone as initial treatment in this three-dimensional conformal radiotherapy era. Thus, we retrospectively evaluated the treatment results of radiotherapy for local recurrence of rectal cancer treated with surgery alone as the initial treatment. Materials and Methods: Thirty-two patients who underwent radiotherapy were enrolled in this study. The dose per fraction was 2.0-3.5 Gy. Because the treatment schedule was variable, the biological effective dose (BED) was calculated. Results: Local control (LC) and overall survival (OS) rates from the completion of radiotherapy were calculated. The 1-, 2-, 3-, 4-, and 5-year LC rates were 51.5%, 24.5%, 19.6%, 19.6%, and 13.1%, respectively. LC rates were significantly higher for the high BED group (${\geq}75Gy_{10}$) than for the lower BED group (<$75Gy_{10}$). All patients who reported pain achieved pain relief. The duration of pain relief was significantly higher for the high BED group than for the lower BED group. The 1-, 2-, 3-, 4-, and 5-year OS rates were 82.6%, 56.5%, 45.2%, 38.7%, and 23.2%, respectively. There was a trend toward higher OS rates in with higher BED group compared to lower BED group. Conclusion: For patients with unresectable locally recurrent rectal cancer treated with surgery alone, radiotherapy is effective treatment. The prescribed BED should be more than $75Gy_{10}$, if the dose to the organ at risk is within acceptable levels.

• Journal of Korean Neurosurgical Society
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• 제48권3호
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• pp.240-243
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• 2010

Objective : Radiofrequency (RF) medial branch neurotomy is an effective management of lumbar facet syndrome. However, pain may recur after period of time. When pain recurs, it can be repeated, but the successful outcome and duration of relief from repeated procedures are not clearly known. The objective of this study was to determine the success rate and duration of pain relief from repeated radiofrequency medial branch neurotomy for lumbar facet syndrome. Methods : A retrospective review of medical records was done on 60 consecutive patients, from March of 2006 to February of 2009, who had an initial successful RF neurotomy but subsequently underwent repeated procedures due to recurrence of pain. All procedures were done in carefully selected patients after at least two responsive medial branch nerve blocks. C-arm fluoroscopic guide, impedance, sensory and motor threshold monitoring tools were used for the precise placement of electrodes. Responses of repeated procedures were compared with initial radiofrequency neurotomy for success rates and duration of pain relief. Results : There were 48 females and 12 males. Mean age was 52.4 years (range, 26-83). RF medial branch neurotomy was done on one side in 38 and both sides in 22 patients, each covering at least three segments. Average visual analog scale at last procedure was 6.8. Twelve patients had previous lumbar operations, including 4 patients with instrumentations. Fifty-five patients had two procedures and five patients had three procedures. Mean duration of successful pain relief (> 50% of previous pain for at least 3 months period) after initial radiofrequency neurotomy was 10.9 months (range, 3-28) in 51 (85%) patients. From repeated procedures, successful pain relief was seen in 50 (91%) patients with average duration of 10.2 months (range, 3-24). Five patients had third procedure, which was successful in 4 (80%) patients with mean duration of 9.8 months (range, 5-16). This was not statistically different from initial results. There were no permanent neurological complications from the procedures. Conclusion : Results of this study indicate that the frequency of success and durations of relief from repeated RF medial branch neurotomy for lumbar facet syndrome are similar to initial results that provided relatively prolonged period of pain relief without major side effects Each procedure seems to provide successful pain relief for about 10 months in more than 85% of carefully selected patients when properly done.

• Asian Pacific Journal of Cancer Prevention
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• 제15권16호
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• pp.6823-6827
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• 2014

Objective: This study was conducted to investigate the efficacy of pancreatic drainage for pain relief in advanced pancreatic cancer. Method: Seventy-one patients with pancreatic carcinoma were divided into two groups: dilated and non-dilated pancreatic ducts. All patients underwent endoscopic retrograde cholangiopancreatography (ERCP), endoscopic biliary stenting and pancreatic stenting. Visual Analog Scale (VAS) scores, pain remission rates and survival time were evaluated during follow-up. Results: The post-ERCP VAS score of the dilated group was lower than that of the non-dilated group at 1 and 3 months post-ERCP. There was no difference at 6 months. The pain remission rate in the dilated duct group was significantly higher than that in non-dilated duct group in 1 and 3 months post-ERCP. The median survival times were 8.17 and 8.22 months respectively. Conclusion: Endoscopic pancreatic drainage can relieve pain of advanced pancreatic cancer accompanied by safe dilation of the pancreatic duct.

• 한국안전학회지
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• 제35권6호
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• pp.32-45
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• 2020

The problem of determining the discharge rates of gases from pressurized vessels through pressure relief devices was dealt with comprehensively. First, starting from basic fluid flow equations, detailed modeling procedures were presented for isentropic nozzle flows and frictional flows in a pipe, respectively. Meanwhile, physical explanations were given to choking phenomena in terms of the acoustic velocity, elucidating the widespread use of Mach numbers in gas flow models. Frictional flows in a pipe were classified into adiabatic, isothermal, and general flows according to the heat transfer situation around the pipe, but the adiabatic flow model was recommended suitable for gas discharge through pressure relief devices. Next, for the isentropic nozzle flow followed by adiabatic frictional flow in the pipe, two equations were established for two unknowns that consist of the Mach numbers at the inlet and outlet of the pipe, respectively. The relationship among the ratio of downstream reservoir pressure to upstream pressure, mass flux, and total frictional loss coefficient was shown in various forms of MATLAB 2-D plot, 3-D surface plot and contour plot. Then, the profiles of gas properties and velocity in the pipe section were traced. A method to quantify the relationship among the pressure head, velocity head, and total friction loss was presented, and was used in inferring that the rapid increase in gas velocity in the region approaching the choked flow at the pipe outlet is attributed to the conversion of internal energy to kinetic energy. Finally, the Levenspiel chart reproduced in this work was compared with the Lapple chart used in API 521 Standatd.

• 한국안전학회지
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• 제14권3호
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• pp.168-173
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• 1999

The purpose of this study is to analyze death injuries and operation troubles of urban transit. No difference was shown in death rates between Line 1 of Pusan urban transit and Line 5, 7, And 8 of Seoul metropolitan transit. And relief time by another train did not depend upon the number of crews. We concluded that thorough inspection and preventive maintenance of trains and facilities are necessary for safe and timely service of urban transit.

• Journal of Chest Surgery
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• 제32권10호
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• pp.935-938
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• 1999

Effusive-constrictive pericarditis is a very rare disease in infants but has high motality rates when not treated. There were some reports of pericardial constriction associated with intrapericardial abscess that led to pericardiectomy. The patient was admitted due to fever, cyanosis, and abdominal distension. We treated the patient with antibiotics and pericardiostomy but the symtoms did not improved, therefore, pericardiectomy was perfomed immediately. The patient with effusive-constrictive pericarditis was immediately relief on the symptoms and the treatment was successful.

• 근관절건강학회지
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• 제1권1호
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• pp.48-70
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• 1994

The purpose of this study was to determine the effects of music therapy on acute, subacute and chronic pain and depression of musculoskeletal trauma patients. The study was designed using nonequivalent control group pretest-posttest design within the framework of an adaptation model. The subjects were composed of forty patients, and twenty of them were assigned to the experimental group and twenty to the control group within the unit of patients. Data were summarized as follows : 1. There were significant changes of pain scores in an experimental and a control group measured before and after the treatment. 2. There were significant changes of pulse rates, respiration rates and systolic blood pressure, but were no significant changes of diastolic blood pressure in an experimental and a control group measured before and after the treatment. 3. There were no significant changes of the amount of ${\beta}$-endorphin in an experimental and a control group measured before and after the treatment. 4. There were no significant changes of depression scores in an experimental and a control group measured before and after the treatment. As a result, music therapy was a useful nursing intervention for relief of acute, subacute and chronic pain. Two suggestions could be made on the ground of the results of this study. 1. On the basis of endogenous pain control theory, it's necessary to research the changes of the amount of ${\beta}$-endorphin as the effect of the music therapy on patients having severe pain. 2. It's necessary to research the changes of the amount of ${\beta}$-endorphin according to the lapse of time after the music therapy for pain relief.