• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.8 no.2
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• pp.35-43
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• 1999

The paper describes an approach for measuring delivery flow ripple generated by oil hydraulic axial piston pumps. In order to reduce pressure ripple which cause to undesirable noise. vibration and fatigue in hydraulic systems it is indispensible measure a delivery flow ripple from pumps. Since the flow ripple measurement of flow pumps is independent of the dynamic characteristics of the connected hydraulic circuit the measurement of flow ripple is most suitable for pump fluid-borne noise rating. The measurement of flow ripple with high frequencies from axial piston pumps is made by applying the remote instantaneous flow rate measurement method which is based on the dynamic characteristics between pressure and flow rate in hydraulic pipeline. The measured flow ripple waveforms are influenced by the configuration of V-shaped triangular relief groove in the valve plate. It can be seen that the appropriate relief groove in valve plate reduces the pressure and flow ripple amplitude and frequency spectrum for high harmonics.

• The Korean Journal of Pain
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• v.11 no.2
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• pp.314-316
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• 1998

Psoas compartment block has been used to provide anesthesia and analgesia of hip joint. This block is advocated for relief of pain of various origins in the thigh, leg and lumbar area. A-40-year-old women complained of pain in the left thigh and lumbar area after operation of the second lumbar vertebral compression fracture. To relieve pain, caudal block was performed. This block reduced in lumbar pain but left thigh pain persisted. So, we were performed psoas compartment block using mepivacaine and dexamethasone, which relieved the pain in the left thigh and lumbar area. We recommend psoas compartment block as useful and simple method for patients with thigh and lumbar area pain, especially when the epidural block is not feasible.

• The Korean Journal of Pain
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• v.3 no.1
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• pp.21-26
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• 1990

One hundred among 320 patients who underwent splanchnic nerve block were evaluated retrospectively by telephone or letters. After splanchnic nerve block most of the patient experienced relatively good pain relief until death. The results were as follows 1) The duration of pain relief and survival time were well correlated. 2) The duration of survival time after the block was varied from 35 days to 240 days. These data suggest that the splanchnic nerve block is a satisfactory and reliable method for terminal cancer pain and results in a painless life until death.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2003.10b
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• pp.67-72
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• 2003

The cold precision forging of spur gears has been researched, and the effects of relief-hole shape and forging process on the spur gears forming has been analyzed. The results present that the forging load decreases when a suitability diameter of relief-hole is chosen, but the function is not obvious. The spur gears precision forging method with an adjustable movement of concave mould can benefit both the top and the bottom comers forming of the spur gears, full fill the tooth cavity, and decrease the forging load.

• Journal of Power System Engineering
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• v.17 no.1
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• pp.77-84
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• 2013

The proportional pressure control valve that was used to relief valve has different dynamic characteristics on each case. Because this valve has different assembling or processing error and environmental condition. However, a customer who used the relief valve wants to have a steadily performance even if the dynamic characteristics of valve was changed. For this reason, the manufacturer try to make the robust controller that has simple structure. This paper concerns about the design of robust controller that didn't affected by plant parameter's changing. The control strategy is a model reference control that conducted by on line identification problem, gradient method and Lyapunov equation. This adaptvie control law's validity that this paper deal with was confirmed by an results of step response test or hysteresis test.

• Journal of Welding and Joining
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• v.15 no.3
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• pp.29-35
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• 1997

실제로 용접구조물의 재료에는 항상 내부 잔류응력이 존재하며 그 크기는 재료내의 내부 잔류응력간의 평형의 원리(Self-equilibrating system)에 의해 결정 된다. 일반적인 구조 강도설계에서 행해지는 탄성해석에서는 재료 내부에 존재하는 잔류응력을 고려하지 않기 때문에 설계시에 계산된 응력이 심하중하의 구조물에서 발생하는 응력과 같다고 볼 수는 없다. 철강재료를 사용한 구조물의 경우 구조물 제작 공정 전반에 걸친 성형가공 및 조립과정에 수반되어 재료 내에는 잔류응력이 발생되며 특히 용접조립에 의해 용접부 근방에서는 재료의 항복강도 수준의 상당히 큰 용접응력 이 발생하게 된다. 일반적으로 용접잔류응력의 완화법으로 가장 확실한 방법은 후열 처리법(Post weld heat treatment, PWHT)이지만 이 방법의 적용은 구조물의 크기에 제한을 받게 된다. 따라서 PWHT를 적용하기 어려운 구조물에 대해서는 다른 방법에 의해 용접잔류 응력을 완화시켜야 하며 이 경우에 일반적인 방법으로 기계적 응력완화 법(Mechanical stress relief method, MSR)이 있다. 본고에서는 MSR의 기본원리에 대하여 간단하게 정리하고 실 구조물에 대한 MSR 적용시 고려해야 할 제반사항을 위하여 단순 용접부에 대한 MSR 적용 실험결과와 실제 압력용기를 대상으로 MSR을 자체 제작된 기술절차서에 따라서 시행하고 MSR의 적용성에 대해서 검토하였다.

• The Korean Journal of Pain
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• v.8 no.1
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• pp.99-102
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• 1995

Psoas compartment block has been used to provide anesthesia for orthopedic surgical procedures and postoperative pain control. Nowadays this block is advocated for the management of pain in the thighs, legs and lumbar area for various reasons. To relieve pain in the thigh and leg, 21 times of block were performed and observed clinically in the 17 patients at our hospital. The results were excellent for the relief of pain in metastatic cancer patients. And this block is satisfactory in the thigh pain but not in the leg pain. So we recommend psoas compartment block as a useful and simple method for the relief of pain in metastatic cancer pain in the thigh.

• Proceedings of the Korean Institute of Interior Design Conference
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• 2005.05a
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• pp.75-78
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• 2005

In according to the rising rate of divorce, single parent family has increased rapidly. And the number of single mother families is up to 80% of total single parent families. Especially the residential problem of low-income single mother families has been issue in social scope. But now facilities to accept these families are too short in Korea. Therefore this study aims for basic analysis of short-term residential facilities for single mother family. The survey of written documents and investigation of existing facilities are used by the method of study. In addition relief and rehabilitation facilities for mother and child in Seoul is analyzed by domestic example because of similarity to the model of this study.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09a
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• pp.395-396
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• 2006

To manufacture a flange for a compressor with a relief groove by using powder metallurgy in order to prevent deformation to the compressor in operation, powder material for the flange is charged into a mold; an ablative member having a melting point lower than that of the powder material is positioned at a place where a relief groove is to be formed; the flange is formed by compressing the powder material and the ablative member; and the formed flange is sintered at a temperature between the melting point of the powder material and the ablative member so as to melt and remove the ablative member. It made according to the new method has more excellent strength and airtight property than the conventional one. It is analyzed that the ablative member is melted and penetrated into the flange structure during the sintering process, which results in improvement of the airtight property and increase of the strength.

• Proceedings of the SAREK Conference
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• 2004.06a
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• pp.224-224
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• 2004