• Smart Structures and Systems
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• 제20권6호
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• pp.657-668
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• 2017

In this research, an active vibration suppression of a smart beam having piezoelectric sensor and actuators is investigated by designing separate controllers comprising a linear quadratic regulator and a neural network. Firstly, design of a smart beam which consists of a cantilever aluminum beam with surface bonded piezoelectric patches and a designed mechanism having a micro servomotor with a mass attached arm for obtaining variations in the frequency response function are presented. Secondly, the frequency response functions of the smart beam are investigated experimentally by using different piezoelectric patch combinations and the analytical models of the smart beam around its first resonance frequency region for various servomotor arm angle configurations are obtained. Then, a linear quadratic regulator controller is designed and used to simulate the suppression of free and forced vibrations which are performed both in time and frequency domain. In parallel to simulations, experiments are conducted to observe the closed loop behavior of the smart beam and the results are compared as well. Finally, active vibration suppression of the smart beam is investigated by using a linear controller with a neural network based adaptive element which is designed for the purpose of overcoming the undesired consequences due to variations in the real system.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 추계학술대회 논문집
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• pp.918-921
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• 2005

According to the mechanical-electrical coupling characteristics and the electrical Impedance property of resistor-inductor-capacitor(RLC) series resonant circuit, the mechanical impedance analysis of a bimorph piezoceramic patch shunted with a series RLC resonant circuit is conducted. The displacement transfer function of a cantilever beam bonded with a piezoelectric shunt damping module is deduced in the case of single mode vibration of the beam. By the use of vibration damping theory of tuned mass damper system, the parameter optimization of piezoelectric shunt damping system is performed. The optimal resonant state of the shunting circuit can be obtained when the resister and conductor are optimally adjusted. Test results show that the vibration control effect as well improved with optimized piezoelectric shunt system.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2004년도 추계학술대회논문집
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• pp.349-353
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• 2004

A study on optimal placement of constrained layer damping treatment for vibration control of automotive panels is presented. The effectiveness of damping treatment depends upon design parameters such as choice of damping materials, locations and size of the treatment. This paper proposes a CAE (Computer Aided Engineering) methodology based on finite element analysis to optimize damping treatment. From the equivalent modeling technique, it is found that the best damping performance occurs as the viscoelstic patch is placed by means of the modal strain energy method of bare structural panels to identify flexible regions, which in turn facilitates optimizations of damping treatment with respect to location and size. Different configurations of partially applied damping layer treatment have been analyzed for their effectiveness in realizing maximum system damping with minimum mass of the applied damping material. Moreover, simulated frequency response function of the automotive roof with and without damping treatments are compared, which show the benefits of applying damping treatment. Finally, the optimized damping treatment configuration is validated by comparing the locations and the size of the treatment with that of an experimental modal test conducted on roof compartment.

• 동의생리병리학회지
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• 제28권2호
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• pp.238-242
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• 2014

Here we described 2 cancer patients treated by acupuncture for abdominal pain as a complication of bowel obstruction. The patient 1, 43-year-old man was treated with surgery, radiotherapy and chemotherapy for rectal cancer. Two years after surgery, he complained of acute abdominal pain due to small bowel adhesion band. Bowel obstruction and symptoms were not improved by conservative therapy like as fasting, keeping Levin tube, and fluid therapy. 4 months later, he could eat a little rice water, but ileus and abdominal pain persisted despite of applying opiod drug and patch. Got started on acupuncture, electroacupuncture(ST-36) and moxa treatment, pain was relived gradually. He could stop opioids 1 month later and ileus was improved after acupuncture therapy for 2 months. The patient 2, 65-year-old woman got hepatectomy, cholecystectomy, and chemotherapy with cholangiocarcinoma. 6 months after surgery, she got laparotomy again for biopsy of new mass around ascending colon. She started eating after gas passing, but felt abdominal distension. Diffuse paralytic ileus was diagnosed by abdominal X-ray, and she got started conservative therapy. During ST-36 electroacupuncture therapy, symptoms like abdominal pain and distension were improved and could stop opiod patch. But eating aggravated ileus again and clinical finding of mechanical bowel obstruction was appeared. Based on these cases, acupuncture and moxa therapy could be helpful for improving abdominal pain and ileus, but possibility of malignant bowel obstruction should be considered especially in cancer patients.

• 복식
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• 제52권6호
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• pp.165-179
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• 2002

This paper begins with the thesis that the so-called 'Be Slow' Movement has not only affected the contemporary life style but also the current fashion trend in the West as well as in Korea. The influence of the 'Be Slow' Movement on the everyday life of Western and Korean society can be documented by recent books, news reports, and many articles from various kinds of mass media and fashion magazines since the year 2000. The results of this study can be summarized as follows. First. the 'Be Slow' Movement is a new cultural phenomenon and very different from that of the past century. It has emerged very recently and it could affect the life style o( its followers for a long period of time. Second, the influence of 'Be Slow' Movement on everyday life can be witnessed in many behavioral choices. such as the preference of organic food and natural cooking for food and the preference of rural life and a green patch of land for housing. Some aspects of the way of rearing the children and long-term planning of one's life are also under the influence of 'Be Slow' Movement. In a way. the life style Proposed by the 'Be Slow' Movement is somewhat similar to that of 'Bobos'. Third, the influence of 'Be Slow' Movement on the current fashion trend can be observed in the appreciation of time-consuming labour and increased usage of D.I.Y. clothing. The higher value of fashion goods with handcrafted part or scarce luxury item are good examples of the influence by the 'Be Slow' Movement. One can say that the 'Be Slow' Movement is not retrogression, but a re-creation of time and space to be grateful for one's life. Thus, it is not anti-technology but a commercialism with technology in order to enhance the quality of life and to place people in the center of production and consumption. Consequently, one may say that the 'Be Slow' Movement is a appropriate and affluent way of living.

• Journal of Chest Surgery
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• 제42권2호
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• pp.275-278
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• 2009

하대정맥에 생기는 평활근육종은 매우 드문 악성종양이다. 평활근육에서 기원하는 종양은 대정맥의 가장 흔한 원발성 종양이며, 하대정맥이 가장 흔히 발생하는 곳이다. 환자는 65세의 여자 환자로 입원 3주전부터 시작된 호흡곤란과 복부 불쾌감을 호소하여 내원 하였다. 복부 전산화 단층촬영과 하대정맥 조영술에서 우심방에서 우측 신정맥 위까지 확장된 하대정맥 종양이 보였으며, 또한 하대정맥을 폐쇄시키고 있었다. 하대정맥의 평활근육종으로 진단 후 수술은 종양을 제거하고, 하대정맥을 인조혈관 패치를 이용하여 재건하였다. 수술 후 6개월 간의 추적 관찰 중에 실시한 복부 전산화 단층촬영에서 재발과 하대정맥의 폐쇄소견은 없었다.

• 한국임상수의학회지
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• 제34권6호
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• pp.441-444
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• 2017

A 15-year-old spayed female Miniature Schnauzer was presented for unilateral foreleg lameness and pain. On physical examination, left elbow joint swelling and stiffness were identified. On a computed tomography (CT) scan, a periosteal reaction of the left humerus from the distal metaphysis to the epiphysis and cortical destruction of the medial condyle was observed. Based on blood tests, histopathology, and immunohistochemistry, it was concluded as a skeletal histiocytic sarcoma. Since the patient's pain was not controlled despite application of a fentanyl patch, a left forelimb amputation was decided upon as part of the palliative therapy. Metronomic chemotherapy with toceranib phosphate and pamidronate was initiated. Toceranib was administered for 3 months without the development of any adverse effects except mild neutropenia. However, 3 months after initiating treatment, the toceranib was discontinued due to moderate gastrointestinal disturbances. Over the next 2 months, a left mandibular bone mass and cortical bone destruction in the bilateral tibia and tarsal joint were identified on CT. The patient became unwilling to eat and was noted to have severe skeletal pain. The anorexia and lethargy were progressively worsening and the owner decided to euthanize the patient. A necropsy was performed and the patient was definitively diagnosed with disseminated histiocytic sarcoma based on histopathologic and immunohistochemical analyses. This report describes a Miniature Schnauzer dog with DHS managed with surgical removal and metronomic chemotherapy with toceranib that survived with an improved quality of life for 7 months.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• 제4권1호
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• pp.104-107
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• 2001

저자들은 5개월 된 남아에게 장중첩증 원인으로 흔하지 않은 게실로 판명되었던 1례를 치험하여 문헌 고찰과 함께 보고하는 바이다.

• Journal of Microbiology and Biotechnology
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• 제15권3호
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• pp.652-655
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• 2005

This paper describes the development of an enzymatic assay system for the identification of inhibitors of isocitrate lyase (ICL), one of the key enzymes of the glyoxylate cycle that is considered as a new target for antifungal drugs. A 1.6 kb DNA fragment encoding the isocitrate lyase from Candida albicans ATCC10231 was amplified by PCR, cloned into a vector providing His-Patch-thioredoxin-tag at the N-terminus, expressed in Escherichia coli, and purified by metal chelate affinity chromatography. The molecular mass of the purified ICL was approximately 62 kDa, as determined by SDS-PAGE, and the enzyme activity was directly proportional to incubation time and enzyme concentration. The effects of itaconate-related compounds on ICL activity were also investigated. Among them, itaconic acid, 3-nitropropionate, and oxalate had strong inhibitory activities with $IC_{50}$ values of 5.8, 5.4 and $8.6\;{mu}g/ml$, respectively. These inhibitors also exhibited antifungal activity on YPD agar media containing acetate as a sole carbon source, albeit at high concentration. The results indicate that the C. albicans ICL may be a regulatory enzyme playing a crucial role in fungal growth and is a prime target for antifungal agents.

• 한국위성정보통신학회논문지
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• 제5권2호
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• pp.50-56
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• 2010

이제까지 수행된 우주 탐사 임무에서 임무 궤도의 설계는 행성 혹은 위성과 인공위성의 2체 문제 (two-body problem)에 기초한 Hohmann transfer를 기반으로 하는 Patched Conic Approximation 방식이 주로 사용되어져 왔다. Hohmann transfer는 원 궤도에서 다른 원 궤도로 천이할 수 있는 타원 천이 궤도의 설계 방식으로서, Patched Conic Approximation은 태양계를 여러 개의 2체 문제로 분해하고 각기 분해된 2체 시스템 사이의 Hohmann 천이 궤도를 설계하여 조합함으로써 행성 간의 임무 궤도를 설계하는 방식이다. 이 방식은 하나의 행성만을 고려했을 때, 즉 행성과 인공위성의 2체 문제일 때, 가장 효율적인 천이 방식으로 알려져 있고 현재까지의 우주 탐사 임무 설계에 주로 이용되고 있다. 하지만, 우주 탐사 임무가 점차 다양화되고 소형 위성을 이용한 임무 수행의 필요성이 증가함에 따라 기존의 Patched Conic Approximation은 요구되는 연료의 양이 크다는 점과 원뿔꼴(conic) 특성을 가지는 궤도만을 표현할 수 있다는 점에서 한계점을 보이기 시작하고 있다. 이에 반해 3체 동역학의 기하학적 특성은 기존의 태양계의 패러다임을 획기적으로 변화시킨다. 개념적으로는 요구되는 에너지가 매우 적은 에너지로 태양계를 모두 연결하는 궤도를 구성할 수 있기 때문이다. 본 논문에서는2체문제 기반의 임무 궤도 설계 기술의 한계성에서 벗어나 유연하고 효율적인 탐사 임무를 설계한다.