• Smart Structures and Systems
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• v.20 no.6
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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.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.10a
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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.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2004.11a
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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.

• Journal of Physiology & Pathology in Korean Medicine
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• v.28 no.2
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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.

• Journal of the Korean Society of Costume
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• v.52 no.6
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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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• v.42 no.2
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• pp.275-278
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• 2009

Leiomyosarcoma of the inferior vena cava (IVC) is a rare malignant tumor. Yet tumors of a smooth muscle origin are the most common primary neoplasms of the major veins, and the inferior vena cava is the most common site of origin. We report here on a 65-year-old female patient who had been suffering from dyspnea and abdominal discomfort for 3 weeks before admission. The abdominal computed tomography (CT) scan and IVC cavogram showed an IVC mass extending from the right atrium to above the level of the right renal vein, obstructing the IVC, and the radiological findings were suggestive of an IVC leiomyosarcoma. We resected the tumor and reconstructed the IVC with a patch PTFE graft. The follow-up abdominal CT revealed no recurrence and obstruction of the IVC for 6 months after the operation.

• Journal of Veterinary Clinics
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• v.34 no.6
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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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• v.4 no.1
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• pp.104-107
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• 2001

Intussusception is a frequent cause of bowel obstruction in the first five years of life and it is one of the most common surgical emergencies in infancy and early childhood. The age of five months child was administered in Department of Pediatrics of Chunchon Sacred Heart Hospital. His main symptoms were vomiting and high fever for three days. Abdominal sonography, air reduction and abdominal computerized tomography (CT) were performed and the conclusion of these study was intussusception due to cyst mass lesion; duplication cyst, mesenteric cyst or Meckel's diverticulum. He was transferred for operation. We had performed laparotomy for reduction of the intussusception. Operative findings revealed ileocolic type of intussusception due to cystic tumor on ileocecal valve that was invaginated into the cecum, and hyperplasia of the Peyer's patch were seen. But we failed manual reduction because of the tumor in the ileocecal area. So we had performed partial resection of the ileocecum. Diverticulum of the ileum was confirmed by pathologic examination. We experienced unusual cause of the intussusception. So we report this case with a review of the literatures.

• Journal of Microbiology and Biotechnology
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• v.15 no.3
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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.

• Journal of Satellite, Information and Communications
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• v.5 no.2
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• pp.50-56
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• 2010

Most mission trajectory design technologies for space exploration have been utilized the Patched Conic Approximation which is based on Hohmann transfer in two-body problem. The Hohmann transfer trajectory is basically an elliptic trajectory, and Patched Conic Approximation consists of Hohmann transfer trajectories in which each trajectory are patched to the next one. This technology is the most efficient method when considering only one major planet at each patch trajectory design. The disadvantages of the conventional Patched Conic Approach are more fuel (or mass) needed and only conic trajectories are designed. Recent space exploration missions need to satisfy more various scientific or engineering goals, and mission utilizing smaller satellites are needed for cost reduction. The geometrical characteristics of three-body dynamics could change the paradigm of the conventional solar system. In this theoretical concept, one can design a trajectory connecting around the solar system with comparably very small energy. In this paper, the basic three-body dynamics are introduced and a spacecraft mission trajectory is designed utilizing the three-body dynamics.