• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2004.04a
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• pp.404-409
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• 2004

To maximize the productivity in machining molds and dies, machine tools should operate at high speeds. During the high speed operation of moving frames or spindles, vibration problems are apt to occur if the machine tool structures are made of conventional steel materials with inferior damping characteristics. However, self-excited vibration or chatter is bound to occur during high speed machining when cutting speed exceeds the stability limit of machine tool. Chatter is undesirable because of its adverse effect on surface finish, machining accuracy, and tool life. Furthermore, chatter is a major cause of reducing production rate because, if no remedy can be found, metal removal rates have to be lowered until vibration-free performances is obtained. Also, the resonant vibration of machine tools frequently occurs when operating frequency approaches one of their natural frequencies because machine tools have several natural frequencies due to their many continuous structural elements. However, these vibration problems are closely related to damping characteristics of machine tool structures. The polymer concrete has high potential for machine tool bed due to its good damping characteristics with moderate stiffness. This paper presents the use of polymer concrete and sandwich structures to overcome vibration problems. Also, co-cure bonding method for functional part mounting was exhibited experimentally, by which manufacturing time and cost for polymer concrete bed will be remarkably reduced.

• Textile Coloration and Finishing
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• v.32 no.2
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• pp.96-102
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• 2020

Recently, it was reported that chitosan or APTMS(3-aminopropyltrimethoxysila ne) treatment to cotton using the simple pad-dry-cure method has potential to prepare textile materials for military chemical warfare protective clothing. However, it is not confirmed which method is more efficient. Therefore, this study aims to quantitatively compare detoxification properties of chitosan treated cotton fabric with those of APTMS treated cotton fabric. Detoxification properties were evaluated using the well-known organic phosphorous nerve agent stimulant, diisopropylfluorophosphate(DF P). With the same amount of chitosan and APTMS on the surface of the cotton fabrics, APTMS treated cotton fabric exhibited 10% higher detoxification properties than chitosan treated cotton fabric based on the rate of DFP hydrolysis and half-live of DFP calculated from the DFP decontamination ratios of the treated cotton fabrics through time. Therefore, APTMS treatment can be more efficient method to prepare the textile materials for military protective clothing than chitosan treatment.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.1181-1185
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• 2005

Microstereolithography has evolved from the stereolithography technique, and is also based on a light-induced layer-stacking manufacturing. Integral microstereolithography is proposed for building a 3D microstructure rapidly, which allows the manufacture of a complete layer by one irradiation only. In this study, we developed the integral microstereolithography apparatus based on the use of $DMD^{TM}$ as dynamic pattern generator. It is composed of Xenon-Mercury lamp, optical devices, pattern generator, precision stage, controllers and the control program. Also, we estimated curing characteristics in photopolymer. The relationship between the viscosity of diluent-oligomer solutions and curing width, irradiation time and curing property has been studied.

• Journal of Oriental Neuropsychiatry
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• v.5 no.1
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• pp.69-79
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• 1994

In order to prove the effectiveness for anticonvulsion and analgesic of Ukgansan, Ukgansan added Jinphi Banha and Ukgansan added Chunma by experiment, experimental animals(mouse) are injected with strychnine, picrotoxin and caffeine to cause convulsion and ovserved the consumed time from convulsion to death. Comparing data with control group and observation data for frequency of writhing syndrome caused by acetic acid and phenylquinone show the results as follows : 1. Anticonvulsion effect on the convulsion induced by strychnine it was significantly effective in all sample groups. 2. Anticonvulsion effect on the convulsion induced by picrotoxin it was significantly effective in sample A and B. 3. Anticonvulsion effect on the convulsion induced by caffeine it was not recognized in all sample groups. 4. Analgesic effect on the pain induced by acetic acid it was significantly effect in sample A and C. 5. Analgesic effect on the pain induced by phenylquinone it was significantly effective in sample A and C. The results show that Ukgansan can be an effectual cure on anticonvulsion and analgrsic, Ukgansan added Jinphi·Banha on anticonvulsion, and Ukgansan added Chunma on analgesic.

• The Journal of Internal Korean Medicine
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• v.22 no.4
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• pp.519-525
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• 2001

Objectives : In order to study the effect of oriental medical therapy on chronic prostatitis patient, the change of WBC counts on expressed prostatic secretion(EPS) was investigated. Methods : Chronic prostatitis patient who had been diagnosed by EPS test was re-tested as same way after improvement of symptom And then we investigated the change of WBC counts on EPS according to therapeutic period, age, usual habit, herb medicine and symptom of each patient, and his and his sexual partner's past history of STD or UTI. Results : According to the change of WBC counts on EPS, improvement rate was 83.3%, cure rate was 46.7%. The youth who didn't have the usual habit of enduring ejaculation during sexual intercourse, enduring urination and sitting long time a day was improved well. Conclusions : According to the above results, it is suggested that oriental medical therapy is effective to the change of WBC counts on EPS.

• Journal of Chest Surgery
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• v.12 no.4
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• pp.424-428
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• 1979

Clinical observation were performed on 25 cases of Mediastinal tumors or Cyst, those were admitted and treated at the Department of Thoracic and Cardiovascular Surgery, Korea University Hospital, during the 6 years period from March 1973 to March 1979. The following results are obtained. Of 25 cases, 19 patients were males and 6 patients were females. Range of age varied widely from 2 years to 72 years. Approximately 28% were younger than 15 years of age at the time of diagnosis. The common subjective symptoms of the patients were anterior chest pain [36%], coughing [27%], dyspnea and a few incidence of hemoptysis. Diagnostic procedures were posteroanterior and lateral chest roentgenorgrams, Chest tomograms, Brochograms, Esophagograms, Mediastinoscopy, Scalene and Axillary Lymph node biopsy, and Needle aspiration biopsy. In the histological distribution on Mediastinal tumors in order of frequency, Neurogenic tumor 6 cases [25%], Lymphoma 5 cases [21%], Bronchogenic cyst 4 cases [17%], Pericardial cyst 2 cases [8.3%], Teratodermoid tumor 2 cases [8.3%], and each one case of Rhabdomyosarcoma, Seminoma, Cavernous hemangioma, Anthracosis, Tuberculoma were noted respectively. Of 24 cases of the histologically confirmed Mediastinal tumors, 6 cases [24%] were malignant. Thoracotomy for removal of tumor or cyst was performed on 17 cases and offered cure of all benign tumors. In 6 cases of malignant tumors, Chemotherapy with Vincristine, Cyclophosphamide and Prednisolone was given to 1 case Lymphoma. There was no case of postoperative mortality.

• Journal of Pharmaceutical Investigation
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• v.36 no.2
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• pp.83-87
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• 2006

Poly(acrylic acid) (PAA) was identified to possess good mucoadhesive properties ensuring its application to extend the retention times of the formulations at the oral cavity, intended route of administration using the polymer. In the noncross-linked state, PAA will swell and become eroded owing to the presence of salivary flow from the site of application. The formation of cross-links between the polymer chains will allow swelling but prevents the erosion of the dosage form. In the current study, cross-linking was achieved by esterification of the PAA chains with sucrose. The density of crosslinking was modified by changing sucrose concentration and the duration of cure time. The cross-linking density of the polymer hydrogel was assessed by equilibrium swelling studies. The mucoadhesion testing method allowed a comparative study of the hydrogels prepared. An inverse relationship between equilibrium swelling and peak detachment force showed that increased PAA chain density per unit area enhanced the mucoadhesive interaction.

• Polymer(Korea)
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• v.24 no.2
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• pp.220-227
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• 2000

Silica and carbon black filled natural rubber (NR) vulcanizates were prepared with different mixing modes and amounts of fillers. Curing characteristics, morphology. and tear properties of the NR vulcanizates were investigated. The NR vulcanizates filled with silica and carbon black sequentially showed longer induction time ($t_2$), cure index ($t_{90}$ ), and lower maximum torque ($T_{max}$ ) than the NR vulcanizates filled with them simultaneously, during curing process. The former showed superior dispersion of fillers and tear properties to the latter. The NR vulcanizates containing 30 phr of silica showed excellent properties in the experimental range.

• Journal of Institute of Control, Robotics and Systems
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• v.19 no.4
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• pp.322-327
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• 2013

Recently many people have been troubled with perennial allergic rhinitis. But there is no way to cure for root of it until now. Therefore many medical treatments to release symptoms of perennial allergic rhinitis have been researched. One of them is localized aerosol hyperthermia, which injects $42^{\circ}C{\sim}43^{\circ}C$ vapor into nasal cavity. Vapor inhalator for localized aerosol hyperthermia has been researched in foreign country. But on the other hand it has rarely been researched inside of the country. Since most clinics and hospitals have used imported vapor inhalator, it is needed to develop domestic vapor inhalator. In the paper, a superior vapor inhalator compared to former developed one is developed. The superiority of it comes from direct-vapor heating instead of water heating to control vapor temperature. The developed vapor inhalator has shorter rising time than the existing one because of direct-vapor heating. Furthermore vapor generation part and control part of the vapor inhalator developed as one piece mock-up. It enables the vapor inhalator to have smaller size. Many laboratory tests are performed and compared to existing results to prove its performance.

• Physical Therapy Korea
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• v.22 no.3
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• pp.98-105
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• 2015

Muscular dystrophy is a hereditary musculoskeletal disorder caused by a mutation in the dystrophin gene. Duchenne muscular dystrophy (DMD) is one of the most common, and progresses relatively faster than other muscular dystrophies. It is characterized by progressive myofiber degeneration, muscle weakness and ultimately ambulatory loss. Since it is an X-linked recessive inheritance, DMD is mostly expressed in males and rarely expressed or less severe in females. The most effective measurement tool for DMD is magnetic resonance imaging (MRI), which allows non-invasive examination of longitudinal measurement. It can detect progressive decline of skeletal muscle size by measuring a maximal cross-sectional area of skeletal muscle. Additionally, other techniques in MRI, like $T_2$-weighted imaging, assess muscle damage, including inflammation, by detecting changes in $T_2$ relaxation time. Current MRI techniques even allow quantification of metabolic differences between affected and non-affected muscles in DMD. There is no current cure, but physical therapist can improve their quality of life by maintaining muscle strength and function, especially if treatment (and other forms of medical intervention) begins in the early stages of the disease.