• Journal of the Korea Fashion and Costume Design Association
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• v.9 no.3
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• pp.47-57
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• 2007

This study focused on the properties natural dyeing and natural material and on the development of functional material for well-being in apparel industry. Comus officinalis Siebold et Zuccarini is used as natural dyeing material which had been reported that have curable effect for unbalanced immunity, geriatric diseases like urinary tract system, diabetes, hypertension, arthritis, tinnitus, hyperhidrosis and women's diseases like hypermenorrhea. And this material also has anti-cancer effect so that can restraint cancer cells. 3 kinds tester of cotton, wool and silk are dyed by boiled with each dye (flower, fruits, bark of tree) as first dyeing and dried in the shade. These testers are done by post-mordanting method. Aluminium Potassium(Alk(SO4)2), Cuprie Sulfate($CuSO4{\cdot}5H2O$), Stannous Chloride($SnCl2{\cdot}2H2O$), Ferrous Sulfate($FeCl2{\cdot}4H2O$), Titanium Sulfate 24% aqueous solution(Ti(SO4)2) are used as mordants. Dyeing results of Comus officinalis Siebold et Zuccarini flower and bark are shown as yellow color series. And dyeing result of fruits is pink color series. Silk shows the best dyeing property. As the point of view for dyeing property, Ti, Sn, Fe would be the properchoice for mordant. Following results are extracted in this study. Yellow color is resulted in dyeing with Cornus officinalis flower as non-mordanting condition. Yellowish red color is come from dyeing with Comus officinalis fruit as non-mordanting condition. Grayish yellow tone is resulted in dyeing with bark as non-mordanting condition. Orange tone color with Ti-mordanting, green tone color with Sn-mordanting and gray tone color with Fe-mordanting is resulted respectively. However light-fastness of Comus officinalis(flower, fruit, bark) is very low as 1 or 2 level in non-mordanting condition, Comus officinalis flower dyeing is turned out 3 or 4 level and fruit dyeing is 4 or 5 level, bark dyeing is 2 or 3 level with Ti-mordanting respectively. Eventually Comus officinalis fruit has the best light-colorfastness property among all of dyes. dry cleaning colorfastness of Cornus officinalis(flower, fruit, bark) is good as 4 or 5 level in Ti-mordanting condition, perspiration-colorfastness of Cornus officinalis(flower, fruit, bark) is good as 4 or 5 level in Ti-mordanting condition, With these results, this study could conclude that dye-ability, colorfastness problem is getting better after mordanting process and practical usage would be possible.

• Journal of the Microelectronics and Packaging Society
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• v.24 no.2
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• pp.29-35
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• 2017

In this paper, we investigated a manufacturing process of metal micro-wire interconnection on submillimeter diameter catheter. Over the years, flexible electronic researches have focused on flexible plane polymer substrate and micro electrode manufacturing on its surface. However, a curved polymer substrate, such as catheter, is very important for medical application. Among many catheters, importance of submillimeter diameter steerable catheter is increasing to resolve the several limitations of neurosurgery. Steering actuators have been researched for realizing the steerable catheter, but there is no research about practical wiring for driving these actuators. Therefore we developed a new manufacturing process for metal micro-wire interconnection on submillimeter diameter catheter. We designed custom jigs for alignment of the metal micro-wires on the submillimeter diameter catheter. An UV curing system and commercial products were used to reduce the manufacturing time and cost; Au micro-wire, UV curable epoxy, UV lamp, and submillimeter diameter catheter. The assembled catheter was characterized by using an optical microscope, a resistance meter, and a universal testing machine.

• Polymer(Korea)
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• v.24 no.3
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• pp.389-398
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• 2000

Transparent, abrasion resistant coatings with 4~13 ${\mu}{\textrm}{m}$ thickness were prepared by spin-coating on polycarbonates with organic/inorganic hybrid solutions, followed by UV curing and heat treatment at 12$0^{\circ}C$ for 12 hours. The coating solutions were composed of inorganic phase and organic phase in 0:100, 20:80, 30:70, 50:50, 80:20 wt% ratios, respectively, mixed with photoinitiator, senaitizer and surfactant. The inorganic phase was formed by sol-gel reaction of TEOS and silane coupling agent MPTMS in 1 : 2 or 2 : 1 molar ratios, the organic phase consisted of difunctional urethane acrylate oligomeric resin, multifunctional acrylate TMPTA and HDDA in 4 : 3 : 3 wt% ratio. The coating systems were investigated by FT-IR, $^{29}$ Si-NMR spectra. In addition, TGA/DSC for thermal analysis and SEM, AFM observation for coated surface were examined. Gererally, the homogeneity of phases, the surface smoothness of coating and abrasion resistance were improved with the higher content of inorganic component. Namely, coating system with below 10 $\AA$ surface roughness and T$_{g}$ of 15$0^{\circ}C$ showed only 10% decrease in light transmittance after abrasion test, whereas uncoated polycarbonate substrate exhibited 46% decrease..

• Applied Chemistry for Engineering
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• v.27 no.2
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• pp.221-226
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• 2016

Production of eco-friendly and biologically harmless materials is strongly required in all industries. In particular, reducing volatile organic compounds in coating processes is extremely important to secure worker's safety. During recent two decades, extensive research works on water-borne polyurethane dispersion (PUD) have been continuously developed as an alternative to solvent-borne polyurethane. However, PUD was shown inferior mechanical properties to the organic solvent-borne polyurethane due to a limit to the molecular weight increase, which resulted in the limit of applications. To overcome this drawback, several approaches have been examined such as polymer blends and thermal/radiation induced crosslinking. Among these methods, the radiation curing system was suitable for industrialization because of the high crosslinking density and fast curing speed. In this study, we overcame the drawback for PUD via introducing benzophenone radiation curable units to PUD. We synthesized PUD films which possessed good dispersion in water for 30 days, increased Tg and Td more than $5^{\circ}C$ after UV curing film as well as improved young's modulus more than double.

• Journal of Adhesion and Interface
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• v.12 no.3
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• pp.81-87
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• 2011

In this study, UV curing and crosslinking process was introduced for synthesis of acrylic foam tape that can be applied to the the automotive assembly process. Polymerized adhesive are laminated to baseform and varying the thickness of specimens were prepared. To measure basic mechanical properties, stainless steel was used. And in the test peel, dynamic shear and t-block were used. The acrylform adhesive show better results compare with typical adhesive and the properties depand on external factors - thick, wetting time -. To analysis functions of acrylic foam adhesive used to automobile production, evaluate the adhesive properties on the various plastic substrate. In PP and PE are categorized low surface energy materials, their properties have not been expressed. But dynamic shear tests show that some properties could be expressed by the difference break mechanism.

• Journal of Adhesion and Interface
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• v.15 no.1
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• pp.22-30
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• 2014

Self-photoinitiating acrylate (SPIA) which can undergo self-initiation under UV irradiation was synthesized by a Michael addition in the presence of a base catalyst. The SPIA polymerizations were investigated by photo-differential scanning calorimeter (photo-DSC) and surface physical properties such as pendulum hardness and pencil hardness. The results showed that the SPIA can cure upon UV irradiation by itself without a photoinitiator. But we found out that both the curing rate and the conversion were too low for the self-curing reaction of SPIA. In order to improve the SPIA curing properties, we introduced the SPIA/cationic hybrid system and observed the effects of the addition of commercial free radical type monomer and photoinitiator on the curing behaviors. SPIA/cationic hybrid system was the best suitable to improve the SPIA curing properties. The kinetic analysis indicated that the cationic monomer and photoinitiator apparently accelerated the cure reaction and rate of the hybrid SPIA system, mostly due to the synergistic effect of cationic monomer and photoinitiator increasing the mobility of active species and the generation of reactive species (free radical, cation) during the photopolymerization process. The physical properties showed that, unlike typical free radical system, the hybrid systems did not show oxygen inhibition effect because of cationic reaction on the coating surface.

• Korean Journal of Bronchoesophagology
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• v.3 no.1
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• pp.94-100
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• 1997

Background and Objectives : In children with tracheal stenosis, operative management remains a challenging problem due to difficulties of operative techniques and postoperative care. The purpose of this study was to determine the effectiveness of tracheal resection with end to end anastomosis as operative management for tracheal stenosis in children. Materials and Methods : 6 children with severe tracheal stenosis underwent tracheal resection with end to end anastomosis. Causes of stenosis were trauma in 1 case and prolonged intubation or tracheotomy in 5 cases. The diagnoses were made by radiologic evaluation (plain X-ray, CT, 3-Dimensional CT) and confirmed by direct laryngoscopy and ventilating bronchoscopy under general anesthesia. Thyroplasty and unilateral arytenoidectomy were performed in 1 case. Suprahyoid release was done in 1 case with severe adhesion. Decanulation was achieved following postoperative endoscopic examination and pulmonary function test. Postoperative physical and radiologic examinations were given at regular intervals. Results : Stenosis were improved from grade III grade I in 4 cases and from grade II to grade I in 2 cases. Decanulation was achieved on average postoperative 6 months in 5 cases, and 10 years in 1 case due to exertional dyspnea. There were 1 each case of immediate postoperative subcutaneous emphysema, pneumothorax and wound infection. Postoperative granulomas at anastomosis site were treated with laser vaporization under suspension laryngoscope and bronchoscope in 3 cases. There was 1 each case of delayed postoperative vocal cord palsy, aspiration pneumonia and loss of cough reflex. Conclusion In tracheal stenosis of children, tracheal resection with end to end anastomosis has good result with preservation of normal airway. Preoperative evaluation of local factors such as swallowing, vocal cord movement and cough reflex and general condition was important for successful treatment. As the cases in adults, authors considered this operation to be a curable operative management for tracheal stenosis.

• Journal of Life Science
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• v.30 no.12
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• pp.1118-1127
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• 2020

Alzheimer's disease causes progressive neuronal loss that leads to cognitive disturbances. It is not currently curable, and there is no way to stop its progression. However, since medical treatment for Alzheimer's disease is most effective in the early stages, early detection can provide the best chance for symptom management. Biomarkers for the diagnosis of Alzheimer's disease include amyloid β (Aβ) deposition, pathologic tau, and neurodegeneration. Aβ deposition and phosphorylated tau can be detected by cerebrospinal fluid (CSF) analysis or positron emission tomography (PET). However, CSF sampling is quite invasive, and PET analysis needs specialized and expensive equipment. During the last decades, blood-based biomarker analysis has been studied to develop fast and minimally invasive biomarker analysis method. And one of the remarkable findings is the involvement of platelets as a primary source of Aβ in plasma. Aβ can be transported across the blood - brain barrier, creating an equilibrium of Aβ levels between the brain and blood under normal condition. Interestingly, a number of clinical studies have unequivocally demonstrated that plasma Aβ42/Aβ40 ratios are reduced in mild cognitive impairment and Alzheimer's disease. Together, these recent findings may lead to the development of a fast and minimally invasive early diagnostic approach to Alzheimer's disease. In this review, we summarize recent advances in the biomarkers of Alzheimer's disease, especially the involvement of platelets as a source of peripheral Aβ production and its potential as a blood-based biomarker.

• Journal of Hospice and Palliative Care
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• v.6 no.2
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• pp.172-176
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• 2003

Purpose : This study was designed to evaluate the perception of cancer in the students of Korea University. Methods : 1,000 students of Korea University were surveyed by questionnaire from March 2001 to September 2002. Nine hundred ninety two complete questionnaires were returned. The data were analyzed by descriptive statistics, and Chi-square analysis using the SPSS program. Results : 701 students (76.1%) replied that cancer is a curable disease. However, the degree of satisfaction for cancer treatment with modem clinical medicine was low (37.5%). Moreover, they thought that there was no difference between the efficacy of treatment by chemotherapy, alternative medicine, or dietary modification. But, the positive evaluation for the effectiveness of chemotherapy in the students who had cancer patients in their families was higher than that in the students without the experience of cancer patients in their families. Six hundred ninety four students (75.3%) replied positively for euthanasia in terminal cancer patients. And they thought that the dignity and the right of the patients were the most important point that should be considered in making the decision of euthanasia. Conclusions : The credibility to modem clinical medicine for cancer treatment was relatively low in the students of Korea University who had no cancer patients in their families. So, further studies and trials will be warranted to evaluate the causes of these results and improve the credibility of modem clinical medicine for cancer treatment in the general population.

• Journal of Korean Neurosurgical Society
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• v.29 no.11
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• pp.1437-1444
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• 2000

Objectives : Traditionally intracranial meningiomas are regarded as benign and curable tumors. About half of all intracranial meningiomas locate in the skull base region. However, surgical removal of these tumors may be challenging and require special considerations. Here general aspects of skull base meningiomas including clinical presentation, surgical approaches, complications and their recurrence rate are discussed based on our experiences. Methods : A retrospective analysis of 61 consecutive patients with skull base meningioma among 210 patients of meningioma between 1989 and 1998 were done. Results : There were 41 women and 20 men ranging from 13 to 74 years(mean 52 years). These tumors were divided into seven categories according to location : olfactory groove(n＝9), sphenoid ridge(n＝16), cavernous sinus(n ＝2), tuberculum sellae(n＝8), tentorium(n＝13), cerebellopontine angle(n＝12), and foramen magnum meningiomas (n＝1). Surgical approaches were selected on the basis of the tumor attachment, size and extension on preoperative radiologic findings. Total removal(Simpson grade I and II) was achieved in 50 cases(82%), and subtotal removal (Simpson grade III) in 11 patients(18%). According to WHO classification, there were 52 of cases of benign meningioma( 86%), 6 atypical cases(10%), and 3 malignant cases(5%). The most common postoperative complications were CSF leakage(23.0%) and cranial nerve injury(8.2%). Three patient died related with tumor(one was due to surgical complication and the other two due to recurrence) but three patients died from other systemic causes. Mean follow-up period was 51.7 months after surgery. Recurrence occurred in six patients(10.9%) ; three with tentorial meningioma, two with sphenoid ridge, and one in cerebellopontine angle. Conclusion : With advances in neuroradiology and microsurgical techniques, the surgical outcome of miningiomas has been markedly improved with acceptable morbidity and mortality rates. Overall, our surgical results of skull base meningiomas is comparable to other reports. Therefore, with the appropriate operative strategy and techniques, these tumors can be completely removed and good surgical results can be expected.