• Applied Chemistry for Engineering
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• v.27 no.3
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• pp.259-264
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• 2016

In this study, we applied six different norbornene dialkyl esters as a plasticizer to an isoprene rubber (IR) and evaluated replaceability of DEHP which is an endocrine disruptor. IR test sheets were prepared by blending IR, norbornene dialkyl ester, vulcanizing agent, etc. and processing properties of the IR were evaluated by measuring Toque, scorch time, cure time and mooney viscosity. Mechanical properties of IR test sheet including hardness, tensile strength, 100% modulus and elongation were also measured and the physical properties of norbornene dialkyl ester applied as a plasticizer were compared to those using DEHN. Both the maximum and minimum toque for the norbornene dialkyl ester as a plasticizer were similar to those of using DEHP. In addition, the scorch and cure time of the former were slightly longer than those of the latter. The mooney viscosity for the case of DEHN was slightly lower than that of the latter. DEHN was also superior to DEHP in terms of processing. The hardness and thermal properties of all IR test sheets were measured to be similar to each other. The linear alkyl chain of norbornene compounds also exhibited good tensile characteristics.

• Proceedings of the SCSK Conference
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• 2003.09b
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• pp.26-31
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• 2003

Korean Ginseng is a medicinal herb which grows naturally in korea. an ancient country situated in north-eastern Asia. Its medical use was already well known to herb doctors in this region about five thousand years ago since the effectiveness of korean ginseng has been recognized through practical use for a long time. Korean Ginseng has always been regarded as a devine cure. The name "Ginseng" can be found in various medicinal books. many of which were written as early as B.C. 100. In the records of many chinese medical books. dating from the inception of publishing, it was noted that Korean Ginseng was of the highest level of quality. Korean Ginseng originally grew in the mountains of korea. However, this wild Korean Ginseng(js called SANSAM) could not meet the ever-increasing demands. and from the 16th century. it has been cultivated on farms for mass processing and supplying in korea(js called INSAM). It was already recognized in korea a long time ago(B.C. 57 - A.D. 668) that Korean Ginseng possessed the qualities of panacea, tonic and rejuvenator, and had other medicinal properties as well. The effectiveness of Korean Ginseng is widely recognized among south-eastern Asians as well as Chinese. As its effect has been proved scientifically. Korean Ginseng is now becoming the ginseng for all human beings in the world. Korean ginseng is differently called according to processing method. Dried thing is Insam(white ginseng), boiled or steamed is Hongsam(red ginseng). 장뇌삼(long headed ginseng) is artificially grown in the mountain no in field for a long time. So the body is thin and some long. but ingredients are concentrated. Korean wild ginseng(SANSAM) is rare in these days but we developed cosmetic ingredient. The scientific name of Korean Ginseng is Panax Ginseng. It has acknowledge as a natural mysterious cure among the notheastern peoples. because of its broad medicinal application. The origin of the word" Panax" derived from panacea. a Greek word meaning cure-all. According to the classification method of herb medicines in the Chinese medicinal book. "God-Farmer Materia Medica(A.D. 483-496) korean Ginseng was described as the superlative drug: panacea. tonic and rejuvenator. We studied skin immunological effect. collagen synthesis. cell growth and whitening effect of SANSAM extract. IN cosmetics.. SANSAM extract had skin fibroblast cell growth effect. recover damaged skin in the sun and protect fine wrinkle. Also. In hair product.. inhibits hairless, white hair.its hairless, white hair.

• Journal of Technologic Dentistry
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• v.13 no.1
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• pp.27-31
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• 1991

The purpose of this study was to evaluate the effect of curing time and curing temperature on the hear - Curing of acrylic resin using ring furnace. Specimens were fabricated from 2 kinds(Laboron, Bertex) heat-cured resin. Total 200 samples were divided into 4 groups(70$^{\circ}C$, 100$^{\circ}C$, 13$^{\circ}C$, 150$^{\circ}C$) and each group was divided into 5 small groups(30 min., 45min., 60min., 75min., 90min.). A microscope(Olympus Coll Co. Japan) was used to examine a randomly selected central zone, midzone and surface for each complete specimen. The results of the experiment were as follows : 1. To obtain non-polymerzation, cure the resin for 30 minutes at 70$^{\circ}C$ and 100$^{\circ}C$ in a ring furnace. 2. To obtain with porosity, cure the resin for 45 minutes, 60 minutes and 75 mintes at 70$^{\circ}C$ and for 90 minutes at 150$^{\circ}C$ in ring furnace. Porosity appears in Laboron for 30 minutes, 45 minutes at 150$^{\circ}C$ in a ring furnace. 3. Every other specimens connot get a sight of special problem with makes eye in the made surface.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.26 no.8
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• pp.1653-1665
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• 2002

One of the most significant problems in the processing of composite materials is residual stresses. The residual stresses may be high enough to cause cracking in the matrix even before external loads are applied and can degrade the integrity of composite structures. In this study, thermo-viscoelastic residual stresses occurred in the polymeric composite cylinder are investigated. This type of structure is used for the launch vehicle fuselage. The time and degree of cure dependent thermo-viscoelastic constitutive equations are developed and coupled with a thermo-chemical process model. These equations are solved with the finite element method to predict the residual stresses in the composite structures during cure. A launch vehicle experiences high thermal loads during flight and re-entry due to aerodynamic heating or propulsion heat, and the thermal loads may cause thermal buckling on the structure. In this study the thermal buckling analysis of composite cylinders are performed. Two boundary conditions such as all clamped and all simply supported are used for the analysis. The effects of laminates stacking sequences, shapes and residual stresses on the critical buckling temperatures of composite cylinders are investigated. The thermal buckling analysis is performed using ABAQUS.

• Journal of the Korean Applied Science and Technology
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• v.22 no.2
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• pp.116-122
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• 2005

Room temperature cure type of acryl-urethane coatings with high solid content were prepared in this study. Acrylic resins with 80% solid content were cured with hexamethylene diisocyanate (Desmodure N-3600). The cure time of prepared coatings BEHCC-84 (BEHC-84 : $T_g=0^{\circ}C$) and BEHCC-87 (BEHC-87 : $T_g=30^{\circ}C$), measured by rigid-body pendulum method, was recorded 8.3 hours and 3.8 hours, respectively. Dynamic viscoelastic experiment also revealed the glass transition temperature of BEHCC-84 and BEHCC-87 to be $T_g=40.3^{\circ}C$ and $T_g=43.3^{\circ}C$, respectively. It was found that the adhesion and flexural properties among various propeties of coatings were enhanced by the incorporation of caprolactone acrylate monomer into the acrylic resins.

• Journal of Korean Academy of Nursing
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• v.50 no.5
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• pp.699-713
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• 2020

Purpose: The purpose of this study was to understand and describe the experiences of patients with Meniere disease. Methods: Data were collected from February 19, 2019, to February 5, 2020, through individual in-depth interviews with 13 Meniere patients. Verbatim transcripts were analyzed using Colaizzi's phenomenological analysis. Results: The experiences of patients with Meniere disease were clustered into the following four themes from 22 meaning units: 1) Complex unfamiliar symptoms that shatter both balance of the body and peace of the heart; 2) A disease that medical treatment and health professionals cannot cure; 3) Suffering hardships that cannot be understood by non-Meniere sufferers; and 4) Making daily efforts to become healthier. Symptoms of Meniere disease are life-shattering and depressing because they are neither visible nor easily curable. Over time, as they accepted the reality of living with the disease, the participants would shift their focus from complete symptomatic cure to leading a healthy and more balanced life. Conclusion: This study shows that Meniere disease has a pervasive impact on all aspects of the patients' lives. Patients are prone to experiencing restrictions in their social functioning and activities. They also experience psychosocial problems due to the unseen nature of their symptoms. This study elucidates the experiences of Meniere patients and the need for nursing intervention to help improve their quality of life and ability to self-manage. Lastly, this study shows the need for a coordinated interdisciplinary approach to raising public awareness of the disease.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2002.10a
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• pp.261-264
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• 2002

Interfacial evaluation, damage sensing and cure monitoring of single carbon fiber/thermosetting composite with different curing processes was investigated using electro-micromechanical test. After curing, residual stress was monitored by measurement of electrical resistance (ER) and then it was compared to correlate with various curing processes. In thermal curing, curing shrinkage appeared significantly by matrix shrinkage and residual stress due to the difference in thermal expansion coefficient (TEC). The change in electrical resistance (ΔR) on thermal curing was higher than that on ultraviolet (UV) curing. For thermal curing, apparent modulus was the highest and reaching time until same strain was faster. So far thermal curing shows strong durability on the IFSS after boiling test.

• Elastomers and Composites
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• v.29 no.1
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• pp.18-29
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• 1994

The purpose of this study is to investigate reinforced effect between silica treated by coupling agents and rubber matrix under the configuration chemical bonds, and the effect of silica particles coated by organic polymers using aluminum chloride as the catalyst. In vulcanization characteristies were tested by Curastometer. The M-series vulcanizates were reached to the fastest optimum cure $time(t_{90})$ and R-series vulcanizates with the same formula had the shorted optimum cure times. Tensile characteristics measuring with a tensile tester revealed that the M-series vulcanizate was the best in the physical properties, such as tensile strength. In 100% modulus, however, the S-series vulcanizates appeared to be better than the other vulcanizates. Also, hardness showed the following order : S-series>R-series>M-series with the order of elongation R-series>M-series>S-series. In SEM test, shapes of chemical treated silicas were observed. The dispersion of filler in the SBR composite appeard uniformly. In RDS test for the dynamic characteristics, G' indicates that S-3 shows the highest value with the next order M-3>R-3, and the order of damping values are as followe: M-3>M-3>R-3.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.12
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• pp.39-64
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• 1999

Under the CISG, there is a unequitable factor in comparing buyer's remedy with seller's remedy. In my opinion, CISG is more unequitable remedy clause than UCC or UNIDROIT principle of International Commercial Contract(1994) between seller and buyer. First, buyer who accepted defect goods must give seller notice the facts that seller delivered defect goods in two years after accepting defect goods. The cap of two year is unreasonable in a position of aggrieved buyer. This is being provided as 'within reasonable time' in UCC and there is no such provision in UNIDROIT Principle. Second, Buyer can avoid contract when seller breached fundamentally contract or seller didn't set a additional performance period about breaching of contract. Accordingly if buyer would not set a additional performance period, although seller's breachment of contract, he could not avoid the contract. Therefore, From a viewpoint of aggrieved buyer avoidable right of contract is restrainted. Third, to compare seller's remedy with buyer's, seller have more opportunity to cure breachment of contract than buyer. Under the CISG buyer is relatively placed at disadvantage in remedy of aggrieved party. In connection with remedy of aggrieved party, 'UNIDROIT principle of international commercial contracts' instead seller and buyer of aggrieved party, so there is not unequitable factor in remedy of aggrieved parties.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.20 no.8
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• pp.731-735
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• 2007

We developed the 4channel Light Medical Therapy Apparatus for External Injury Cure using a high brightness LED. This equipment was fabricated using a micro-controller and a high brightness LED, and designed to enable us to control light irradiation time, intensity, frequency and so on, Especially, to control the light irradiation frequency, FPGA was used, and to control the change of output value, TLC5941 was used. Control stage is divided into 4 levels by program. Consequently, the current value could be controlled by the change of level in Continue Wave(CW) and the output of a high brightness LED could be controlled stage by stage. Compared with one LED irradiation, several LEDs irradiation could increase optical power.