• Elastomers and Composites
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• v.6 no.2
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• pp.47-63
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• 1971

We have studied the blending effects of Diene 33R and styrenebutadiene rubber at various blending ratios of 100/0, 70/30, 50/50, 30/70, 0/100, and of carbon black HAF and ISAF at various compounding ratios of 55 PHR, 65 PHR, 75 PHR for tyre tread rubber. As the results, it was found that ; 1. For tyre tread rubber, when the blending ratio, Diene NF 35R/SBR 1778, indicated 30/70, the physical properties we examined were most excellent. 2. Excellent result was obtained in case of carbon black compounding ratio of 65 PHR. The compounding of ISAF made better result than that of HAF for abrasion quantity, tearing strength, and tensile strength. 3. Heat buildup obtained from compounding carbon black HAF indicated low temperature than that from compounding carbon black ISAF. As the compounding amount of carbon black increased, the heat buildup improved. And as the blending amount of Diene NF 35R decreased, the heat buildup dropped. 4. Carbon black was more efficient to SBR than to Diene Rubber. 5. It is a shortage that elongation revealed low price.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.35 no.5
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• pp.494-498
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• 2022

In this study, SiO₂ 20 phr, ATH 70 phr, and platinum flame retardant were mixed with raw silicone rubber and -10 kV was applied to measure electrostatic charge attenuation voltage, surface resistance, and volume resistance, and the following conclusions were obtained. When the platinum flame retardant was 0 phr, the humidity 74.6% and the temperature was 21.8℃, the potential was half-reduced to 0.63 kV, 0.57 kV, and 0.44 kV when the applied voltage was changed from -10 kV to -8 kV, and the time halved to 50% was increased to 2.40 seconds, 2.47 seconds, and 2.61 seconds. It was confirmed that as the platinum flame retardant increased from 0.1 to 0.3 phr, the potential half-reduced to 0.67 kV, 0.60 kV, and 0.595 kV decreased, and the charge potential attenuation time half-reduced to 50% decreased to 3.44 seconds, 1.78 seconds, and 1.60 seconds. It was confirmed that the surface resistance increased as the humidity decreased, and the volume resistance decreased as the platinum flame retardant increased.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.15 no.12
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• pp.4400-4419
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• 2021

In the 4th Industrial Revolution, the healthcare industry is undergoing a paradigm shift from post-care and management systems based on diagnosis and treatment to disease prevention and management based on personal precision medicine. To optimize medical services for individual patients, an open ecosystem for the healthcare industry that allows the exchange and utilization of personal health records (PHRs) is required. However, under the current system of hospital-centered data management, it is difficult to implement the linking and sharing of PHRs in practice. To address this problem, in this study, we present the design and implementation of a patient-centered PHR platform using blockchain technology. This platform achieved transparency and reliability in information management by eliminating the risk of leakage and tampering/altering personal information, which could occur when using a PHR. In addition, the patient-consent system was applied to a PHR; thus, the patient acted as the user with ownership. The proposed blockchain-based PHR platform enables the integration of personal medical information with scattered distribution across multiple hospitals, and allows patients to freely use their health records in their daily lives and emergencies. The proposed platform is expected to serve as a stepping stone for patient-centered healthcare data management and utilization.

• Journal of Adhesion and Interface
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• v.11 no.1
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• pp.35-40
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• 2010

In this study, solvent based polyurethane (PU) adhesives were prepared with the hydrocarbon resin and the acrylic modified hydrocarbon resin contents. The solvent based PU adhesive were increased with increasing tackifier concentration. The surface state of films showed good compatibility with increasing the PX-95 concentration but A-1100 series didn't present homogeneous phase more than 10 phr. Mechanical strength and peel strength were maximum at 5 phr tackifier concentration especially PX-95 series in solvent based PU adhesive.

• Polymer(Korea)
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• v.31 no.1
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• pp.80-85
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• 2007

Maleic anhydride (MA) modified ethylene-propylene-diene terpolymer (MEPDM) was pre-pared from solution polymerization. MEPDM-g-PST copolymer was prepared by melt polymerization of male ate d EPDM and quaternary ammonium silyl polydimethylsiloxane -7,7,8,8- tetracyanoquinodimethane (TCNQ) adduct (PST) in internal mixer and MEPDM-g-PST/HDPE/CB (MPEC) was prepared by com-pounding HDPE, MEPDM-g-PST copolymer and carbon black (CB, 5, 10, 15, and 20 phr), and HDPE/ CB (PEC) by compounding HDPE and CB (5, 10, 15, and 20 phr), respectively. The structure of MEPDM-g-PST copolymer was confirmed by measuring the FTIR. The maximum grafting ratio of MA onto EPDM was 2.35%. The thermal and mechanical properties of the composites were measured and dispersion characteristics of CB in matrix show that CB in MPEC was better dispersed than that in PEC composite.

• Elastomers and Composites
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• v.8 no.1
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• pp.33-51
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• 1973

We have studied the blending effects of Diene NF 35 R and Alfin 1530 at various blending ratios, 100/0, 70/30, 50/50, 30/70, 0/100, and of carbon black HAF-HS and ISAF-HS at various compounding ratios of 45 PHR, 55 PHR, 65 PHR, for tyre tread rubber. As the results, it was found that; 1. For tyre tread rubber, as the blending ratio, AR 1530/Diene NF 35R, indicated 70/30, the physical properties we examined were most excellent. 2. Excellent result was obtained in the case of carbon black compounding ratio of 55 PHR. The compounding of ISAF-HS made better result than that of HAF-HS for tensile strength, but the compounding of HAF-HS made better result than that of ISAF-HS for tearing strength and best result for abrasion quantity. 3. Heat buildup obtained from compounding carbon black HAF-HS indicated low temperature than that from compounding carbon black HAP-HS. As the compounding amount of carbon black increased, and as the blending amount of AR 1530 decreased, the heat buildup increased. 4. Carbon black was more efficient to AR 1630 than io Diene NF 35 R. 5. In the physical properties, mooney viscosity and mooney scorch time, as the compounding amount of carbon black increased, the values of mooney viscosity increased, but that of mooney scorch time had a max. point at the compoundiug amount of carbon black, 55 PHR.

• Polymer(Korea)
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• v.27 no.5
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• pp.421-428
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• 2003

The kinetics of photoinitiated polymerization of reactive oligomer methacrylates and oligomer methacrylate/SBS blends have been studied to characterize the diffusion-controlled reaction using Fourier Transform Infrared Spectroscopy-Attenuated Total Reflectance (ATR-FTIR). The polymerization rates of reactive oligomer methacrylates and oligomer methacrylate/SBS blends were autocatalytic in nature at the initial stage and then a retardation of the reaction conversion occurred gradually as the polymer matrix became vitrified, and finally the reaction became diffusion controlled. Photopolymerization behavior of methacrylate/SBS blends was well predicted using the diffusion-controlled reaction model. N-Vinyl-2-pyrrolidinone (NVP) as a reactive solvent was used to incorporate SBS into methacrylate to form semi-IPN via photopolymerization. Due to the high reactivity of NVP, polymerization rate increased with the increase of NVP content. As the content of NVP-SBS in the blends increased up to 10 phr, the reaction conversion maintained almost constant. But above 20 phr of NVP-SBS in the blends, the reaction conversion gradually decreased since the increase of viscosity affected on the photopolymerization rate. The semi-IPN films of methacrylate/SBS blends were transparent at room temperature as well as at increased temperature and were able to be applied to surface coating.

• Polymer(Korea)
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• v.26 no.2
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• pp.245-252
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• 2002

Thermodynamics and gas transport properties of polymethylmethacrylate (PMMA) blends with polyvinylmethylether (PVME) containing various amount of poly (styrene-b-methylmethacrylate) copolymer (P(S-b-MMA)) as a compatibilizer were studied. To extract interaction energies of binary pairs involved in the blends from the phase separation temperatures using an equation-of-state theory, PVME blends with methylmethacrylate copolymers containing various amount of styrene (SMMA) were prepared. PVME formed miscible blends with methylmethacrylate copolymers containing more than 70 wt% styrene and these miscible blonds showed a LCST-type phase separation behavior. Based on the interaction information obtained here, P(S-b-MMA) copolymer was added to the PMMA/PVME blends to enhance their compatibility. The average diameter of the dispersed rubber particles was gradually decreased for the blends of containing P(S-b-MMA) from 0 to 5 phr and then leveled off at a fixed size. At a fixed bland composition, the gas permeation was also increased as the P(S-b-MMA) content increased from 0 to 5 phr and then leveled off when the P(S-b-MMA) content was higher than 5 phr.

• Journal of the Korea Society of Computer and Information
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• v.25 no.8
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• pp.81-87
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• 2020

In this paper, proposes a health status monitoring system for socially marginalized elderly households living alone. This system is implemented by collecting various PHR biometric signals and residential environment information through IoT devices. In addition, the company aims to establish a basic infrastructure that can understand the situation of lonely deaths and implement prevention programs by strengthening the predictive ability through data analysis of the DB server based on PHR and information collected from IoT sensors. The sensor consists of an environmental information collection sensor and a noncontact and wearable sensor for biometric signal collection. A gateway is required to transmit the collected data to the server, and the prototype is presented in this paper. The paper has a discussion purpose of policy task for expanding medical welfare service. The results of this study are believed to help expand services to the socially marginalized and improve the medical environment of the people.

• Elastomers and Composites
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• v.41 no.2
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• pp.79-87
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• 2006

This study are conducted for the purpose of developing rubber material with noise and crack resistance. Cure characteristics, physical properties, thermal resistance, fuel resistance, abrasion resistance, crack resistance and noise resistance of NBR compounds with the various amounts of oleamide and aramid chip were investigated. From the measurements of cure characteristics and Mooney viscosities, cure characteristics of uncured rubber showed that a torque was decreased as the amount of oleamide increased. Hardness, modulus and elongation of rubber specimens tended to be reduced gradually, however, tensile strength remained unchanged as the amount of the oleamide increased. As a testing results of heat resistance for 70 hours at $120^{\circ}C$ and oil resistance far 70 hours at $40^{\circ}C$, tensile strength and elongation were all reduced. From the TGA/DSC analysis, there was no such a change observed in thermal characteristics of rubber materials. As a result of testing basic physical properties, abrasion resistance, noise resistance and crack resistance, the optimum ratio of oleamide to NBR was found to be 3 phr, while that of aramid to NBR 227001 was 1 phr.