• Transactions on Electrical and Electronic Materials
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• v.11 no.2
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• pp.69-72
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• 2010

This study investigates the thermal and mechanical properties of insulation elements through the mixing of epoxy based micro and nano particles. Regarding their thermal properties, differential scanning calorimeter and dynamic mechanical analyser were used to calculate the cross-linking densities for various types of insulation elements. The mechanical properties of the bending strength, the shape and scale parameters, were obtained using the Weibull plot. This study obtained the best results in the scale parameters, at 0.5 phr, for the bending strength of the epoxy nano-and-micro mixture composites.

• Polymer(Korea)
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• v.24 no.3
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• pp.358-365
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• 2000

Miscibility itnd thermal behavior of blends of synthetic biodegradable aliphatic polyester (Bionolle) with poly(epichlorohydrin) (PECH) were investigated by a differential scanning calorimetry (DSC), a dynamic mechanical thermal analyzer (DMTA) and a rotational rheometer. Observed both single glass transition temperatures from the DSC in agreement with the Fox equation and single T$_{g}$ changes as a function of composition from the DMTA indicate that these blend mixtures are miscible. In addition, the miscibility of this blend system was also observed from the single curve of the Cole-Cole Plot of log G′($\omega$) vs. log C"($\omega$) from the dynamic test using a rotational rheometer. This was further verified from the cryogenically fractured surface of BDP/PECH blends by scanning electron microscopy.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.249.1-249.1
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• 2003

The objective of the study was to develop an oral delivery system to increase the stability and efficacy of iron casein succinylate. Aqueous nanoparticles were prepared using complex coacervation of the oppositely charged chitosan and iron casein succinylate with polyethyleneglycol (PEG). The physicochemical properties of nanoparticles were investigated using dynamic light scattering, zeta potential and scanning electron microscopy. Chitosan-iron casein succinylate interactions were investigated in solid state by differential scanning calorimetry (DSC) and FT-IR spectrometry. (omitted)

• Proceedings of the KSME Conference
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• 2005.11a
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• pp.239.1-239.1
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• 2005

• Journal of the Korean Society for Precision Engineering
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• v.10 no.3
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• pp.152-160
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• 1993

This paper presents experimental study of the static and dynamic fracture toughness behavior of a A1-6061 aluminum alloy reinforced alumina( .delta. -A1$_{2}$0$_{3}$) whiskers with 5%, 10%, 15% volume fraction. The static fracture tests using three-point bending specimen were performed by UTM25T. And drop weight impact tester performing dynamic fracture tests was used to measure dynamic locads applied to a fatigue-precracked specimes. The oneset of crack initiation was detected uwing a strain gage bonded near a crack tip. The value of static fracture toughness $K_{IC}$ and dynamic fracture toughness $K_{ID}$ were decided on the basis of linear elastic fracture mechanics. The effects of fiber volume fraction and loading on fracture toughness were investigated. The distribution of whiskers, bonding state and fracture interfaces involved in void, fiber pull-out state were investigated by optical microscopy(OM) and scanning electron microscopy(SEM)

• Elastomers and Composites
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• v.53 no.2
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• pp.52-56
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• 2018

The present study examines the transformation of dynamic DSC data into the equivalent isothermal data for the formation kinetics of a polyurethane elastomer. The reaction of 2'-dichloro-4,4'-methylenedianiline (MOCA) with a PTMG/TDI-based isocyanate prepolymer was evaluated. DSC measurement was performed in the dynamic scanning mode with several different heating rates to obtain the reaction thermograms. Then, the data was transformed into the isothermal data through a procedure based on Ozawa analysis. The main feature of this procedure was the transformation of $({\alpha}-T)_{\beta}$ curves from dynamic DSC into $({\alpha}-t)_T$ curves using the isoconversional $(t-T)_{\alpha}$ diagram. Validity was discussed for the relationship between the dynamic DSC data and the transformed isothermal results.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.17 no.6
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• pp.1635-1656
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• 2023

In Bayesian multi-target tracking, the Poisson multi-Bernoulli mixture (PMBM) filter is a state-of-the-art filter based on the methodology of random finite set which is a conjugate prior composed of Poisson point process (PPP) and multi-Bernoulli mixture (MBM). In order to improve the random finite set-based filter utilized in multi-target tracking of sensor scanning, this paper introduces the Poisson multi-Bernoulli mixture filter into time-matching Bayesian filtering framework and derive a tractable and principled method, namely: the time-matching Poisson multi-Bernoulli mixture (TM-PMBM) filter. We also provide the Gaussian mixture implementation of the TM-PMBM filter for linear-Gaussian dynamic and measurement models. Subsequently, we compare the performance of the TM-PMBM filter with other RFS filters based on time-matching method with different birth models under directional continuous scanning and out-of-order discontinuous scanning. The results of simulation demonstrate that the proposed filter not only can effectively reduce the influence of sampling time diversity, but also improve the estimated accuracy of target state along with cardinality.

• Composites Research
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• v.27 no.3
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• pp.90-95
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• 2014

Cure shrinkage during cure process of polymer matrix composites develope residual stress that cause some structural deformation, such as spring-in, spring-out and warpage. The carbon/epoxy prepreg used in this study is Hexply M21EV/34%/UD268NFS/IMA-12K supplied by Hexcel corp. Cure shrinkage and degree of cure measured by TMA(thermomechanical analyzer) and DSC(differential scanning calorimetry). Cure shrinkages are measured by TMA within a temperature range of $140{\sim}240^{\circ}C$ in a nitrogen atmosphere, and degree of cure determined by the heat of reaction using dynamic and isothermal DSC runs in argon atmosphere. As a result, the cure shrinkage is increased dramatically in a degree of cure range between 27~80%. the higher the cure temperature, the lower the degree of cure occurring to begin cure shrinkage.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.33 no.6A
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• pp.624-634
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• 2008

The mobile station which is about to do handover in IEEE 802.16e networks scans its neighboring base station channels to decide its next target base station. However, due to the lack of location information of its subscribers, the serving base station cannot provide any reliable candidate channel which is actually attachable by the scanning mobile stations, which makes the mobile station suffer from the long scanning time. Sometimes, long scanning time may cause the degradation of quality of service due to repeatable scan-duration or failure to start the handover procedure in time. To overcome these problems, in this paper, we propose a new protocol so called fast group scanning scheme, in which multiple mobile stations form a group to scan their neighboring base station channels simultaneously. Main contribution of this proposal is to find and decide a reliable target base station within a short scanning time. The fast group scanning scheme can be deployed to the cell network of the serving base station with a dynamic neighboring base station list management.

• Applied Microscopy
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• v.45 no.4
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• pp.214-217
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• 2015

This study introduces metal coating as an effective sample preparation method to remove charge-up caused by the shadow effect during field emission scanning electron microscope (FE-SEM) analysis of dynamic structured samples. During a FE-SEM analysis, charge-up occurs when the primary electrons (input electrons) that scan the specimens are not equal to the output electrons (secondary electrons, backscattered electrons, auger electrons, etc.) generated from the specimens. To remove charge-up, a metal layer of Pt, Au or Pd is applied on the surface of the sample. However, in some cases, charge-up still occurs due to the shadow effect. This study developed a coating method that effectively removes charge-up. By creating a converted sample stage capable of simultaneous tilt and rotation, the shadow effect was successfully removed, and image data without charge-up were obtained.