• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.8
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• pp.5393-5399
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• 2014

To examine the effects of a mycosporine-like amino acids (MAAs) mixture from microalgae, Chlamydomonas sp, on the anti-wrinkle activities, the expression levels of genes that are associated with skin aging, including type I procollagen, elastin and involucrin, were analyzed. Asterina 330+palythine (A+P) and shinorine+palythine (S+P) mixtures were purified from Chlamydomonas sp using the following steps: 80% methanolic extraction, column purification, and HPLC analysis. As a result of the MTT assay, A+P and S+P did not induce cellular cytotoxicity with up to 0.1 mg/mL of both MAAs. In addition, the treatment of UV-exposed fibroblasts with A+P (0.05 mg/mL) and S+P (0.01 mg/mL) increased the levels of the PCOLCE mRNAs by 2.7 and 3.6 fold compared to the control group, respectively, The levels of elastin gene expression were elevated 5.59 and 3.1 fold in the A+P and S+P treated (0.01 mg/mL) cells, respectively. In particular, at a concentration of 0.01 mg /mL, the A+P and S+P expression levels of Involucrin mRNAs were increased 3.5 and 2.5 fold in the UV-exposed cells compared to the control, respectively. In conclusion, the MAAs derived from Chlamydomonas sp can be utilized as functional cosmetic materials with anti-wrinkle effects on the skin.

• Fire Science and Engineering
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• v.27 no.4
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• pp.27-34
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• 2013

The high prediction performance of fire detector models is essentially needed to assure the reliability of fire and evacuation modeling in the process of PBD (Performance Based fire safety Design). The main objective of the present study is to measure input information in order to predict the accurate activation time of smoke detector into a Large Eddy Simulation (LES) fire model such as FDS (Fire Dynamics Simulator). To end this, FDE (Fire Detector Evaluator) which can measure the device properties of detector was developed, and the input information of Heskestad and Cleary's models was measured for a ionization smoke detector. In addition, the activation times of smoke detectors predicted using default values into FDS and measured values in the present study were systematically compared. As a result, the device properties of smoke detector examined in the present study showed a significant difference compared to the default values used into FDS, which resulted in the considerable difference of up to 15 minutes or more in terms of the activation time of smoke detector. The database (DB) on device properties of various smoke and heat detectors will be built to improve the reliability of PBD in future studies.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.2
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• pp.745-754
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• 2021

The purpose of this study was to evaluate and verify the effectiveness of sustainable cosmetic raw materials developed from Gynostemma pentaphyllum, a plant native to Ulleungdo, in improving the skin barrier function and treating atopic dermatitis. Cells were derived from adult Gynostemma pentaphyllum plants, and suitable conditions for mass culture of the cells were established in a bioreactor. DNA components and amino acids extracted from this mass culture were identified from the HPLC fraction. In the in vitro efficacy evaluation results, changes in the expression levels of skin barrier-related proteins such as filaggrin (FLG) and Zonula occludens-1 (Zo-1) were insignificant. It was confirmed that the expression levels of the proteins thymic stromal lymphopoietin (TSLP) and interleukin-33 (IL-33) were significantly reduced. These results lead to the conclusion that Gynostemma pentaphyllum cell extracts have significant anti-inflammatory effects and that these extracts can be widely used as sustainable, nature-friendly active material in cosmetics with anti-inflammatory effects and targeted at improving atopic dermatitis.They may find use in anti-aging cosmetic products as well.

• Phonetics and Speech Sciences
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• v.15 no.4
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• pp.91-100
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• 2023

Reverberation time (T60) is a typical acoustic parameter that provides information about reverberation. Since the impacts of reverberation vary depending on the frequency bands even in the same space, frequency-dependent (FD) T60, which offers detailed insights into the acoustic environments, can be useful. However, most conventional blind T60 estimation methods, which estimate the T60 from speech signals, focus on fullband T60 estimation, and a few blind FDT60 estimation methods commonly show poor performance in the low-frequency bands. This paper introduces a modified approach based on Attentive pooling based Weighted Sum of Spectral Decay Rates (AWSSDR), previously proposed for blind T60 estimation, by extending its target from fullband T60 to FDT60. The experimental results show that the proposed method outperforms conventional blind FDT60 estimation methods on the acoustic characterization of environments (ACE) challenge evaluation dataset. Notably, it consistently exhibits excellent estimation performance in all frequency bands. This demonstrates that the mechanism of the AWSSDR method is valuable for blind FDT60 estimation because it reflects the FD variations in the impact of reverberation, aggregating information about FDT60 from the speech signal by processing the spectral decay rates associated with the physical properties of reverberation in each frequency band.

• Fire Science and Engineering
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• v.22 no.3
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• pp.216-220
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• 2008

Water mist fire suppression system utilizes the fire suppression features such as cooling of fire source, dilution of ambient oxygen, and shielding of radiation heat with the evaporation of microscopic water droplets. The momentum of water mist is relatively lower than that of larger water droplet and the infiltration of water mist to the fire source is not effective. Contribution of evaporated water vapor is liable to decline to limited portion of fire source due to its light weight and sparse density. On the other hand, the cycling water mist pattern is expected to improve the penetration force of water mist as well as the air expelling capability with the stratified spray characteristics. At this paper, we present the analyzed fire suppression capability of intermittent water spray pattern by use of FDS which is computational fire dynamics fire model. We expect this analysis can support the basic concept to the development of the prototype of water mist nozzle.

• The Journal of Internal Korean Medicine
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• v.32 no.4
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• pp.584-598
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• 2011

Objectives : Functional dyspepsia is a type of disease characterized by bothersome postprandial fullness, early satiation, epigastric pain and burning without structural gastrointestinal disease. The aim of this study was to analyze the characteristics of functional dyspepsia patients and evaluate changes in symptoms, quality of life, and electrogastrography parameters before and after oriental medical interventions. Methods : We recruited forty-six functional dyspepsia patients who visited gastroenterology clinic in the oriental medicine hospital of Kyung Hee University between November 2009 and February 2011. Patients were assessed for their frequency of dyspepsia (based on short form-Leeds Dyspepsia Questionnaire: SF-LDQ), quality of life (based on functional dyspepsia-related quality of life questionnaire: FD-QoL), gastric motility (based on electrogastrography: EGG) on the first visit. Then, the effect of oriental medical interventions was evaluated using EGG on the second visit. Results : The majority of patients had symptoms of nausea and indigestion. The largest decrease in EGG parameters was found in the indigestion group. The frequency of regurgitation and postprandial EGG power % bradygastria showed a significant correlation. Also, significant correlations were found between some items of FD-QoL and some EGG parameters. Compared to the EGG parameters before oriental medical interventions, some parameters after treatment had positive results, implying the improvement of gastric motility disorder. We also found improvement of EGG parameters in both digestant medicinal group and digestant combined with qi-tonifying medicinal group. Conclusions : The results of this study suggest that clinical application of EGG can be an objective diagnostic tool in functional dyspepsia patients visiting oriental medical hospital.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.12C
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• pp.1020-1028
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• 2010

Relay has attracted great attention due to its inherent capability to extend the service coverage and combat shadowing in next generation mobile communication systems. So far, most relay technologies have been developed under the half-duplex (HD) constraint that prevents relays from transmitting and receiving at the same time. Although half-duplex relay (HDR) is easy to implement, it requires partitioning of resource for transmission and reception, reducing the whole system capacity. In this paper, we propose a multinser precoding and power control scheme with sum rate matching for a full-duplex (FD) multiple-input multiple-output (MIMO) relay. Full-duplex relay (FDR) can overcome the drawback of HDR by transmitting and receiving on the same frequency at the same time, while it is crucial to reduce the effect of self-interference that is caused by its own transmitter to its own receiver. The proposed precoding scheme cancels the self-interference of the FDR as well as to support multiuser MIMO. Moreover, we suggest a power allocation scheme for FD MIMO relay with the constraint that the sum rate of the relay's received data streams is equal to that of the relay's transmit data streams.

• Journal of the Korean Association of Geographic Information Studies
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• v.21 no.2
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• pp.56-67
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• 2018

In general, fire and evacuation simulators are used independently to diagnose the safety of building. Because this method does not reflect the movement of pedestrians considering fire spread, it is difficult to expect diagnosis of safety with high accuracy. In this study, we propose the simulation method that can describe the movement of pedestrians in the fire emergency. Our method reflects the FDS fire spread data into FFM and explains the situation in which a pedestrian recognize a fire and escapes to a safe route. This study consists of data linkage between FDS and FFM and development of improved FFM. Experiment of the proposed method is progressed using the EgresSIM. Simulation result shows that the number of evacuees on each exit is affected by the presence or absence of fire and it was confirmed that the evacuation time increase and the bottleneck phenomenon deepened by exit.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.11 no.6
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• pp.2831-2847
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• 2017

In this paper, a joint destination-relay selection and antenna mode selection scheme for full-duplex (FD) relay network is investigated, which consists of one source node, N FD amplify-and-forward (AF) relays and M destination nodes. Multiple antennas are configured at the source node, and beamforming technique is adopted. Two antennas are employed at each relay, one for receiving and the other for transmitting. Only one antenna is equipped at each destination node. In the proposed scheme, the best destination node is firstly selected according to the direct links between the source node and destination nodes. Then the transmit and receive mode of two antennas at each relay is adaptively selected based on the relaying link condition. Meanwhile, the best relay with the optimal Tx/Rx antenna configuration is selected to forward the signals. To characterize the performance of the proposed scheme, the closed-form expression of the outage probability is derived; meanwhile, the simple asymptotic expressions are also obtained. Our analysis shows that the proposed scheme obtains the benefits of multi-relay diversity and multi-destination diversity. Moreover, extra space diversity in the medium SNR region can be achieved due to the antenna selection at the relay. Finally, Monte-Carlo simulations are provided to consolidate the analytical results, and show the effectiveness of the proposed scheme.

• The KIPS Transactions:PartB
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• v.14B no.1 s.111
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• pp.59-64
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• 2007

In these days, malicious codes have become reality and evolved significantly to become one of the greatest threats to the modern society where important information is stored, processed, and accessed through the internet and the computers. Computer virus is a common type of malicious codes. The standard techniques in anti-virus industry is still based on signatures matching. The detection mechanism searches for a signature pattern that identifies a particular virus or stain of viruses. Though more accurate in detecting known viruses, the technique falls short for detecting new or unknown viruses for which no identifying patterns present. To cope with this problem, anti-virus software has to incorporate the learning mechanism and heuristic. In this paper, we propose a fuzzy diagnosis system(FDS) using fuzzy c-means algorithm(FCM) for the cluster analysis and a decision status measure for giving a diagnosis. We compare proposed system FDS to three well known classifiers-KNN, RF, SVM. Experimental results show that the proposed approach can detect unknown viruses effectively.