• Journal of Satellite, Information and Communications
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• v.11 no.1
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• pp.26-31
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• 2016

In this paper, we proposed a scheme to mitigate noises based on the EMD scheme for heterogeneous communication systems. Noise-corrupted data can be decomposed into a finite number of IMF components. Using the EMD method, we can mitigate noise with eliminate noise-corrupted IMF components. We proposed iteration stop rule for reduce EMD computation time. Simulation results show that proposed EMD scheme based on proposed algorithm for iteration stop rule efficiently mitigates 3 types of noise and reduces its computational time.

• Journal of Intelligence and Information Systems
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• v.4 no.1
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• pp.115-131
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• 1998

Customer service process is one of the most important processes in today's competitive business environment. Among the various activities of customer service process, equipment malfunction diagnosis activity should be performed fast and accurately. When a customer calls the service center and reports the observed symptoms, he/she describes them in layman's terms. Therefore, the customer-reported symptoms have not been considered helpful information for service representatives. However, in order to perform diagnosis activity fast and accurately, we need to make use of the customer-reported symptoms actively. In this research, we developed three systems called R-EMD (Rule-based Equipment Malfunction Diagnostic system), C-EMD (Case-based Equipment Malfunction Diagnostic system) and R&C-EMD (Rule & Case-based Equipment Malfunction Diagnostic system), each of which diagnoses equipment malfunctions using the customer-reported symptoms. R&C-EMD is a hybrid system that utilizes both rule-based and case-based technologies. The diagnosis rules used in R&C-EMD and R-EMD were not acquired from service manuals or interviews with service representatives. Rater, we extracted them directly from the past diagnosis cases based on symptoms' frequencies. By this way, we were able to overcome the knowledge acquisition bottleneck. Using the real 100 malfunction diagnosis cases, we evaluated the performances of R&C-EMC, R-EMD and C-EMD in terms of speed and accuracy. In diagnosis time, R&C-EMD took longer than R-EMD and shorter than C-EMD. However, R&C-EMC was the best in accuracy.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.19 no.2
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• pp.279-286
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• 2015

EMD is a fully data-driven signal processing method without using any predetermined basis function and requiring any user parameters setting. However EMD experiences a problem of mode mixing which interferes with decomposing the signal into similar oscillations within a mode. To overcome the problem, EEMD method was introduced. The algorithm performs the EMD method over an ensemble of the signal added independent identically distributed white noise of the same standard deviation. Even so EEMD created problems when the decomposition is complete. The ensemble of different signal with added noise may produce different number of modes and the reconstructed signal includes residual noise. This paper propose an modified EEMD method to overcome mode mixing of EMD, to provide an exact reconstruction of the original signal, and to separate modes with lower cost than EEMD's. The experimental results show that the proposed method provides a better separation of the modes with less number of sifting iterations, costs 20.87% for a complete decomposition of the signal and demonstrates superior performance in the signal reconstruction, compared with EEMD.

• Korean Journal of Crystallography
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• v.14 no.2
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• pp.79-83
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• 2003

The microstructure of bulk electrolytic MnO₂ (EMD) was studied using x-ray diffraction and transmission electron microscopy (TEM). The bulk sample showed a typical powder x-ray diffraction pattern of EMD materials. TEM study showed that the structure of EMD is present at two length scales;grains, ∼0.2 ㎛ in diameter, and ∼10 nm crystallites within the grain. The electron beam microdiffraction study revealed that each grain is an assemblage of multiphase with a common crystallographic orientation, and_that ∼50% of the crystallites are Ramsdellite, ∼30% are ε-MnO₂, and ∼15% are Pyrolusite. The ｛1120｝peak located at about 67° in powder XRD pattern as well as a high-resolution electron microscope (HREM) image of (0001) plane support the existence of ε-MnO₂ phase.

• Restorative Dentistry and Endodontics
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• v.39 no.3
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• pp.187-194
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• 2014

Objectives: The effects of bone morphogenetic protein-2 (BMP-2) and enamel matrix derivative (EMD) respectively with mineral trioxide aggregate (MTA) on hard tissue regeneration have been investigated in previous studies. This study aimed to compare the osteogenic effects of MTA/BMP-2 and MTA/EMD treatment in MC3T3-E1 cells. Materials and Methods: MC3T3-E1 cells were treated with MTA (ProRoot, Dentsply), BMP-2 (R&D Systems), EMD (Emdogain, Straumann) separately and MTA/BMP-2 or MTA/EMD combination. Mineralization was evaluated by staining the calcium deposits with alkaline phosphatase (ALP, Sigma-Aldrich) and Alizarin red (Sigma-Aldrich). The effects on the osteoblast differentiation were evaluated by the expressions of osteogenic markers, including ALP, bone sialoprotein (BSP), osteocalcin (OCN), osteopontin (OPN) and osteonectin (OSN), as determined by reverse-transcription polymerase chain reaction analysis (RT-PCR, AccuPower PCR, Bioneer). Results: Mineralization increased in the BMP-2 and MTA/BMP-2 groups and increased to a lesser extent in the MTA/EMD group but appeared to decrease in the MTA-only group based on Alizarin red staining. ALP expression largely decreased in the EMD and MTA/EMD groups based on ALP staining. In the MTA/BMP-2 group, mRNA expression of OPN on day 3 and BSP and OCN on day 7 significantly increased. In the MTA/EMD group, OSN and OCN gene expression significantly increased on day 7, whereas ALP expression decreased on days 3 and 7 (p < 0.05). Conclusions: These results suggest the MTA/BMP-2 combination promoted more rapid differentiation in MC3T3-E1 cells than did MTA/EMD during the early mineralization period.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.13 no.12
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• pp.2671-2676
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• 2009

Empirical mode decomposition (EMD) is new time-frequency analysis method to decompose the signal adaptively and efficiently. The key idea of EMD is to decompose the signal into a set of functions defined by the signal itself, named Intrinsic Mode Functions (IMFs), which preserve the inherent properties of the original signal. Since the decomposition is based on the local time scale of the signal, it is not only applicable to nonlinear and non-stationary processes but also useful in biomedical signals like electrocardiogram (ECG). Traditional low-pass filter uses fourier transform to analysis signal in frequency domain, but EMD is filtered to maintain signal properties in time domain. This paper performed signal decomposition and filtering for noisy ECGs using EMD method. The proposed method is presented and compared with traditional low-pass filter by two performance indices. Our results show effectiveness for enhancement of the noisy ECG waveforms.

• The Journal of Advanced Prosthodontics
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• v.6 no.5
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• pp.406-414
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• 2014

PURPOSE. The objective of this study was to investigate the biologic effects of enamel matrix derivative (EMD) with different concentrations on cell viability and the genetic expression of human gingival fibroblasts (HGF) to zirconia surfaces. MATERIALS AND METHODS. Immortalized human gingival fibroblasts (HGF) were cultured (1) without EMD, (2) with EMD $25{\mu}g/mL$, and (3) with EMD $100{\mu}g/mL$ on zirconia discs. MTT assay was performed to evaluate the cell proliferation activity and SEM was carried out to examine the cellular morphology and attachment. The mRNA expression of collagen type I, osteopontin, fibronectin, and TGF-${\beta}1$ was evaluated with the real-time polymerase chain reaction (RT-PCR). RESULTS. From MTT assay, HGF showed more proliferation in EMD $25{\mu}g/mL$ group than control and EMD $100{\mu}g/mL$ group (P<.05). HGFs showed more flattened cellular morphology on the experimental groups than on the control group after 4h culture and more cellular attachments were observed on EMD $25{\mu}g/mL$ group and EMD $100{\mu}g/mL$ group after 24h culture. After 48h of culture, cellular attachment was similar in all groups. The mRNA expression of type I collagen increased in a concentration dependent manner. The genetic expression of osteopontin, fibronectin, and TGF-${\beta}1$ was increased at EMD $100{\mu}g/mL$. However, the mRNA expression of proteins associated with cellular attachment was decreased at EMD $25{\mu}g/mL$. CONCLUSION. Through this short term culture of HGF on zirconium discs, we conclude that EMD affects the proliferation, attachment, and cell morphology of HGF cells. Also, EMD stimulates production of extracellular matrix collagen, osteopontin, and TGF-${\beta}1$ in high concentration levels. CLINICAL RELEVANCE. With the use of EMD, protective barrier between attached gingiva and transmucosal zirconia abutment may be enhanced leading to final esthetic results with implants.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.31 no.4
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• pp.281-286
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• 2009

Introduction: Enamel matrix derivative (EMD) is a protein which is secreted by Hertwig root sheath and plays a major role in the formation of cementum and attachment of peridontium. Several studies have shown that EMD promoted the proliferation and differentiation of preosteoblasts, osteoblasts and periodontal ligament cells in vitro: however, reports showing the inhibition of osteogenic differentiation by EMD also existed. This study was designed to simultaneously evaluate the effect of EMD on the two cell lines (human mesenchymal stem cells: hMSC, human periodontal ligament derived fibroblasts: hPDLCs) by means of quantitative analysis of some bone related matrices (Alkaline phosphatase : ALP, osteopontin ; OPN, osteocalcin ; OC). Materials and Methods: hMSCs and hPDLCs were expanded and cells in the 4${\sim}$6 passages were adopted to use. hMSc and hPDLCs were cultured during 1,2,7, and 14 days with 0, 50 and 100 ${\mu}g/ml$ of EMD, respectively. ALP activity was assessed by SensoLyte ALP kit and expressed as values of the relative optical density. Among the matrix proteins of the bony tissue, OC and OPN were assessed and quantification of these proteins was evaluated by means of human OC immunoassay kit and human OPN assay kit, respectively. Results: ALP activity maintained without EMD at $1,2^{nd}$ day. The activity increased at $7^{th}$ day but decreased at $14^{th}$ day. EMD increased the activity at $14^{th}$ day in the hPDLCs culture. In the hMSCs, rapid decrease was noted in $7^{th}$ and $14^{th}$ days without regard to EMD concentrations. Regarding the OPN synthesis in hPDLCs, marked decrease of OPN was noted after EMD application. Gradual decrease tendency of OPN was shown over time. In hMSCs, marked decrease of OPN was also noted after EMD application. Overall concentration of OPN was relatively consistent over time than that in hPDLCs. Regarding the OC synthesis, in both of hPDLCs and hMSCs, inhibition of OC formation was noted after EMD application in the early stages but EMD exerted minimal effect at the later stages. Conclusion: In this experimental condition, EMD seemed to play an inhibitory role during the differentiation of hMSCs and hPDLCs in the context of OC and OPN formation. In the periodontium, there are many kinds of cells contributing to the regeneration of oral tissue. EMD enhanced ALP activity in hPDLCs rather than in hMSCs and this may imply that EMD has a positive effect on the differentiation of cementoblasts compared with the effect on hMSCs. The result of our research was consistent with recent studies in which the authors showed the inhibitory effect of EMD in terms of the differentiation of mineral colony forming cells in vitro. This in vitro study may not stand for all the charateristics of EMD; thus, further studies involving many other bone matrices and cellular attachment will be necessary.

• The Korean Journal of Emergency Medical Services
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• v.6 no.1
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• pp.27-37
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• 2002

The health and medical service attracts more public attention as the economy of Korea is rapidly growing up and the standard of living is elevated. Especially, the interest and demand on the prehospital emergency medical service that consists of the important part of primary medical service that is directly related to the life of patients are gradually increased. However, as compared with other advanced countries such as America in this area, Korea actually fell behind in the utilization of IT (Information Technology) to maximize the efficiency of emergency service system as well as has a problem in the general service system. This study suggested the necessity to introduce EMD (Emergency Medical Dispatch) system that takes a great role as the core part in the prehospital emergency medical service that is not systemized in Korea yet. In addition, this study proposed the implementation model of EMD ASP system using ASP (Application Service Provider) in EMD system to flexibly deal with the change of IT and efficient implementation and integration of information system as well as to significantly reduce cost through wire/wireless high speed Internet network that is politically promoted in Korea on the basis of EMD. The system analysis and design was executed by HIPO (Hierarchy Plus Input Process Output) analysis that was the conceptual design technology for EMD information system modeling based on ASP and DFD (Data Flow Diagram). This study proposed DB table configuration and data schema to implement the application of web browser interface in EMD system through ERD(ER-Diagram) of EMD ASP system. Finally, this study described how to implement and utilize EMD information system. This study aims to facilitate the qualitative development of emergency medical service in the future as suggesting the concrete models for the implementation of high value-added prehospital emergency medical information system as applying ASP concept to EMD system of prehospital emergency medical service area.

• Restorative Dentistry and Endodontics
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• v.38 no.4
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• pp.194-203
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• 2013

Objectives: To investigate the effect of enamel matrix derivative (EMD) on periodontal healing of replanted teeth in animal models. Materials and Methods: The authors searched MEDLINE, PubMed, EMBASE, Cochrane Library, Web of Knowledge and Scopus for articles published up to Oct 2012. Animal studies in which EMD was applied in transplanted or replanted teeth with adequate controls and histological data were considered. Normal periodontal healing or root resorption determined by histology after EMD was applied in replanted teeth with adequate controls was used as outcome measures. The following search strategy was used: ('Emdogain' OR 'enamel matrix proteins' OR 'enamel matrix derivative') AND ('avulsion' OR 'transplantion' OR 'autotransplantation' OR 'replantation'). Results: Six animal studies were included in the final review. There was great heterogeneity in study design among included studies. Two studies with similar study designs were identified and analyzed by a meta-analysis. The pooled estimates showed a significantly higher normal healing and surface resorption and significantly less inflammatory and replacement resorption in EMD-treated groups compared with non-EMD-treated groups. Conclusions: With the limitations of this systematic review, the use of EMD led to greater normal periodontal healing and surface root resorption and less inflammatory and replacement root resorption in the presence of periodontal ligaments. However, no definite conclusion could be drawn with regard to the effect of EMD on periodontal healing and root resorption when no periodontal ligaments exist.