• The Transactions of the Korean Institute of Electrical Engineers B
• /
• v.50 no.8
• /
• pp.374-383
• /
• 2001

This paper presents the torque estimation scheme by Energy Conversion Method (ECM) that can be applied to the torque control of switched reluctance motor. There are two types of torque estimation method by ECM. One is the method using mechanical output energy and another is that using co-energy. When the torque is estimated by ECM, the estimated flux linkage can be obtained by voltage equation and Luenberger observer. By comparing the torque estimated by ECM with that be FEM, we verify the feasibility of the proposed torque estimation by ECM.

• Journal of Ecology and Environment
• /
• v.32 no.1
• /
• pp.13-18
• /
• 2009

This study was conducted to investigate ectomycorrhizal (ECM) diversity on Pinus densiflora seedlings in a disturbed pine forest. Pine seedlings less than one year old were collected from disturbed and undisturbed sites in the Mt. Songni region. The belowground ECM fungal communities colonizing P. densiflora seedlings were studied using morphotyping and DNA sequencing. The relative abundance of ECM root tips was significantly higher in the undisturbed sites than in the disturbed sites, and the ECM species diversity was lower in the disturbed sites than in the undisturbed sites. In addition, the ECM community composition was significantly different in the disturbed and undisturbed forest sites.

• Mycobiology
• /
• v.40 no.3
• /
• pp.168-172
• /
• 2012

In this study, the effect of soil ameliorators on ectomycorrhizal (ECM) fungal communities in coal mine spoils was investigated. Organic fertilizers and slaked lime were applied as soil ameliorators in 3 abandoned coal mine spoils. One year after the initial treatment, roots of Pinus densiflora seedlings were collected and the number of ECM species, colonization rate, and species diversity were assessed. The results showed that the soil ameliorators significantly increased ECM colonization on the roots of P. densiflora. The results suggest that soil ameliorators can have a positive effect on ECM fungi in terms of growth of host plants and show the potential use of soil ameliorator treatment for revegetation with ECM-colonized pine seedlings in the coal mine spoils.

• Journal of the Korea Institute of Military Science and Technology
• /
• v.9 no.2 s.25
• /
• pp.77-86
• /
• 2006

Usually, a tracking-gate of the tracker is used to track the target radar signal in the active ECM system. In this paper, we propose the feed-back tracking-gate filtering method. The designed method applies a tracking-gate of the tacker to the ECM system's receiver as a rejection or pass filter selected by the receiver's purpose, and the specific target signals can be passed or rejected though this tracking-gate filter. Thus, the number of input signals within the receiver's search band is minimized owing to this filter except the target signals. In conclusion, the EW equipment's reaction time can be reduced and the error value about the target signals can be lower than the previous methods'.

• Proceedings of the Korean Society of Broadcast Engineers Conference
• /
• 2022.06a
• /
• pp.1239-1240
• /
• 2022

JVET 은 VVC(Versatile Video Coding) 표준화 완료 이후 보다 높은 압축 성능을 갖는 차세대 비디오 코덱의 표준 기술을 탐색하고 있으며 ECM(Enhanced Compression Model) 참조 소프트웨어를 통해 제안된 알고리즘의 성능을 검증하고 있다. 현재 ECM 에서는 정해진 순서에 의해 병합(Merge) 후보를 구성하고 템플릿 매칭(template matching)을 통하여 후보들의 순서를 재배열하는 ARMC(Adaptive Reordering of Merge Candidate) 기법을 채택하고 있다. 본 논문은 ARMC 의 병합 후보의 선택 빈도 분석을 바탕으로 정규 병합(regular merge) 후보 수를 확장하여 구성하고, 실제 탐색에 사용되는 최종 후보의 수를 제한하는 효율적인 ARMC 후보 구성 기법을 제안한다. 실험결과 ECM 4.0 대비 Cb 와 Cr 에서 0.12%, 0.19% 비디오 부호화 성능을 확인하였다.

• The Korean Journal of Financial Management
• /
• v.16 no.1
• /
• pp.223-243
• /
• 1999

포트폴리오의 위험을 통제하거나 감소시키기 위해서 헤저들은 최적헤지비율을 추정하여야 하는데, 최적헤지비율의 추정치는 사용하는 모형에 따라 많은 차이를 보인다. 전통적인 회귀분석모형에 의하여 추정된 최적헤지비율은 시계열자료의 불안정성(nonstationary) 등으로 인하여 잘못될 가능성이 많으며, 잘못 추정된 헤지비율을 그대로 이용할 경우 현물포트폴리오의 시장위험을 최소화시키지 못하고 헤징비용을 증가시키는 결과를 초래한다. 시계열자료의 불안정성으로 말미암아 야기되는 문제점들을 개선할 수 있는 모형으로서 오차 수정모형(Error Correction Model : ECM)이 널리 이용되고 있다. 본 연구는 ECM을 사용하여 추정된 최적헤지비율과 전통적 회귀분석모형을 사용하여 추정한 최적헤지비율을 비교하여 어떤 모형으로 추정한 헤지비율이 더 정확한지를 평가하는데 목적을 두고 있다. 즉, 본 연구는 KOSPI 200 현 선물지수 자료를 대상으로 ECM과 전통적 회귀분석모형에 의한 최적헤지비율을 추정하고 각 모형의 설명력과 예측력을 비교하고자 한다. 실증분석 결과, KOSPI 200 현물지수와 KOSPI 200 선물지수간에는 공적분 관계가 존재하며, ECM과 전통적 회귀분석모형을 이용하여 추정한 최적헤지비율의 크기는 서로 다르며, ECM을 이용할 때 모형의 설명력이 조금 더 높게 나타났으며, 예측력도 ECM이 좀더 우월한 것으로 나타났다.

• Journal of Electrochemical Science and Technology
• /
• v.15 no.2
• /
• pp.220-241
• /
• 2024

Due to its unique advantages, electrochemical machining (ECM) is playing an increasingly significant role in the manufacture of difficult-to-machine materials. Most of the current ECM research is conducted at room temperature, with studies on ECM in a cryogenic environment not having been reported to date. This study is focused on the electrochemical dissolution characteristics of typical iron and nickel base alloys in NaNO₃ solution at low temperature (-10℃). The polarization behaviors and passive film properties were studied by various electrochemical test methods. The results indicated that a higher voltage is required for decomposition and more pronounced pitting of their structures occurs in the passive zone in a cryogenic environment. A more in-depth study of the composition and structure of the passive films by X-ray photoelectron spectroscopy and electrochemical impedance spectroscopy showed that the passive films of the alloys are modified at low temperature, and their capacitance characteristics are more prominent, which makes corrosion of the alloys more likely to occur uniformly. These modified passive films have a huge impact on the surface morphologies of the alloys, with non-uniform corrosion suppressed and an improvement in their surface finish, indicating that lowering the temperature improves the localization of ECM. Together with the cryogenic impact of electron energy state compression, the accuracy of ECM can be further improved.

• Journal of Microbiology and Biotechnology
• /
• v.34 no.8
• /
• pp.1711-1717
• /
• 2024

This study evaluates the efficacy of a decellularized intestine tissue-derived extracellular matrix (Intestine ECM) as a scaffold for culturing colorectal cancer (CRC) organoids and establishing cell-derived xenograft (CDX) models, comparing its performance to traditional Matrigel. Intestine ECM demonstrates comparable support for organoid formation and cellular function, highlighting its potential as a more physiologically relevant and reproducible platform. Our findings suggest that Intestine ECM enhances the mimetic environment for colon epithelium, supporting comparable growth and improved differentiation compared to Matrigel. Moreover, when used as a delivery carrier, Intestine ECM significantly increases the growth rate of CDX models using patient-derived primary colorectal cancer cells. This enhancement demonstrates Intestine ECM's role not only as a scaffold but also as a vital component of the tumor microenvironment, facilitating more robust tumorigenesis. These findings advocate for the broader application of Intestine ECM in cancer model systems, potentially leading to more accurate preclinical evaluations and the development of targeted cancer therapies.

• Journal of the Korean Institute of Landscape Architecture
• /
• v.45 no.6
• /
• pp.98-114
• /
• 2017

This study analyzed the commemorative landscapes of eight Holocaust concentration camp memorials(HCCM) of Germany and Poland from a landscape architecture point of view including historical landscape, places and remains, and monuments. A site survey was conducted at Dahau concentration camp memorial(CCM) and Bergen-Belsen CCM of Germany in September of 2015 and the Auschwitz-Birkenau extermination camp memorial(ECM), Majdanek ECM, Belzec ECM, Sobibor ECM, Treblinka ECM, Chelmno ECM of Poland in April of 2016. The results are as follows. First, the landscape of the concentration camp at Dahau CCM, Auschwitz ECM, and Majdanek ECM liberated by the Allied Forces was well conserved with the maintenance of camp facilities and the spatial structure of camps while monuments and memorials seized by sociopolitical argument were built with restriction. But Belzec ECM, Sobibor ECM, Treblinka ECM, and Chelmno ECM devastated and planted artificially to forest were overwhelmingly surrounded with natural landscape, and also, excavated relics and remains were preserved and the monuments were built at the place of memory. Second, gas chambers, crematoriums, guard posts, electric wire fences, railroads and ramps, barracks, and drainage ditches were considered to be typical facilities present in the camp structure and the gas chambers, crematoriums, human ashes, and mass graves demonstrated the horrible history of these camps and the railroad and ramp where Jewish prisoners arrived also had the strong sense of place. These remains were regarded as symbolic elements to create a memory of the tragedy and place. Third, commemoration of victims was applied as the basic concept and recalling the memory of the Holocaust was also considered very important content. Religious reconciliation and peace was represented at Dahau CCM and the Jewish identity was strongly expressed at Treblinka ECM and Belzec ECM representing the Jewish community and Judaism. Fourth, the monuments with semi-abstract styles and abstract sculptures represented the Holocaust symbolically and narratively and came into the conflict caused by the abstractness to the memorial landscape at Auschwitz-Birkenau ECM and Bergen-Belsen CCM. Fifth, remains for recalling the memory of tragedy and place and symbolic monuments to stand for public memory were juxtaposed at the same place and preserving on the authenticity of camp site had been conflicted with monumentalizing intentionally. Further study will required a concrete investigation of the monuments in the HCCM and an attempt to comparatively study the commemoration characteristics of memorials in Korea.

• Journal of Life Science
• /
• v.33 no.2
• /
• pp.191-198
• /
• 2023

As a member of the focal adhesion complex of the plasma membrane, Src is a nonreceptor tyrosine kinase that controls cell adhesion and motility. However, how Src activity is regulated in the plasma membrane microdomain in response to components of the extracellular matrix (ECM) remains unclear. This study compared and investigated the activity of Src in response to three representative ECM proteins: collagen type 1, fibronectin, and laminin. Genetically encoded FRET-based Src biosensors for plasma membrane subdomains were used. FRET-based biosensors allow the real-time analysis of protein activity in living cells based on their high spatiotemporal resolution. The results showed that Src activity was maintained at a high level under all ECM conditions of the lipid raft, and there was no significant difference between the ECM conditions. In contrast, Src activity was maintained at a low level in the non-lipid raft membrane. In addition, the Src activity of lipid rafts remained significantly higher than that of non-lipid raft regions under the same ECM conditions. In conclusion, this study demonstrates that Src activity can be controlled differently by lipid rafts and non-lipid raft microdomains.