• Title/Summary/Keyword: Disaggregation

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Climate Change effect on Rainfall Frequency analysis using high resolution RCM Data (고해상도의 RCM 자료를 이용한 기후변화가 강우빈도 분석에 미치는 영향)

  • Kim, Byung-Sik;Kim, Bo-Kyung;Kwon, Hyun-Ha;Yoon, Seok-Young
    • Proceedings of the Korea Water Resources Association Conference
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    • 2008.05a
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    • pp.224-228
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    • 2008
  • 2007년 세계경제포럼(WEF)은 우리가 직면한 최우선 해결과제로 기후변화를 언급하였다. 최저 기온 상승과 가뭄 영향 지역 확대, 폭염일수와 지역적 홍수 위험 증가 등 각종 이상기상이 야기하는 피해 확대에 대한 예상과 우려 때문이다(IPCC, 2007). 세계적으로 고온극한과 호우빈도 증가, 태풍 세기가 강화될 것으로 전망되고 있으며(IPCC, 2007), 국내의 경우 겨울철 한파 감소와 대설 피해 증가, 여름철 집중호우의 강도 심화, 가을철 초대형 태풍 발생으로 인한 피해 가능성이 예측 되고 있다(기상연구소, 2007). 현재, 이러한 현상들을 가시화하고 대처방안을 마련하기 위한 일환으로 기후변화 시나리오(GCM)가 작성되어 연구에 이용되고 있다. 그러나 GCM의 경우, 공간적 해상도가 낮아 지형학적 특성 등을 충분히 반영하지 못하는 단점이 있어 최근에는 공간 해상도가 GCM보다 높은 RCM(Regional Climate Model, 지역기후모델)자료를 적용한 연구도 진행되고 있다. 본 논문에서는 SRES A2 온난화가스시나리오 기반의 기상청 RegCM3 RCM($27km{\times}27km$)로 부터 일(daily)단위 자료를 각각 모의하여 비교하고, BLRPM을 이용하여 일(daily)단위 자료를 시(hourly)단위로 분해(disaggregation)하였다. 그리고 이들을 이용하여 지속기간별 확률강우량을 산정하여 미래 기후변화가 극한 강우에 미치는 영향을 평가하였다.

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Conditional mean spectrum for Bucharest

  • Vacareanu, Radu;Iancovici, Mihail;Pavel, Florin
    • Earthquakes and Structures
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    • v.7 no.2
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    • pp.141-157
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    • 2014
  • The Conditional Mean Spectrum represents a powerful link between the seismic hazard information and the selection of strong ground motion records at a particular site. The scope of the paper is to apply for the city of Bucharest for the first time the method to obtain the Conditional Mean Spectrum (CMS) presented by Baker (2011) and to select, on the basis of the CMS, a suite of strong ground motions for performing elastic and inelastic dynamic analyses of buildings and structures with fundamental periods of vibration in the vicinity of 1.0 s. The major seismic hazard for Bucharest and for most of Southern and Eastern Romania is dominated by the Vrancea subcrustal seismic source. The ground motion prediction equation developed for subduction-type earthquakes and soil conditions by Youngs et al. (1997) is used for the computation of the Uniform Hazard Spectrum (UHS) and the CMS. The disaggregation of seismic hazard is then performed in order to determine the mean causal values of magnitude and source-to-site distance for a particular spectral ordinate (for a spectral period T = 1.0 s in this study). The spectral period of 1.0 s is considered to be representative for the new stock of residential and office reinforced concrete (RC) buildings in Bucharest. The differences between the Uniform Hazard Spectrum (UHS) and the Conditional Mean Spectrum (CMS) are discussed taking into account the scarcity of ground motions recorded in the region of Bucharest and the frequency content characteristics of the recorded data. Moreover, a record selection based on the criteria proposed by Baker and Cornell (2006) and Baker (2011) is performed using a dataset consisting of strong ground motions recorded during seven Vrancea seismic events.

Polyphenolic Biflavonoids Inhibit Amyloid-Beta Fibrillation and Disaggregate Preformed Amyloid-Beta Fibrils

  • Choi, Erika Y.;Kang, Sam Sik;Lee, Sang Kook;Han, Byung Hee
    • Biomolecules & Therapeutics
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    • v.28 no.2
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    • pp.145-151
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    • 2020
  • Alzheimer's disease (AD) is a devastating neurodegenerative disease and a major cause of dementia in elderly individuals worldwide. Increased deposition of insoluble amyloid β (Aβ) fibrils in the brain is thought be a key neuropathological hallmark of AD. Many recent studies show that natural products such as polyphenolic flavonoids inhibit the formation of insoluble Aβ fibrils and/or destabilize β-sheet-rich Aβ fibrils to form non-cytotoxic aggregates. In the present study, we explored the structure-activity relationship of naturally-occurring biflavonoids on Aβ amyloidogenesis utilizing an in vitro thioflavin T assay with Aβ1-42 peptide which is prone to aggregate more rapidly to fibrils than Aβ1-40 peptide. Among the biflavonoids we tested, we found amentoflavone revealed the most potent effects on inhibiting Aβ1-42 fibrillization (IC50: 0.26 µM), as well as on disassembling preformed Aβ1-42 fibrils (EC50: 0.59 µM). Our structure-activity relationship study suggests that the hydroxyl groups of biflavonoid compounds play an essential role in their molecular interaction with the dynamic process of Aβ1-42 fibrillization. Our atomic force microscopic imaging analysis demonstrates that amentoflavone directly disrupts the fibrillar structure of preformed Aβ1-42 fibrils, resulting in conversion of those fibrils to amorphous Aβ1-42 aggregates. These results indicate that amentoflavone affords the most potent anti-amyloidogenic effects on both inhibition of Aβ1-42 fibrillization and disaggregation of preformed mature Aβ1-42 fibrils.

Assessment of Frequency Analysis using Daily Rainfall Data of HadGEM3-RA Climate Model (HadGEM3-RA 기후모델 일강우자료를 이용한 빈도해석 성능 평가)

  • Kim, Sunghun;Kim, Hanbeen;Jung, Younghun;Heo, Jun-Haeng
    • Journal of Wetlands Research
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    • v.21 no.spc
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    • pp.51-60
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    • 2019
  • In this study, we performed At-site Frequency Analysis(AFA) and Regional Frequency Analysis(RFA) using the observed and climate change scenario data, and the relative root mean squared error(RMMSE) was compared and analyzed for both approaches through Monte Carlo simulation. To evaluate the rainfall quantile, the daily rainfall data were extracted for 615 points in Korea from HadGEM3-RA(12.5km) climate model data, one of the RCM(Regional Climate Model) data provided by the Korea Meteorological Administration(KMA). Quantile mapping(QM) and inverse distance squared methods(IDSM) were applied for bias correction and spatial disaggregation. As a result, it is shown that the RFA estimates more accurate rainfall quantile than AFA, and it is expected that the RFA could be reasonable when estimating the rainfall quantile based on climate change scenarios.

Spectogram analysis of active power of appliances and LSTM-based Energy Disaggregation (다수 가전기기 유효전력의 스팩토그램 분석 및 LSTM기반의 전력 분해 알고리즘)

  • Kim, Imgyu;Kim, Hyuncheol;Kim, Seung Yun;Shin, Sangyong
    • Journal of the Korea Convergence Society
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    • v.12 no.2
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    • pp.21-28
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    • 2021
  • In this study, we propose a deep learning-based NILM technique using actual measured power data for 5 kinds of home appliances and verify its effectiveness. For about 3 weeks, the active power of the central power measuring device and five kinds of home appliances (refrigerator, induction, TV, washing machine, air cleaner) was individually measured. The preprocessing method of the measured data was introduced, and characteristics of each household appliance were analyzed through spectogram analysis. The characteristics of each household appliance are organized into a learning data set. All the power data measured by the central power measuring device and 5 kinds of home appliances were time-series mapping, and training was performed using a LSTM neural network, which is excellent for time series data prediction. An algorithm that can disaggregate five types of energies using only the power data of the main central power measuring device is proposed.

Optical Detection of Red Blood Cell Aggregation under vibration (진동장에서의 적혈구 응집성을 측정하는 광학적 방법)

  • Jang, Ju-Hee;Park, Myung-Su;Ku, Yun-Hee;Shin, Se-Hyun
    • Proceedings of the KSME Conference
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    • 2004.11a
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    • pp.1510-1515
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    • 2004
  • Aggregability of red blood cells (RBCs) was determined by a laser backscattering light analysis in a microfluidic channel. Available techniques for RBC aggregation often adopt a rotational Couette-flow using bob-and-cup system for disaggregating RBCs, which causes the system to be complex and expensive. A disposable microfluidic channel and vibration generating mechanism were used in the proposed new detection system for RBC aggregation. Prior to measurement, RBC aggregates in a blood sample were completely disaggregated by applying vibration-induced shear. With the present apparatus, the aggregation indexes of RBCs can be easily measured with small quantities of blood sample. The measurements with the present aggregometer were compared with those of LORCA and showed a strong correlation between them. The aggregability of the defibrinogenated blood RBCs is markedly lower than that of the normal RBCs. The noble feature of this design is the vibration-induced disaggregation mechanism, which enables to incorporate disposable element that holds the blood sample.

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Implementation of Light-weight I/O Stack for NVMe-over-Fabrics

  • Ahn, Sungyong
    • International journal of advanced smart convergence
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    • v.9 no.3
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    • pp.253-259
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    • 2020
  • Most of today's large-scale cloud systems and enterprise data centers are distributing resources to improve scalability and resource utilization. NVMe-over-Fabric protocol allows submitting NVMe commands to a remote NVMe SSD through RDMA (Remote Direct Memory Access) network. It is attracting attention recently because it is possible to construct a disaggregation storage system with low latency through the protocol. However, the current I/O stack of NVMe-over-Fabric has an inefficient structure for maintaining compatibility with the traditional I/O stack. Therefore, in this paper, we propose a new mechanism to reduce I/O latency and CPU overhead by modifying I/O path of NVMe-over-Fabric to pass through legacy block layer. According to the performance evaluation results, the proposed mechanism is able to reduce the I/O latency and CPU overhead by up to 22% and 24% compared to the existing NVMe-over-Fabrics protocol, respectively.

Preliminary Study on Appliance Load Disaggregation Using Dynamic Time Warping Method (Dynamic Time Warping(DTW)기법을 이용한 가전기기별 부하 패턴 분류 기초연구)

  • Jang, Minseok;Kong, Seongbae;Ko, Rakkyung;Chong, Ju Young;Joo, Sung-Kwan
    • Proceedings of the KIEE Conference
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    • 2015.07a
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    • pp.45-46
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    • 2015
  • 가전기기별 에너지 사용정보를 제공함으로써 가정에서 효율적인 에너지 사용을 유도할 수 있다. 가전기기별 사용정보를 효과적으로 제공하기 위해서는 NILM (Non-Intrusive Load Monitoring) 기법이 필요하다.본 논문에서는 개별 가전기기 분류단계에서 쓰이는 DTW(Dynamic Time Warping) 기법을 소개한다. DTW 기법은 다른 두 시계열 데이턴간의 유사도를 측정하는 패턴인식 기법 중 하나이다. 이 유사도를 이용하여 가전기기의 동작여부를 판별하고 분류를 수행한다.

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Bioinformatics Analysis of Hsp20 Sequences in Proteobacteria

  • Heine, Michelle;Chandra, Sathees B.C.
    • Genomics & Informatics
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    • v.7 no.1
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    • pp.26-31
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    • 2009
  • Heat shock proteins are a class of molecular chaperones that can be found in nearly all organisms from Bacteria, Archaea and Eukarya domains. Heat shock proteins experience increased transcription during periods of heat induced osmotic stress and are involved in protein disaggregation and refolding as part of a cell's danger signaling cascade. Heat shock protein, Hsp20 is a small molecular chaperone that is approximately 20kDa in weight and is hypothesized to prevent aggregation and denaturation. Hsp20 can be found in several strains of Proteobacteria, which comprises the largest phyla of the Bacteria domain and also contains several medically significant bacterial strains. Genomic analyses were performed to determine a common evolutionary pattern among Hsp20 sequences in Proteobacteria. It was found that Hsp20 shared a common ancestor within and among the five subclasses of Proteobacteria. This is readily apparent from the amount of sequence similarities within and between Hsp20 protein sequences as well as phylogenetic analysis of sequences from proteobacterial and non-proteobacterial species.

Effect of Acetophenone on the Rate of Wool Dyeing (아세토페논이 양모의 염색속도에 미치는 영향)

  • Dho, Seong-Kook
    • Fashion & Textile Research Journal
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    • v.10 no.3
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    • pp.394-398
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    • 2008
  • One of barely water soluble ketones, acetophenone (AP) was dissolved in methanol and then was mixed with aqueous solution of C. I. Red Acid 114. In order to find out the role of AP in the dyeing process the rate constants and the activation parameters were calculated. The rate for the dyeing with AP was faster than that without it. Because of the reduced temperature dependence by AP the activation energy ($E_a$) for the dyeing with AP was smaller than that without it. With increasing temperature the activation enthalpy (${\Delta}H^*$), the activation entropy (${\Delta}S^*$), and the activation free energy ($G^*$) decreased, which was more noticeable in dyeing with AP. The rate constants and the activation parameters agreed well with the results from the previous reports that the ability of AP to increase disaggregation of dye molecules, loosening the wool fiber, and wickabilty of dyeing solution made it possible to dye wool fiber at low temperature.