• Title/Summary/Keyword: REM Analysis

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Anaerobic digestion for food wastewater using HADS Pilot Plant and analysis of microbial community in the digester (HADS Pilot Plant를 이용한 음폐수의 혐기성 소화 및 미생물 군집 변화 분석)

  • Ju, Dong-Hun;Lee, Jung-Min;Park, Seong-Bum;Sung, Hyun-Je;Bae, Jae-Sang;Sang, Byoung-In
    • Journal of the Korea Organic Resources Recycling Association
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    • v.18 no.2
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    • pp.76-83
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    • 2010
  • We(Hansol EME Co. Ltd.) proceeded anaerobic digestion test for domestic food wastewater applying to two operating method for increasing of OLR. The methods are as follows. One was the rapidity operating method which was increasing the OLR continuously and rapidly and the other was the terraced operating method which was increasing the OLR having adaptation period for each step. As a result of this tests, the ratio of VFA/Alkalinity of the process was very unstable under the rapidity operating method then the volume of produced biogas was dramatically decreased. However the process was shown stable performance under the terraced operating method maintaining the ratio of VFA/Alkalinity less than 0.4. Also, the process was performing the biogas recovery of $0.8Nm^3/kgVS_{rem}/d$ and the VS removal ratio of 85%. T-RFLP analysis about the community of bacteria and methanogen is also conducted to check the change of the microbial community according to the methods of OLR increasing operation. The microbial community was changed by the methods of OLR increasing operation according to the result of T-RFLP analysis. Although the anaerobic digestion test was executed by same pilot plant, the reactivity and the tolerance of microbial community for surrounding environment could be considerably changed by the operating method for the process.

Recovering the Elevation Map by Stereo Modeling of the Aerial Image Sequence (연속 항공영상의 스테레오 모델링에 의한 지형 복원)

  • 강민석;김준식;박래홍;이쾌희
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.30B no.9
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    • pp.64-75
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    • 1993
  • This paper proposes a recovering technique of the elevation map by stereo modeling of the aerial image sequence which is transformed based on the aircraft situation. The area-based stereo matching method is simulated and the various parameters are experimentally chosen. In a depth extraction step, the depth is determined by solving the vector equation. The equation is suitable for stereo modeling of aerial images which do not satisfy the epipolar constraint. Also, the performance of the conventional feature-based matching scheme is compared. Finally, techniques analyzing the accuracy of the recovered elevation map (REM) are described. The analysis includes the error estimation for both height and contour lines, where the accuracy is based on the measurements of deviations from the estimates obtained manually. The experimental results show the efficiency of the proposed technique.

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Web services Framework for Loyal Customer Management based on RFM Models in Internet Retailing (인터넷 소매유통업의 RFM 모델 기반 충성고객관리를 위한 웹서비스(WsLCM) 프레임웍)

    • Journal of Intelligence and Information Systems
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    • v.8 no.1
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    • pp.41-41
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    • 2002
  • 소매유통업에 있어 충성고객을 발견하고 효과적으로 관리하는 일은 마케팅 부서의 주요 관심사라고 할 수 있다. 최근 성숙된 유통 채널로 자리잡고 있는 인터넷 소매유통업도 다양한 마케팅 노력을 기울이고 있으며 그 성과가 기존 소매유통업 보다 클 것으로 기대하고 있는데 이는 인터넷 소매유통업이 기본적으로 디지털 기반 구조 하에 사업이 수행되기 때문이다. 그러나, 매출 규모가 확장됨에 따라 고객 관계가 보다 복잡해지고 거래 건수도 크게 확장되고 있는 인터넷 소매유통업은 전자적으로 이용 가능한 고객 관리 서비스를 필요로 하고 있다 본 논문은 인터넷 소매유통업의 충성고객관리를 위한 웹서비스의 프레임웍 및 적용 사례를 제시하고 있다. 고객관리 웹서비스의 기본 모델은 전통적인 RFM분석에 기반을 두고 있는데 복잡한 충성고객관리 업무를 처리하는 에이전트를 제공한다. 인터넷 쇼핑몰이나 상점의 운영 시스템과 용이하게 통합될 수 있는 웹서비스는 적은 비용으로 효과적인 고객관리를 실현하는데 기여할 것으로 기대된다.

A Study on the Concept and Spatial Organization of Bifurcation (분기(Bifurcation)의 개념과 공간조직에 관한 연구)

  • Kim Jong-Jin
    • Korean Institute of Interior Design Journal
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    • v.14 no.1
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    • pp.20-27
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    • 2005
  • This study is focused on the concept and spatial organization of bifurcation. After discussing the concept of bifurcation used in Borges' literature and Deleuze's Fold philosophy, case examples in contemporary architecture are analysed to comparatively investigate the relationship between the concept and space. In Deleuze's philosophy, bifurcation as well as pleats, inflection are used to form the world of fold that goes to infinity while, in Borges' literature, the structure of bifurcation is the key method to create the labyrinth of time. There are various projects in contemporary architecture based on the Deleuzian concept of bifurcation. Rem Koolhaas's Two Libraries for Jussieu University and UN Studio's Arnhem Central are selected and researched for further comparison study. In Jussieu project, the bifurcating spatial organization is 'intentionally' used to construct the indeterminant space whereas in Arnhem Central, bifurcation can be found in both the ever-bifurcating design process as well as the final spatial organization'unintentionally'generated from the process. This study is concluded with the comparative analysis between the representation and actualization of a concept that are crucially different.

Volume Reduction of Waste Water Sludge using Electrolysis (전기분해를 이용한 하수 슬러지 감량)

  • Lee, Byungheon;Bang, Myunghwan;Kim, Geonha
    • Journal of Korean Society on Water Environment
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    • v.22 no.2
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    • pp.264-270
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    • 2006
  • In this research, volume reduction of activated sludge using electrolysis was studied to find an optimum condition using lab scale experiments. Wasted sludge was treated by electrolysis with controlling current density, chloride concentration, electrode distance, and reaction time. Volume of return sludge was reduced by 9.79% in average while maximum was 16.7%. Sludge volume reduction efficiency was affected by current density and reaction time. It was reversely proportional to the electrode distance. Especially current density was effective on the system performance significantly. Electric conductivity, salinity and COD were increased by electrolysis implying sludge disintegrated and converted to COD in part. An empirical equation for total solid removal efficiency by electrolysis was proposed by multiple linear regression analysis as: $TS_{rem}$(%) = 5.534 ${\times}$ current density (A/l) + 0.178 ${\times}$ reaction time (m) + 2.758.

A Root Fillet Stress Calculation Method for Thin-Rimmed spur Gears (얇은 림 평치차의 이뿌리 응력 계산법)

  • Chong, Tae-Hyong;Choi, Jae-Hoon
    • Journal of the Korean Society for Precision Engineering
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    • v.8 no.2
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    • pp.89-105
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    • 1991
  • A method to apply the approximation formulae[1] for tooth fillet and root stresses of a thin-rimmed rack to the calculation of stress state of thin-rimmed external and internal spur gears is introduced. The stress values by the method proposed in this paper have shown good agreement with those by the REM analysis and also by the stress measurement of strain survey investigation. By this method, reliable stress state at tooth fillet and root areas in the thin-rimmed external and internal spur gears can be easily calculated, and a practical design method for the bending strength of such thin-rimmed gears is established.

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Determinants of Economic Growth in ASEAN Countries (2002-2019)

  • Khin Theingi Aung
    • SUVANNABHUMI
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    • v.15 no.2
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    • pp.215-244
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    • 2023
  • This study analyzes the effect of macroeconomic indicators such as foreign direct investment (FDI), domestic investment, trade, inflation, unemployment, population, and governance indicators on economic growth and points out the GDP growth rate in 2002- 2019 among ASEAN countries. Data were compiled from the Worldwide Governance Indicators (WGI) and the World Bank, and the effect of variables on GDP was predicted using the pooled ordinary least squares (POLS), fixed effects model (FEM), and random effects model (REM) methods. As a measure of growth, the GDP growth rate has been taken; FDI and domestic investment, trade, inflation, and governance indicators are positively connected and have an influence on economic growth in these ASEAN countries; domestic investment, population, and unemployment have a negative relationship to economic growth. The macroeconomic indicators and institutional stability of the nation have an effect on its economic growth. Comprehensive institutional stability and well-laid macroeconomic policies are required for growth to materialize.

Analysis of Physical Characteristics of Sound Environment and the Subjective Reactions in Hanok Complexes (한옥주거단지 소리환경의 물리적 특성과 주관반응의 관계 분석)

  • Shin, Yong-Gyu;Park, Hyeon-Ku;Kook, Chan;Kim, Sun-Woo
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.24 no.2
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    • pp.154-161
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    • 2014
  • Demands for Korean Traditional Residence Complexes as a more humane resident space have recently been increasing for the purposes of users' health and convenience, built with the purpose of reflecting various trends. This study is aimed at examining the physical characteristics of design in residence complexes by analyzing the physical characteristics of the sound environment as auditory elements of Hanok Complexes and the relationship between spatial and visual test values. The results were shown as follows: In subjective evaluation at Hanok, Natural sounds were recognized higher but artificial sounds were lower. According to the interrelationship analysis between subjective evaluation and physical measurement values, entrance (regular-StdDev), yard (regular-NbEm, friendly-G), waterside (regular-articulation index(rooms), StdDev, $L_{min}$, Rem), etc had been shown highly related.

Factors Affecting the Implementation of Environmental Accounting by Construction Companies Listed on the Ho Chi Minh Stock Exchange

  • NGUYEN, Thi Mai Huong;NGUYEN, Thi Kim Tuyen;NGUYEN, Thi Thao Vi
    • The Journal of Asian Finance, Economics and Business
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    • v.7 no.8
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    • pp.269-280
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    • 2020
  • The study investigates Environmental Accounting Information (EAI) as well as factors affecting the environmental accounting implementation by the construction firms listed on the Ho Chi Minh Stock Exchange (HOSE), Vietnam. After eliminating seven enterprises that lacked data, the authors selected a sample of 112 observations from 28 construction businesses listed on the Ho Chi Minh Stock Exchange in the period 2015-2018. This study uses research data extracted from the companies' annual reports. Then, the data are analyzed by Stata 13 software, including descriptive statistics, correlation coefficient analysis, regression analysis of table data using estimation methods (Pooled OLS, REM, FEM), and testing of model defects (heteroskedasticity test, multicollinearity test, autocorrelation test). The results show that construction companies listed on the Ho Chi Minh Stock Exchange have out factors affecting the environmental accounting implementation by these enterprises, including independent audit firm and listed time. While the independent auditor firm has a positive and significant impact, the listed time has a negative influence. In addition, our study has confirmed the role of institutional factors affecting the disclosure level of EAI on the implementation of environmental accounting by construction enterprises listed on the Ho Chi Minh Stock Exchange.

Fourier and Wavelet Analysis for Detection of Sleep Stage EEG (수면단계 뇌파 검출을 위한 Fourier 와 Wavelet해석)

  • Seo Hee-Don;Kim Min-Soo
    • Journal of Biomedical Engineering Research
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    • v.24 no.6 s.81
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    • pp.487-494
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    • 2003
  • The sleep stages provides the most basic evidence for diagnosing a variety of sleep diseases. for staging sleep by analysis of EEG(electroencephalogram), it is especially important to detect the characteristic waveforms from EEG. In this paper, sleep EEG signals were analyzed using Fourier transform and continuous wavelet transform as well as discrete wavelet transform. Proposeed system methods. Fourier and wavelet for detecting of important characteristic waves(hump, sleep spindles. K-complex, hill wave, ripple wave) in sleep EEG. Sleep EEG data were analysed using Daubechies wavelet transform method and FFT method. As a result of simulation, we suggest that our neural network system attain high performance in classification of characteristic waves.