• Title/Summary/Keyword: Data Envelope Analysis

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Percentile Envelope and Its Characteristic of Error Distribution for Supernormality

  • Lee, Jea-Young;Rhee, Seong-Won
    • Journal of the Korean Data and Information Science Society
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    • v.12 no.2
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    • pp.35-45
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    • 2001
  • We introduce a new percentile envelope for diagnosing supernormality in regression analysis. Furthermore, we compare this percentile envelope, which is much simpler and easier, with Atkinson's and Flack and Flores' envelopes. Using percentile envelope, we investigate characteristics of normal probability plots with envelope for error distributions when supernormality is occurred. We give cautions that test result for normality assumption of errors can be reached the wrong conclusion by supernormality.

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Spatial Complex Envelope of Acoustic Field : Its Definition and Characteristics (음장의 공간 복소 포락: 정의와 특성)

  • Park, Choon-Su;Kim, Yang-Hann
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.17 no.8
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    • pp.693-700
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    • 2007
  • We can predict spatial acoustic pressure distribution on the plane of interest by using acoustic holography. However, the information embedded in the distribution plot is usually much more than what we need: for example, source locations and their overall propagation pattern. One possible candidate to solve the problem is complex envelope analysis. Complex envelope analysis extracts slowly-varying envelope signal from a band signal. We have attempted to extend this method to space domain so that we can have spatial information that we need. We have to modulate two dimensional data for obtaining spatial envelope. Although spatial modulation basically follows the same concept that is used in time domain, the algorithm for the spatial modulation turns out to be different from temporal modulation. We briefly describe temporal complex envelope analysis and extend it to spatial envelope of 2-D acoustic field by introducing geometric transformation. In the end, the results of applying the spatial envelope to the holography are envisaged and verified.

An Analysis of the Environment-Friendly Envelop Show in European Urban Housing (유럽의 집합주택에서 나타나는 환경친화적인 외피구성기법 분석)

  • Lee, Chung-Mi;Oh, Se-Gyu
    • Proceeding of Spring/Autumn Annual Conference of KHA
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    • 2005.11a
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    • pp.279-282
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    • 2005
  • As cognizance of necessity of environmentally friendly building is growing, techniques to construct environmentally friendly envelope of contemporary architecture is being changed and developed. Though the stream of times likes this, applications of those are focused on office buildings but rarely on residential projects. A begin of this study is to address analysis of environmentally friendly envelope techniques in urban housing in Europe constructed after 1995 which is the very time that the notion of ecological architecture. The result of this analysis should be a suggestion of radical data to make buildings be more buildings be more environmentally friendly and having amenities.

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An Analysis of Façade Panel Characteristics of UN Studio's Office Projects (유엔스튜디오 업무시설 외피 패널의 형태적 특성 분석)

  • Ko, Sung Hak
    • Journal of the Architectural Institute of Korea Planning & Design
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    • v.35 no.8
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    • pp.23-34
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    • 2019
  • The façade, a fundamental function as a skin that protects human life from external environment such as cold and hot weather, snow, rain, and wind, etc, has served as a media for communication between indoor space of the building and outside space. From the media for communication point of view, the approach to envelope design, in which environmental elements are transmitted internally through the filtering of external environments, has been evolving in various ways from the past to the present. Today, modern architecture technologies including curtain wall systems and user-friendly computer programming and environmental analysis programs demonstrate a differentiated approach to envelope design related to the indoor environment. For this reason, it is worth noting that the envelope design factors and trends that appear variously in the UNStudio's projects before and after the 2000s. The factors reflected in the envelop design in conjunction with the indoor environment obtained through the case study of the UNStudio's office projects were daylight environment, thermal environment, ventilation, noise, privacy and view, and consideration for daylight environment and thermal environment was reflected in many cases through the case study. Looking at the changes in the diagrams in order of year, it can be seen that the envelope design using the environmental analysis tool has been performed since 2006. This is a clue to show the envelop design changes from the conceptual method to the data-based one. The diagrams and analysis results related to the envelop design showed that the thermal environment related to solar radiation was the most, and no diagrams and analysis related to the indoor illumination were found. Since 2010, PV panel installation has been shown in the envelope design, which can be found in the increased efficiency of PV panels due to the technological advances and the decrease in production cost.

A qualitative evaluation method for engine and its operating-envelope using GSP (Gas turbine Simulation Program)

  • Kyung, Kyu-Hyung;Jun, Yong-Min;Yang, Soo-Seok;Choi, Dong-Whan
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2004.03a
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    • pp.848-853
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    • 2004
  • Regarding to the project SUAV (Smart Unmanned Aerial Vehicle) in KARI (Korea Aerospace Research Institute), several engine configurations has been evaluated. However it's not an easy task to collect all the necessary data of each engine for the analysis. Usually, some kind of modeling technique is required in order to determine the unknown data. In the present paper a qualitative method for reverse engineering is proposed, in order to identify some design patterns and relationships between parameters. The method can be used to estimate several parameters that usually are not provided by the manufacturer. The method consists of modeling an existing engine and through a simulation, compare its transient behavior with its operating envelope. In the simulation several parameters such as thermodynamics, performance, safety and mechanics concerning to the definition of operation-envelope, have been discussed qualitatively. With the model, all engine parameters can be estimated with acceptable accuracy, making possible the study of dependencies among different parameters such as power-turbine total inertia, TIT, take-off time and part load, in order to check if the engine transient performance is within the design criteria. For more realistic approach and more detailed design requirements, it will be necessary to enhance the compressor map first, and more realistic estimated values must be taken into account for intake-loss, bleed-air and auxiliary power extraction. The relative importance of these “unknown” parameters must be evaluated using sensitivity analysis in the future evaluation. Moreover, fluid dynamics, thermal analysis and stress analysis necessary for the resulting life assessment of en engine, will not be addressed here but in a future paper. With the methodology presented in the paper was possible to infer the relationships between operation-envelope and engine parameters.

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Analysis of Natural Recombination in Porcine Endogenous Retrovirus Envelope Genes

  • Lee, Dong-Hee;Lee, Jung-Eun;Park, Nu-Ri;Oh, Yu-Kyung;Kwon, Moo-Sik;Kim, Young-Bong
    • Journal of Microbiology and Biotechnology
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    • v.18 no.3
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    • pp.585-590
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    • 2008
  • Human tropic Porcine Endogenous Retroviruses (PERVs) are the major concern in zoonosis for xenotransplantation because PERVs cannot be eliminated by specific pathogen-free breeding. Recently, a PERV A/C recombinant with PERV-C bearing PERV-A gp70 showed a higher infectivity (approximately 500-fold) to human cells than PERV-A. Additionally, the chance of recombination between PERVs and HERVs is frequently stated as another risk of xenografting. Overcoming zoonotic barriers in xenotransplantation is more complicated by recombination. To achieve successful xenotransplantation, studies on the recombination in PERVs are important. Here, we cloned and sequenced proviral PERV env sequences from pig gDNAs to analyze natural recombination. The envelope is the most important element in retroviruses as a pivotal determinant of host tropisms. As a result, a total of 164 PERV envelope genes were cloned from pigs (four conventional pigs and two miniature pigs). Distribution analysis and recombination analysis of PERVs were performed. Among them, five A/B recombinant clones were identified. Based on our analysis, we determined the minimum natural recombination frequency among PERVs to be 3%. Although a functional recombinant envelope clone was not found, our data evidently show that the recombination event among PERVs may occur naturally in pigs with a rather high possibility.

Application of Artificial Neural Network for Optimum Controls of Windows and Heating Systems of Double-Skinned Buildings (이중외피 건물의 개구부 및 난방설비 제어를 위한 인공지능망의 적용)

  • Moon, Jin-Woo;Kim, Sang-Min;Kim, Soo-Young
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.24 no.8
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    • pp.627-635
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    • 2012
  • This study aims at developing an artificial neural network(ANN)-based predictive and adaptive temperature control method to control the openings at internal and external skins, and heating systems used in a building with double skin envelope. Based on the predicted indoor temperature, the control logic determined opening conditions of air inlets and outlets, and the operation of the heating systems. The optimization process of the initial ANN model was conducted to determine the optimal structure and learning methods followed by the performance tests by the comparison with the actual data measured from the existing double skin envelope. The analysis proved the prediction accuracy and the adaptability of the ANN model in terms of Root Mean Square and Mean Square Errors. The analysis results implied that the proposed ANN-based temperature control logic had potentials to be applied for the temperature control in the double skin envelope buildings.

Extracting Seismic Reinforcement Priorities to Promote Safety at Airmen Dormitories Using DEA (DEA 기법을 이용한 공군 병영생활관 내진보강 우선순위 도출)

  • Park, Keunwoo
    • Journal of the Korea Institute of Military Science and Technology
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    • v.22 no.5
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    • pp.697-704
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    • 2019
  • The public has grown more anxious towards domestic earthquakes that have been taking place since 2000, and regulations on seismic design has been strengthened. Out of 4,605 Air Force installations that require the application of seismic design, 2,982 remain unapplied. By taking budget issues and the time spent to implement seismic retrofit into account, this paper aims to list up seismic reinforcement priorities for airmen dormitories where they can potentially be most vulnerable to earthquakes. The priorities are extracted based on Data Envelope Analysis(DEA). To apply DEA, two sets of variables are set: seismic reinforcement costs as input variable: age of building, number of residents, and seismic load as output variables. At the end, suggestions are made for developing seismic reinforcement plans that can be applied to all Air Force installations.

Stability Analysis Using the Amplitude Envelope of Dynamic Pressure in the Rocket Combustor (로켓 연소기의 동압 진폭엔벨롭을 이용한 안정성 해석)

  • Lee, Soo Yong
    • Journal of the Korean Society of Propulsion Engineers
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    • v.25 no.1
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    • pp.42-49
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    • 2021
  • As a measure of susceptibility on the combustion instability, thermo-acoustic instabilities in rocket combustion system was considered for the estimation of the operational stability margin. Growth rate, which governs the asymptotic stability behavior of the system, was determined from the dynamic data measured during combustion tests in order to understand the dynamic characteristics of combustor system. Frequency transform technique was first applied to determine the system parameters such as growth rate and/or damping coefficient for an interested mode from the time series pressure data, and the PDFs of pressure amplitude were extracted from the amplitude envelope of pressure oscillation for the stochastic analysis.

Study on Energy Consumption according to Building Envelope Performance and Indoor Temperature (건축물의 외피성능 및 실내온도에 따른 에너지 사용량에 관한 연구)

  • Yoo, Ho-Chun;Kang, Hyun-Gu
    • Journal of the Korean Solar Energy Society
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    • v.31 no.3
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    • pp.101-108
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    • 2011
  • This study aims to suggest an energy consumption improvement plan for university buildings through an analysis of energy consumption. Upon a simulation of subject building to interpret energy consumption, it was found that 154.07kWh/$m^2$ of energy is consumpted annually. Improvement of design elements can cut down the energy consumption to 135.61kWh/$m^2$ according to an energy reduction analysis related to envelope performance improvement. Additional improvement of lights and heat exchanger can curtail annual energy consumption to 108.32kWh/$m^2$. Also, an analysis of energy consumption while increasing indoor temperature gradually showed that the two factors are in proportion. $6^{\circ}C$ higher temperature requires over twice of the current energy. Based on this survey result, performance improvement due to building management and envelope elements which influence to building cooling and heating loads can curtail building energy consumption.