• Title/Summary/Keyword: Demand Variation

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Daily influent variation for dynamic modeling of wastewater treatment plants

  • Dzubur, Alma;Serdarevic, Amra
    • Coupled systems mechanics
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    • v.9 no.2
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    • pp.111-123
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    • 2020
  • Wastewater treatment plants (WWTPs) with activated sludge system are widely used throughout the most common technologies in the world. Most treatment plants require optimization of certain treatment processes using dynamic modeling. A lot of examples of dynamic simulations require reliable data base of diurnal variation of the inflow and typical concentrations of parameters such as Chemical Oxygen Demand (COD), Total Kjeldahl Nitrogen (TKN), etc. Such detailed data are not available, which leads to problemsin the application of dynamic simulations. In many examples of plants, continuous flow measurements are only performed after the primary clarifier, whereas measurements from influent to the plant are missing, as is the case with the examples in this paper. In some cases, a simpler, faster and cheaper way can be applied to determine influent variations, such as the "HSG-Sim" method ("Hochschulgruppe Simulation"). "Hochschulgruppe Simulation" is a group of researchers from Germany, Austria, Switzerland, Luxembourg, Netherlands and Poland (see http://www.hsgsim.org). This paper presents a model for generating daily variations of inflow and concentration of municipal wastewater quality parameters, applied to several existing WWTPs in Bosnia and Herzegovina (B&H). The main goal of the applied method is to generate realistic influent data of the existing plants in B&H, in terms of flow and quality, without any prior comprehensive survey and measurements at the site. The examples of plants show the influence of overflow facilities on the dynamics of input flow and quality of wastewater, and a strong influence of the problems of the sewerage systems.

A study on the variation trends and characteristics of the adolescent girls' breast growth based on 3D body measurements - Focused on the ages from 13 to 18 - (3차원 인체 측정을 이용한 청소년기 여성의 유방 발육 변화 추이 및 특성 연구 - 만 13~18세를 중심으로 -)

  • Choi, So-Young;Chun, Jongsuk
    • The Research Journal of the Costume Culture
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    • v.22 no.6
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    • pp.943-954
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    • 2014
  • The purpose of this study was to analyze the breast growth variation trends and characteristics of Korean adolescent girls based on 3D body measurements. Subjects were 174 girls aged between 13 and 18. 3D body scanning data were collected and the data were measured by Geomagic Design X program. The total of 18 anthropometric measurements and 4 index items were analyzed. The main results of this study are as follows: 1) Overall, the breast growth of adolescent girls got out of children's body shapes at the age of 14 and the adult's body shapes appeared remarkably at the age of 18. Before the age of 15, the adolescent girls' breast enlarged. 2) The surface lengths of upper body, which means the breast volume, showed significant growth above B cup groups rather than under A cup groups. The demand of B cup size (32.2%) was higher than A cup size (25.9%). And 35.6% of subjects' brassiere band size was 70. 3) The thorax grew evenly in the circumference, depth and breadth. The thoracic development related to the breast volume as well as the whole upper body's development. These results reveal that it is necessary to develop adolescent girls' brassiere reflecting on adolescent girls' breast growth variation trends and characteristics by age, breast size and thoracic development.

Forecasting of Yeongdeok Tourist by Seasonal ARIMA Model (계절 아리마 모형을 이용한 관광객 예측 -경북 영덕지역을 대상으로-)

  • Son, Eun-Ho;Park, Duk-Byeong
    • Journal of Agricultural Extension & Community Development
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    • v.19 no.2
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    • pp.301-320
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    • 2012
  • The study uses a seasonal ARIMA model to forecast the number of tourists of Yeongdeok in an uni-variable time series. The monthly data for time series were collected ranging from 2006 to 2011 with some variation between on-season and off-season tourists in Yeongdeok county. A total of 72 observations were used for data analysis. The forecast multiplicative seasonal ARIMA(1,0,0)$(0,1,1)_{12}$ model was found the most appropriate one. Results showed that the number of tourists was 10,974 thousands in 2012 and 13,465 thousands in 2013, It was suggested that the grasping forecast model is very important in respect of how experts in tourism development in Yeongdeok county, policy makers or planners would establish strategies to allocate service in Yeongdeok tourist destination and provide tourism facilities efficiently.

Parametric study on energy demands for steel special concentrically braced frames

  • Dogru, Selcuk;Aksar, Bora;Akbas, Bulent;Shen, Jay
    • Steel and Composite Structures
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    • v.24 no.2
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    • pp.265-276
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    • 2017
  • Structures are designed in such a way that they behave in a nonlinear manner when subject to strong ground motions. Energy concepts have been widely used to evaluate the structural performance for the last few decades. Energy based design can be expressed as the balance of energy input and the energy dissipation capacity of the structure. New research is needed for multi degree of freedom systems (MDOFs)-real structures- within the framework of the energy based design methodology. In this paper, energy parameters are evaluated for low-, medium- and high-rise steel special concentrically braced frames (SCBFs) in terms of total energy input and hysteretic energy. Nonlinear dynamic time history analyses are carried out to assess the variation of energy terms along the height of the frames. A seismic energy demand spectrum is developed and hysteretic energy distributions within the frames are presented.

Output Voltage Regulation for Harmonic Compensation under Islanded Mode of Microgrid

  • Lim, Kyungbae;Choi, Jaeho
    • Journal of Power Electronics
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    • v.17 no.2
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    • pp.464-475
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    • 2017
  • This study examines a P+multi resonant-based voltage control for voltage harmonics compensation under the islanded mode of a microgrid. In islanded mode, the inverter is defined as a voltage source to supply the full local load demand without the connection to the grid. On the other hand, the output voltage waveform is distorted by the negative and zero sequence components and current harmonics due to the unbalanced and nonlinear loads. In this paper, the P+multi resonant controller is used to compensate for the voltage harmonics. The gain tuning method is assessed by the tendency analysis of the controller as the variation of gain. In addition, this study analyzes the slight voltage magnitude drop due to the practical form of the P+multi resonant and proposes a counter method to solve this problem by adding the PI-based voltage restoration method. The proposed P+multi resonant controller to compensate for the voltage harmonics is verified through the PSIM simulation and experimental results.

Color matching using dot gain and intensity compensation for different substrates (점이득 보정과 명도 보정을 이용한 서로 다른 매질 사이의 색정합)

  • 이철희;이채수;김경만;하영호
    • Journal of the Korean Institute of Telematics and Electronics S
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    • v.34S no.5
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    • pp.73-85
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    • 1997
  • In a drop-on-demand thermal ink-jet printer, the dot size of an ink droplet expelled from a printer depends on the absorption of the paper. This causes severe differences between output images on the different paper materials. In this paper, the color matching algorithm for different papers is proposed. To achieve corresponding color reproduction, dot gain compensatio nbased on saturation was applied to predict color reproduction on a printer. If the dot gain of pigment increases, the white portion of paper decreases while the saturation value increases monotonically. As the results of dot gain compensation, intensity change may appear. Therefore, an intensity compensation without any hue variation is followed to match the colors of different subtrates.

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Process Control Techniques for Quality Assurance in the Product Liability Age (PL시대에 있어서 품질보증을 위한 공정관리기법)

  • 정영배;김연수
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.20 no.42
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    • pp.73-85
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    • 1997
  • In the product liability age the demand on quality is extremely high and inspection and test are automated. The process capability indices $C_p, {\;}C_{pk}$ and p control chart widely used to provide unitless measure of process performance and process control. Traditional process capability indices $C_p, {\;}C_{pk}$ do not represent the process variation from target value. The convention p chart for control of fraction nonconforming becomes inadequate when the fraction nonconforming becomes very small such as PPM level production system. This paper proposes process performance measure considering quadratic loss function and cumulative counts control chart for control of PPM level production system.

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Yearly Variation of the Energy Use of Apartment Building (대구시 도심 공동주택의 에너지 경년 변화에 관한 연구)

  • 홍원화;이준혁
    • Journal of the Korean housing association
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    • v.13 no.2
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    • pp.1-6
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    • 2002
  • As a result of rapid economic and social change, the number of large-scale builing is expected to increase. In response to the growing increase, It will be a greater demand for up-to-date for heating and cooling, illumination, communication and disaster protection system as well as a sharp rise in overall energy consumption. Gradually the living of apartment building is increasing by growing population. In basic data will be offered for the energy conservation programs, and establishing some standards for the energy consumption in future. By understanding how energy sources are actually utilized in existing apartment houses, we can develop more appropriate strategies to maximize both the efficient use of energy and its conservation.

A Study on the RFID Tag Package Epoxy Molding through Leak Detection (기밀성 분석을 통한 RFID 태그 패키지 에폭시 몰딩 연구)

  • Ban, Chang-Woo;Hong, Seok-Kee;Jang, Dong-Young
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.21 no.2
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    • pp.297-304
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    • 2012
  • Recently RFID (Radio Frequency Identification) technology advances in wireless communication technologies are bringing new challenges. But RFID tag packaging technology has been lagging compared to the demand, so this technology is being required to improve reliability. In this paper, reliability comparison among 11 types of most commonly used epoxy molding in electrical/electronic components packaging has been made through analysis of confidentiality using a humidity sensor. Consequently, the variation of moisture penetration time causes has been verified by the changes in molding thickness for 3 types of epoxy, and from the result, the best experimental results were observed in terms of confidentiality. Moreover we have been confirmed the relationship between confidentiality, the molding thickness, and thermal property of epoxy through thermal analysis.

Optimization of base stations' configuration in UWB-based indoor localization (UWB를 이용한 실내측위의 베이스 스테이션 최적 배치)

  • Chang Ho-Wook;Cha Maeng-Q.;Kim Yong-Il;Yu Ki-Yun
    • Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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    • 2006.04a
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    • pp.3-7
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    • 2006
  • Indoor localization is getting more and more importance with the increasing demand for location based service. Location based service necessarily requires the information about customers' locations to provide them the right service according to their changing locations. To satisfy that requirement, GPS is used to achieve outdoor localization. However, there is no leading technology to achieve indoor localization. Indoor localization through UWB wave and TDOA algorithm is considered as the most accurate method until now. In implementing that method, configuration of base stations that serve as control points affects the localization accuracy. Thus, this paper discusses about optimal configuration of base stations. The variation in localization accuracy according to spatial relationship between an object and base stations Is mentioned through SEP also.

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