• Title/Summary/Keyword: Environmental parameters

Search Result 5,072, Processing Time 0.04 seconds

Kindergarten space design based on BP (back propagation) neural network (BP 신경 망 기반 유치원 공간 설계)

  • Liao, PengCheng;Pan, Younghwan
    • Journal of the Korea Convergence Society
    • /
    • v.12 no.9
    • /
    • pp.1-10
    • /
    • 2021
  • In the past, designers relied primarily on past experience and reference to industry standard thresholds to design spaces. Such design often results in spaces that do not meet the needs of users. The purpose of this paper is to investigate the process and way of generating design parameters by constructing a BP neural network algorithm for spatial design. From the perspective. This paper adopts an experimental research method to take a kindergarten with a large number of complex needs in space as the object of study, and through the BP neural network algorithm in machine learning, the correlation between environmental behavior parameters and spatial design parameters is imprinted. The way of generating spatial design parameters is studied. In the future, the corresponding spatial design parameters can be derived by replacing specific environmental behavior influence factors, which can be applied to a wider range of scenarios and improve the efficiency of designers.

Statistical Analysis of Sewage Plant Operation (하수처리장 운전조건의 통계분석)

  • 이찬형;문경숙
    • Journal of Environmental Science International
    • /
    • v.11 no.1
    • /
    • pp.63-68
    • /
    • 2002
  • In this study, we examined statistical analysis between sewage plant operations parameters and effluent quality We got six components from principle component analysis of the operation parameters and secondary effluent quality. 91.8% of the total variance was explained by the six components. The components were identified in the following order : 1) organic matter removal by aeration basin microbe, 2) settleability on secondary clarifier load, 3) removal of nutrients, 4) microbial number increasement and species diversity, 5) microbial activity in aeration basin, 6) oxidation in aeration basin.

Control of Automated Greenhouse Based on a PC (PC 기반 자동화 시설 하우스 제어)

  • 김기환
    • The Transactions of the Korean Institute of Electrical Engineers D
    • /
    • v.53 no.9
    • /
    • pp.644-649
    • /
    • 2004
  • To control a greenhouse is to control environmental parameters in greenhouse. Controlled environments may be as simple as saran-covered shade houses or as complex as growth chambers. Although greenhouses are probably the most common example of a controlled environment used in agricultural/horticultural production, the type of controlled environment or system that is needed depends upon the climate, time of year, crops being produced and the environmental parameters that must be controlled. In this contribution puts emphasis on construction of automatic-controlled greenhouse system by personal computer.

A Review of Ocean Wave Power Extraction; the primary interface

  • Nik, W.B. Wan;Muzathik, A.M.;Samo, K.B.;Ibrahim, M.Z.
    • International Journal of Fluid Machinery and Systems
    • /
    • v.2 no.2
    • /
    • pp.156-164
    • /
    • 2009
  • This paper aims to describe the importance of data, data collection methods, parameters to estimate the potential of wave energy and environmental impacts. The technical and economical status in wave energy conversion is outlined. Power and energy efficiency relationships are discussed. Many different types of wave-energy converters have been detailed. The progress in wave energy conversion in Malaysia is reviewed.

Comparative Study of Mass Transfer and Bubble Hydrodynamic Parameters in Bubble Column Reactor: Physical Configurations and Operating Conditions

  • Sastaravet, Prajak;Chuenchaem, Chomthisa;Thaphet, Nawaporn;Chawaloesphonsiya, Nattawin;Painmanakul, Pisut
    • Environmental Engineering Research
    • /
    • v.19 no.4
    • /
    • pp.345-354
    • /
    • 2014
  • In this paper, effects of physical configurations and operating conditions on bubble column performance were analyzed in terms of bubble hydrodynamic and mass transfer parameters. Bubble column with 3 different dimensions and 7 gas diffusers (single / multiple orifice and rigid / flexible orifice) were applied. High speed camera and image analysis program were used for analyzing the bubble hydrodynamic parameters. The local liquid-side mass transfer coefficient ($k_L$) was estimated from the volumetric mass transfer coefficient ($k_La$) and the interfacial area (a), which was deduced from the bubble diameter ($D_B$) and the terminal bubble rising velocity ($U_B$). The result showed that the values of kLa and a increased with the superficial gas velocity (Vg) and the size of bubble column. Influences of gas diffuser physical property (orifice size, thickness and orifice number) can be proven on the generated bubble size and the mass transfer performance in bubble column. Concerning the variation of $k_L$ coefficients with bubble size, 3 zones (Zone A, B and C) can be observed. For Zone A and Zone C, a good agreement between the experimental and the predicted $K_L$ coefficients was obtained (average difference of ${\pm}15%$), whereas the inaccuracy result (of ${\pm}40%$) was found in Zone B. To enhance the high $k_La$ coefficient and absorption efficiency in bubble column, it was unnecessary to generate numerous fine bubbles at high superficial gas velocity since it causes high power consumption with the great decrease of $k_L$ coefficients.

Characteristics of Algal Abundance and Statistical Analysis of Environmental Factors in Lake Paldang (팔당호 조류발생 특성 및 수질환경인자의 통계적 분석)

  • Park, Hae-Kyung;Lee, Hyun-Ju;Kim, Eun-Kyung;Jung, Dong-Il
    • Journal of Korean Society on Water Environment
    • /
    • v.21 no.6
    • /
    • pp.584-594
    • /
    • 2005
  • The spatio-temporal abundance pattern of algae in Lake Paldang from 2002 to 2004 was investigated. The concentration of chlorophyll a representing algal biomass had fluctuated intensively throughout the year. Among three years, the highest algal biomass was shown in 2002, and typical growth peak of concentration of chlorophyll a was occurred in spring and autumn. There had been frequent rainfall in spring drought period in 2003 and it resulted in the decrease of the algal biomass. The distribution pattern of four algal groups on the surface water of Lake Paldang showed different abundance by season and by water area. In particular, different algal growth characteristics by water areas were observed. Influences of various environmental parameters on algal abundance in four water areas of Lake Paldang were analyzed statistically. From the results of Peason correlation analysis, it was understood that the kinds and affects of environmental parameters were different according to water areas and seasons. Based on the factors analysis of environmental parameters on the concentration of chlorophyll a, stepwise regression models whose independent variables were the factors produced by factor analysis and dependent variable was the concentration of chlorophyll a were derived by water areas and seasons. As a whole, factors related with organics and photosynthesis were revealed to have high affects to algal abundance, whereas limiting nutrients such as phosphorus and nitrogen showed little affect in Lake Paldang.

A Study of the Sound Quality Characteristics for Environmental Noise Assessments Parameters (음질을 고려한 환경소음 평가 인자의 기여도분석에 관한 연구)

  • Jo Kyoung-Sook;Cho Yeon;Hwang Dae-Sun;Hur Deog-Jae
    • The Journal of the Acoustical Society of Korea
    • /
    • v.25 no.3
    • /
    • pp.129-136
    • /
    • 2006
  • For the environmental noise assessments. A weighted equivalent noise level (LeqA) is used to measure the time varying environmental noise. However, it is not appropriately reflect various environmental noise features and human emotions. The human perception of the noise is affected largely by the psychoacoustic characteristics of noise as well as the sound pressure level In this study, the effective factors of noise qualify are analyzed using the subjective assessment and statistical analysis of environmental noise, such as road traffic noise. construction site noise, noise in daily living. and other. The analysis methodology is composed to three steps as follows : firstly, the values of the sound qualify metrics of various noise sources were analyzed. And to classify the noise sources, we conducted a cluster analysis using sound quality metrics. Secondly, subjective jury testing was carried out using the methods of paired comparisons and semantic differential. Finally, the correlation between the subjective parameters and the noise quality metrics were analyzed. As a result. the human perception characteristics of the various environmental noise are described in some physical parameters of the noise qualify metrics.

IDENTIFICATINO OF DYNAMIC PARAMETER OF THE RUBBER CRAVLES SYSTEM FOR FARM MACHINERY

  • Inoue, Eiji;Konya, Hideyuki;Hirai, Yasumaru;Noguchi, Ryozo;Hashiguchi, Koichi;Choe, Jung-Seob
    • Proceedings of the Korean Society for Agricultural Machinery Conference
    • /
    • 2000.11b
    • /
    • pp.146-153
    • /
    • 2000
  • The rubber crawler system for farm machine is composed of driving units such as track rollers, driving sprockets and rubber crawlers. Vibration characteristics of the rubber crawler system varies by driving speed, center of gravity, mass□moment of inertial□location arrangement of track rollers and dynamic parameters such as dynamic spring constant (k) and viscous damping coefficient (c) of a rubber crawler. In general, vibration of the rubber crawler system occurs by reason for mechanical interaction between the rubber crawler and track rollers. Because the dynamic spring constant and viscous damping coefficient vary periodically by mechanical characteristics(deformation characteristics) of the rubber crawler when track rollers drive on the between lugs of the rubber crawler. Therefore, both dynamic parameters k and c were expressed as Fourier series by authors through the shaking test of the rubber crawler and further, vibration characteristics of the rubber crawler system could be simulated analytically. However, actual values of dynamic parameters k and c are different from those obtained by the shaking test because dynamic characteristics of the rubber crawler vary by the effect of variable tension and driving resistance of track rollers. So, actual values of k and c should be identified in the condition of actual driving test. In this study, dynamic parameters such as k and c of the rubber crawler system, which are expressed as Fourier series, were identified using the Gauss-Newton Method. Therefore, validity of identified parameters k and c was discussed through the simulation using experimental data of actual driving test. As a result, in the Fourier series of dynamic parameters of spring constant k and viscous damping coefficient c, excellent parameter convergence and simulation were observed using the Fourier series' zero order and first term of the dynamic model. Furthermore, it was clarified that identification for model parameters which are fitted to actual dynamic motion (vibration) wave of the crawler system was possible by using the time series data observed in vertical and pitching motion of the crawler system.

  • PDF

Micro-Bubble Generating Properties on Gas/Liquid Flow Rate Ratio with the Sludge Flotation/Thickening Apparatus (슬러지 부상농축장치의 기·액 유량비에 따른 미세기포 발생 특성)

  • Lee, Chang-Han;Park, Jong-Won;Ahn, Kab-Hwan
    • Journal of Environmental Science International
    • /
    • v.23 no.1
    • /
    • pp.97-104
    • /
    • 2014
  • The sludge flotation/thickening apparatus equipped a micro-bubble generating pump was used to investigate micro-bubble generating properties on operational parameters. We evaluated micro-bubble generating properties as results to be operated the apparatus by operational parameters which are pump discharge pressure, air/water ratio(A/W ratio), air flow rate, and water flow rate. Micro-bubble generating efficiencies in pumps without recycling flow and with 50% of recycling flow was found to be very efficient on optimum A/W ratio from 1.06 to 3.62% and optimum A/W ratio from 1.05 to 4.06%, respectively. In condition of 3.6% of A/W ratio, we showed that the apparatus could be generated 36,000 ppm of micro-bubble concentration to be optimum treatment efficiency in sludge thickening process.