• Title/Summary/Keyword: parallel reservoir groups

Search Result 3, Processing Time 0.015 seconds

Streamflow Estimation using Coupled Stochastic and Neural Networks Model in the Parallel Reservoir Groups (추계학적모형과 신경망모형을 연계한 병렬저수지군의 유입량산정)

  • Kim, Sung-Won
    • Journal of Korea Water Resources Association
    • /
    • v.36 no.2
    • /
    • pp.195-209
    • /
    • 2003
  • Spatial-Stochastic Neural Networks Model(SSNNM) is used to estimate long-term streamflow in the parallel reservoir groups. SSNNM employs two kinds of backpropagation algorithms, based on LMBP and BFGS-QNBP separately. SSNNM has three layers, input, hidden, and output layer, in the structure and network configuration consists of 8-8-2 nodes one by one. Nodes in input layer are composed of streamflow, precipitation, pan evaporation, and temperature with the monthly average values collected from Andong and Imha reservoir. But some temporal differences apparently exist in their time series. For the SSNNM training procedure, the training sets in input layer are generated by the PARMA(1,1) stochastic model and they covers insufficient time series. Generated data series are used to train SSNNM and the model parameters, optimal connection weights and biases, are estimated during training procedure. They are applied to evaluate model validation using observed data sets. In this study, the new approaches give outstanding results by the comparison of statistical analysis and hydrographs in the model validation. SSNNM will help to manage and control water distribution and give basic data to develop long-term coupled operation system in parallel reservoir groups of the Upper Nakdong River.

Fluticasone Propionate and Beclomethasone Dipropionate in Asthmatic Patients (천식환자에서 Fluticasone propionate와 Beclomethasone dipropionate의 치료효과 비교)

  • Yang, Dong-Kyu;Kim, Young-Sam;Ahn, Chul-Min;Ko, Won-Ki;Chang, Joon;Kim, Sung-Kyu;Lee, Won-Young
    • Tuberculosis and Respiratory Diseases
    • /
    • v.47 no.5
    • /
    • pp.629-641
    • /
    • 1999
  • Background: Corticosteroid is most potent and effective anti-inflammatory medication currently available and inhaled form has been used in the long-tenn control of asthma. Fluticasone propionate(Flixotide/Flovent: FP) is highly potent and topically active inhaled corticosteroid and has at least twice the potency of beclomethasone dipropionate(BDP) in the control of asthma. The aim of this study was to compare the efficacy of FP and BDP in several aspects. Method: Fifty patients with asthma were treated in a randomized, parallel group study of 4 weeks duration. During 2-week run-in period $\beta_2$-agonist was administered. After run-in period, FP $500{\mu}g/day$ was administered via Diskhaler or BDP $800{\mu}g/day$ via reservoir dry-power device. During the run-in and treatment period, morning and evening peak expiratory flow rate(PEFR) were measured daily. Daytime and nighttime asthma symptoms, daytime and night-time rescue bronchodilator use were checked daily. $FEV_{1.0}$ and FVC were measured biweekly in both groups. Results: Three patients treated with FP and seven patient treated with BDP were dropped out. Therefore forty patients completed the study. Morning and evening PEFR was increased and diurnal variation of PEFR decreased significantly in both groups. $FEV_{1.0}$ increased significantly in FP treatment group but not in BDP group. There were also improvements in daytime and night-time asthma symptoms, daytime and night-time rescue bronchodilator use in both groups after treatment There were no significant difference between groups in any of the efficacy parameters. Therapeutic effects were demonstrated earlier in patient treated with FP than BDP. Conclusion: In this study, $500{\mu}g/day$ fluticasone propionate was as effective as $800{\mu}g/day$ beclomethasone dipropionate in the control of asthma. Therapeutic effects were demonstrated earlier in patient treated with FP than BDP without adverse effect.

  • PDF