scholarly journals Downstream prediction using a nonlinear prediction method

2013 ◽  
Vol 10 (11) ◽  
pp. 14331-14354 ◽  
Author(s):  
N. H. Adenan ◽  
M. S. M. Noorani
Keyword(s):  
Phase Space ◽  
Flood Control ◽  
River Flow ◽  
Linear Prediction ◽  
Prediction Method ◽  
Nonlinear Prediction ◽  
Langat River ◽  
Correlation Dimension Method ◽  
The Impact ◽  
Downstream Area

Abstract. The estimation of river flow is significantly related to the impact of urban hydrology, as this could provide information to solve important problems, such as flooding downstream. The nonlinear prediction method has been employed for analysis of four years of daily river flow data for the Langat River at Kajang, Malaysia, which is located in a downstream area. The nonlinear prediction method involves two steps; namely, the reconstruction of phase space and prediction. The reconstruction of phase space involves reconstruction from a single variable to the m-dimensional phase space in which the dimension m is based on optimal values from two methods: the correlation dimension method (Model I) and false nearest neighbour(s) (Model II). The selection of an appropriate method for selecting a combination of preliminary parameters, such as m, is important to provide an accurate prediction. From our investigation, we gather that via manipulation of the appropriate parameters for the reconstruction of the phase space, Model II provides better prediction results. In particular, we have used Model II together with the local linear prediction method to achieve the prediction results for the downstream area with a high correlation coefficient. In summary, the results show that Langat River in Kajang is chaotic, and, therefore, predictable using the nonlinear prediction method. Thus, the analysis and prediction of river flow in this area can provide river flow information to the proper authorities for the construction of flood control, particularly for the downstream area.

Degrees of Freedom

2006 ◽  
Author(s):  
Huug van den Dool
Keyword(s):  
Phase Space ◽  
Degrees Of Freedom ◽  
Prediction Method ◽  
Data Sets ◽  
Nonlinear Prediction ◽  
Orthogonal Direction ◽  
Empirical Prediction ◽  
Long Run ◽  
Dimensional Phase Space ◽  
Natural Analogues

How many degrees of freedom are evident in a physical process represented by f(s, t)? In some form questions about “degrees of freedom” (d.o.f.) are common in mathematics, physics, statistics, and geophysics. This would mean, for instance, in how many independent directions a weight suspended from the ceiling could move. Dofs are important for three reasons that will become apparent in the remaining chapters. First, dofs are critically important in understanding why natural analogues can (or cannot) be applied as a forecast method in a particular problem (Chapter 7). Secondly, understanding dofs leads to ideas about truncating data sets efficiently, which is very important for just about any empirical prediction method (Chapters 7 and 8). Lastly, the number of dofs retained is one aspect that has a bearing on how nonlinear prediction methods can be (Chapter 10). In view of Chapter 5 one might think that the total number of orthogonal directions required to reproduce a data set is the dof. However, this is impractical as the dimension would increase (to infinity) with ever denser and slightly imperfect observations. Rather we need a measure that takes into account the amount of variance represented by each orthogonal direction, because some directions are more important than others. This allows truncation in EOF space without lowering the “effective” dof very much. We here think schematically of the total atmospheric or oceanic variance about the mean state as being made up by N equal additive variance processes. N can be thought of as the dimension of a phase space in which the atmospheric state at one moment in time is a point. This point moves around over time in the N-dimensional phase space. The climatology is the origin of the phase space. The trajectory of a sequence of atmospheric states is thus a complicated Lissajous figure in N dimensions, where, importantly, the range of the excursions in each of the N dimensions is the same in the long run. The phase space is a hypersphere with an equal probability radius in all N directions.

scholarly journals Evaluation Study of Kedunglarangan River To Protect Flood In Pasuruan and Sidoarjo

2019 ◽  
Vol 1 (1) ◽  
pp. 55-62
Author(s):  
Ni Nyoman Adum M
Keyword(s):  
Flood Control ◽  
River Flow ◽  
Water Reservoir ◽  
Evaluation Study ◽  
Water Levels ◽  
Work Study ◽  
Flood Prevention ◽  
River Flood ◽  
Excavation Work ◽  
The Impact

Construction of the Kedunglarangan river flood control system designed to prevent flooding every rainy season in the Bangil sub-district. Kedunglarangan River is a river that flows in two regencies Sidoarjo and Pasuruan which has an area of 282.67 km2 watershed with a river length of 23.7 km. Kedunglarangan river has 4 (four) watershed sub-systems. The scope of this flood prevention work-study is the normalization of the Kedunglarangan River starting from the meeting with the Wrati River downstream up to 7 km. Normalization work is carried out with excavation and river widening to meet flood discharge in accordance with the conditions of the study area. If the river excavation work is done in accordance with the design master will form a basin that causes the creation of a dike. In this condition, it will be a temporary water reservoir where the water velocity is very low. So the work carried out the impact is only temporary. From the results of analysts, it is more efficient to do river widening and embankment raising rather than increasing river depth. River excavation work like that is very risky to create very fast sedimentation. Normalization method with river widening is one way to maintain the river flow downstream and flood water levels

scholarly journals VOICE QUALITY IN MOBILE TELECOMMUNICATION SYSTEM / BALSO KOKYBĖ MOBILIOJO RYŠIO SISTEMOSE

2013 ◽  
Vol 5 (2) ◽  
pp. 150-154
Author(s):  
Evaldas Stankevičius
Keyword(s):  
Correlation Coefficient ◽  
Linear Prediction ◽  
Voice Quality ◽  
Quality Measurement ◽  
Prediction Method ◽  
Mobile Network ◽  
Mobile Telecommunication ◽  
Nonlinear Prediction ◽  
Telecommunication System ◽  
Hardware Configuration

The article deals with methods measuring the quality of voice transmitted over the mobile network as well as related problem, algorithms and options. It presents the created voice quality measurement system and discusses its adequacy as well as efficiency. Besides, the author presents the results of system application under the optimal hardware configuration. Under almost ideal conditions, the system evaluates the voice quality with MOS 3.85 average estimate; while the standardized TEMS Investigation 9.0 has 4.05 average MOS estimate. Next, the article presents the discussion of voice quality predictor implementation and investigates the predictor using nonlinear and linear prediction methods of voice quality dependence on the mobile network settings. Nonlinear prediction using artificial neural network resulted in the correlation coefficient of 0.62. While the linear prediction method using the least mean squares resulted in the correlation coefficient of 0.57. The analytical expression of voice quality features from the three network parameters: BER, C / I, RSSI is given as well. Article in Lithuanian. Santrauka Nagrinėjama mobiliuoju tinklu perduoto balso kokybės matavimo metodikos problematika, balso kokybės įvertinimo algoritmų pasirinkimo galimybės. Aptariamas sukurtos balso kokybės matavimo sistemos tinkamumas, efektyvumas. Pateikiami sukurtos sistemos taikymo rezultatai parinkus optimalią įrangos konfigūraciją. Sąlygomis, artimomis idealioms, gauta, kad sukurta sistema balso kokybę įvertina vidutiniu 3,85 MOS įverčiu, o standartizuota TEMS Investigation 9.0 – vidutiniu 4,05 MOS įverčiu. Aptarta balso kokybės prognozatoriaus sukūrimo galimybė. Ištirtas balso kokybės priklausomybės nuo mobiliojo tinklo parametrų prognozatorius, taikantis tiesinės ir netiesinės prognozės būdus. Netiesinė prognozė, taikant dirbtinius neuronų tinklus, teikia 0,62 koreliacijos koeficientą. Tiesinė prognozė mažiausiųjų kvadratų metodu teikia 0,57 koreliacijos koeficientą. Gauta analitinė balso kokybės funkcijos išraiška nuo trijų tinklo parametrų: BER, C/I, RSSI.

scholarly journals Study on the Assessment Method of the Impact on Hydrological Safety of Riverside Pit-Ponds along a Dike

Water ◽  
2019 ◽  
Vol 11 (4) ◽  
pp. 744
Author(s):  
Shuai Liu ◽  
Dewei Yang ◽  
Jinbao Sheng ◽  
Jiankang Chen ◽  
Chengjun Xu ◽  
...  
Keyword(s):  
Mathematical Model ◽  
Flood Control ◽  
River Flow ◽  
Yellow River ◽  
Assessment Method ◽  
Present Condition ◽  
Two Dimensional ◽  
Safety Review ◽  
The Impact ◽  
Hydrological Safety

Riverside pit-ponds are one of the hidden dangers of flood control project safety. At present, the safety evaluation of riverside pit-ponds is limited to the seepage and stable safety review of the dam, and the impact of the pit on the river flow is not considered. In this paper, a two-dimensional mathematical model of flow is established. Pressure correction method is used to solve the pressure-velocity coupling. Topographic cutting method is used to deal with the dynamic boundary problem. The model grid of the pit-ponds area is encrypted. The accuracy of the model in the analysis of river hydrodynamics is verified by an example. The model is applied to the evaluation of the impact of the pit-ponds on river flooding. Taking some riverside pit-ponds of the Yellow River as an example, the river water level, velocity, and flow in the present condition and the backfill condition are simulated by the model. The results show that the existence of these riverside pit-ponds only affects the hydrological features of regions around the pit-ponds, and the impact is too insignificant to threaten the hydrological safety. Through the hydrological safety assessment of the project, it is shown that the combination of the two-dimensional flow mathematical model with seepage, anti-sliding, and seismic safety review can comprehensively assess the hydrological safety of dike engineering.

scholarly journals Derivation of effective and efficient data set with subtractive clustering method and genetic algorithm

2005 ◽  
Vol 7 (4) ◽  
pp. 219-233 ◽  
Author(s):  
C. D. Doan ◽  
S. Y. Liong ◽  
Dulakshi S. K. Karunasinghe
Keyword(s):  
Genetic Algorithm ◽  
Fuzzy Logic ◽  
Phase Space ◽  
Prediction Accuracy ◽  
River Flow ◽  
Prediction Method ◽  
Subtractive Clustering ◽  
Clustering Method ◽  
Data Set ◽  
Subtractive Clustering Method

Success of any forecasting model depends heavily on reliable historical data, among others. Data are needed to calibrate, fine tune and verify any simulation model. However, data are very often contaminated with noise of different levels originating from different sources. This study proposes a scheme that extracts the most representative data from a raw data set. Subtractive Clustering Method (SCM) and Micro Genetic Algorithm (mGA) were used for this purpose. SCM does (a) remove outliers and (b) discard unnecessary or superfluous points while mGA, a search engine, determines the optimal values of the SCM's parameter set. The scheme was demonstrated in: (1) Bangladesh water level forecasting with Neural Network and Fuzzy Logic and (2) forecasting of two chaotic river flow series (Wabash River at Mt. Carmel and Mississippi River at Vicksburg) with the phase space prediction method. The scheme was able to significantly reduce the data set with which the forecasting models yield either equally high or higher prediction accuracy than models trained with the whole original data set. The resulting fuzzy logic model, for example, yields a smaller number of rules which are easier for human interpretation. In phase space prediction of chaotic time series, which is known to require a long data record, a data reduction of up to 40% almost does not affect the prediction accuracy.

scholarly journals Impact of human and environmental interactions on flooding incident in the Jeneberang River South Sulawesi

2021 ◽  
Vol 886 (1) ◽  
pp. 012105
Author(s):  
St. Khadijah Munirah Wahid ◽  
Daud Malalassam ◽  
Roland A. Barkey ◽  
Baharuddin
Keyword(s):  
Flood Control ◽  
River Flow ◽  
Environmental Conservation ◽  
Human Interaction ◽  
Primary Data ◽  
Physical Factors ◽  
Infrastructure Development ◽  
South Sulawesi ◽  
Environmental Interactions ◽  
The Impact

Abstract Human interaction with the environment due to negative impacts. This can be seen, among others, in the interaction of the community with the environment in the Jeneberang watershed area, South Sulawesi Province, which has an impact in the form of flood events. This paper aims to determine the extent of the impact of human and environmental interactions on flooding in the area. The study was carried out through several studies and studies on human interactions and the natural environment in the Jeneberang watershed, literature studies, reviewing and concluding various journals, as well as collecting data through analysis of maps and secondary data from relevant agencies and primary data from the community as the main actors. The results of the study indicate that human interaction with the environment in the Jeneberang watershed has an impact in the form of flooding because the Jeneberang watershed management activities have not been optimally integrated, which are indicated by: 1. Watershed characteristics are not taken into account in infrastructure development. 2. There is still limited understanding of land-use communities about the characteristics of rainfall and surface runoff, as well as their relation to landslides and sedimentation, 3. The influence of mining activities on river flow narrowing and dam silting is not taken into account, and 4. The occurrence of vegetation degradation in downstream. In order to optimize flood control efforts in the Jeneberang river, it is necessary to carry out integrated management of the Jeneberang watershed by integrating all activities in all sectors. Planning for flood control and environmental conservation in general needs to really consider physical factors in the form of climate, hydrology, geology, tectonics, in addition to vegetation, management, technology, and socio-economic and cultural factors. Communities need to be motivated to continue trying to increase their income and welfare, accompanied by efforts to increase understanding and awareness of the importance of maintaining and preserving the environment, through diversifying livelihoods and utilizing natural resources and land that always prioritizes conservation aspects.

scholarly journals Flood control at km 130 Padaleunyi Toll

2019 ◽  
Vol 270 ◽  
pp. 04013
Author(s):  
Suci Anggraeni ◽  
Arno Adi Kuntoro ◽  
Mohammad Farid ◽  
Dhemi Harlan ◽  
M. Bagus Adityawan
Keyword(s):  
Cross Sections ◽  
Catchment Area ◽  
Flood Control ◽  
River Flow ◽  
Vertical Wall ◽  
Measurement Data ◽  
Road Segment ◽  
Toll Road ◽  
Increased Risk ◽  
The Impact

Flood is one of the natural phenomena that often brings loss of property and life. Mostly, it occurs during a high-intensity rainfall event in the catchment area which results in high river flow that cannot be accommodated by river cross sections. In Bandung area, one of the locations that are often hit by the flood is located on km 130 of the Padaleunyi toll road. This flood occurred due to the overflow of the Cilember and/or Cimancong rivers tributary which flows parallel to the toll road, inundating the toll road segment with low elevation at around km 130+500. This paper aims to analyze the effective flood control methods in the above location. With catchment area around 2.3km2, which is relatively small, peak flood discharge calculation was carried out using a rational method. Hydraulics simulation was carried out using HecRas, based on river field measurement data of Cilember and Cimancong river cross-section. Analysis result shows that the combination between flood embankment construction and river normalization provides a significant decrease in flood water level in km 130 Padaleunyi toll road. The reinforced concrete vertical wall was considered as the appropriate flood protections structure due to the limited space available between the river and the toll road segment. This paper also underlined the impact of the increasing loss of water retention areas on an increased risk of flooding.

scholarly journals Dynamics of monthly rainfall-runoff process at the Gota basin: A search for chaos

2000 ◽  
Vol 4 (3) ◽  
pp. 407-417 ◽  
Author(s):  
B. Sivakumar ◽  
R. Berndtsson ◽  
J. Olsson ◽  
K. Jinno ◽  
A. Kawamura
Keyword(s):  
Prediction Accuracy ◽  
Correlation Dimension ◽  
Prediction Method ◽  
Monthly Rainfall ◽  
Runoff Coefficient ◽  
Embedding Dimension ◽  
Rainfall Runoff ◽  
Nonlinear Prediction ◽  
Runoff Series ◽  
Correlation Dimension Method

Abstract. Sivakumar et al. (2000a), by employing the correlation dimension method, provided preliminary evidence of the existence of chaos in the monthly rainfall-runoff process at the Gota basin in Sweden. The present study verifies and supports the earlier results and strengthens such evidence. The study analyses the monthly rainfall, runoff and runoff coefficient series using the nonlinear prediction method, and the presence of chaos is investigated through an inverse approach, i.e. identifying chaos from the results of the prediction. The presence of an optimal embedding dimension (the embedding dimension with the best prediction accuracy) for each of the three series indicates the existence of chaos in the rainfall-runoff process, providing additional support to the results obtained using the correlation dimension method. The reasonably good predictions achieved, particularly for the runoff series, suggest that the dynamics of the rainfall-runoff process could be understood from a chaotic perspective. The predictions are also consistent with the correlation dimension results obtained in the earlier study, i.e. higher prediction accuracy for series with a lower dimension and vice-versa, so that the correlation dimension method can indeed be used as a preliminary indicator of chaos. However, the optimal embedding dimensions obtained from the prediction method are considerably less than the minimum dimensions essential to embed the attractor, as obtained by the correlation dimension method. A possible explanation for this could be the presence of noise in the series, since the effects of noise at higher embedding dimensions could be significantly greater than that at lower embedding dimensions. Keywords: Rainfall-runoff; runoff coefficient; chaos; phase-space; correlation dimension; nonlinear prediction; noise

scholarly journals Multivariate Nonlinear Analysis and Prediction of Shanghai Stock Market

2008 ◽  
Vol 2008 ◽  
pp. 1-8 ◽  
Author(s):  
Junhai Ma ◽  
Lixia Liu
Keyword(s):  
Time Series ◽  
Prediction Model ◽  
Stock Returns ◽  
Stock Price ◽  
Linear Prediction ◽  
Stock Exchange ◽  
Multivariate Time Series ◽  
Prediction Method ◽  
Nonlinear Prediction ◽  
Stock Price Prediction

This study attempts to characterize and predict stock returns series in Shanghai stock exchange using the concepts of nonlinear dynamical theory. Surrogate data method of multivariate time series shows that all the stock returns time series exhibit nonlinearity. Multivariate nonlinear prediction methods and univariate nonlinear prediction method, all of which use the concept of phase space reconstruction, are considered. The results indicate that multivariate nonlinear prediction model outperforms univariate nonlinear prediction model, local linear prediction method of multivariate time series outperforms local polynomial prediction method, and BP neural network method. Multivariate nonlinear prediction model is a useful tool for stock price prediction in emerging markets.

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