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Open access

Janusz Bogusz, Anna Klos, Marta Gruszczynska and Maciej Gruszczynski

Abstract

In the modern geodesy the role of the permanent station is growing constantly. The proper treatment of the time series from such station lead to the determination of the reliable velocities. In this paper we focused on some pre-analysis as well as analysis issues, which have to be performed upon the time series of the North, East and Up components and showed the best, in our opinion, methods of determination of periodicities (by means of Singular Spectrum Analysis) and spatio-temporal correlations (Principal Component Analysis), that still exist in the time series despite modelling. Finally, the velocities of the selected European permanent stations with the associated errors determined following power-law assumption in the stochastic part is presented.

Open access

Dorota Latos, Bogdan Kolanowski, Wojciech Pachelski and Ryszard Sołoducha

Abstract

Real time monitoring of engineering structures in case of an emergency of disaster requires collection of a large amount of data to be processed by specific analytical techniques. A quick and accurate assessment of the state of the object is crucial for a probable rescue action. One of the more significant evaluation methods of large sets of data, either collected during a specified interval of time or permanently, is the time series analysis. In this paper presented is a search algorithm for those time series elements which deviate from their values expected during monitoring. Quick and proper detection of observations indicating anomalous behavior of the structure allows to take a variety of preventive actions. In the algorithm, the mathematical formulae used provide maximal sensitivity to detect even minimal changes in the object’s behavior. The sensitivity analyses were conducted for the algorithm of moving average as well as for the Douglas-Peucker algorithm used in generalization of linear objects in GIS. In addition to determining the size of deviations from the average it was used the so-called Hausdorff distance. The carried out simulation and verification of laboratory survey data showed that the approach provides sufficient sensitivity for automatic real time analysis of large amount of data obtained from different and various sensors (total stations, leveling, camera, radar).

Open access

Time Series Approach To Athletes Motor Potential

Time series approach to motor potential

Adam Maszczyk, Robert Roczniok, Przemysław Pietraszewski, Arkadiusz Stanula, Adam Zając and Artur Gołaś

Abstract

Introduction. The aim of this study was to determine the dynamics of changes in selected motor abilities of javelin throwers and to determine predictors of javelin throw distances. Material and methods. Research material included the results obtained from a group of 60 competitors from the Silesia Region of Poland, aged 14 - 15 years. In order to answer the research question, the following statistical analysis were employed: Pearson's linear correlation coefficients, vectors R0 and R1, time series analysis, distributed lag analysis and Almon distributed lag analysis and coefficient of concordance φ2 Results. The correlation analyzes allowed for a selection of two variables for further analyses: specific strength of arms and trunk (SSAT) and specific strength of shoulders girdle and trunk (SSGT). Calculated indexes revealed that the level of SSAT showed a constant upward tendency (+15%). The highest rise in SSAT level was recorded in the 4th and 5th quarter (+9%). The level of SSGT showed an upward tendency nearly (+6%). In this case, the highest rise was observed in the 7th and 8th quarter (+4.5%). Conclusions. The standardized regression analysis revealed that the variable of specific power of arms and trunk (SOBT) is the most important predictor for javelin throw distance with a full approach run.

Open access

Arnis Kirshners and Yuri Kornienko

Time-Series Data Mining for E-Service Application Analysis

This paper provides application analysis of e-services available on the joint state and municipal e-service portal www.latvija.lv. The research is performed using a combination of time series analysis and data mining techniques. Time series analysis has enabled the determination of the count of clusters that represent services classification by application frequency. Meta-information is processed using data pre-processing methods and the values obtained are then discretised. The methods combinations examined in the paper are tested experimentally on the limited data amount available. The data describe the existing e-service requests by months. The clusters obtained are then added to the initial meta-information available when planning and developing services. E-service membership in the formed data set is determined using inductive classification trees. These algorithms represent knowledge in the form of classification trees through analysing feature values and cyclically split training instances into classes. As a result, based on the analysis conducted, recommendations for e-service developers and implementers are elaborated and basic parameters for successful introduction and application of e-services are determined.

Open access

Wiesław Miczulski and Łukasz Sobolewski

Influence of the GMDH Neural Network Data Preparation Method on UTC(PL) Correction Prediction Results

The article presents results of the influence of the GMDH (Group Method of Data Handling) neural network input data preparation method on the results of predicting corrections for the Polish timescale UTC(PL). Prediction of corrections was carried out using two methods, time series analysis and regression. As appropriate to these methods, the input data was prepared based on two time series, ts1 and ts2. The implemented research concerned the designation of the prediction errors on certain days of the forecast and the influence of the quantity of data on the prediction error. The obtained results indicate that in the case of the GMDH neural network the best quality of forecasting for UTC(PL) can be obtained using the time-series analysis method. The prediction errors obtained did not exceed the value of ± 8 ns, which confirms the possibility of maintaining the Polish timescale at a high level of compliance with the UTC.

Open access

Jerzy Parysek and Lidia Mierzejewska

Trajectories of the demographic development of Poland after 1989

One of the major problems of contemporary Poland is its increasingly difficult and complicated demographic situation. This makes the identification of demographic trends of the recent years an important research task. The article presents an assessment of Poland's demographic situation after 1989, i.e. after the change of the country's socio-political system, using the graphic method of trajectories. It is one of the possible, though less popular, methods of studying time series, offering a new perspective on various processes, here demographic ones. The article has two aims: cognitive and methodological.

Open access

Aleksandrs Dahs

Abstract

In recent decades, scientific literature on demographic research is increasing attention on spatial data analysis. It is considered a useful and reliable analysis methodology in evaluating complex regional development processes. However, due to its complexity and reliance on properly captured and quantified spatial relations, it remains a difficult topic for many scholars and practitioners. In Latvia, spatial demographic analysis may prove useful, providing opportunities for uncovering new dimensions of long-term regional demographic and economic development issues. Here, the author analyses spatial distribution aspects of key demographic indicators in Latvia’s municipalities, the associated socio-economic factors and their impact. The implications of the identified spatial processes and dependencies for regional development policy and aid are discussed, including possible lessons learned from or shared with the EU Eastern Partnership countries facing similar challenges.

Open access

Mohamed Soua

Time series analysis (orbital cycles) of the uppermost Cenomanian-Lower Turonian sequence on the southern Tethyan margin using foraminifera

Time series analysis has been performed for the first time on the Cenomanian-Turonian sequence in Central Tunisia in order to shed light on its Milankovitch-like cyclicity. This analysis was applied to two foraminiferal genera: the biserial Heterohelix, an oxygen-minimum zone (OMZ) dweller, and the triserial Guembelitria, a eutrophic surface dweller. Average sedimentary rates and the duration of the oceanic anoxic event (OAE2) in each studied section were estimated. The fluctuations in abundance of these two opportunistic species can be related mainly to both precessional (ca. 20 kyr) and eccentricity (100 and 400 kyr) cyclicity suggesting that changes in surface water fertility were linked to climate changes in the Milankovitch frequency band.

Open access

Svetlana Bičárová and Ladislav Holko

Abstract

The article presents the results of the analysis of time series of daily precipitation and runoff at selected places in the highest part of the Western Carpathians. It was focused on both wet and dry periods in precipitation and runoff data series. The precipitation data were analysed for a period 1961-2010. They revealed a significant increase of the number of days with daily precipitation 40-60 mm. Trend analysis for 67 analysed flow characteristics did not show statistically significant changes over the studied period. The focus was given particularly to the characteristics of the maximum and minimum flows, i.e. 3- and 7- day minimum flows, 1-, 3- and 7-day maximum flows. We found an increase of flows classified as small floods in two of three mountain catchments in the study area in the last decade (2001-2010). It may be linked to the above increased number of days with daily precipitation reaching 40-60 mm.

Open access

Ivan Nesmerak and Sarka D. Blazkova

Abstract

Time series of the daily total precipitation, daily wastewater discharges and daily concentrations and pollution loads of BOD5, COD, SS, N-NH4, Ntot and Ptot were analyzed at the inflow to the wastewater treatment plant (WWTP) for a larger city in 2004-2009 (WWTP is loaded by pollution from 435,000 equivalent inhabitants). The time series of the outflow from a WWTP was also available for 2007. The time series of daily total precipitation, daily wastewater discharges, concentrations and pollution loads at the inflow and outflow from the WWTP were standardized year by year to exclude a long-term trend, and periodic components with a period of 7 days and 365 days (and potentially also 186.5 days) were excluded from the standardized series. However, these two operations eliminated only a small part of the variance; there was a substantial reduction in the variance only for ammonium nitrogen and total nitrogen at the inflow and outflow from a WWTP. The relationship between the inflow into a WWTP and the outflow from a WWTP for the concentrations and pollution loads was described by simple transfer functions (SISO models) and more complicated transfer functions (MISO models). A simple transfer function (SISO model) was employed to describe the relationship between the daily total precipitation and the wastewater discharge.