作者:
Andrzej SzarataaCracow University of Technology
Institute of Road and Railway Engineering Department of Transportation Systems Warszawska 24 31-155 Kraków Poland tel. 0048 12 628 30 84 aszarata@pk.edu.pl
The conducted survey were aimed on estimation of the number of potential Park and Ride users. The system is not popular in Poland and it is difficult to estimate (and calibrate) modal split function based on Stated Pr...
The conducted survey were aimed on estimation of the number of potential Park and Ride users. The system is not popular in Poland and it is difficult to estimate (and calibrate) modal split function based on Stated Preferences survey. Because fuzzy approach can be justified in the case of rough data and significant impact of human factors, it is difficult to estimate necessary functions using traditional mathematical approach. It seems, that fuzzy methodology can be treated as a proper way to describe choice of mode of transport, especially in case of Park and Ride trips. The proposed approach is based on the Mamdani Fuzzy Inference System, where, as the part of the model, the membership functions were estimated according to the experts’ survey. The survey had two level verification using Delphic approach and final results were obtained as an approximation of shapes of the functions proposed by experts. The methodology were tested on the real system implemented in Warsaw. The paper will present procedure for membership function estimation, application of the model. For calculation there was used Matlab software, with Fuzzy Logic Toolbox. Main goal of the paper is to present complexity and uncertainty of the modal split modeling process.
The Orthosiphon stamineus spray-dried powder have many benefits for human consumption either as supplement or natural herbal medicinal. It can cure many diseases especially urinary tract, diabetic and kidney stones. T...
The Orthosiphon stamineus spray-dried powder have many benefits for human consumption either as supplement or natural herbal medicinal. It can cure many diseases especially urinary tract, diabetic and kidney stones. The moisture sorption isotherm is very important to identify the desirable storage condition and the shelf life of O. stamineus spray-dried powder. Moisture sorption isotherm of O. stamineus extract powder were determined through the gravimetric method at two selected temperature which were 4 and 30 °C. Five type of different saturated salts such as lithium chloride, magnesium chloride, potassium carbonate, sodium bromide and potassium nitrate were used in this study. The setup range of relative humidity were 11 to 95%. There were two type of mathematicalmodelling used to validate the data that have been taken from the research work which are GAB and BET model. Based on the results, it was found that the GAB model shows the best fit model as all the data from this research have the nearest value of the GAB fitting criteria. This is due to the value of coefficient of correlation, R2 = 0.998 at 30 °C in adsorption process.
作者:
Mircea BarnaureDaniel ManoliFaculty of Civil
Industrial and Agricultural Buildings Technical University of Civil Engineering Bucharest 122 - 124 Lacul Tei Blv 020396 Bucharest Romania
The soil-structure interaction (SSI) effects can substantially alter the behaviour of structures during earthquakes. Implementation of SSI within the seismic analysis often leads to lower stresses in the structure and...
The soil-structure interaction (SSI) effects can substantially alter the behaviour of structures during earthquakes. Implementation of SSI within the seismic analysis often leads to lower stresses in the structure and therefore a more economical design. The recently introduced provisions in European and American codes allow for this type of approach. However, consideration of SSI can also lead to the observation of unfavourable effects (undetectable in a fixed-base analysis) due to the modification of the structure's dynamic properties. Examples of unfavourable effects include higher global displacements or story drifts, increases of the base or story shear forces, higher post-elastic demands in the structural members or the collision of adjacent buildings separated by an insufficient structural joint. These unfavourable effects can be related to various parameters such as the structural system (frames or shear walls), foundation type (shallow or piles), geometry of the foundation, height of the building, soil type, seismic input, presence of adjacent buildings, etc. Under these circumstances, the integration of SSI into the current structural design becomes essential. As the mathematical formulation of the phenomenon is very complex and involves many parameters, the definition of complete numerical models is difficult. The provisions in the codes are often general and do not give the practicing engineers clear modelling solutions. An analysis of the current situation in the field of SSI is carried out, with a focus on the design of reinforced concrete structures. Based on an extensive literature review, the unfavourable seismic effects and the main parameters that determine them are identified. Conclusions are drawn regarding the situations when SSI should be mandatory and on the different possibilities of implementing SSI in the structural design.
The most important application of various geotechnical construction techniques is for ground improvement. Many soil improvement project had been developed due to the ongoing increase in urban and industrial growth and...
The most important application of various geotechnical construction techniques is for ground improvement. Many soil improvement project had been developed due to the ongoing increase in urban and industrial growth and the need for greater access to lands. Stone columns are one of the best effective and feasible techniques for soft clay soil improvement. Stone columns increase the bearing capacity and reduce the settlement of soil. Finite element analyses were performed using the program PLAXIS 2D. An elastic-perfectly plastic constitutive relation, based on the Mohr–Coulomb criterion, governs the soft clay and stone column behaviour. This paper presents on how the response surface methodology (RSM) software is used to optimize the effect of the diameters and lengths of column on the load bearing capacity and settlement of soft clay. Load tests through the numerical modelling using Plaxis 2D were carried out on the loading plate at 66 mm. Stone column load bearing capacity increases with the increasing diameter of the column and settlement decreases with the increasing length of the column. Results revealed that the bigger column diameter, the higher load bearing capacity of soil while the longer column length, the lower settlement of soil. However, the optimum design of stone column was varied with each factor (diameter and length) separately for improvement.
To analyze the water budget under human influences in the Isser wadi alluvial aquifer in the northeast of Algeria, we built a mathematical model which can be used for better managing groundwater exploitation. A modula...
To analyze the water budget under human influences in the Isser wadi alluvial aquifer in the northeast of Algeria, we built a mathematical model which can be used for better managing groundwater exploitation. A modular three-dimensional finite-difference groundwater flow model (MODFLOW) was used. The modelling system is largely based on physical laws and employs a numerical method of the finite difference to simulate water movement and fluxes in a horizontally discretized field. After calibration in steady-state, the model could reproduce the initial heads with a rather good precision. It enabled us to quantify the aquifer water balance terms and to obtain a conductivity zones distribution. The model also highlighted the relevant role of the Isser wadi which constitutes a drain of great importance for the aquifer, ensuring alone almost all outflows. The scenarios suggested in transient simulations showed that an increase in the pumping would only increase the lowering of the groundwater levels and disrupting natural balance of aquifer. However, it is clear that this situation depends primarily on the position of pumping wells in the plain as well as on the extracted volumes of water. As proven by the promising results of model, this physically based and distributed-parameter model is a valuable contribution to the ever-advancing technology of hydrological modelling and water resources assessment.
Tsunamis are uncommon events compared to natural hazards. Population growth along the shorelines has increased the statistic of the number of victims affected by the tsunami disaster. In order to help people to be awa...
Tsunamis are uncommon events compared to natural hazards. Population growth along the shorelines has increased the statistic of the number of victims affected by the tsunami disaster. In order to help people to be aware about the tsunami disasters, tsunami wave propagation must be predicted. This study proposes a one-dimensional coupled shallow water equation for predicting the tsunami wave propagation. The simulation of numerical modelling was conducted to predict the occurrence of tsunami wave propagation. In order to approximate the shallow water equation, the discretization process was conducted using a new semi-implicit method which is one of the methods in finite difference method. A problem regarding the free surface wave damping problem were used in validating the semi-implicit method. For the purposes of the simulation, the boundary condition and initial condition, the spatial steps and time steps as well as the approximation of shallow water equation were encoded. By comparing the simulation results with Park (2007), we found that the simulation of one-dimensional shallow water equation is successfully predicted the behaviour of the tsunami propagation near the coastline after the earthquake ground shaking occurred.
This study is concerned with modelling and analyses of a vibro-impact system consisting of a crank-slider mechanism and one oscillator attached to it, where the system can be exposed to ideal or non-ideal excitation. ...
This study is concerned with modelling and analyses of a vibro-impact system consisting of a crank-slider mechanism and one oscillator attached to it, where the system can be exposed to ideal or non-ideal excitation. The impact occurs during the motion of the oscillator when it hits a base, and the excitation of the driving source is affected by this behaviour. The aim is to determine the interaction between a driving torque and the motion of the oscillator. To achieve this aim in a methodologically sound manner, both vibro-impact systems with ideal and non-ideal excitation are analysed. For these system differential equations are formed and the impact model is provided in the paper. The impact causes a strong nonlinearity in the system. The mathematical model of the vibro-impact system with ideal excitation is presented as a second order differential equation where the vibro-impact system with non-ideal excitation is given as a coupled system of nonlinear second order differential equations. Numerical simulations are carried out for the two systems and the results obtained are shown in terms of frequency response diagrams as well as in terms of time-displacement diagrams. The results found for different systems are compared mutually, and the differences between them are pointed out. Impact solutions for different regions of the excitation frequency are shown. For a specific value of the excitation frequency in the frequency response diagram where multiple solutions are found, basin of attractor diagrams are formed. Average value of the excitation frequency is used for the vibro-impact system with non-ideal excitation.
Every product is growingly being evaluated in terms of acoustic characteristics. The most accurate way to rate sound quality is by performing jury tests; however, jury tests require a lot of time and human resources. ...
Every product is growingly being evaluated in terms of acoustic characteristics. The most accurate way to rate sound quality is by performing jury tests; however, jury tests require a lot of time and human resources. To overcome this problem, jury tests results can be correlated to objective sound quality metrics owing to the fact that objective metrics could be easily obtained from sound data. In this study, advanced techniques for feature identification are explored to correlate objective metrics to subjective perception retrieved from jury tests. The data set referes to the interior noise of a regional propeller aircraft. Artificial Neural Network and two regression models (i.e. linear and quadratic regression models) have been chosen to predict subjective metrics according to the objective data. To obtain the optimized model parameters for the regression models, a Genetic Algorithm has been used as optimization strategy. In each modelling, 85 percent of sound sample data have been utilized to perform the model and remaining 15 percent have been reserved for testing the models. The results showed that the Artificial Neural Network can provide better prediction.
Good quality data is important to guarantee for the best quality results of research analysis. However, the quality of the data often being impacted by the existence of missing values that bring bad implication on the...
Good quality data is important to guarantee for the best quality results of research analysis. However, the quality of the data often being impacted by the existence of missing values that bring bad implication on the accuracy of analysis and subsequently lead to biased results. In air quality data set, missing values problem often caused by various reasons, for example machine malfunction and errors, computer system crashes, human error and insufficient sampling used. In the case for time series modelling, complete series of data is very important to enable for the model construction. This paper aims to highlight a systematic statistical procedure and analysis on how to investigate the performance of several missing values imputation methods to solve for the problem of missing value existence when data are time series. The knowledge could help researchers to implement a comprehensive procedure in deciding a type of imputation method that suits with their data. A case study was conducted using real data set from Shah Alam air quality monitoring station. The results have shown that the missing data at the monitoring station is completely at random (MCAR). Among six imputation methods compared and based on the performance of indicators such as RMSE, MAE, AI and R2 it is shown that imputation using Kalman Filter using ARIMA model is the best appropriate method for the data set.
The overarching goal of the Medical Waste Management Plan is to avoid and/or reduce the detrimental impacts of medical waste on human health and the environment. Design is the method through which humans achieve their...
The overarching goal of the Medical Waste Management Plan is to avoid and/or reduce the detrimental impacts of medical waste on human health and the environment. Design is the method through which humans achieve their intended results. The design of the Smart waste container is quite sophisticated since the Smart waste container operates in a very complicated environment. To acquire the best and most suitable design of Smart waste container to withstand various stresses and pressures, finite element analysis with Solidworks suggests the minimal design standard. Pro/Engineer Solidworks 2018 for finite element analysis is used for this purpose. Optimization is a procedure that delivers the optimum choice and outcome. Following observation and modelling, an optimization study was carried out. It is concerned with weight comparison and minimizing the size of the Smart waste container by analyzing numerous elements that impact performance, such as stress. The purpose of doing this research was to demonstrate the Container behaviour impacted by fatigue phenomena owing to fatigue tests and to examine the results for additional time and cost, as two extremely important metrics related to production. The analysis shows that with totally continual loading, it is possible to predict the lifespan of a Smart Waste container but also identify the crucial spots when crack formation is most likely to occur. The fatigue results we obtained for the improved design were Alternating Stress (1.72E+05 N/m^2) Cycles 1.00E+06 Which shows that the design is good and has a long service life.
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