Potential of support-vector regression for forecasting stream flow

Vodotok je važan za hidrološko proučavanje zato što određuje varijabilnost vode i magnitudu rijeke. Inženjerstvo vodnih resursa uvijek se bavi povijesnim podacima i pokušava procijeniti prognostičke podatke kako bi se osiguralo bolje predviđanje za primjenu kod bilo kojeg vodnog resursa, na pr. projektiranja vodnog potencijala brane hidroelektrana, procjene niskog protoka, i održavanja zalihe vode. U radu se predstavljaju tri računalna programa za primjenu kod rješavanja ovakvih sadržaja, tj. umjetne neuronske mreže - artificial neural networks (ANNs), prilagodljivi sustavi neuro-neizrazitog zaključivanja - adaptive-neuro-fuzzy inference systems (ANFISs), i support vector machines (SVMs). Za stvaranje procjene korištena je Rijeka Telom, smještena u Cameron Highlands distriktu Pahanga, Malaysia. Podaci o dnevnom prosječnom protoku rijeke Telom, kao što su količina padavina i podaci o vodostaju, koristili su se za period od ožujka 1984. do siječnja 2013. za podučavanje, ispitivanje i ocjenjivanje izabranih modela. SVM pristup je dao bolje rezultate nego ANFIS i ANNs kod procjenjivanja dnevne prosječne fluktuacije vodotoka.Stream flow is an important input for hydrology studies because it determines the water variability and magnitude of a river. Water resources engineering always deals with historical data and tries to estimate the forecasting records in order to give a better prediction for any water resources applications, such as designing the water potential of hydroelectric dams, estimating low flow, and maintaining the water supply. This paper presents three soft-computing approaches for dealing with these issues, i.e. artificial neural networks (ANNs), adaptive-neuro-fuzzy inference systems (ANFISs), and support vector machines (SVMs). Telom River, located in the Cameron Highlands district of Pahang, Malaysia, was used in making the estimation. The Telom River’s daily mean discharge records, such as rainfall and river-level data, were used for the period of March 1984 – January 2013 for training, testing, and validating the selected models. The SVM approach provided better results than ANFIS and ANNs in estimating the daily mean fluctuation of the stream’s flow

Development of strain-based fatigue life calculation software for variable amplitude loading data

This thesis presents the development of strain-based fatigue life calculation software for variable amplitude loading data. The main objective of this study is to develop calculation software for fatigue life prediction using MATLAB®. The software allows life predictions to quickly provide fatigue crack initiation using SAESUS data and road loading history on car lower suspension arm. In addition, the fatigue life was predicted using strain life approach subjected to variable amplitude loading. Coffin Manson are the method that provides in the software. Rainflow cycle counting method will be use to extract the cycle from time series data. Then the Palmgren-Rules equation was utilized to calculate cumulative damage. As a result, the GUI will display the result from the method using. From the software development, it can contribute to all user for calculate life prediction especially for variable amplitude loading. Thus the software does not need higher cost and also user friendly

Vibration Analysis of Kenyir Dam Power Station Structure Using a Real Scale 3D Model

In this paper, the vibration analysis in terms of modal and harmonic responses are investigated for the power station structure of Kenyir Dam in Terengganu, Malaysia. Modal analysis is carried out to provide the dynamic characteristics of the power station which includes the natural frequencies and mode shapes. Meanwhile, the harmonic response analysis is performed by applying the force to the structure to obtain the Frequency Response Function (FRF) in certain range of frequencies. A real scale three-dimensional (3D) model of the Kenyir Dam power station is constructed using SolidWorks software and imported to ANSYS software for the Finite Element (FE) analysis. A proper boundary condition is taken into consideration to demonstrate the real behaviour of the power station structure. From the results, six most significant natural frequencies and mode shapes including the FRF in all three axes are selected. The highest natural frequency value occurred at 5.4 Hz with the maximum deflection of 0.90361 m in the z axis direction. This value is important in order to verify whether the structure can overcome the resonance phenomenon from the external disturbance forces in the future

Vibration analysis of Kenyir Dam power station structure using a real scale 3D model

In this paper, the vibration analysis in terms of modal and harmonic responses are investigated for the power station structure of Kenyir Dam in Terengganu, Malaysia. Modal analysis is carried out to provide the dynamic characteristics of the power station which includes the natural frequencies and mode shapes. Meanwhile, the harmonic response analysis is performed by applying the force to the structure to obtain the Frequency Response Function (FRF) in certain range of frequencies. A real scale threedimensional (3D) model of the Kenyir Dam power station is constructed using Solid Works software and imported to ANSYS software for the Finite Element (FE) analysis. A proper boundary condition is taken into consideration to demonstrate the real behaviour of the power station structure. From the results, six most significant natural frequencies and mode shapes including the FRF in all three axes are selected. The highest natural frequency value occurred at 5.4 Hz with the maximum deflection of 0.90361 m in the z axis direction. This value is important in order to verify whether the structure can overcome the resonance phenomenon from the external disturbance forces in the future

Prediction of the Flow-Induced Vibration Response of the Chenderoh Dam Left Bank Section

Flow-induced vibration is a common phenomenon that happened in any of dam structures during the operational condition. This includes the effect of water spilling from the upstream to the downstream of the dam due to high water volume at the upstream side. the release of water from the dam can be beneficial in generating the electricity source to the surrounding areas. However, in some cases, the spill of water can induced the significant vibration effects to the dam structure. In this study, the prediction of the flow-induced vibration response at the left bank section of the real scale Malaysian Chenderoh Dam model is simulated using the ANSYS software. the input force disturbances from the flow of the water at the left bank section during the normal water spilling condition is investigated. the results of frequency domain response and operational defection shapes (ODS) from the effect of flow-induced vibration are compared with the natural frequencies and mode shapes of the dam. From the results, the transient vibration responses due to the flow of water happened at the frequency of 13.3 Hz while the natural frequency of the left bank section occurred at 52.3 Hz, which indicates that there is no resonance phenomenon for the normal case of water spilling at the left bank section of the dam structure. This result is useful for the dam operation section in order to avoid any disaster of the dam structure

Structural Dynamic Analysis of the Chenderoh Dam Sector Gate Section

The dynamic characteristics such as natural frequencies, mode shapes and frequency response function (FRF) are the important characteristics to be investigated to access the level of durability of any dam structures. These characteristics are important since it will be the reference information for any operational methods to be used for the dam structures. In this study, one of the real dam (i.e., Chenderoh Dam) that available in Malaysia is taken into consideration, where the dynamic analysis of the sector gate section of the dam structure is investigated. the real scale of the sector gate section is measured on site and modelled into the CAD software with the consideration of real build-in materials. Then, the finite element (FE) model is constructed in ANSYS software with the required boundary condition and meshing sensitivity analysis. From the result of modal analysis, 30 natural frequencies are determined in the range of 0.5904 Hz to 8.471 Hz together with the mode shapes but only the most significant natural frequencies will be shown in this paper. In addition, all three axes of the FRF graphs show an agreement for the highest natural frequency value at 7.95 Hz, where the maximum deflection occurred in x axis direction with 2.03 × 10-7 m

Environmental management competitive pressure effect on SME environmental innovation activities: A green supply chain perspective

The idea of assimilating green supply chain is to integrate and establish environmental management into the supply chain practices. The study aims to explore how environmental management competitive pressure influences a SME company in Malaysia to incorporate green supply chain integration, which is an efficient platform to develop environmental innovation. This study further advances green supply chain management research in Malaysia by using the method of quantitative analysis to analyze the model developed which data will be collected based on a sample of SMEs in Malaysia in manufacturing sector. The model developed in this study illustrates how environmental management competitive pressure from main competitors affects three fundamental dimensions of green supply chain integration. The research findings suggest that environmental management competitive pressure is a vital driving force for a SME company to incorporate internal and external collaboration in developing green product innovation. From the analysis conducted, the study strongly demonstrated that the best way for a company to counteract competitor’s environmental management success is to first implement strong internal green product development process then move to incorporate external environmental management innovation between their suppliers and customers. The findings also show that internal integration of green product innovation fully mediates the relationship of environmental management competitive pressure and the external integration of green product innovation

A Review of Supply Chain Uncertainty Management in the End-of-Life Vehicle Industry

Various uncertainties exist in the End-of-Life Vehicle (ELV) industry, which further complicates the ELV business’s growth. In order to pursue greater progress in the ELV business establishment, a comprehensive analysis of previous ELV studies with regard to the supply chain uncertainty perspective is essential. The objective of this study is aimed at categorising the existing supply chain uncertainty sources according to their end-of-life (EoL) strategies, identify the management approaches adopted to analyse the prominent research trends, and conduct a regional analysis of ELV supply chain studies for the past years, from 2016 until 2022. The content analysis method was used to extract all the essential information from previous research, and an analysis was performed to obtain the latest research trends and identify the relationship between the gathered data. The findings show that the past research focuses on three main supply chain uncertainties, namely, uncertainty in logistics and network facilities (31.8%), production and operations (30.7%), and environmental (25.0%). Furthermore, the regional analysis shows that 83% of the studies were conducted in developing countries over the past years. Lastly, several research gaps were presented to provide researchers with potential directions and the way forward to explore ELV supply chain research from the uncertainty management context

Preliminary phytochemical screening of eurycomanone for selection of high quality planting materials: Eurycoma longifolia

Eurycoma longifolia has been widely used in traditional herbal preparation and presently there are many commercial products available for general health and libido. However, study on plant breeding of this species is still in its infancy. Thus, Forest Research Institute Malaysia (FRIM) has taken an initiative to conduct provenance trial of this species in order to select the best provenance and eurycomanone is chosen as bioactive marker. The aim of this study was to analyze the percentage of eurycomanone extracted from root, stem and leaves parts of E. longifolia from different provenances collected throughout Peninsular Malaysia. The eurycomanone compound is extracted with pure water and the present is detected by Ultra Performance Liquid Chromatography (UPLC). Findings showed that the highest percentage of eurycomanone present in the root extract of Terengganu with 1.46% while the lowest is Melaka with 0.17%. Stem part of the plant showed there was presence of eurycomanone compound relatively in small percentage except for Terengganu, while there was no eurycomanone compound detected in leaves extract from all provenances tested (Johor, Kedah/Perlis, Melaka, Pahang, Perak, Pulau Pinang, Selangor and Terengganu). However, it is still too early to derive any conclusion on the best provenance based on chemical marker itself