Search results for: high performance.
2977 Additional Considerations on a Sequential Life Testing Approach using a Weibull Model
Authors: D. I. De Souza, D. R. Fonseca, R. Rocha
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In this paper we will develop further the sequential life test approach presented in a previous article by [1] using an underlying two parameter Weibull sampling distribution. The minimum life will be considered equal to zero. We will again provide rules for making one of the three possible decisions as each observation becomes available; that is: accept the null hypothesis H0; reject the null hypothesis H0; or obtain additional information by making another observation. The product being analyzed is a new type of a low alloy-high strength steel product. To estimate the shape and the scale parameters of the underlying Weibull model we will use a maximum likelihood approach for censored failure data. A new example will further develop the proposed sequential life testing approach.Keywords: Sequential Life Testing, Underlying Weibull Model, Maximum Likelihood Approach, Hypothesis Testing.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 13942976 Subjective Evaluation of Spectral and Time Domain Cascading Algorithm for Speech Enhancement for Mobile Communication
Authors: Harish Chander, Balwinder Singh, Ravinder Khanna
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In this paper, we present the comparative subjective analysis of Improved Minima Controlled Recursive Averaging (IMCRA) Algorithm, the Kalman filter and the cascading of IMCRA and Kalman filter algorithms. Performance of speech enhancement algorithms can be predicted in two different ways. One is the objective method of evaluation in which the speech quality parameters are predicted computationally. The second is a subjective listening test in which the processed speech signal is subjected to the listeners who judge the quality of speech on certain parameters. The comparative objective evaluation of these algorithms was analyzed in terms of Global SNR, Segmental SNR and Perceptual Evaluation of Speech Quality (PESQ) by the authors and it was reported that with cascaded algorithms there is a substantial increase in objective parameters. Since subjective evaluation is the real test to judge the quality of speech enhancement algorithms, the authenticity of superiority of cascaded algorithms over individual IMCRA and Kalman algorithms is tested through subjective analysis in this paper. The results of subjective listening tests have confirmed that the cascaded algorithms perform better under all types of noise conditions.
Keywords: Speech enhancement, spectral domain, time domain, PESQ, subjective analysis, objective analysis.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 12372975 Illicit Return Practices of Irregular Migrants from Greece to Turkey
Authors: Enkelejda Koka, Denard Veshi
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Since 2011, in the name of ‘humanitarianism’ and deaths in the Mediterranean Sea, the legal and political justification delivered by Greece to manage the refugee crisis is pre-emptive interception. Although part of the EU, Greece adopted its own strategy. These practices have also created high risks for migrants generally resulting in non-rescue episodes and push-back practices having lethal consequences to the life of the irregular migrant. Thus, this article provides an analysis of the Greek ‘compassionate border work’ policy, a practice known as push-back. It is argued that these push-back practices violate international obligations, notably the ‘right to life’, the ‘duty to search and rescue’, the prohibition of inhuman or degrading treatment or punishment and the principle of non-refoulement.
Keywords: Greece, migrants, push-back policy, violation of international law.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 10662974 Enhanced Weighted Centroid Localization Algorithm for Indoor Environments
Authors: I. Nižetić Kosović, T. Jagušt
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Lately, with the increasing number of location-based applications, demand for highly accurate and reliable indoor localization became urgent. This is a challenging problem, due to the measurement variance which is the consequence of various factors like obstacles, equipment properties and environmental changes in complex nature of indoor environments. In this paper we propose low-cost custom-setup infrastructure solution and localization algorithm based on the Weighted Centroid Localization (WCL) method. Localization accuracy is increased by several enhancements: calibration of RSSI values gained from wireless nodes, repetitive measurements of RSSI to exclude deviating values from the position estimation, and by considering orientation of the device according to the wireless nodes. We conducted several experiments to evaluate the proposed algorithm. High accuracy of ~1m was achieved.
Keywords: Indoor environment, received signal strength indicator, weighted centroid localization, wireless localization.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 31092973 Feature's Extraction of Human Body Composition in Images by Segmentation Method
Authors: Mousa Mojarrad, Mashallah Abbasi Dezfouli, Amir Masoud Rahmani
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Detection and recognition of the Human Body Composition and extraction their measures (width and length of human body) in images are a major issue in detecting objects and the important field in Image, Signal and Vision Computing in recent years. Finding people and extraction their features in Images are particularly important problem of object recognition, because people can have high variability in the appearance. This variability may be due to the configuration of a person (e.g., standing vs. sitting vs. jogging), the pose (e.g. frontal vs. lateral view), clothing, and variations in illumination. In this study, first, Human Body is being recognized in image then the measures of Human Body extract from the image.
Keywords: Analysis of image processing, canny edge detection, classification, feature extraction, human body recognition, segmentation.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 27812972 A Simple Electronic Curvy Length Measurement System: Application to Geography
Authors: Arijit Roy, Sharmistha Roy, Dibyendu Chatterjee
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This article describes an interesting and inexpensive laboratory experiment for undergraduate students of electronics, geography and related disciplines. The objective of the proposed experiment is to improve the students’ exposure on the basic principles of instrumentation and to demonstrate an electronic measurement system. A simple electronic curvy length measurement system is presented here. Such a system can be used to measure curvy lengths e.g. length of a river, road or railway line etc. from topographical map. The proposed system is composed of simple functional blocks which are usually demonstrated in laboratory or in theory course of electronics at the undergraduate level. The experiment is assigned to a group of students and it is found that the experiment can fulfill its objectives with high degree of satisfaction.
Keywords: Curvy length measurement, Education, Electronics, Laboratory experiment, Topographical map.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 23332971 A New Precautionary Method for Measurement and Improvement the Data Quality
Authors: Seyed Mohammad Hossein Moossavizadeh, Mehran Mohsenzadeh, Nasrin Arshadi
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the data quality is a kind of complex and unstructured concept, which is concerned by information systems managers. The reason of this attention is the high amount of Expenses for maintenance and cleaning of the inefficient data. Such a data more than its expenses of lack of quality, cause wrong statistics, analysis and decisions in organizations. Therefor the managers intend to improve the quality of their information systems' data. One of the basic subjects of quality improvement is the evaluation of the amount of it. In this paper, we present a precautionary method, which with its application the data of information systems would have a better quality. Our method would cover different dimensions of data quality; therefor it has necessary integrity. The presented method has tested on three dimensions of accuracy, value-added and believability and the results confirm the improvement and integrity of this method.
Keywords: Data quality, precaution, information system, measurement, improvement.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 14732970 Navigation of Multiple Mobile Robots using Rule-based-Neuro-Fuzzy Technique
Authors: Saroj Kumar Pradhan, Dayal Ramakrushna Parhi, Anup Kumar Panda
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This paper deals with motion planning of multiple mobile robots. Mobile robots working together to achieve several objectives have many advantages over single robot system. However, the planning and coordination between the mobile robots is extremely difficult. In the present investigation rule-based and rulebased- neuro-fuzzy techniques are analyzed for multiple mobile robots navigation in an unknown or partially known environment. The final aims of the robots are to reach some pre-defined goals. Based upon a reference motion, direction; distances between the robots and obstacles; and distances between the robots and targets; different types of rules are taken heuristically and refined later to find the steering angle. The control system combines a repelling influence related to the distance between robots and nearby obstacles and with an attracting influence between the robots and targets. Then a hybrid rule-based-neuro-fuzzy technique is analysed to find the steering angle of the robots. Simulation results show that the proposed rulebased- neuro-fuzzy technique can improve navigation performance in complex and unknown environments compared to this simple rulebased technique.Keywords: Mobile robots, Navigation, Neuro-fuzzy, Obstacle avoidance, Rule-based, Target seeking
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18022969 Analyzing The Effect of Variable Round Time for Clustering Approach in Wireless Sensor Networks
Authors: Vipin Pal, Girdhari Singh, R P Yadav
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As wireless sensor networks are energy constraint networks so energy efficiency of sensor nodes is the main design issue. Clustering of nodes is an energy efficient approach. It prolongs the lifetime of wireless sensor networks by avoiding long distance communication. Clustering algorithms operate in rounds. Performance of clustering algorithm depends upon the round time. A large round time consumes more energy of cluster heads while a small round time causes frequent re-clustering. So existing clustering algorithms apply a trade off to round time and calculate it from the initial parameters of networks. But it is not appropriate to use initial parameters based round time value throughout the network lifetime because wireless sensor networks are dynamic in nature (nodes can be added to the network or some nodes go out of energy). In this paper a variable round time approach is proposed that calculates round time depending upon the number of active nodes remaining in the field. The proposed approach makes the clustering algorithm adaptive to network dynamics. For simulation the approach is implemented with LEACH in NS-2 and the results show that there is 6% increase in network lifetime, 7% increase in 50% node death time and 5% improvement over the data units gathered at the base station.Keywords: Wireless Sensor Network, Clustering, Energy Efficiency, Round Time.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 17942968 Fracture Location Characterizations of Dissimilar Friction Stir Welds
Authors: Esther T. Akinlabi, Stephen A. Akinlabi
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This paper reports the tensile fracture location characterizations of dissimilar friction stir welds between 5754 aluminium alloy and C11000 copper. The welds were produced using three shoulder diameter tools; namely, 15, 18 and 25 mm by varying the process parameters. The rotational speeds considered were 600, 950 and 1200 rpm while the feed rates employed were 50, 150 and 300 mm/min to represent the low, medium and high settings respectively. The tensile fracture locations were evaluated using the optical microscope to identify the fracture locations and were characterized. It was observed that 70% of the tensile samples failed in the Thermo Mechanically Affected Zone (TMAZ) of copper at the weld joints. Further evaluation of the fracture surfaces of the pulled tensile samples revealed that welds with low Ultimate Tensile Strength either have defects or intermetallics present at their joint interfaces.Keywords: fracture location, friction stir welding, intermetallics, metallography,
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 19752967 Enhancing Word Meaning Retrieval Using FastText and NLP Techniques
Authors: Sankalp Devanand, Prateek Agasimani, V. S. Shamith, Rohith Neeraje
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Machine translation has witnessed significant advancements in recent years, but the translation of languages with distinct linguistic characteristics, such as English and Sanskrit, remains a challenging task. This research presents the development of a dedicated English to Sanskrit machine translation model, aiming to bridge the linguistic and cultural gap between these two languages. Using a variety of natural language processing (NLP) approaches including FastText embeddings, this research proposes a thorough method to improve word meaning retrieval. Data preparation, part-of-speech tagging, dictionary searches, and transliteration are all included in the methodology. The study also addresses the implementation of an interpreter pattern and uses a word similarity task to assess the quality of word embeddings. The experimental outcomes show how the suggested approach may be used to enhance word meaning retrieval tasks with greater efficacy, accuracy, and adaptability. Evaluation of the model's performance is conducted through rigorous testing, comparing its output against existing machine translation systems. The assessment includes quantitative metrics such as BLEU scores, METEOR scores, Jaccard Similarity etc.
Keywords: Machine translation, English to Sanskrit, natural language processing, word meaning retrieval, FastText embeddings.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1562966 Fragility Assessment for Vertically Irregular Buildings with Soft Storey
Authors: N. Akhavan, Sh. Tavousi Tafreshi, A. Ghasemi
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Seismic behavior of irregular structures through the past decades indicate that the stated buildings do not have appropriate performance. Among these subjects, the current paper has investigated the behavior of special steel moment frame with different configuration of soft storey vertically. The analyzing procedure has been evaluated with respect to incremental dynamic analysis (IDA), and numeric process was carried out by OpenSees finite element analysis package. To this end, nine 2D steel frames, with different numbers of stories and irregularity positions, which were subjected to seven pairs of ground motion records orthogonally with respect to Ibarra-Krawinkler deterioration model, have been investigated. This paper aims at evaluating the response of two-dimensional buildings incorporating soft storey which subjected to bi-directional seismic excitation. The IDAs were implemented for different stages of PGA with various ground motion records, in order to determine maximum inter-storey drift ratio. According to statistical elements and fracture range (standard deviation), the vulnerability or exceedance from above-mentioned cases has been examined. For this reason, fragility curves for different placement of soft storey in the first, middle and the last floor for 4, 8, and 16 storey buildings have been generated and compared properly.
Keywords: Special steel moment frame, soft storey, incremental dynamic analysis, fragility curve.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 14862965 A Survey on MAC Protocols for Vehicular Ad-Hoc Networks
Authors: B. Cynthia Sherin, E. A. Mary Anita
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Vehicular Ad-hoc Network (VANET) is an emerging and very promising technology that has great demand on the access capability of the existing wireless technology. VANETs help improve traffic safety and efficiency. Each vehicle can exchange their information to inform the other vehicles about the current status of the traffic flow or a dangerous situation such as an accident. To achieve these, a reliable and efficient Medium Access Control (MAC) protocol with minimal transmission collisions is required. High speed nodes, absence of infrastructure, variations in topology and their QoS requirements makes it difficult for designing a MAC protocol in vehicular networks. There are several MAC protocols proposed for VANETs to ensure that all the vehicles could send safety messages without collisions by reducing the end-to-end delay and packet loss ratio. This paper gives an overview of the several proposed MAC protocols for VANETs along with their benefits and limitations and presents an overall classification based on their characteristics.
Keywords: MAC Protocols, QoS, VANET, V2V, V2I.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 9522964 Analyzing of Temperature-Dependent Thermal Conductivity Effect in the Numerical Modeling of Fin-Tube Radiators: Introduction of a New Method
Authors: Farzad Bazdidi-Tehrani, Mohammad Hadi Kamrava
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In all industries which are related to heat, suitable thermal ranges are defined for each device to operate well. Consideration of these limits requires a thermal control unit beside the main system. The Satellite Thermal Control Unit exploits from different methods and facilities individually or mixed. For enhancing heat transfer between primary surface and the environment, utilization of radiating extended surfaces are common. Especially for large temperature differences; variable thermal conductivity has a strong effect on performance of such a surface .In most literatures, thermo-physical properties, such as thermal conductivity, are assumed as constant. However, in some recent researches the variation of these parameters is considered. This may be helpful for the evaluation of fin-s temperature distribution in relatively large temperature differences. A new method is introduced to evaluate temperature-dependent thermal conductivity values. The finite volume method is employed to simulate numerically the temperature distribution in a space radiating fin. The present modeling is carried out for Aluminum as fin material and compared with previous method. The present results are also compared with those of two other analytical methods and good agreement is shown.Keywords: Variable thermal conductivity, New method, Finitevolume method, Combined heat transfer, Extended Surface
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 23352963 A Matching Algorithm of Minutiae for Real Time Fingerprint Identification System
Authors: Shahram Mohammadi, Ali Frajzadeh
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A lot of matching algorithms with different characteristics have been introduced in recent years. For real time systems these algorithms are usually based on minutiae features. In this paper we introduce a novel approach for feature extraction in which the extracted features are independent of shift and rotation of the fingerprint and at the meantime the matching operation is performed much more easily and with higher speed and accuracy. In this new approach first for any fingerprint a reference point and a reference orientation is determined and then based on this information features are converted into polar coordinates. Due to high speed and accuracy of this approach and small volume of extracted features and easily execution of matching operation this approach is the most appropriate for real time applications.
Keywords: Matching, Minutiae, Reference point, Reference orientation
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 24202962 Digital Cinema Watermarking State of Art and Comparison
Authors: H. Kelkoul, Y. Zaz
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Nowadays, the vigorous popularity of video processing techniques has resulted in an explosive growth of multimedia data illegal use. So, watermarking security has received much more attention. The purpose of this paper is to explore some watermarking techniques in order to observe their specificities and select the finest methods to apply in digital cinema domain against movie piracy by creating an invisible watermark that includes the date, time and the place where the hacking was done. We have studied three principal watermarking techniques in the frequency domain: Spread spectrum, Wavelet transform domain and finally the digital cinema watermarking transform domain. In this paper, a detailed technique is presented where embedding is performed using direct sequence spread spectrum technique in DWT transform domain. Experiment results shows that the algorithm provides high robustness and good imperceptibility.Keywords: Digital cinema, watermarking, wavelet, spread spectrum, JPEG2000.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 11942961 TiO2 Nanowires as Efficient Heterogeneous Photocatalysts for Waste-Water Treatment
Authors: Gul Afreen, Sreedevi Upadhyayula, Mahendra K. Sunkara
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One-dimensional (1D) nanostructures like nanowires, nanotubes, and nanorods find variety of practical application owing to their unique physico-chemical properties. In this work, TiO2 nanowires were synthesized by direct oxidation of titanium particles in a unique microwave plasma jet reactor. The prepared TiO2 nanowires manifested the flexible features, and were characterized by using X-ray diffraction, Brunauer-Emmett-Teller (BET) surface area analyzer, UV-Visible and FTIR spectrophotometers, Scanning electron microscope, and Transmission electron microscope. Further, the photodegradation efficiency of these nanowires were tested against toxic organic dye like methylene blue (MB) and the results were compared with the commercial TiO2. It was found that TiO2 nanowires exhibited superior photocatalytic performance (89%) as compared to commercial TiO2 (75%) after 60 min of reaction. This is attributed to the lower recombination rate and increased interfacial charge transfer in TiO2 nanowire. Pseudo-first order kinetic modelling performed with the experimental results revealed that the rate constant of photodegradation in case of TiO2 nanowire was 1.3 times higher than that of commercial TiO2. Superoxide radical (O2˙−) was found to be the major contributor in the photodegradation mechanism. Based on the trapping experiments, a plausible mechanism of the photocatalytic reaction is discussed.
Keywords: Heterogeneous catalysis, photodegradation, reactive oxygen species, TiO2 nanowires.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 9072960 Design and Fabrication of a Scaffold with Appropriate Features for Cartilage Tissue Engineering
Authors: S. S. Salehi, A. Shamloo
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Poor ability of cartilage tissue when experiencing a damage leads scientists to use tissue engineering as a reliable and effective method for regenerating or replacing damaged tissues. An artificial tissue should have some features such as biocompatibility, biodegradation and, enough mechanical properties like the original tissue. In this work, a composite hydrogel is prepared by using natural and synthetic materials that has high porosity. Mechanical properties of different combinations of polymers such as modulus of elasticity were tested, and a hydrogel with good mechanical properties was selected. Bone marrow derived mesenchymal stem cells were also seeded into the pores of the sponge, and the results showed the adhesion and proliferation of cells within the hydrogel after one month. In comparison with previous works, this study offers a new and efficient procedure for the fabrication of cartilage like tissue and further cartilage repair.Keywords: Cartilage tissue engineering, hydrogel, mechanical strength, mesenchymal stem cell.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 13002959 Foundation Retrofitting of Storage Tank under Seismic Load
Authors: Seyed Abolhasan Naeini, Mohammad Hossein Zade, E. Izadi, M. Hossein Zade
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The different seismic behavior of liquid storage tanks rather than conventional structures makes their responses more complicated. Uplifting and excessive settlement due to liquid sloshing are the most frequent damages in cylindrical liquid tanks after shell bucking failure modes. As a matter of fact, uses of liquid storage tanks because of the simple construction on compact layer of soil as a foundation are very conventional, but in some cases need to retrofit are essential. The tank seismic behavior can be improved by modifying dynamic characteristic of tank with verifying seismic loads as well as retrofitting and improving base ground. This paper focuses on a typical steel tank on loose, medium and stiff sandy soil and describes an evaluation of displacement of the tank before and after retrofitting. The Abaqus program was selected for its ability to include shell and structural steel elements, soil-structure interaction, and geometrical nonlinearities and contact type elements. The result shows considerable decreasing in settlement and uplifting in the case of retrofitted tank. Also, by increasing shear strength parameter of soil, the performance of the liquid storage tank under the case of seismic load increased.Keywords: Steel tank, soil-structure, sandy soil, seismic load.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 16232958 A Discrete Filtering Algorithm for Impulse Wave Parameter Estimation
Authors: Khaled M. EL-Naggar
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This paper presents a new method for estimating the mean curve of impulse voltage waveforms that are recorded during impulse tests. In practice, these waveforms are distorted by noise, oscillations and overshoot. The problem is formulated as an estimation problem. Estimation of the current signal parameters is achieved using a fast and accurate technique. The method is based on discrete dynamic filtering algorithm (DDF). The main advantage of the proposed technique is its ability in producing the estimates in a very short time and at a very high degree of accuracy. The algorithm uses sets of digital samples of the recorded impulse waveform. The proposed technique has been tested using simulated data of practical waveforms. Effects of number of samples and data window size are studied. Results are reported and discussed.
Keywords: Digital Filtering, Estimation, Impulse wave, Stochastic filtering.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18552957 Islam in the Context of Political Processes in Modern Kazakhstan
Authors: Duissenbayeva Albina, Rysbekova Shamshiya, Borbassova Karlygash
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Religion revival including Islam in Kazakhstan represents reaction, first of all on internal social and political change, events after disintegration of the USSR. Process of revival of Kazakhstan Islam was accompanied as positive, so by negative tendencies. Old mosques were restored, were under construction new, Islamic schools and high schools were created, was widely studied religious the dogmatic person, the corresponding literature was published, expanded contacts with foreign Muslim brothers in the faith, the centers of the Arab-Muslim culture extended. At the same time in Kazakhstan, there are religious-political parties and movements, pursuing radical goals down to change the spiritual and cultural identity of Muslims of Kazakhstan by the forcible introduction of non-traditional religious and political, ethnic and cultural values.
Keywords: Terrorist act, Islamic factor, national tasks, radical Islam, the role of Islam.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 22522956 Solving Process Planning and Scheduling with Number of Operation Plus Processing Time Due-Date Assignment Concurrently Using a Genetic Search
Authors: Halil Ibrahim Demir, Alper Goksu, Onur Canpolat, Caner Erden, Melek Nur
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Traditionally process planning, scheduling and due date assignment are performed sequentially and separately. High interrelation between these functions makes integration very useful. Although there are numerous works on integrated process planning and scheduling and many works on scheduling with due date assignment, there are only a few works on the integration of these three functions. Here we tested the different integration levels of these three functions and found a fully integrated version as the best. We applied genetic search and random search and genetic search was found better compared to the random search. We penalized all earliness, tardiness and due date related costs. Since all these three terms are all undesired, it is better to penalize all of them.Keywords: Process planning, scheduling, due-date assignment, genetic algorithm, random search.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 8442955 Diagnosing the Cause and its Timing of Changes in Multivariate Process Mean Vector from Quality Control Charts using Artificial Neural Network
Authors: Farzaneh Ahmadzadeh
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Quality control charts are very effective in detecting out of control signals but when a control chart signals an out of control condition of the process mean, searching for a special cause in the vicinity of the signal time would not always lead to prompt identification of the source(s) of the out of control condition as the change point in the process parameter(s) is usually different from the signal time. It is very important to manufacturer to determine at what point and which parameters in the past caused the signal. Early warning of process change would expedite the search for the special causes and enhance quality at lower cost. In this paper the quality variables under investigation are assumed to follow a multivariate normal distribution with known means and variance-covariance matrix and the process means after one step change remain at the new level until the special cause is being identified and removed, also it is supposed that only one variable could be changed at the same time. This research applies artificial neural network (ANN) to identify the time the change occurred and the parameter which caused the change or shift. The performance of the approach was assessed through a computer simulation experiment. The results show that neural network performs effectively and equally well for the whole shift magnitude which has been considered.Keywords: Artificial neural network, change point estimation, monte carlo simulation, multivariate exponentially weighted movingaverage
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 13872954 Intelligent Temperature Controller for Water-Bath System
Authors: Om Prakash Verma, Rajesh Singla, Rajesh Kumar
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Conventional controller’s usually required a prior knowledge of mathematical modelling of the process. The inaccuracy of mathematical modelling degrades the performance of the process, especially for non-linear and complex control problem. The process used is Water-Bath system, which is most widely used and nonlinear to some extent. For Water-Bath system, it is necessary to attain desired temperature within a specified period of time to avoid the overshoot and absolute error, with better temperature tracking capability, else the process is disturbed.
To overcome above difficulties intelligent controllers, Fuzzy Logic (FL) and Adaptive Neuro-Fuzzy Inference System (ANFIS), are proposed in this paper. The Fuzzy controller is designed to work with knowledge in the form of linguistic control rules. But the translation of these linguistic rules into the framework of fuzzy set theory depends on the choice of certain parameters, for which no formal method is known. To design ANFIS, Fuzzy-Inference-System is combined with learning capability of Neural-Network.
It is analyzed that ANFIS is best suitable for adaptive temperature control of above system. As compared to PID and FLC, ANFIS produces a stable control signal. It has much better temperature tracking capability with almost zero overshoot and minimum absolute error.
Keywords: PID Controller, FLC, ANFIS, Non-Linear Control System, Water-Bath System, MATLAB-7.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 55632953 Corporate Governance, Shareholder Monitoring and Cost of Debt in Malaysia
Authors: Zulkufly Ramly
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This paper attempts to investigate the effect of corporate governance and shareholder monitoring mechanisms on cost of debt of Malaysian listed firms. We assess the quality of corporate governance using comprehensive corporate governance index, which consists of 139 items in six broad categories. We classify shareholder monitoring mechanisms into concentrated ownership, family, insider and government ownerships. Using panel sample from 2003 to 2007, regression results show that high corporate governance quality and concentrated ownership lower firm cost of debt. Debt issuers consider board structure and procedures, board compensation practices, accountability and audit, transparency and social and environmental activities as integral components of a good corporate governance framework.
Keywords: Corporate governance index, cost of debt, ownership structure, Malaysia.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 35192952 Interfacial Layer Effect on Novel p-Ni1-xO:Li/n-Si Heterojunction Solar Cells
Authors: Feng-Hao Hsu, Na-Fu Wang, Yu-Zen Tsai, Yu-Song Cheng, Cheng-Fu Yang, Mau-Phon Houng
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This study fabricates p-type Ni1−xO:Li/n-Si heterojunction solar cells (P+/n HJSCs) by using radio frequency (RF) magnetron sputtering and investigates the effect of substrate temperature on photovoltaic cell properties. Grazing incidence x-ray diffraction, four point probe, and ultraviolet-visible-near infrared discover the optoelectrical properties of p-Ni1-xO thin films. The results show that p-Ni1-xO thin films deposited at 300 oC has the highest grain size (22.4 nm), average visible transmittance (~42%), and electrical resistivity (2.7 Ωcm). However, the conversion efficiency of cell is shown only 2.33% which is lower than the cell (3.39%) fabricated at room temperature. This result can be mainly attributed to interfacial layer thickness (SiOx) reduces from 2.35 nm to 1.70 nm, as verified by high-resolution transmission electron microscopy.
Keywords: Heterojunction, nickel oxide, solar cells, sputtering.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18602951 Stress Variation of Underground Building Structure during Top-Down Construction
Authors: Soo-yeon Seo, Seol-ki Kim, Su-jin Jung
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In the construction of a building, it is necessary to minimize construction period and secure enough work space for stacking of materials during the construction especially in city area. In this manner, various top-down construction methods have been developed and widely used in Korea. This paper investigates the stress variation of underground structure of a building constructed by using SPS (Strut as Permanent System) known as a top-down method in Korea through an analytical approach. Various types of earth pressure distribution related to ground condition were considered in the structural analysis of an example structure at each step of the excavation. From the analysis, the most high member force acting on beams was found when the ground type was medium sandy soil and a stress concentration was found in corner area.Keywords: Construction of building, top-down construction method, earth pressure distribution, member force, stress concentration.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 17262950 Mechanical and Chemical Reliability Assessment of Silica Optical Fibres
Authors: Irina Severin, M. Caramihai, K. Chung, G. Tasca, T. Park
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The current study has investigated the ageing phenomena of silica optical fibres in relation to water activity which might be accelerated when exposed to a supplementary energy, such as microwaves. A controlled stress by winding fibres onto accurate diameter mandrel was applied. Taking into account that normally a decrease in fibre strength is induced in time by chemical action of water, the effects of cumulative reagents such as: water, applied stress and supplementary energy (microwave) in some cases acted in the opposite manner. The microwave effect as a structural relaxation catalyst appears unexpected, even if the overall gain in fibre strength is not high, but the stress corrosion factor revealed significant increase in certain simulation conditions.Keywords: optical fibres, mechanical testing, aging, microwave, structural relaxation.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 16342949 Effect of Impurities in the Chlorination Process of TiO2
Authors: Seok Hong Min, Tae Kwon Ha
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With the increasing interest on Ti alloys, the extraction process of Ti from its typical ore, TiO2, has long been and will be important issue. As an intermediate product for the production of pigment or titanium metal sponge, tetrachloride (TiCl4) is produced by fluidized bed using high TiO2 feedstock. The purity of TiCl4 after chlorination is subjected to the quality of the titanium feedstock. Since the impurities in the TiCl4 product are reported to final products, the purification process of the crude TiCl4 is required. The purification process includes fractional distillation and chemical treatment, which depends on the nature of the impurities present and the required quality of the final product. In this study, thermodynamic analysis on the impurity effect in the chlorination process, which is the first step of extraction of Ti from TiO2, has been conducted. All thermodynamic calculations were performed using the FactSage thermodynamical software.Keywords: Rutile, titanium, chlorination process, impurities, thermodynamic calculation, FactSage.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 17062948 Classifier Based Text Mining for Neural Network
Authors: M. Govindarajan, R. M. Chandrasekaran
Abstract:
Text Mining is around applying knowledge discovery techniques to unstructured text is termed knowledge discovery in text (KDT), or Text data mining or Text Mining. In Neural Network that address classification problems, training set, testing set, learning rate are considered as key tasks. That is collection of input/output patterns that are used to train the network and used to assess the network performance, set the rate of adjustments. This paper describes a proposed back propagation neural net classifier that performs cross validation for original Neural Network. In order to reduce the optimization of classification accuracy, training time. The feasibility the benefits of the proposed approach are demonstrated by means of five data sets like contact-lenses, cpu, weather symbolic, Weather, labor-nega-data. It is shown that , compared to exiting neural network, the training time is reduced by more than 10 times faster when the dataset is larger than CPU or the network has many hidden units while accuracy ('percent correct') was the same for all datasets but contact-lences, which is the only one with missing attributes. For contact-lences the accuracy with Proposed Neural Network was in average around 0.3 % less than with the original Neural Network. This algorithm is independent of specify data sets so that many ideas and solutions can be transferred to other classifier paradigms.Keywords: Back propagation, classification accuracy, textmining, time complexity.
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