Earlier publications indicate that Polytetrafluoroethylene (PTFE)-faced hydrodynamic tilting pad thrust bearings have been successfully designed and applied in large hydro generators in the former Soviet-Union, China, Japan and the UK. The properties of PTFE such as corrosion resistance, anti-seizure characteristics, embeddability, and lower coefficient of friction are found to be much superior to Babbitt’s and it has been recommended by many researchers that the Babbitt-lined bearings could be replaced advantageously by PTFE. In view of this, an analytical study has been made in this present paper to compare the performance between conventional Babbitt-lined tilting pad thrust bearings with PTFE-faced bearings under identical operating conditions. Performance characteristics of both these bearings are analytically studied by solving the Governing equations by suitable numerical methods. The results indicated many advantages in the application of PTFE-faced bearings showing low operating temperature, low power loss, higher load carrying capacity as compared to Babbitt lined bearings.

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Structural analysis of interaction of foundation slab with subsoil represented by elastic half space can be performed by various numerical methods. Verification of 2D simplified FEA approach incorporating numerical integration of the Boussinesq solution is emphasized in this paper by direct comparison with 3D FEA, which uses semi-infinite elements. Both methods were used to solve two numerical examples and the result are presented and compared in this study. Paper also includes discussion of capabilities of both approaches with their advantages and disadvantages.

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In the traditional variables control charts, the sample observations are characterized by numerical values. In practice, the uncertainty that comes from the measurement system; including operators, gauges, and environmental conditions, results in linguistic data and thereby fuzzy control charts. In this situation, fuzzy set theory is a useful tool to handle this ambiguity. Therefore, this research develops variables control charts for monitoring process mean and variability under linguistic data using fuzzy logic. In this research, the each observation is represented by a triangular membership function. Then, the comprehensive output measure (COM) is obtained for each sample replicate using fuzzy logic. Finally, the COM values of sample replicates are utilized to establish the appropriate variable control chart. Similarly, each process capability index is represented by a suitable membership function and then estimated using fuzzy logic to assess process capability. This approach was implemented on three case studies; in all of which the developed control charts and estimated process capability were found efficient in monitoring of process condition and assessing its performance. Moreover, the simplicity and ease of interpretation can make this approach be widely used by practitioners. In conclusions, the developed variables control charts and process capability indices may provide a beneficial guide for practitioners in monitoring process parameters and its performance in a wide range of manufacturing applications under linguistic data.

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A two-dimensional mathematical model was developed to simulate the flow system at the upper aquifer of the quaternary sediments. The proposed conceptual model is fixed to one layer, meaning that the activity of the deeper aquifer is negligible. Twenty soil samples are selected to obtain the soil texture classes. The average values of minimum infiltration rates are interpolated using Kriging techniques in Geostatistical analysis extension of Arc GIS 9.3 to create the soil hydrologic group layer. Based on the covered area by soil hydrologic groups, the initial values of hydraulic conductivity and specific yield are supplied to the numerical program. According to the calibration process, the hydraulic characteristics of the upper aquifer has been identified, the hydraulic conductivity in the study area ranged (1-10) m/day, while the specific yield ranges between (0.1- 0.4). Two management cases (fixed well location and moving well location) were considered by executing the model with adopting calibrated parameters by using tabu search (TS) technique. The choice option for the moving well location in the second case leads to an increase of 9% in the total pumping rates compared to fixed well location. The results were compared with another study conducted for the same study area using genetic algorithms (GA) technique. It can be concluded that TS technique yields better results than GA technique.

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The research on Chipless RFID is getting popular everyday due to its ease of construction and cheap manufacturing. However, the existing dimensions reported in the open literature are still too large and the detection techniques are also complex in nature. In this paper, a new passive UWB tag structure and a corresponding relatively simple detection technique have been proposed. The structure contains a number of slots inserted in a planar circular disk. Two different tags have been designed and simulated, the first with one slot and the second with five different slots. Taconic TLX-8 has been chosen as the substrate material of structure having a dielectric constant of 2.55 and 0.5mm of height. The backscattering information from the tag has been utilized for the detection of the tag bits on board. The tag structure justification has been done by the surface current response and the detection method is employed to extract the bits. A good agreement has been found in the simulation. For five bit system, bit ‘10000’ and bit ‘11111’ have been successfully extracted. This will motivate RFID researchers to employ more bits on the tag and will provide the encoding the bits with ease.

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This research proposes a multivariate Fuzzy Hotelling T2 control chart for monitoring linguistic quality characteristics. The main idea is to find a defuzzified “COM” value using the Fuzzy Inference System representing the fuzzy data in a Triangular membership function as one output. The “COM” values are then utilized to construct the control charts. Moreover, ? cut levels are also applied to investigate the tightness of the inspection on any quality control process. Three case studies were investigated (Frozen Food example, porcelain process, and Pharmaceutical Quality Metrics). Results showed that the proposed Fuzzy Hotelling T2 control chart is found efficient in dealing with sensitive processes require small shifts monitoring. In conclusion, the proposed approach shall provide a beneficial guide for practitioners in the development of control charts and process capability indices.

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This article proposes the design of a compact beveled rectangular planar monopole antenna for Ultra wideband (UWB) applications. The radiating element is printed on a low- cost FR-4 epoxy substrate with relative permittivity of 4.4 and thickness of 1.6mm. It has overall dimensions of 18×15×1.6 mm3. A 50-ohm coplanar waveguide (CPW) transmission line is used to excite the proposed antenna. The simulated impedance bandwidth of the proposed antenna for -10dB reflection coefficient is from 2.9GHz to more than 12GHz. Radiation efficiency better than 90% and group delay variation less than 1ns are obtained throughout the UWB. Furthermore, a stable omni directional radiation and a peak gain of 3.91dB are observed. A prototype of the proposed antenna is fabricated. The measured reflection coefficient of the proposed antenna covers a wide impedance bandwidth from 2GHz to over 12GHz with S11 better than -10dB.

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The main aim of the present work is to develop a valid empirical equation which can be used to determine the ultimate strength of the simply supported thin square plates (of common size 500×500 mm with variable plate thickness) having both initial imperfections and local geometric imperfections namely dent. Both the dent parameters (namely Dent Length (DL), Dent Aspect Ratio (DAR), Dent Depth (DD) and Dent Angle of Orientation (DAO)) and shell parameters (namely Slenderness Ratio (SLR) which accounts for both plate thickness and amplitude of half wave sinusoidal shape initial imperfections) are accounted to determine the ultimate strength of the dented thin square plates. By varying these parameters 2025 FE dented plate models (with a center dent) are generated and analyzed using non-linear FE analysis of ANSYS including both material and geometrical non-linearities to determine the ultimate strength of the dented plates. Using these ultimate strengths and coded input parameters of FE models, a valid response surface regression model-an empirical model is developed. The input parameters are coded to overcome the effect of different units of input parameters and their range.

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In this study, properties of a normal and three types of super plasticized concretes produced are characterized. In the process the effects of equally combined coarse aggregates gradation of 12.5 mm and 19 mm were investigated. The normal concrete tagged E0 with 0.4 water cement ratio (w/c) of a 1:2:3 mix ratio served as the based control. The other three super plasticized concretes tagged E1, E2 and E3 were of 0.3 water cementitious materials ratio (w/cm) with varied percentages of a super plasticizer. 60 concrete specimens were cast individually for beams, cubes and cylinders and de-moulded after 24 hours and moist cured till the day of their respective tests. At different days of curing of 7, 28, 56, 90 and 120 days as programmed, compressive, flexural and tensile splitting strength tests were carried out respectively and appropriately. The workability test results on fresh concretes showed that the values of both slumps and compaction factors were increasing progressively as the dosage of super plasticizer was increasing. Also, the flexural, compressive and tensile splitting tests results showed that hardened concrete strength increased similarly as workability of the fresh concrete correspondingly. Significantly, equally combined 12 mm and 19 mm nominal maximum size aggregates at 50% each was found well graded and fitted into an envelope than individual single aggregate gradation of 12 mm and that of 19 mm. The use of 19 mm aggregate gradation in the combined mix makes the concrete more economical for being cheaper than 12.5 mm nominal maximum aggregate.

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Diabetes is one of the emerging disease which leads to the other chronic diseases. As per the WHO we have 425 millions diabetes by 2025 it may increases to unimaginable number by 2030. Here we attempted to predict diabetes by using machine learning algorithms. Many works presented with SVM, ANN etc algorithms were not efficient. In this paper we used advanced and integrated machine learning algorithms with an effective data pre-processing techniques. We improve the results by using ensemble methods that perform bagging and tuning methods. We made an intensive literature survey and concluded that most of the existed works not used PCA for dimensionality reduction and solves multicollinearity problem for highly correlated attributes. They failed to explain about refinement of the proposed results due to limitations of domains. Due length of the datasets could not explain about more classification techniques and could not extended their works for other domains. Here we proposed a development of predictive model for medical chronic diseases (diabetes, liver, kidney etc) using machine learning algorithms.

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During modern years, the advancement in Delhi leads to increase in pollution. Air pollution is able to cause a drastic impact on human health and environment. So this paper explored the far-reaching outcome of ambient air smog in sensitive stations of Delhi and also detects the diseases caused by the air pollutions. Based on that, the data mining algorithm "Naive Bayesian" is used. The various air pollutants like Sulphur dioxide (SO2), Nitrogen dioxide (NO2), Respirable particulate matter (RSPM), Suspended Particulate Matter (SPM) [1] and weather conditions and seasons have been noticing in this paper. By using the above data mining algorithm, this paper proposes which are used to detect the various air pollution diseases and will afford the awareness about that syndrome to people.

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Abstract:

A high-precision control law of a second-order nonlinear object was synthesized based on the method of minimizing local functionals. It provides control under uncertainty conditions without using information about the derivatives of the controlled variable. Criteria for the selection of control law parameters are developed. The system of automatic control of the vertical movement of a remotely-operated underwater vehicle was synthesized. Computer simulation results showed high dynamic control accuracy.

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This investigation carried to analyze the possible structural solutions for the breakwaters of new Al-Faw port in Iraq. This investigation deals with the description of the general characteristics of the breakwaters and with the typical structural solution adopted, attributed to the environmental conditions at Al-Faw port, its location and description the structural design criteria to be adopted in the Al-Faw breakwaters at the eastern and western side of Al-Faw port.

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This article presents the concept of systems with distributed parameters and investigates the method of distributed controller synthesis and a homogeneous control object. This article analyzes main methods of transferring heat energy. On the basis of the heat-transfer equation, the function of initial heating has been obtained, and the process has been mathematically simulated, and the results obtained have been analyzed. The practical results of this research make it possible to draw a conclusion about the possibility of building a silicon-carbide heating element made in the shape of an isotropic rod.

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Information is a message in the form of a utterance or phrase that can consist of symbols, or meanings that can be interpreted from a message or a collection of messages. Steganography is a technique that can be used to hide information on a media. In the digital era, the media used can be audio, image, or video. In its use, the concealment of messages is done by making small changes to a digital medium so as not to attract the attention of other people or attackers. In general, the concealment of a data or message on the image media is a technique that is often used in the implementation of steganography. In the use of image media, steganography can be implemented with existing methods; in this journal will be implemented Least Significant Bit (LSB) and Spread Spectrum method, which will further determine the analysis of image quality and comparison of both methods.

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In this paper the reconfigurable patch and ground plane used as a technique for enhancing band width of microstrip antenna, traditional rectangular patch microstrip antenna is used as a comparison for result with the proposed antenna design. The design is a periodic structure on patch with defected ground plane to allow the surface wave and multi modes are excited. The result is simulated using HFSS. The bandwidth of the traditional rectangular patch antenna is about 0.13 GHz, while the proposed antenna gives us about 0.92 GHz. The proposed antenna can be used in the C-band wireless communication.

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Constructions in the urban environment have a strong impact on microclimate parameters at local scale by modifying the distribution of wind flow between surfaces. This distribution directly impacts comfort or thermal discomfort in outdoor public spaces. This work aims to evaluate, through modeling and numerical simulation, an aerodynamic model for predicting aerodynamic atmospheres at the urban scale. To characterize the urban flow, we chose a semi-empirical one-dimensional model for the determination of urban wind speed profiles Nicholson (1975) coupled with the AROME model. The simulation results were compared with the measurement data obtained during an experimental campaign conducted in Morocco by Erik Johansson (2006), in order to validate the relevance and robustness of the numerical model under Moroccan urban climate.

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Shield was used as protection from danger centuries ago. Until this moment, there was still no shield available for firefighting purpose in safe and rescue operation. This factor has put a limit to firefighters, causing death to many victims who were in critical and dangerous situation. In this project, conceptual design will be proposed aimed to protect firefighters against fire and heat. The project was based on the existing design of Federal Reserve Unit (FRU) shield and innovated by adding the application of resisting fire. The methodology used are customer survey to fire fighters, house of quality in defining customers’ needs, morphological chart in defining concepts, Rula-analysis in measuring ergonomic score and Pugh method for selection of best design. Carbon fibre was selected as the main material for the shield because it has a very low material density of approximately 1.75 g/cm3 and very high melting point of approximately 3500 °C. In Rula-Analysis, the ergonomics final score was 3. Results show that carbon fibre is appropriate for lightweight and fire-resistant shield. Ergonomics score of 3 for standing and kneeing position while holding shield is acceptable and further investigation can be recommended.

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Neuromorphic computing is an emerging architecture to address the issues of parallel computing like energy efficiency, size and speed. In standard neural network the basic computation is matrix multiplication between inputs to the neurons and their weights. This type of heavy computation can be handled conventionally with high end Graphics Processing Units (GPUs) effectively. The current technologies like Parallel CPUs and GPUs can provide parallel computation, but by incurring heavy computation and power consumption overheads. This has motivated research in hardware implementation of spiking neural networks with silicon technologies. The hardware implementation of event driven networks can drastically reduce the computational load and hence the power consumption. This survey paper discusses the various hardware implementations of spike neural networks (SNNs) and how they address different issues related to parallel computation of neural network functions.

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The face load factor KH, which in rating equations represents the load distribution over the face width in meshing gears is one of the most important items for a gear strength calculation. In this study, by implementing various profile and lead modification, the load distribution factor will be calculated to select the optimal profile and lead modification values through KissSoft machine design software for the same input parameter. Based on the KissSoft results the optimal profile and lead modification values are taken to avoid gear tooth damage by reducing the load distribution factor. The effects of the profile and lead modifications (Tip and root relief, Helix angle modification, End relief and longitudinal crowning) and corresponding load distribution factors and gear strengths are illustrated with and without profile and lead modification with the same input parameters. By providing optimum lead modifications, kHb value reduced from 1.80 to 1.1. i.e. 39% load carrying capacity increased and Hertzian stress value reduced from 1860 N/mm² to 1275 N/mm² i.e. 31% stress reduction.

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