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In order to determine if the CFB panel is superior to the CHB, this study, "Comparative Study of the Mechanical Properties of Coconut Fiber Cement Board and Concrete Hollow Blocks," compared the two products' prices, dead loads, and compressive strengths. Three samples of each of the two products were used in the experiment, which the researchers conducted. The tensile strength test, parametric test, and Universal Testing Machine (UTM) were used to gather the data for this study. The compressive strength test was performed at the TERMS Concrete and Materials Testing Laboratories Inc. in Tayuman, Manila. The study assumed that: CFBs are less expensive than CHBs; carry less weight than CHBs; and have greater structural strength. Results show that CFB has an average compressive strength of 1,004.167 PSI. In comparison to a CHB, the CFB has more compressive strength. The researchers also concluded that a CFB would carry less weight than a CHB at 5.4721 lb. In both panels' cost analyses, the price of CFB is deemed to be higher than the price of CHB. Fiber Cement Board (CFB) offers a substantially more cost-effective alternative. By enhancing the walling system for residential establishment, this study will benefit the Philippine construction industry. [ABSTRACT FROM AUTHOR]

In order to determine if the CFB panel is superior to the CHB, this study, "Comparative Study of the Mechanical Properties of Coconut Fiber Cement Board and Concrete Hollow Blocks," compared the two products' prices, dead loads, and compressive strengths. Three samples of each of the two products were used in the experiment, which the researchers conducted. The tensile strength test, parametric test, and Universal Testing Machine (UTM) were used to gather the data for this study. The compressive strength test was performed at the TERMS Concrete and Materials Testing Laboratories Inc. in Tayuman, Manila. The study assumed that: CFBs are less expensive than CHBs; carry less weight than CHBs; and have greater structural strength. Results show that CFB has an average compressive strength of 1,004.167 PSI. In comparison to a CHB, the CFB has more compressive strength. The researchers also concluded that a CFB would carry less weight than a CHB at 5.4721 lb. In both panels' cost analyses, the price of CFB is deemed to be higher than the price of CHB. Fiber Cement Board (CFB) offers a substantially more cost-effective alternative. By enhancing the walling system for residential establishment, this study will benefit the Philippine construction industry. [ABSTRACT FROM AUTHOR]

Since commissioning, 100 MW Coal fired Tarahan Power Plant which uses Circulating Fluidized Bed (CFB) Boiler suffered many problems, especially on water wall tubes abrasion. This condition is merely due to higher wearing rate of bed particles to the wall tubes than that of expecting design. In order to reduce wall tube wearing rate, seven layers anti abrasion refractory beam will be installed at the elevation of 16 up to 40 m around the wall tubes. Before implementation computational fluid dynamics (CFD) modeling was conducted to show the flow of the bed materials through the water wall tubes and the influence of refractory beam on heat transfer reduction was also studied. The results show that the flow of the bed material changes and tends to reduce their friction on the wall tubes without reduces heat transfer rate significantly. Since more than six months of the anti abrasion beam implementation, boiler shutdown due to wall tube abrasion was not observed yet. It means that abrasion beam installation could at least reduce significantly wearing rate. [ABSTRACT FROM AUTHOR]

Energy consumption in wireless sensor networks (WSN) was always a basic constraint to respect. But, with the appearance of Wireless Multimedia Sensor Networks (WMSN), another basic constraint comes from added, which is the traffic performance in terms of delay, throughput, and Packet Delivery Rate (PDR). The choice of channel access method can help us to better respond the two constraints in WMSN. The Distributed Coordination Function (DCF) access method has been frequently used by WSN with different modifications to reduce energy consumption. But in the WMSN, we must take into consideration as well the traffic performance. Hence the idea to study the feasibility of using an access method of the IEEE 802.11e in WMSN. In this paper we will analyze energy consumption and evaluate the performance of the 802.11e Enhanced Distributed Channel Access (EDCA) with and without the mechanism Contention Free Burst (CFB), compared with IEEE 802.11 DCF. The results show that the use of EDCA CFB gives better performance, and offers a very good relationship between energy consumption and traffic performance, which is recommended in WMSN. [ABSTRACT FROM PUBLISHER]

Processing of large amount of data is an important aspect of Speech Recognition (SR). However, to formulate speech recognition system in small devices is not simple. This paper suggests Digital Signal Processor (DSP) based speech recognition system with improved performance in terms of recognition accuracies and computational cost. The comprehensive survey of various approaches of feature extraction, like Mel Filter Banks with Mel Frequency Cepstrum Coefficients (MFCC) and Cochlear Filter Banks (CFB) with Zero-crossings is given. Amongst various feature classification techniques, the suitability of the Support Vector Machine (SVM) classifier for the proposed system is significant. [ABSTRACT FROM PUBLISHER]

Wireless Local Area Network (WLAN) based on IEEE 802.11e provides Quality of Service (QoS) support at the Medium Access Control (MAC) sublayer. IEEE 802.11e MAC sublayer uses a function called Hybrid Coordination Function (HCF) with Enhanced Distributed Channel Access (EDCA). EDCA is a QoS mechanism that provides a priority scheme by differentiating interframe space and contention window size, it also uses Contention Free Bursting (CFB) scheme that can improve the efficiency of the system. In this study we analyzed performance of wireless network based on IEEE 802.11e in supporting QoS for multimedia transmission. We use three different types of traffic, those are voice, video, and data to analyze the performance of the network in supporting multimedia transmission. [ABSTRACT FROM PUBLISHER]

Two circular electrical capacitance tomography (ECT) sensors have been designed and used to monitor the solids flow in a cold circulating fluidised bed (CFB) with an external heat exchanger (EHE). The ECT sensors have eight electrodes and were mounted in the side tube and return tube above the EHE via pneumatically controlled loop seal respectively. Dynamics test with different process conditions are given. Image reconstruction results in the cross-sectional of the two tubes are compared and averaged measured signals are given. The results indicate that the solid flow can be controlled in the EHE based on ECT measurement. [ABSTRACT FROM PUBLISHER]

The emission of sulfur dioxide (SO2) produced by the sinter machine takes up more than 50% of the total SO2 emission of the iron and steel industry in China. So it is necessary to take effective measures to strengthen the control of sintering gas desulphurization. A novel sintering gas desulphurization technology, the inner and outer circulating fluidized bed (IOCFB) which is suitable for retrofitting the existing metallurgical industry plants in China will be introduced in this paper. The novel composite internals which can improve the removal efficiency of SO2 is also described. Current research and development needs for IOCFB are to further increase desulphurization efficiency and improve the reliability of plant components. To solve these problems, a pilot plant emulating IOCFB desulfurization processes had been built. [ABSTRACT FROM AUTHOR]

recent year, the Circulating Fluidized Bed (CFB) Boilers have adopted to build a fossil power plant in Taiwan. Most of the fire petroleum utilizes coke as fuel, which produces more than 1 million tons of fly ashes, and disposed into landfill. The property and behavior of CFB fly ash is different with C type and F type in ASTM C 618. According to CFB fly ashes, it have high content of CaO, which has an own self-cementing property. This research focuses on utilization of CFB fly ash on heavy-load pavement's base layer in industrial park road and state route. The CFB fly ashes were replaced of 30% and 15% grade in various sessions for road test. From the result of Laboratory test, short term pavement performances and underground water qualities are evaluated at the same time. By comparing with the original grade in the lab, the California Bearing Ratio (CBR) Value of grade with 30% and 15% were significantly improved. The mass metal content of CFB fly ash was also below the limit of Environment Protection Agency in Taiwan. [ABSTRACT FROM AUTHOR]

This work aims to present a pure 3-D CFD model, accurate and efficient, for the simulation of a pilot scale CFB hydrodynamics. The accuracy of the model was investigated as a function of the numerical parameters, in order to derive an optimum model setup with respect to computational cost. The necessity of the in depth examination of hydrodynamics emerges by the trend to scale up CFBCs. This scale up brings forward numerous design problems and uncertainties, which can be successfully elucidated by CFD techniques. Deriving guidelines for setting a computational efficient model is important as the scale of the CFBs grows fast, while computational power is limited. However, the optimum efficiency matter has not been investigated thoroughly in the literature as authors were more concerned for their models accuracy and validity. The objective of this work is to investigate the parameters that influence the efficiency and accuracy of CFB computational fluid dynamics models, find the optimum set of these parameters and thus establish this technique as a competitive method for the simulation and design of industrial, large scale beds, where the computational cost is otherwise prohibitive. During the tests that were performed in this work, the influence of turbulence modeling approach, time and space density and discretization schemes were investigated on a 1.2 MWth CFB test rig. Using Fourier analysis dominant frequencies were extracted in order to estimate the adequate time period for the averaging of all instantaneous values. The compliance with the experimental measurements was very good. The basic differences between the predictions that arose from the various model setups were pointed out and analyzed. The results showed that a model with high order space discretization schemes when applied on a coarse grid and averaging of the instantaneous scalar values for a 20 sec period, adequately described the transient hydrodynamic behaviour of a pilot CFB while the computational cost was kept low. Flow patterns inside the bed such as the core-annulus flow and the transportation of clusters were at least qualitatively captured. [ABSTRACT FROM AUTHOR]

The flow structure in the CFB (circulating fluidized bed) riser has been investigated. Experimental studies were performed in a cold square section unit with 270 mm×270 mm×10 m. Since the drag force model based on homogeneous two-phase flow such as the Gidaspow drag model could not depict the heterogeneous structures of the gas-solid flow, the structure-dependent energy-minimization multi-scale (EMMS) model based on the heterogenerity was applied in the paper and a revised drag force model based on the EMMS model was proposed. A 2D two-fluid model was used to simulate a bench-scale square cross-section riser of a cold CFB. The typical core-annulus structure and the back-mixing near the wall of the riser were observed and the assembly and fragmentation processes of clusters were captured. By comparing with the Gidaspow drag model, the results obtained by the revised drag model based on EMMS shows better consistency with the experimental data. The model can also depict the difference from the two exit configurations. This study once again proves the key role of drag force in CFD (Computational Fluid Dynamics) simulation and also shows the availability of the revised drag model to describe the gas-solid flow in CFB risers. [ABSTRACT FROM AUTHOR]