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Data Reduction Strategies  Data reduction techniques can be applied 1o obtain a reduced representation of the data set that is much smaller in volume, yet. closely maintains the integrity of the original data, That is, míning on the reduced data set should be more efficient yet produce the same analytical results Data Cube Aggregation, where aggregation operations are applied to the data in the construction of a data cube. Attribute Subset Selection, where irrelevant, weakly relevant, or redundant attributes of dimensions may be detected and removed. Dimensionality Reduction, where the encoding mechanisms are used to reduce the data set size. Numerosity Reduction, where the data are replaced or estimated by alternative smaller data representations such as parametric models or no parametric methods such as clustering camping, and the use of histograms. Discretization and Concept Hierarchy Generation, where ranges or higher conceptual levels replace raw data values for attributes. Data d

Torque Converter The torque converter is a device used for the multiplication of torque. It consists of: (i) The impeller or the driving member, (ii) The turbine or driven member, (iii) The stator fixed to the frame through a freewheel. Torque Converter Diagram Torque Converter Operation Torque Converter Working  When the engine is started, the impeller starts rotating, the oil from the impeller is pushed into the turbine. The oil, having high kinetic energy from the engine through the impeller hits the outer edge of the turbine. This force will increase with the rise of engine speed. once it's nice enough the turbine starts rotating and therefore the vehicle moves. The fluid from the turbine is made to strike a stator, which changes it’s direction suitably so that the oil leaving g the stator strike the impel [er in a favorable direction i.e. in the same direction in which the impeller is turning. Thus repeated pushing of the turbine blades causes the torque on the turbine to incr

Difference Between Resistance and Impedance Impedance Impedance comprises of two things: reactance and resistance, making the resistance a subset of impedance. Impedance is a progressively broad term for resistance that additionally incorporates reactance. Impedance and reactance are both given in units of 'ohms' simply like resistance. Resistance Resistance is an idea utilized for DC (coordinate flows) while impedance is the AC (exchanging current) identical. Resistance is the restriction of an enduring electric flow. Unadulterated resistance does not change with recurrence, and normally the main time just resistance is considered is with DC (coordinate flow - not evolving) power. Resistance Vs Impedance Resistance is the restriction of the electrical flow stream. Resistance happens in AC and DC circuits. Notwithstanding Resistance, AC circuits additionally show Reactance. Reactance is likewise the restriction to the electrical flow stream. By its very nature,

Penetration Test  The penetration test a look at determines the hardness or softness of hydrocarbon by measuring the depth m tenths of an mm to that a regular loaded needle can penetrate vertically m 5 seconds. Sample eighteen maintained at a temperature of 25°C " The idea of a penetration take a look at is shown IN Fig one Indian normal institution has standardized the instrumentation and test procedure. Penetration Test Diagram Penetration Test Process The bitumen lS softened to a poor rm g consistency stirred thoroughly and poured into containers to a depth of at least 15 mm in excess of the expected penetration. The sample containers are then placed in a temperature-controlled water bath at a temperature of 25 degrees C for one hour. The sample with the container is taken out and the needle is arranged to make contact with the surface of the sample. The dial is set .to zero or the initial reading is taken and the needle is released for 5 seconds. The final reading is taken on

Terzaghi's Theory of One-Dimensional Consolidation The theory for the time rate of one-dimensional consolidation was initially planned by Terzaghi (1925). The underlying assumption in the derivation of the mathematical equations are as follows  The soil is homogeneous and isotropic.  The soil is fully saturated. The solid particles and water within the voids are incompressible. The consolidation happens because of the expulsion of water from the voids. The coefficient of permeability of the soil has the same value at all points and it remains constant during the entire period of consolidation. Darcy’s law is valid throughout the consolidation process. Soil is laterally confined, and the consolidation takes place only in the axial direction. Drainage of water also occurs only in the vertical direction. The interruption in consolidation is due entirely to the low permeability of the soil. There is unique. relationship between the void ratio and therefore th

Tertiary Winding Figure 1(a).shows the circuit diagram for the forward converter with tertiary winding added to the basic configuration. Such converters are used in computers, word processors, televisions, etc. Operation of Tertiary Winding When the transistor Q is turned on, due to the winding polarities, diode Dm is reverse-biased and does not conduct. However, when Q is turned off, Dm is forward-biased and the current flows through the tertiary winding as shown in Fig.1(b).  The residual energy in the transformer core is returned back to the dc source via diode Dm and the tertiary winding. This is how the tertiary winding helps to demagnetize the core and avoids the core saturation.  Due to the dot convention as shown in Fig. 1(a), the primary winding and tertiary winding will never carry current simultaneously. Associated waveforms are shown in Fig. 2. The dark areas on the waveforms of Fig.2 show the magnetizing-demagnetizing current, given as, Tertiary Winding Advantages (i) It n

Cycloconverters  A Cycloconverter is a device that converts ac power at one frequency into ac power at different frequencies without an intermediate dc link. A Cycloconverter is also called a cycle converter or frequency changer. In Cycloconverter, the output frequency and voltage can be changed independently and continuously with the help of control circuits. Principle of cycloconverter The principle of operation of a cycloconverter is based on the conversion of AC power from one voltage and frequency to another using a technique called frequency conversion. This is achieved by using a series of power electronic switchings devices such as thyristors or IGBTs. A cycloconverter is made up of two main sections: the input section and the output section. The input section is connected to the AC power source and the output section is connected to the load. The input section of a cycloconverter is made up of a series of thyristors or IGBTs that are connected in a bridge configuration. The th