Abstract: A novel method for connecting multiple existing columns which are retrofitted into vapor-liquid contacting devices with trays or packings suitable for the operation of a three-phase (vapor-liquid-liquid) extractive distillation column for aromatics recovery. The retrofitted columns are connected by a vapor transfer line to transfer the vapor phase from the top of the lower column to the bottom of the upper column, and by a liquid transfer line to transfer the liquid phase from the bottom of the upper column to the top of the lower column of the three-phase extractive distillation column.

Abstract: A multilevel LINC transmitter. The multilevel LINC transmitter comprises a multilevel signal component separator, a phase modulator block, and an RF block. The multilevel signal component separator comprises a multilevel scaler and converts a base band signal to constant envelope signals. The phase modulator block is coupled to the multilevel signal component separator. The RF block comprises a plurality of power amplifiers coupled to the phase modulator block and the multilevel scaler and a power combiner coupled to the power amplifiers.

Abstract: A multilevel LINC transmitter. The multilevel LINC transmitter comprises a multilevel signal component separator, a phase modulator block, a mixer block, an up-converter block, a predistorter and an RF block. The multilevel signal component separator comprises a multilevel scaler and converts an input signal to phase signals. The phase modulator block and the predistorter are coupled to the multilevel signal component separator. The mixer block is coupled to the phase modulator block and the predistorter. The up-converter block is coupled to the mixer block. The RF block comprises a plurality of power amplifiers coupled to the up-converter block and a power combiner coupled to the power amplifiers.

Abstract: A predicted parallel branch slicer for use in an adaptive decision feedback equalizer includes Mk adders commonly receiving a signal to be processed and respectively receiving Mk preset values, and performing respective addition operations to generate Mk output signals; Mk slicers in communication with the Mk adders, receiving and processing the Mk output signals to obtain Mk signals of Mk levels, respectively; a multiplexer in communication with the Mk slicers, receiving the signals of the Mk levels; and k delay units interconnected with one another in series and being in communication with the multiplexer, and generating k selection signals of different delay time in response to an output of the multiplexer, the selection signals being provided for the multiplexer to select one of the signals of the Mk levels to be outputted.

Abstract: An integrated, continuous process for transforming feedstock, e.g., reformate, which contains high levels of benzene into a low-benzene content feedstock that is suitable for gasoline blending initially removes benzene from the reformate by extractive distillation, then partially hydrogenating the high purity benzene into cyclohexane under mild conditions in a one-stage hydrogenation reactor, and thereafter recovering a cyclohexane product with high purity from the hydrogenation reactor effluent in a back-end purification step using extractive distillation. The initial or front-end separation step yields a low-benzene content reformate.

Abstract: A discrete multi-tone (DMT) communication system is provided herein, replacing the conventional inversed discrete Fourier transform (IDFT) and DFT with IDHT (together with the complex-to-real transformation) and a DHT alone respectively at the transmitting end and the receiving end. A DHT-based frequency-domain equalizer (FEQ) at the receiving end equalizes each of the 0-th to (N?1)-th DHT subchannels, where N is the number of point of the DHT. Finally, each of the 0-th to (N/2?1)-th subchannels of the DMT system is obtained by combining the k-th and (N-k)-th subchannels of the DHT-based FEQ for k=0, 1, . . . , (N/2?1).

Abstract: A gas-liquid contactor baffle includes a body having a first portion, a second portion and a middle portion, the middle portion being positioned between the first portion and the second portion. The middle portion is a corrugated sheet having a first face and a second face. The corrugated sheet has alternating ridges and open ended channels extending across each of the first face and the second face between the first portion and the second portion. The first portion has a first collection channel adapted to collect liquids from the open ended channels of the middle portion when flow is along the first face in a first direction. The second portion having a second collection channel adapted to collect liquids from the open ended channels of the middle portion when flow is along second face in a second direction.

Abstract: An efficient method for calculating the step-sizes for a frequency-domain equalizer of a discrete-multitone communications system using signal power estimation and tone grouping (SPE-TG) while on-line. The SPE-TG method is used to calculate a plurality of subchannel step-sizes which are then stored in a lookup table. When on-line, the method uses signal power estimation to select step sizes for each tone, and uses these step sizes for frequency domain equalization. The SPE-TG method simplifies the calculations necessary for frequency domain equalization, thereby saving significant hardware and/or processing resources. The SPE-TG method is reliable and robust, and does not depend upon assumptions about the line, location, or channel.

Abstract: The invention disclosed relates to catalytic distillation column internals providing improved liquid and catalyst contacting for simultaneous catalytic reaction and separation of the reaction mixture. The invention provides an improved catalytic distillation system providing optimum balance of catalytic reaction and mass transfer steps, wherein distribution, mixing and application of liquid to the reaction zone and separation zones is better controlled and more uniformly applied. At least one catalyst bed is situated in at least one receiving pan of a distillation tray so that said tray performs the functions of both of the reaction section and the separation section of the catalytic distillation column simultaneously within a stage.

Abstract: Providing multi-path echo cancellation comprises providing a main echo signal corresponding to a main echo section of an echo response and providing a plurality of tail echo signals, each of the plurality of tail echo signals corresponding to respective tail echo sections of the echo response. Next, providing a multi-path echo canceller comprises summing the main echo signal and the plurality of tail echo signals to provide a synthesized echo.

Abstract: Disclosed is a distillation system and method for recovering acetic acid from a feed stream containing acetic acid and water stream generated during terephthalic acid production. The invention includes a liquid-liquid extraction column and a dehydration distillation column utilizing azeotropic distillation or conventional to recover the acetic acid. The liquid-liquid extraction column is installed upstream from the dehydration distillation column. The liquid-liquid extraction column produces an extract of an extraction solvent and acetic acid which is sent to the dehydration distillation column to separate the extraction solvent and acetic acid. The dehydration distillation column may be used with or without a condenser system to recover the energy. The condenser system is a steam generator that condenses the vapor into a concentrated acetic acid stream while generating a low pressure steam. Any remaining acetic acid in water is sent to a waste water recycling facility.

Abstract: A highly effective liquid-liquid extraction process to remove nitrogen compounds and especially basic nitrogen compounds from aromatic light petroleum oils with excellent recovery employs de-ionized water, which can be acidified, as the extractive solvent. The product is an aromatic hydrocarbon with ultra-low amounts of nitrogen poisons that can deactivate acidic catalysts. The extracted oils are suitable feedstock for the subsequent catalytic processes that are promoted with the high performance solid catalysts, which are extremely sensitive to nitrogen poison.

Abstract: The present invention provides a soft-threshold-based multi-layer decision feedback equalizer, including a feed forward filter for receiving a transmitted data, a feed backward filter, an adder and a soft-threshold-based multi-layer decision engine (STM engine). The adder is coupled to an output end of the feed forward filter and an output end of the feed backward filter, and generating an output of the equalizer. The STM engine includes a threshold detector, a data detector and a state machine. The STM engine detects whether or not the output of the equalizer is in a defined threshold value so as to determine the STM works as a slicer or delay decision.

Abstract: The contact between, for example, ascending liquid droplets of lighter liquid, as the dispersed phase, and heavier liquid, as the continuous phase, flowing across perforated trays in a flooded liquid/liquid contacting column, is enhanced by providing upstanding baffles on lower trays, interspersed with depending baffles from the trays above. The baffles cause the heavy liquid to flow along an undulating path. Flow distributing partitions extend along the undulating flow path, between the baffles, to distribute liquid flow across the trays. The roles of the lighter liquid and the heavier liquid may be reversed as phases.

Abstract: A method for implementing a multiplier-less FIR filter is disclosed, in which the FIR filter performs the convolution of H ? ( z ) = ? k = 0 N - 1 ? ? h k ? z - k , where hk is the k-th coefficient of the FIR filter. The dynamic range of the filter coefficients is compressed by a transformation: H ? ? ( z ) = H ? ( z ) ? ? i = 1 m - 1 ? ? ( 1 + ? i ? z - ? ) m ? i = 1 m - 1 ? ? ( 1 + ? i ? z - ? ) m , where parameters ? and ? are chosen depending on filter type, ?1??i?1, and m denotes iteration numbers of coefficient operation of transformation, so as to avoid the serious quantization error caused by the phenomenon of SPT distribution. Then, the compressed coefficients are quantized into SPT numbers, and the coefficients are optimized by removing redundant STP numbers.

Abstract: A CORDIC method and a CORDIC architecture applied in vector rotation are disclosed. An elementary angles set is extended by representing the elementary angles as the arctangent of the sum of two single signed-power-of-two terms to an extended elementary angles set. A combination of elementary angles is found from the extended elementary angles set such that the residue angle error can be minimized. A quantized scaling factor is used to scale the combination of elementary angles after being micro-rotated.

Abstract: The present invention may significantly reduce the number of iteration of the time recursive IFFT structure. First, the real and imaginary part of the input signal are modified based on the symmetric and anti-symmetric. Then, they are mixed together by an adder and fed into the lattice module. Next, an IFFT is performed on the modified input data sequence to generate a transformed sequence. Through the symmetric and anti-symmetric properties, the redundant terms may be eliminated.

Abstract: A method of mixed-scaling-rotation CORDIC (MSR-CORDIC) with scaling-free rotational operations is disclosed. An elementary angles set is extended by representing the elementary angles as the arctangent of the division of two single signed-power-of-two terms to an enhanced extended elementary angles set. A combination of elementary angles is found from the enhanced extended elementary angles set such that the residue angle error can be minimized. A MSR-CORDIC operation is used to perform the rotating and scaling transformation simultaneously.

Abstract: A predicted parallel branch slicer for use in an adaptive decision feedback equalizer includes Mk adders commonly receiving a signal to be processed and respectively receiving Mk preset values, and performing respective addition operations to generate Mk output signals; Mk slicers in communication with the Mk adders, receiving and processing the Mk output signals to obtain Mk signals of Mk levels, respectively; a multiplexer in communication with the Mk slicers, receiving the signals of the Mk levels; and k delay units interconnected with one another in series and being in communication with the multiplexer, and generating k selection signals of different delay time in response to an output of the multiplexer, the selection signals being provided for the multiplexer to select one of the signals of the Mk levels to be outputted.

Abstract: A fast convergent pipeline adaptive decision feedback equalizer using a post-cursor processing filter is disclosed, which includes a feed-forward equalizer, a post-cursor processing filter, an adder, a slicer, a register, a pipelined feedback equalizer, a subtractor and a updating device. The pipelined feedback equalizer has a delay device coupled to the register for delaying its output signal, and a feedback equalizer coupled to the delay device for eliminating the post-cursor of the output signal. By using the post-cursor processing filter (PCF), it increases the operating clock rate with arbitrary speedup factor, and improves the convergence rate of the overall system.