摘要:
The present invention is related to synthesis of highly pure cationic surfactant products by eliminating or reducing impurities generation that has beset prior art. This is achieved through the N-acylation of ester of amino acid and its inorganic salts or its organic salts (e.g. amino acid or hydrochloride of amino acid or sulfate of amino acid or acetate of amino acid etc.) in non-hydrolytic or nearly non-hydrolytic reaction conditions involving mono or biphasic reaction system with fatty acid halide (C4 to C20), under moderate uniform basic condition yielding high purity N-acyl substituted amino acid ester, particularly ethyl lauroyl arginate. The present process achieves pH control through process strategy rather than the measurement and control steps. This ambient temperature process is stable through a range of temperature variation eliminating rigid low temperature control.
摘要:
The description provides processes for the regio and stereospecific synthesis of polyprenylatedquinone derivatives, such as Vitamin K1, K2 and Ubiquinone, exploiting dithioacetals, especially 1,3-dithiane, mediated Umpolung chemistry which works along a new concept “Inhibiting resonance delocalization (IRD)” to overcome isomerization generated due to delocalization of allyliccarbanion on the π-electron cloud of an allylic systems by the conventional synthesis.
摘要:
Various embodiments, including systems and methods, are described for providing digital coupons to third party network sites. In one representative embodiment, a computing device is provided, where a plurality of digital coupons are maintained in a memory associated with the computing device. Each digital coupon is directed to the purchase of at least one item through an electronic commerce system. A coupon service is implemented in the computing device that is configured to identify at least one of the digital coupons to present on a third party network site in response to a request for at least one of the digital coupons received from the third party network site based at least in part upon information contained in the request. The identified digital coupons are then sent to the third party network site.
摘要:
Various systems, methods, and other embodiments are described relating to the selection of digital coupons for display in network pages. In one embodiment, a plurality of coupon campaigns are maintained in a computing device for a plurality of entities in association with an operation of an electronic commerce system employed to sell a plurality of items over a network. Each of the coupon campaigns comprises at least one digital coupon to be applied to a purchase of at least one of the items. A network page is generated in the electronic commerce system to be rendered on a client. The network page is generated in association with the operation of the electronic commerce system. A subset of the digital coupons is determined to be included in the network page to present to a user.
摘要:
The present invention relates to circuits and methods for controlling one or more LED strings. The circuit comprises a programmable controller coupled to one or more detectors, wherein the one or more detectors are configured to detect one or more measurable parameters of one or more LEDs or LED drivers. The controller is configured to receive information from the one or more detectors related to the one or more measurable parameters and use that information to determine the desired drive voltage for the LED strings. The controller is associated with a power supply having power factor correction (PFC) capability. The controller provides the power supply with a control signal indicative of the desired drive voltage for one or more LED strings. The power supply also receives ac voltage and current waveforms as inputs and performs power factor correction and rectified waveforms related to the ac waveforms. The power supply generates the desired drive voltage based on the control signal.
摘要:
The present invention uses two transistors instead of a sensing resistor to provide a constant current source for a load such as an array of light emitting diodes (“LEDs”). In the present invention, a bias current is applied to a branch of the circuit. The drain-to-source voltages of two transistors are matched. The voltage at the gate of both transistors is controlled based on the bias current and the drain-to-source current of the first of the two transistors. The second of the two transistors is sized such that source current of the second transistor is a multiple of the source current of the first transistor for a given gate voltage. By the techniques of this invention, the load current in a circuit is efficiently kept constant at a multiple of the input bias current.
摘要:
In a multiple-user network communication system such as a satellite-based system, or in cable or wireless systems, the system resources, such as bandwidth, code allocation, and or slot timing, are allocated to users based in part on their class of service. The allocation provides for immediate allocation of the requested resources to a user having a verified high class of service so long as the resources are abatable or can be made available by tapping a resource reserve. If only a portion of the requested resources are available, they are made available immediately. From time to time, the resources available to at least one class of service are allocated among the users of that class of service, either equally, equally up to the requested resources, equitably, or in some systematic manner.
摘要:
In an asynchronous transfer mode (ATM) system, interleaved cells are formed at the transmit end by combining into each interleaved cell certain bits from each of plural different original ATM cells, the interleaved cells are transmitted over the communications link, and then deinterleaved at the receive end. Any bursty errors occurring on the communications link will, after deinterleaving, be spread out over multiple original ATM cells, maximizing the error correction for ATM cells and error detection for AAL capability and minimizing loss of data. The C1 byte in the Physical Layer Convergence Protocol (PLCP), which indicates the location of end of the PLCP frame, is protected against the burst errors by replication of C1 byte through inserting them in the growth bytes Z1 through Z4.
摘要:
A performance analysis system analyzes the performance of affiliate sites that provide links to specific items in an electronic catalog, and identifies catalog items that can be listed by such affiliate sites to improve performance. An association mining component analyzes transaction data attributable to specific categories of affiliate sites to identify items that are frequently purchased in combination by users of such sites. The detected item associations are used to evaluate, for a given affiliate site, whether significant disparities exist between the expected and actual sales quantities of specific items. The results of the analysis are incorporated into affiliate-specific performance reports, which may include specific recommendations for improving performance. The disclosed methods may also be used to analyze the performance of, and provide recommendations to, online sellers within a marketplace or auction system.
摘要:
Systems, circuits and methods for phase-shifting pulse width modulated signal generation are disclosed. In some embodiments, a phase-shifting pulse width modulation circuit is configured to output pulses based on an input pulse width modulated signal. The pulses are staggered relative to one another, and can be received by a light-emitting diode driver for driving a light-emitting diode string at one or more time periods. The phase-shifting pulse width modulation circuit can include a counter-based programmable delay subcircuit consisting of two counter-based programmable delay blocks.