Abstract: A preparative method for carboxylic acids is disclosed in the present invention. The method is characterized in that: compounds (II) are reacted in the presence of hydrogen peroxide and base to produce target products (I), as represented by the following reaction scheme: wherein R1 is aryl, pyridyl, pyrimidyl, pyridazinyl, pyrazinyl, benzothienyl, benzofuranyl, quinolinyl, isoquinolinyl, thiadiazolyl, C1-6 alkyl, C3-6 cycloalkyl, C2-6 alkenyl, C2-6 alkynyl and hydrogen; R2 is alkoxycarbonyl, alkylaminocarbonyl, aminocarbonyl, alkylthiolcarbonyl, cyano, sulfonyl, sulfinyl, carbonyl, aldehyde, carboxyl, nitro, alkyl and hydrogen; R3 is alkoxycarbonyl, alkyl amido carbonyl, aminocarbonyl, cyano, sulfonyl, sulfinyl, carbonyl, carboxyl and nitro. The present invention has the following main benefits: cheap and readily available starting materials, safe processes, high yield, good quality, which facilitates industrial production.

Abstract: A computing system includes a processor that estimates a pattern of a flow of a mixture of particles and a fluid in a tubular structure as a stationary bed flow, a dispersed flow, or a transitional flow that is relative to the stationary bed and dispersed flows. The processor estimates a plurality of parameters based on the estimated pattern. The processor determines a plurality of dimensionless parameters, based on the estimated parameters. The dimensionless parameters include a first dimensionless parameter corresponding to an effect of turbulence on the flow and a second dimensionless parameter corresponding to an effect of gravity on the flow. The processor characterizes the pattern of the flow as the stationary bed flow, the dispersed flow, or the transitional flow, based on the dimensionless parameters. The processor models the flow based on the estimated pattern if it is determined that the characterized pattern matches the estimated pattern.

Abstract: Methods and systems are presented in this disclosure for accurate modeling of near-field formation in wellbore simulations. The approach presented herein is based on splitting a transient three-dimensional solution of finding heat and mass transfer parameters in a wellbore and a near-wellbore region into coupling modeling of a flow inside the wellbore with several transient two-dimensional solutions in the vicinity to the wellbore.

Abstract: A preparative method for carboxylic acids is disclosed in the present invention. The method is characterized in that: compounds (II) are reacted in the presence of hydrogen peroxide and base to produce target products (I), as represented by the following reaction scheme: wherein R1 is aryl, pyridyl, pyrimidyl, pyridazinyl, pyrazinyl, benzothienyl, benzofuranyl, quinolinyl, isoquinolinyl, thiadiazolyl, C1-6 alkyl, C3-6 cycloalkyl, C2-6 alkenyl, C2-6 alkynyl and hydrogen; R2 is alkoxycarbonyl, alkylaminocarbonyl, aminocarbonyl, alkylthiolcarbonyl, cyano, sulfonyl, sulfinyl, carbonyl, aldehyde, carboxyl, nitro, alkyl and hydrogen; R3 is alkoxycarbonyl, alkyl amido carbonyl, aminocarbonyl, cyano, sulfonyl, sulfinyl, carbonyl, carboxyl and nitro. The present invention has the following main benefits: cheap and readily available starting materials, safe processes, high yield, good quality, which facilitates industrial production.

Abstract: A zeroing method and zeroing device for an optical time-domain reflectometer (OTDR) are disclosed. The zeroing method includes: before starting the optical time-domain reflectometer, when a laser device is in an off state, sending a zeroing signal; and performing zeroing processing according to the zeroing signal. In the embodiments of the present invention, the feedback zeroing can be performed on a receiving circuit by utilizing the idle time prior to a test or during the test, thus the influence of an offset voltage is reduced, and a problem of operational-amplifier zero drift also can be solved in the meantime, which improves a detectability of the OTDR, and overcomes a disadvantage that a manual zeroing method is not intelligent and a measured waveform introduced in an automatic zeroing method is bad.

Abstract: Disclosed are a passive optical tag, an optical read/write device and an intelligent optical distribution network. The passive optical tag includes: an optical receiver, an optical transmitter, a chip and a photocell, where the optical receiver is connected with the chip and is configured to receive an optical signal, convert the optical signal into an electrical signal and send the electrical signal to the chip; the chip is configured to process the electrical signal and store tag information; the optical transmitter is connected with the chip and is configured to modulate the electrical signal sent by the chip into an optical signal and transmit the optical signal obtained by modulation; and the photocell is configured to convert optical energy into electrical energy and store the electrical energy, and provide electrical energy to the optical receiver, the optical transmitter and the chip.

Abstract: A computer implemented method, system, and computer program product are provided for determining flow control device (FCD) properties for a gas injection well that would yield a prescribed shape of a gas injection front according to a target gas injection profile. An FCD distribution function is adjusted based on the results of a simulation of injected gas flow distribution in the gas injection well over a period of time. The simulation and resulting adjustment of the FCD distribution function is repeated until a convergence between a shape of a displaced oil volume front obtained using the adjusted flow control device distribution function and a target gas injection profile is reached within a predetermined convergence range. The FCD properties are then determined based on the adjusted FCD distribution function.

Abstract: The disclosed embodiments include a method, apparatus, and computer program product for determining optimal flow control device (FCD) properties that would yield to a prescribed shape of the injection flow rate profile. For example, in one embodiment, a computer implemented method is configured to perform the steps of: determining a reference location along a production length of the injection well; determining a reference value equal to the injection flow rate profile at the reference location along the production length of the injection well; defining a target injection profile using the reference value; determining a pressure distribution along the production length of the injection well based on the target injection profile; determining a FCD distribution profile using the target injection profile and the pressure distribution; and determining FCD properties that yields the target injection profile based on the FCD distribution profile.

Abstract: The disclosed embodiments include a computer implemented method, apparatus, and computer program product that includes executable instructions that when executed performs operations for determining flow control device properties for an injection well that would yield to a prescribed uniform or non-uniform accumulated injection profile along a production well.

Abstract: A zeroing method and zeroing device for an optical time-domain reflectometer (OTDR) are disclosed. The zeroing method includes: before starting the optical time-domain reflectometer, when a laser device is in an off state, sending a zeroing signal; and performing zeroing processing according to the zeroing signal. In the embodiments of the present invention, the feedback zeroing can be performed on a receiving circuit by utilizing the idle time prior to a test or during the test, thus the influence of an offset voltage is reduced, and a problem of operational-amplifier zero drift also can be solved in the meantime, which improves a detectability of the OTDR, and overcomes a disadvantage that a manual zeroing method is not intelligent and a measured waveform introduced in an automatic zeroing method is bad.

Abstract: The disclosure provides a method and a system for detecting a fiber fault in a Passive Optical Network (PON). The system comprises an optical path detection device, a Wavelength Division Multiplexing (WDM) coupler, a wavelength selection coupler, a branch fiber selector and a wavelength selection router. The detection system is attached to an original PON system, without influencing the operation of the original system while performing the detection. With the disclosure, the problem of being unable to determine whether there is a fault in a branch fiber due to the loss of an optical path detection reflection signal is solved, the branch fiber with a fault can be quickly located and fixed, thus the operational and maintenance costs of an operator are reduced.

Abstract: The present invention provides a method and apparatus for implementing trunk optical fiber protection in EPON. According to the technical scheme of the present invention, activating an optical module at a master PON port, deactivating an optical module at a standby PON port, configuring a service for the master PON port, and synchronizing static data and dynamic data to the standby PON port; synchronizing and adjusting a value of an MPCP counter at the standby PON port according to a value of an MPCP counter at the master PON port; and carrying out fault detection, transmitting an operating state to the standby PON port when the fault occurs, and performing a master-standby switch of the PON ports.

Abstract: The present invention discloses a method and system for accurate time transfer in PON. An Optical Line Terminal (OLT) ranges Optical Network Units (ONUs) and obtains ranging information, then, triggered by the periodic Pulse per n Second (PPnS), generates a PPnS timestamp based on the local reference counter and the Time of Day (TOD) above second; OLT transmits the ranging information, the periodic PPnS timestamp and TOD to ONUs; ONUs predicts the time of the next second according to said periodic PPnS timestamp, TOD and ranging information, and outputs the corresponding PPnS. The invention is characterized by the combination of the features of PON point to multi-point and PON ranging into its time transfer method, the high accuracy of time transfer, and the low hardware costs for OLT and ONU, as well as the extremely small bandwidth occupancy.

Abstract: The disclosure provides a method and a system for detecting a fiber fault in a Passive Optical Network (PON). The system comprises an optical path detection device, a Wavelength Division Multiplexing (WDM) coupler, a wavelength selection coupler, a branch fiber selector and a wavelength selection router. The detection system is attached to an original PON system, without influencing the operation of the original system while performing the detection. With the disclosure, the problem of being unable to determine whether there is a fault in a branch fiber due to the loss of an optical path detection reflection signal is solved, the branch fiber with a fault can be quickly located and fixed, thus the operational and maintenance costs of an operator are reduced.

Abstract: A method for performing optical fiber fault diagnosis in a passive optical network is disclosed in the present invention. The method includes: after receiving an optical fiber fault diagnosis message, a receiving module of an optical line terminal triggering a test module (S10); after triggered by the receiving module, the test module performing an optical time domain reflection test, and obtaining data information (S20) of the test; and a fault diagnosis module analyzing the data information, and performing optical fiber fault diagnosis (S30). An optical line terminal is also disclosed in the present invention, including a control module and an optical module, and the control module includes a receiving module and a fault diagnosis module, and the optical module includes a test module. In the present invention, the process of optical fiber fault diagnosis is performed in combination with PON network management system.

Abstract: The present invention provides a method and apparatus for implementing trunk optical fiber protection in EPON. According to the technical scheme of the present invention, activating an optical module at a master PON port, deactivating an optical module at a standby PON port, configuring a service for the master PON port, and synchronizing static data and dynamic data to the standby PON port; synchronizing and adjusting a value of an MPCP counter at the standby PON port according to a value of an MPCP counter at the master PON port; and carrying out fault detection, transmitting an operating state to the standby PON port when the fault occurs, and performing a master-standby switch of the PON ports.

Abstract: The present invention discloses a method and system for accurate time transfer in PON. An Optical Line Terminal (OLT) ranges Optical Network Units (ONUs) and obtains ranging information, then, triggered by the periodic Pulse per n Second (PPnS), generates a PPnS timestamp based on the local reference counter and the Time of Day (TOD) above second; OLT transmits the ranging information, the periodic PPnS timestamp and TOD to ONUs; ONUs predicts the time of the next second according to said periodic PPnS timestamp, TOD and ranging information, and outputs the corresponding PPnS. The invention is characterized by the combination of the features of PON point to multi-point and PON ranging into its time transfer method, the high accuracy of time transfer, and the low hardware costs for OLT and ONU, as well as the extremely small bandwidth occupancy.

Abstract: A paint pad with adjustable handle belong to painting tool field, includes a handle; a pad unite that includes a pad support body and a pad holder plate, the pad holder plate is connected to the bottom of the pad support body; wherein the pad support body has a handle groove on the top; a orientation part is under the groove, its up surface has a plurality of orientation teeth; the handle with plurality of adjusting teeth at the end of handle is located in the groove; a knob on the top of the pad support body can adjust the relationship between the orientation teeth and adjusting teeth. The conventional paint pad is fallible and instable for keeping stable angle between the handle and pad unite, it influences the painting route and uniformity, and reduces painting quality.

Abstract: A paint pad with adjustable handle belong to painting tool field, includes a handle; a pad unite that includes a pad support body and a pad holder plate, the pad holder plate is connected to the bottom of the pad support body; wherein the pad support body has a handle groove on the top; a orientation part is under the groove, its up surface has a plurality of orientation teeth; the handle with plurality of adjusting teeth at the end of handle is located in the groove; a knob on the top of the pad support body can adjust the relationship between the orientation teeth and adjusting teeth. The conventional paint pad is fallible and instable for keeping stable angle between the handle and pad unite, it influences the painting route and uniformity, and reduces painting quality.