48results about How to "Low test conditions" patented technology

The invention relates to a method for determining the rock conjugate damage strength through adopting supersonic waves. The method concretely comprises the following operations: 1, respectively arranging a pair of longitudinal wave probes on two ends of two mutually perpendicular diameters on a cross section in the middle of a rock sample, and respectively continuously testing rock sound wave speeds between the two mutually perpendicular diameters of the rock sample in a short time (such as 1-3s) interval in the rock sample loading process until the rock sample is destroyed; and 2, finishing the changing process of two mutually perpendicular radial sound wave longitudinal wave speeds with the axial stress of the rock sample after the test completion, and obtaining the rock conjugate damage strength which is the axial stress corresponding with the substantially reduced radial longitudinal wave speed. The rock sample longitudinal wave speed test of the two mutually perpendicular diameters is carried out to eliminate the error caused by axial crack orientation generated during the axial loading of the rock sample and improve the determination precision.

The invention provides a heat convection testing method and a system for a composite insulator including an artificial defect. The testing method comprises the steps of fixedly embedding a temperature measuring probe in the composite insulator and enabling the temperature measuring probe to be located on the junction face of a silicone rubber sheath and an epoxy resin core rod; adopting a direct current constant voltage source to perform power supply for the resistance defect of the composite insulator; utilizing the temperature measuring probe to perform real-time detection on the internal temperature of the composite insulator in the power supply process, recording the internal defect temperatures under different currents and using an infrared temperature measurement device to shoot and record the surface temperature distribution situation of the composite insulator; and performing compilation and analysis on recorded data to obtain the relation of the outer surface temperature rise and internal actual temperature rise of the composite insulator. The temperature measuring probe improvable in temperature and a special fixing method are adopted, reliable connecting strength, insulating strength and heating power can be achieved, and the measurement accuracy is finally ensured.

The invention discloses a method for testing initial position angle of a motor rotor and solves the technical problem that the prior art is high in requirements on initial position angle testing conditions of the motor rotor and difficult in actual operation. The method includes following steps: step 1, applying a current i on a to-be-tested motor to enable the same to run; step 2, after the motor runs, enabling the current i to be zero; step 3, measuring voltage ud and uq of a shaft d and a shaft q of a motor stator; step 4, calculating according to a triangular function relation between ud and uq to acquire initial position angle deviation theta err of the motor rotor. The initial position angle deviation of the motor rotor is calculated by directly using the voltage of the d shaft and the q shaft of the motor stator, and corresponding relation between voltage at the motor end in a motor controller and the initial rotor position angle is made clear; the method is simple and suitable for engineering site operation; online fault diagnosis and error correction control can be realized, and system function safety can be improved.

The invention discloses a function test method and a function test device of a DSP module in an FPGA chip, and belongs to the field of FPGA chip technology. The function test method includes the stepsof performing the same function configuration on each DSP module inside an FPGA chip, and reading an input excitation into each DSP module through an MEM module inside the FPGA chip; conducting an XOR comparison between an output result of each DSP module with an expected output result stored in the MEM module to obtain multiple sets of multi-bit XOR results of each DSP module; and performing feedback OR operation on the multiple sets of multi-bit XOR results of each DSP module in sequence to feed back a previous set of OR operation results back sequentially to undergo OR operation with the following set, so that the multiple sets of multi-bit XOR results are finally reduced to one bit output to obtain a test result of each DSP module. According to the invention, the requirement on test conditions can be minimized, and the function test on all the DSP modules in the FPGA chip can be completed simply by means of the MEM module in the FPGA chip.

The invention aims at providing a method for testing a size changing rate of a battery diaphragm, which can conveniently, quickly and accurately measure the size changing rate of the battery diaphragmand ensure the use safety of a lithium ion battery. The method comprises the following steps: A. intercepting a sample on a diaphragm material to be tested; B. cutting the sample according to a scheduled shape; C. testing the original size of the sample under the condition of the initial environment, and recording the original size; D. testing the scheduled time of the sample which is placed in atest environment; E. taking the sample out of the test environment, carrying out climate adaptation treatment, and measuring a final size; and F. calculating the size changing rate according to the original size and the final size of the tested sample. The method for testing the size changing rate of the battery diaphragm has simple steps and low test condition requirements, can conveniently andquickly test the size changing rate of the battery diaphragm by a comparison test of two environments; in addition, the method adopts a plurality of measures to reduce measuring errors and ensure theaccuracy of test data.

The invention, which belongs to the field of cable detection, relates to a shielding effectiveness measuring method of an electric vehicle high-voltage cable. The invention provides a method for measuring the shielding effectiveness of a high-voltage cable of an electric vehicle based on a network analyzer and a current probe, so that the length requirement on the measured shielding cable by the traditional long-line measurement method is eliminated. Furthermore, the invention provides a matching calculation formula of the shielding effectiveness of the shielding cable based on an actually measured scattering coefficient. Under the condition that impedance matching processing is not carried out on the measured cable and the terminating load, the shielding effectiveness of the cable is accurately measured, so that a problem that the impedance matching condition of shielding effectiveness measurement of the existing electric vehicle high-voltage shielding cable is difficult to meet is solved and the shielding effectiveness measurement difficulty of the shielding cable is reduced.

The invention discloses a method for identifying the resistance of tobacco to root rot caused by Fusarium tabacinum. The method comprises 1, culture of Fusarium tabacinum, 2, preparation of a Fusariumtabacinum liquid, 3, cultivation of tobacco seedlings, 4, pre-treatment on the tobacco seedlings, 5, inoculation with the Fusarium tabacinum, and 6, investigation to detect the resistance of the specie to the root rot caused by Fusarium tabacinum according to the disease conditions. The identification method can directly identify tobacco seedlings. Compared with the method for inoculation of a pot or a field with bacteria, the method is free of a complex process for pot culture after transplant, reduces work load, utilizes floating plate vaccination to inoculate with hundreds or thousands ofplants, enlarges the inoculation amount, greatly reduces identification time through direct inoculation in the seedling period, breaks the season limitation of the resistance of tobacco to root rot caused by Fusarium tabacinum and realizes identification in any seasons.

The invention discloses a testing device for near-field wave-absorbing material reflectivity. The device comprises a vector network analyzer which is connected with a coaxial flange clamp through a coaxial cable, the coaxial flange clamp is arranged on a support, a division board is arranged on the top of the coaxial flange clamp, and a sample placing part is arranged between the division board and the coaxial flange clamp. The invention further discloses a testing method of the testing device for the near-field wave-absorbing material reflectivity. The testing device for the near-field wave-absorbing material reflectivity has the advantages that the structure is simple, the manufacturing cost is low, low-frequency range (30 MHz-3 GHz) measurement can be achieved, operation is easy and convenient, the accuracy degree is high, and the repeatability is good.

The invention discloses a static loading device and method for an anti-slip test of an inclined supporting joint. A ground beam is horizontally and fixedly arranged on a test bed, counterforce beams are arranged on the upper part of the ground beam in parallel, and a first side column and a second side column are arranged between the counterforce beams and the ground beam in parallel; the upper end of the first side column is hinged to one end of the counterforce beams, the lower end of the second side column is fixedly connected with the other end of the ground beam, a pressure gauge is arranged between the second side column and a jack, and the upper end of the jack tightly abuts against the other end of the counterforce beams; the lower part of an inclined supporting joint test piece isconnected with the ground beam, and the upper part of the inclined supporting joint test piece is hinged to the counterforce beams; a hinged rotation center between the inclined supporting joint testpiece and the counterforce beams, a hinged rotation center between the first side column and the counterforce beams and the top surface position of the jack are arranged in line. The static loading device is low in manufacturing cost, high in reliability, simple to install, capable of achieving self-balance, simple in operation method in the static loading process, and low in test condition requirement.

The invention discloses a test device for friction resistance between a non-smooth surface and a solid wall surface, and relates to a resistance test device. The test device comprises a test base, a first test installation area and a second test installation area, wherein the first test installation area and the second test installation area are sequentially arranged on the test base; the first test installation area comprises a power transmission device; the power transmission device comprises a driving device and a torque measuring device; the driving device is in driving connection with thetorque measuring device; the second test installation area comprises a pressing device and a moving device; the power transmission device is coaxially connected to the pressing device; the pressing device is installed on the moving device; and the moving device is movably connected with the test base. The test device is multifunctional, small in occupied area, low in cost, convenient to operate and easy to disassemble.

The invention belongs to the technical field of geotechnical engineering tests, and discloses a portable restrictive double-sided shear strength test clamp and test method. The test clamp comprises aclamp body, a shear block, two hinge brackets and two side pressure plates; a shearing groove penetrating the upper surface and the lower surface is formed in the clamp body in the vertical direction,a test piece groove which horizontally extends towards the rear end face and does not penetrate through the clamp body is formed in the front end face, the two side pressure plates are symmetricallyarranged on the two sides of the test piece groove, universal heads are fixedly arranged in the outer sides of the side pressure plates respectively, spherical cavities are formed in the universal heads, and small steering balls capable of rotating along the inner walls of the spherical cavities are arranged in the spherical cavities; the two hinge brackets are symmetrically arranged in the two sides of the clamp body; and the shear block is arranged in the shearing groove. The test clamp is simple in structure, the variable can be controlled only by replacing a test piece and a weight in thetest process, the test process is effectively simplified, and the test cost is greatly reduced.

The invention discloses a canine distemper virus drying type real-time fluorescence PCR detection reagent, and belongs to the technical field of detection reagents. A method comprises the following steps: a, product specification and kit components; b, reagent preparation (carried out in a reagent preparation area); c, sample treatment and sample addition (carried out in a sample treatment area);d, PCR detection (carried out in a nucleic acid amplification region); and e, result analysis and determination. A sample is detected to be positive or negative by collecting fluorescence signals, theefficiency is high, operation is easy, the detection result needs to meet the necessary conditions, the characteristics of low cost, convenience, rapidness and low test condition requirement are achieved, the detection efficiency is improved, and the detection accuracy is also ensured.

The invention provides a method for determining ammonia nitrogen content in seawater by Nessler's reagent spectrophotometry. According to the method, the optimal addition amount of sodium potassium tartrate in a wide salinity range is found out by adjusting the concentration and volume of sodium potassium tartrate according to the salinity of a sample to be detected, that is, the interference of impurity ions such as Ca 2+, Mg 2+, Fe 2+ and Mn 2+ in the seawater sample can be eliminated only by using a sodium potassium tartrate solution as a masking agent, so that the Nessler reagent in the seawater is more stable in color development, and the method is wider in application range. According to the method, reagents such as sodium hydroxide are not needed as masking assistance, and the dosages of the potassium sodium tartrate and the Nessler reagent are less, so that the environmental pollution is reduced, and the cost is saved; besides, the method has the advantages of less interference, simplicity in operation, high speed, high recovery rate, good precision and the like.