Abstract: The present disclosure provides a control method for an AC-DC conversion circuit. The method includes: in an entire load range, acquiring circuit parameter information of the AC-DC conversion circuit; limiting an actual switching frequency or an actual switching period of the AC-DC conversion circuit within a preset working range according to the circuit parameter information. The AC-DC conversion circuit can meet requirements of Total Harmonic Distortion (THD), Power Factor (PF), efficiency and Electromagnetic Interference (EMI) and the like by adjusting the working information of the AC-DC conversion circuit through the preset working range.

Abstract: A method of fabricating an optical lens disclosed herein includes forming a layer of a flat lens structure on a front surface of a substrate, depositing a protective metal layer on the layer of the flat lens structure and on a back surface of the substrate, wherein the protective layer includes chromium, gold, titanium, or nickel, wherein the back surface is located opposite to and away from the front surface having the layer of the flat lens structure, irradiating the protective metal layer at the front surface with a laser to form a channel (i) through the protective metal layer, (ii) through the layer of the flat lens structure and (iii) in the substrate, removing the protective metal layer at the front surface and the back surface of the substrate, and separating the layer of the flat lens structure from the substrate to obtain the optical lens, wherein the channel has a depth defined by a thickness of the substrate remaining at the channel after irradiating the protective metal layer at the front surface

Abstract: Multilevel conversion circuit having a flying capacitor and method for precharging the same are provided. The multilevel conversion circuit includes: a first bridge arm including a plurality of switches connected in series; a second bridge arm including a plurality of switches connected in series and a flying capacitor group, midpoints of the two bridge arms connected to a power supply and an inductor to form a series branch; a DC bus capacitor to which the two bridge arms are connected in parallel; a first voltage clamping module connected between a first end of the flying capacitor group and a first end of the DC bus capacitor; and a second voltage clamping module connected between a second end of the flying capacitor group and a second end of the DC bus capacitor.

Abstract: A multilevel conversion circuit having a flying capacitor is provided, including: a first bridge arm; a second bridge arm including a flying capacitor, the midpoints of the second and first bridge arms connected to a series branch defined by a first current limiting circuit, a power supply and an inductor; a DC bus capacitor connected in parallel to the first and second bridge arms; a rectifier circuit having an input end coupled to the power supply and an output end connected to a first auxiliary power supply; and a controller coupled to the first auxiliary power supply and the plurality of switches of the second bridge arm to control corresponding switches of the second bridge arm, the power supply charges the flying capacitor through the corresponding switches of the first and second bridge arms and the first current limiting circuit.

Abstract: The present disclosure provides a power conversion device. The power conversion device includes the multi-level power factor correction circuit, the at least one output capacitor, the at least one input capacitor group, the first resonant conversion circuit and the second resonant conversion circuit. The at least one input capacitor group includes the first input capacitor and the second input capacitor. The at least one output capacitor is connected to an output part of the multi-level power factor correction circuit. The at least one input capacitor group is connected to the at least one output capacitor in parallel. The second input capacitor is connected to the first input capacitor in series. The input part of the first resonant conversion circuit is connected to first input capacitor in parallel. The input part of the second resonant conversion circuit is connected to the second input capacitor in parallel.

Abstract: The disclosure provides a network equipment power supply and a heat dissipation system therefor. The heat dissipation system includes a liquid-cooling heat dissipation device and an air-cooling heat dissipation device. The liquid-cooling heat dissipation device includes a liquid inlet, a liquid outlet, and a liquid-cooling pipe between them, wherein liquid-cooling medium flows inside the liquid-cooling pipe and takes away heat generated by components arranged around the liquid-cooling pipe; The air-cooling heat dissipation device includes an air inlet, an air outlet, and an air-cooling channel between them, wherein airflow passes through the air-cooling channel and takes away heat generated by components arranged around the air-cooling channel.

Abstract: A method, system, and computer program product to aggregate code change requests for a continuous integration pipeline. The method may include receiving a plurality of code change requests (CCRs) for a software product that are to be processed by a continuous integration (CI) pipeline. The method may also include obtaining all functions of the software product tested by all testcases in a testcase set. The method may also include selecting a plurality of groups of testcases from the testcase set, each group of the plurality of groups of testcases corresponding to a CCR from the plurality of CCRs. The method may also include identifying at least two groups of testcases from the plurality of groups of testcases without overlapping code. The method may also include aggregating each CCR that corresponds to the at least two groups of testcases into a single CCR group.

Abstract: A stress measuring structure, including a substrate, a support layer, a material layer, and multiple marks, is provided. The support layer is disposed on the substrate. The material layer is disposed on the support layer. There is a trench exposing the support layer in the material layer. The material layer includes a main body and a cantilever beam. The trench is located between the cantilever beam and the main body and partially separates the cantilever beam from the main body. One end of the cantilever beam is connected to the main body. The marks are located on the main body and the cantilever beam.

Abstract: The application provides a power supply device comprising two input ports disposed at a front end of the power supply device; at least one fan disposed behind the two input ports and two isolated power supplies connected respectively to the corresponding one of the two input ports and disposed behind the two input ports and the at least one fan. Each of the isolated power supplies comprises a main power circuit having at least one module, and each module comprises a PCB and a magnetic element and/or switching devices. The at least one module includes an isolated circuit module comprises a transformer having windings formed by laying copper in the PCB and the magnetic core fixed on the PCB. And at least one fan is configured for heat dissipation of the at least one module.

Abstract: The present disclosure provides a converter CO2—O2 mixed injection smelting method and a fire point area temperature dynamic control method. The method realizes online monitoring through an infrared temperature sensor installed inside an oxygen lance, dynamically adjusts the mixing ratio of CO2 and O2 and the height of the oxygen lance position according to the fire point area temperature changes and process requirements in different smelting stages, so that the secondary smelting system interlockingly and dynamically controls the fire point area temperature and the molten pool heating rate.

Abstract: There is provided a method of dynamic control for a bottom blowing O2—CO2—CaO converter steelmaking process. In the process, O2 is adopted as a top blowing gas, a mixed gas O2+CO2 is adopted as a bottom blowing carrier gas to inject lime powders into the converter from a bottom blowing tuyere. The ingredients of the molten steel in the converter steelmaking process are predicted based on the conservation of matter, in combination with the ingredient data of charged molten iron, the ingredient data of the converter gas in the converter blowing process, and working conditions of the bottom blowing device. The top blowing oxygen amount, the bottom blowing gas ratio and the flow rate of lime powder are dynamically adjusted stage by stage according to requirements for target ingredients at the end point of blowing.

Abstract: A control method for a power factor correction circuit is disclosed. The power factor correction circuit includes a first bridge arm, a second bridge arm, an output capacitor and an active clamp unit. The control method includes steps of providing a first driving waveform to control a main switch, providing a second driving waveform to control an auxiliary switch, and providing a third driving signal to control a fifth switch. A first delay time is between the turning-off time point of the third driving signal and the turning-on time point of the first driving waveform, a second delay time is between the turning-on time point of the first driving waveform and the turning-off time point of the second driving waveform, and a third delay time is between the turning-off time point of the second driving waveform and the turning-on time point of the third driving signal.

Abstract: A magnetic element, a power module and a power conversion system are provided. The magnetic element includes a main body, a plurality of first magnetic posts, a first common magnetic post and a second magnetic post. A first lateral edge and a second lateral edge of the main body are opposite to each other and extended along a first direction. A third lateral edge and a fourth lateral edge of the main body are opposite to each other and extended along a second direction. The plurality of first magnetic posts are disposed on the main body and arranged along the first direction. The first common magnetic post is disposed on the main body and located at the first magnetic posts. The second magnetic post is disposed on the main body and located at the first common magnetic post.

Abstract: The present disclosure provides an antenna module and a mobile terminal. The antenna module includes a dielectric block and a radiation patch. The dielectric block is a polyhedron, the radiation patch is attached to a plurality of surfaces of the dielectric block, and the radiation patch is provided with a feed point and a ground point. The mobile terminal is provided with several antenna modules described above. The antenna module provided in the present disclosure attaches the radiation patch to the plurality of surfaces of the dielectric block with a polyhedral structure, thereby reducing an overall volume of the antenna module while increasing an effective radiation area of the radiation patch and enhancing radiation performance of the antenna module.

Abstract: The present disclosure provides a control method for an AC-DC conversion circuit. The method includes: in an entire load range, acquiring circuit parameter information of the AC-DC conversion circuit; limiting an actual switching frequency or an actual switching period of the AC-DC conversion circuit within a preset working range according to the circuit parameter information. The AC-DC conversion circuit can meet requirements of Total Harmonic Distortion (THD), Power Factor (PF), efficiency and Electromagnetic Interference (EMI) and the like by adjusting the working information of the AC-DC conversion circuit through the preset working range.

Abstract: A charging device, method, and device are provided. The charging device may include a charging circuit that may include at least a first charging module and a second charging module. The charging device may include a switching circuit that may connect the first charging module and the second charging module. The switching circuit may control, in response to normal charging with the first charging module, the first charging module to enter a charging state or may control both the second charging module and the first charging module to enter the charging state, or may control, in response to abnormal charging with the first charging module, the second charging module to enter the charging state.

Abstract: A long-life service method for powder-bottom-injecting converter based on collaborative hot replacement of furnace bottom and bottom purging brick belongs to the field of steelmaking technologies using powder-bottom-injecting converters. According to equipment characteristics, process characteristics, and erosion characteristics of the powder-bottom-injecting converter, the design, arrangement, installation, use, maintenance, and replacement of the bottom purging/powder injection bricks are systematically optimized and improved, a technology of automatically detecting the erosion height of bottom purging bricks is adopted, and hot replacement of bottom purging/powder injection bricks and hot replacement of the converter furnace bottom are used collaboratively, which not only can prolong the service life of a single bottom purging/powder injection brick, but also can greatly prolong the overall life of the powder-bottom-injecting converter from 1000-3000 heats in the prior art to 6000-10000 heats.

Abstract: A full-length screen pipe hole protection device and method with pressurized hole packing in a soft coal seam relates to the field of gas drainage technologies. The device includes a grouting system, a drainage system and a hole fixing system. The grouting system injects a pressurized sealing material into a borehole through a pressure pump to increase a sealing effect of the borehole. The drainage system drains gas in the middle of air holes on metal baffle plates and hole fixing screen pipes through a drainage pipe to increase flowability of gas. The hole fixing system is inside the borehole and fixed with the metal baffle plates, and the hole fixing screen pipes are fixedly connected with each other through fitting mouths and fitting buckles. The device is fixedly mounted in the gas drainage borehole. After hole packing, the drainage pipe is connected with a drainage pump to drain gas.

Abstract: A full-length screen pipe hole protection device and method with pressurized hole packing in a soft coal seam relates to the field of gas drainage technologies. The device includes a grouting system, a drainage system and a hole fixing system. The grouting system injects a pressurized sealing material into a borehole through a pressure pump to increase a sealing effect of the borehole. The drainage system drains gas in the middle of air holes on metal baffle plates and hole fixing screen pipes through a drainage pipe to increase flowability of gas. The hole fixing system is inside the borehole and fixed with the metal baffle plates, and the hole fixing screen pipes are fixedly connected with each other through fitting mouths and fitting buckles. The device is fixedly mounted in the gas drainage borehole. After hole packing, the drainage pipe is connected with a drainage pump to drain gas.

Abstract: Power module includes transformer unit including primary and secondary windings and magnetic core; first and second capacitor units coupled to first terminal of primary winding of transformer unit through first node; first and second external pins respectively coupled to first terminal of first capacitor unit and second terminal of second capacitor unit; first and second switch units coupled to second terminal of primary winding of transformer unit thorough second node; third and fourth external pins respectively coupled to first terminal of first switch unit and second terminal of second switch unit; secondary-side circuit coupled to secondary winding; and fifth and sixth external pins electrically coupled to first and second output terminals of secondary-side circuit, respectively. First external pin is coupled to one of third and fourth external pins selectively.