Abstract: An online concierge system maintains an item catalog maintaining a hierarchical taxonomy of the items. Using the hierarchical taxonomy, the online concierge system selects a cohort of items. For the cohort, the online concierge system selects an attribute and generates a distribution of values of the attribute across items in the cohort. From the distribution, the online concierge system identifies one or more items having values for the attributes that are outliers. The online concierge system may provide the identified one or more items to users for manual review to identify possible errors in the item catalog. The data regarding whether manual review identified errors is saved by the online converge system for later use as labels to train a machine learning model for detecting errors.

Abstract: The present subject matter relates to systems, devices, and methods for data-driven precision agriculture through close-range remote sensing with a versatile imaging system. This imaging system can be deployed onboard low-flying unmanned aerial vehicles (UAVs) and/or carried by human scouts. Additionally, the present technology stack can include methods for extracting actionable intelligence from the rich datasets acquired by the imaging system, as well as visualization techniques for efficient analysis of the derived data products. In this way, the present systems and methods can help specialty crop growers reduce costs, save resources, and optimize crop yield.

Abstract: A stepper motor control system includes stepper motor error reduction. For example, first and second power switches respectively energize and de-energize a stepper motor coil during each cycle for pulse-width modulating (PWM) the coil current. During a cycle including a zero crossing microstep, a calibrator detects a type of a body diode effect that occurs in the second power switch when the second switch stops de-energization of the coil. A selected offset is adjusted in response to the type of detection of the body diode effect of the second power switch. Adjusting the selected offset controls the trigger time for a comparator for comparing an offset reference voltage to a motor voltage developed in response to the coil current. Progressively adjusting the selected offset over successive cycles compensates for delays of components in the PWM control loop and reduces errors resulting from, for example, process, voltage, and temperature variations.

Abstract: A stepper motor control system includes stepper motor error reduction. For example, first and second power switches respectively energize and de-energize a stepper motor coil during each cycle for pulse-width modulating (PWM) the coil current. During a cycle including a zero crossing microstep, a calibrator detects a type of a body diode effect that occurs in the second power switch when the second switch stops de-energization of the coil. A selected offset is adjusted in response to the type of detection of the body diode effect of the second power switch. Adjusting the selected offset controls the trigger time for a comparator for comparing an offset reference voltage to a motor voltage developed in response to the coil current. Progressively adjusting the selected offset over successive cycles compensates for delays of components in the PWM control loop and reduces errors resulting from, for example, process, voltage, and temperature variations.

Abstract: The present subject matter relates to systems, devices, and methods for data-driven precision agriculture through close-range remote sensing with a versatile imaging system. This imaging system can be deployed onboard low-flying unmanned aerial vehicles (UAVs) and/or carried by human scouts. Additionally, the present technology stack can include methods for extracting actionable intelligence from the rich datasets acquired by the imaging system, as well as visualization techniques for efficient analysis of the derived data products. In this way, the present systems and methods can help specialty crop growers reduce costs, save resources, and optimize crop yield.

Abstract: A method of authenticating an online read right of a digital content includes: receiving an online read first request from a terminal, the first request including first user information, obtaining first right information corresponding to the first user information, generating a first right model, obtaining first certificate information corresponding to the first right model, generating a second request including the first right model and the first certificate information, and authenticating the first certificate information and M function rights in the first right model.

Abstract: The present invention relates to the technical field of computer application, and more particularly to a method for allowing user access, a client, a server, and a system, for solving the problem that when a user accesses a server, it cannot be determined whether the user is allowed to continue accessing the server. The method comprises: a server receiving a type identifier and/or server identifier and user identity information sent from a client, for each application accessed by a login user, the client generating a type identifier and/or server identifier corresponding to the application; the server determining the number of type identifiers and/or server identifiers received for the user according to the user identity information, and determining whether to allow access of the user. The method can solve the problem that when a user accesses a server, it is determined whether the user is allowed to continue accessing the server.

Abstract: A method for updating an authorization of electronic information includes receiving, by an authorization updating server, first information from a user equipment requesting for updating authorization items, wherein the first information includes first identification information and a first list of authorization items requested to be updated, determining a second list of authorization items stored in the authorization updating server that correspond to the first identification information, comparing the first list of authorization items and the second list of authorization items and determining a third list including authorization items that are listed in both the first list and the second list of authorization items, and transmitting the third list of authorization items to the user equipment.

Abstract: A method of authenticating an online read right of a digital content includes: receiving an online read first request from a terminal, the first request including first user information, obtaining first right information corresponding to the first user information, generating a first right model, obtaining first certificate information corresponding to the first right model, generating a second request including the first right model and the first certificate information, and authenticating the first certificate information and M function rights in the first right model.

Abstract: The invention provides a crystallizable glass, a crystallized glass, and manufacturing methods thereof. The crystallizable glass can be crystallized in a short period of time, and can maintain its glass shape and its surface condition during a crystallization process. The crystallized glass has good mechanical strength, an adequate thermal expansion coefficient that allows the crystallized glass to be used as a construction material, less content of alkali-metal oxides, and good chemical durability. The MgO—Al2O3—SiO2-based crystallizable glass and crystallized glass contain, by mass percent, 55.0-65.0% SiO2, 8.0-14.0% Al2O3, 10.0-20.0% MgO, 1.5-6.0% CaO, 1.0-2.2% Li2O, 0.7-3.0% Na2O, 2.5-4.0% K2O, and 1.5-3.0% F.

Abstract: A consecutive molding method for crystallized glass comprises: a process to obtain molten glass by melting glass raw materials; a process to obtain a band-shaped plate glass by roll forming the molten glass; a crystallization process to obtain a band-shaped crystallized glass plate by conducting thermal treatment on the band-shaped plate glass to crystallize it; and a process to cut the band-shaped crystallized glass plate, wherein the crystallization process includes: a process to form crystal nuclei in the band-shaped plate glass by disposing it in the atmosphere of a crystal nucleus-formation temperature and retaining it at the temperature; a process to raise the temperature of the band-shaped plate glass with crystal nuclei to a crystal-growth temperature; a process to retain the band-shaped plate glass with crystal nuclei at the crystal-growth temperature to produce a band-shaped crystallized glass plate; and a process to slowly cool down the band-shaped crystallized glass plate.

Abstract: A consecutive molding method for crystallized glass comprises: a melting process to obtain molten glass by melting glass raw materials; a molding process to obtain a band-shaped plate glass by roll forming the molten glass to become band-shaped; a crystallization process to obtain a band-shaped crystallized glass plate by conducting thermal treatment on the band-shaped plate glass to crystallize it; and a cutting process to cut the band-shaped crystallized glass plate, wherein the crystallization process includes: a temperature-raising process to produce the band-shaped crystallized glass plate by disposing the band-shaped plate glass obtained in the molding process, in the atmosphere of a crystal nucleus-formation temperature and raising the temperature to a crystal-growth temperature or above to grow crystals as well as form crystal nuclei; and a slow-cooling process to slowly cool down the band-shaped crystallized glass plate.

Abstract: The invention provides a crystallizable glass, a crystallized glass, and manufacturing methods thereof. The crystallizable glass can be crystallized in a short period of time, and can maintain its glass shape and its surface condition during a crystallization process. The crystallized glass has good mechanical strength, an adequate thermal expansion coefficient that allows the crystallized glass to be used as a construction material, less content of alkali-metal oxides, and good chemical durability. The MgO—Al2O3—SiO2-based crystallizable glass and crystallized glass contain, by mass percent, 55.0-65.0% SiO2, 8.0-14.0% Al2O3, 10.0-20.0% MgO, 1.5-6.0% CaO, 1.0-2.2% Li2O, 0.7-3.0% Na2O, 2.5-4.0% K2O, and 1.5-3.0% F.