Abstract: Methods, systems, and apparatus, including computer programs encoded on a computer storage medium, for evaluating interactions with a user interface are disclosed. In one aspect, a method includes identifying a set of mutation events specifying changes to the structure of a user interface that occurred during the user session, and generating user interface states specifying different structures of the user interface throughout the given user session. Based at least in part on the user interface states, playback data that present visual changes of the user interface corresponding to the set of mutation events that occurred during the user session are generated. Session activity data describing user interactions that occurred during the user session are also generated. At least a portion of the playback data and the session activity data are output to a requesting device.

Abstract: An electrical machine has a core that includes stranded magnetically permeable material. The core is elongated to thereby define a lengthwise direction and a profile that is transverse to the lengthwise direction. Coils are wound about the core profile and sequentially disposed along the lengthwise direction. A magnet is adjacent to the core and movable relative to the core.

Abstract: A backpack including dividers that are provided to form a plurality of compartments in a backpack for storing papers, binders, file folders, books, and the like. The dividers can be permanently or detachably secured to the backpack. The dividers can include identification tabs for identifying the compartments. The identification tabs can be color coded or include identifying indicia. The backpack can also include individual closure means for opening and closing the compartment. The individual closure means can include identification tabs for identifying the compartments.

Abstract: An electrical machine includes first and second magnetically permeable parallel cores. Each core is elongated to thereby define a lengthwise direction and first and second core profiles transverse to the lengthwise direction. First coils are wound about the first core profile and sequentially disposed along the length of the first core. Second coils are wound about the second core profile and sequentially disposed along the length of the second core. A multi-pole elongated permanent magnet is parallel with the cores and located between them. The magnet is movable, relative to the cores, in the lengthwise direction.

Abstract: An electrical machine comprises a magnetically permeable ring-shaped core centered on an axis of rotation and having two axially-opposite sides. Coils are wound toroidally about the core and disposed sequentially along the circumferential direction. Each coil includes two side legs extending radially alongside respectively sides of the core. Coil-free spaces exist between adjacent side legs. A bracket has first and second side flanges that are connected by a bridging structure and respectively abut the first and second sides of the coil.

Abstract: An electrical machine includes first and second magnetically permeable parallel cores. Each core is elongated to thereby define a lengthwise direction and first and second core profiles transverse to the lengthwise direction. First coils are wound about the first core profile and sequentially disposed along the length of the first core. Second coils are wound about the second core profile and sequentially disposed along the length of the second core. A multi-pole elongated permanent magnet is parallel with the cores and located between them. The magnet is movable, relative to the cores, in the lengthwise direction.

Abstract: An electrical machine has a core that includes stranded magnetically permeable material. The core is elongated to thereby define a lengthwise direction and a profile that is transverse to the lengthwise direction. Coils are wound about the core profile and sequentially disposed along the lengthwise direction. A magnet is adjacent to the core and movable relative to the core.

Abstract: A method includes the steps of 1) providing a ring-shaped permanent magnet having radially inner and outer surfaces and opposite first and second side surfaces; 2) overmolding a casing material about the magnet to yield a magnet assembly, the casing material comprising a material that contracts as it cools from a molten state and that includes a portion located along the radially outer surface and the first side surface; and 3) mounting the assembly about a rotor shaft.

Abstract: An electrical machine comprises a magnetically permeable ring-shaped core centered on an axis of rotation and having two axially-opposite sides. Coils are wound toroidally about the core and disposed sequentially along the circumferential direction. Each coil includes two side legs extending radially alongside respectively sides of the core. Coil-free spaces exist between adjacent side legs. A bracket has first and second side flanges that are connected by a bridging structure and respectively abut the first and second sides of the coil.

Abstract: An electrical machine comprises a magnetically permeable core. The core is elongated to thereby define a lengthwise direction and a profile that is transverse to the lengthwise direction. Coils are wound about the core profile and sequentially disposed along the lengthwise direction. The core profile has a surface that is bowed outward.

Abstract: An electrical machine comprises a magnetically permeable core. The core is elongated to thereby define a lengthwise direction and a profile that is transverse to the lengthwise direction. Coils are wound about the core profile and sequentially disposed along the lengthwise direction. The core profile has a surface that is bowed outward.

Abstract: A ball joint wheel assembly is disclosed which includes an axle with at least one ball end, to which a wheel is secured. The wheel includes a socket for retaining the ball end, thereby forming a ball joint for supporting the rotation of the wheel. A bore is connected to the socket for receiving the axle and defining a bore wall within the wheel. The bore is substantially conical and has a desired bore angle. The bore wall thereby defines and limits the swivel angle of the wheel.

Abstract: A fan for a vacuum cleaner has a fan housing, motor and impeller. The fan housing has an inlet and outlet. The impeller has a overmolded hub and multiple flexible blades. This flexible blade fan provides better air performance, less noise, better durability, and easier impeller installation than conventional vacuum cleaner fans.

Abstract: A fan for a vacuum cleaner has a fan housing, motor and impeller. The fan housing has an inlet and outlet. The impeller has a one piece hub and multiple flexible blades. This flexible blade fan provides better air performance, less noise, better durability, and easier impeller installation than conventional vacuum cleaner fans.

Abstract: A fan for a vacuum cleaner has a fan housing, motor and impeller. The fan housing has an inlet and outlet. The impeller has a hub and multiple flexible blades, formed of a plurality of strips. This flexible blade fan provides better air performance, less noise, better durability, and easier impeller installation than conventional vacuum cleaner fans.

Abstract: A fan for a vacuum cleaner has a fan housing, motor and impeller. The fan housing has an inlet and outlet. The impeller has a hub and multiple flexible blades. This flexible blade fan provides better air performance, less noise, better durability, and easier impeller installation than conventional vacuum cleaner fans.

Abstract: A device and method for measuring the moisture content of a sample using microwaves is provided. The device includes a power supply for outputting an electrical current, a microwave oscillator electrically connected to the power supply for outputting a microwave signal, and a waveguide placed between the microwave oscillator and the sample. The waveguide has a predetermined length and is constructed from copper. A microwave detector outputs a voltage signal which is related to the intensity of the microwave energy reflected by moisture in the sample. A voltmeter displays a reading of the voltage signal output by the microwave detector. The length of the waveguide is selected to maximize the voltage reading of the voltmeter for a given sample. An enclosure houses the power supply, the microwave oscillator, the waveguide and the microwave detector, and is provided with an opening at which the waveguide is mounted. A sheet of microwave transmissive material covers the opening.

Abstract: An inductive displacement transducer is provided having a two-piece probe assembly capable of being displaced within the hollow interior portion of a coil. The probe assembly comprises a cylindrical rod disposed within a tube. The rod and the tube are each movable with respect to each other and with respect to the coil. The coil is uniformly wound and is connected electrically in parallel with a stable-frequency current-based oscillator which transmits an AC voltage oscillating signal corresponding to the inductance of the coil. A demodulating circuit, which is capable of converting the AC voltage oscillating signal to a DC voltage level, is connected in parallel with the oscillator. In the preferred embodiment, the coil is covered with a shield which is slit along its length. In operation, the two-piece probe assembly is displaced within a hollow portion of the coil such that a change in inductance results when the rod is displaced relative to the tube.

Abstract: An inductive displacement transducer is provided having a probe capable of being displaced within the hollow interior portion of a coil. The coil, which is typically uniformly wound, is connected electrically in parallel with a stable-frequency current-based oscillator which transmits an AC voltage oscillating signal relating to the inductance of the coil. A demodulating circuit, which is capable of converting the AC voltage oscillating signal to a DC voltage level, is connected in parallel with the oscillator. In one preferred embodiment, the coil is covered with a shield which is slit along its length. In operation, the probe is displaced within a hollow portion of the coil such that a change in inductance of the coil results. A corresponding change in the AC voltage amplitude of the signal output of the oscillator is communicated to the demodulating circuit which generates a change in DC voltage level corresponding to the change in the oscillating signal.

Abstract: An inductive transducer for measuring rotary displacement is provided in which the transducer uses a probe capable of being displaced within a hollow interior portion of a partially toroidal coil. The partially toroidal coil, which is typically uniformally wound, is connected in parallel with a stable-frequency current-based oscillator which transmits an AC voltage oscillating signal relating to the inductance of the coil. A demodulating circuit, which is capable of converting the AC voltage oscillating signal to a DC voltage level, is connected in parallel with the oscillator. In one preferred embodiment, the probe is inserted into the hollow interior portion of the partially toroidal coil by way of a pivoting arrangement. In operation, the probe is displaced within the hollow interior portion of the coil such that a change in inductance of the coil results.