Abstract: A method for scheduling cleaning of a photovoltaic (“PV”) system is implemented by a soiling monitoring computer system. The method includes determining a soiling level and a soiling rate for a photovoltaic (PV) system, calculating a cost associated with cleaning the PV system at each of a plurality of possible cleaning times, determining an expected energy output gain associated with cleaning the PV system at each of the plurality of possible times based on the soiling level and the soiling rate, calculating an expected benefit associated with cleaning the PV system at each of the plurality of possible cleaning times based on the expected energy output gain associated with each possible cleaning time, determining a first time of the plurality of possible times when the expected benefit exceeds the cost, and scheduling a cleaning time based on at least the determined first time.

Abstract: A Tug-of-war apparatus for competition and training including at least one frame section supporting a horizontal movable surface including a continuous running belt mounted between rollers on the frame section; at least one stationary upright support means attached to the front of the frame section; at least one pulling rope extending substantially horizontally from the stationary support means; weighing means for determining the weight of the users on the movable surface; and means for determining the distance the movable surface has moved. One of the rollers includes a drive shaft.

Abstract: A method for calibrating irradiance sensors is performed by an irradiance analysis computing device in communication with a memory. The method includes receiving an irradiance estimate representing an expected amount of irradiance, receiving a first irradiance value associated with at least one irradiance sensor, processing the irradiance estimate and the first irradiance value to generate at least one irradiance metric, and determining a condition of said irradiance sensor based at least in part on the at least one irradiance metric.

Abstract: The present disclosure provides systems, tools, and methods for enhancing a measurement of a fluid in a borehole, pipe, conduit and/or the like. The systems, tools, and methods may involve an electromagnetic measurement tool that includes a transmitting antenna configured to transmit electromagnetic energy, a receiving antenna configured to receive the electromagnetic energy, and a metamaterial element comprising a negative refractive index. The metamaterial element may focus the electromagnetic energy. The electromagnetic system may comprise one or more antennas that are disposed adjacent to or in contact with the fluid, electromagnetic energy may be transmitted via the transmitting antenna, and the electromagnetic energy may be received with the receiving antenna to measure a property of the fluid.

Abstract: A droplet generating device for use as part of a continuous inkjet printer comprises a set of channels for providing a composite flow of a first fluid (11) surrounded by a second fluid (12) and an expansion cavity (3) having an entry orifice (2) and an exit orifice (4). The cross sectional area of the cavity is larger than the cross sectional area of either orifice such that the composite flow breaks up to form droplets of the first fluid within the second-fluid within the cavity, the exit orifice also forming a nozzle of an inkjet device, the passage of the droplets of the first fluid through the exit orifice causing the composite jet to break into composite droplets.

Abstract: A method and apparatus for measuring interfacial or surface tension of a first fluid dispersed in a second fluid, the method involving providing at least one substantially spherical droplet or bubble of the first fluid in a flowing stream of the second fluid in a flow channel, followed by passing the flowing stream comprising the droplet or bubble through a constriction in the flow channel, the constriction being sufficiently constricting so as to cause the droplet or bubble to deform away from its substantially spherical shape and measuring and comparing a physical property of the flowing stream both before and after the constriction, wherein the physical property changes as a result of the deformation of the droplet or bubble, and thereby inferring the interfacial or surface tension from the measured physical property.

Abstract: The present disclosure provides systems, tools, and methods for enhancing a measurement of a property of a solid body or fluid. The systems, tools, and methods may involve an electromagnetic measurement tool that includes a transmitter configured to transmit electromagnetic energy, a receiver configured to receive the electromagnetic energy, and a metamaterial element comprising a negative refractive index. The metamaterial element may focus the electromagnetic energy. The electromagnetic tool may be placed adjacent the solid body or fluid, electromagnetic energy may be transmitted via the transmitter, and the electromagnetic energy may be received with the receiver to measure a property of the solid body or fluid.

Abstract: A method and system for determining a rock matrix dielectric permittivity. The method and system use a matching liquid with a temperature dependant permittivity. The matching liquid may be used in an automated and/or downhole system for measuring matrix dielectric permittivity of rock formations.

Abstract: A method and device for periodically perturbing the flow field within a microfluidic device to provide regular droplet formation at high speed.

Abstract: A rippled wafer (90) formed of a convoluted wafer ribbon (80), the rippled wafer (90) having an average of at least 12 turns/cm2, wherein a turn is a change in direction of the wafer ribbon (80) of at least 45°, and a confectionery product comprising such a wafer. Also a confectionery product comprising a rippled wafer (90) formed of a convoluted wafer ribbon (80), wherein the turns are substantially uniformly distributed across the cross section of the rippled wafer, where a turn is a change in direction of the wafer ribbon of at least 45°, and a confectionery product comprising a three-dimensional rippled wafer (90) formed in a single step.

Abstract: A zero-footprint remotely hosted phone application development environment is described. The environment allows a developer to use a standard computer without any specialized software (in some embodiments all that is necessary is a web browser and network access) together with a telephone to develop sophisticated phone applications that use speech recognition and/or touch tone inputs to perform tasks, access web-based information, and/or perform commercial transactions. For example, in preparation for a sales pitch for selling hosting services, a non-programmer can develop a short application appropriate to the target customer. After the pitch, access to the demonstration could be given to the target customer to allow them to more fully develop the application. When the target customer is satisfied with the application, they can have their application live for their actual (as opposed to test users) at a suitable phone number simply by having the hosting provider configure the appropriate access.

Abstract: Systems and methods for analysis of drilling cuttings are described. Complex permittivity is measured of rock cutting samples obtained during drilling operations. The origin of the cuttings is known by flow rate analysis in the drilling system. Various means can be used for rock cutting dielectric measurement. For example, the dielectric measurement can be made by matching the unknown permittivity of the medium to be analyzed to the permittivity of known liquid mixtures by successive saturation and looking for a “zero-contrast” measurement.

Abstract: Interfacial tension between first and second immiscible liquids is determined using a device in which entrance and exit channels are connected by a cavity with wider cross-section. A flow of the first liquid enters the cavity as a jet and breaks into droplets within the cavity. Passage of a droplet through the exit channel feeds back to perturb the jet entering the cavity. An alternating signal applied to a heating element perturbs the incoming jet and is progressively scanned over a frequency range which includes the system's resonant frequency (frequency of droplet formation with no signal to the heating element). A bandwidth of frequency is observed in which the frequency of droplet formation is phase locked to the frequency applied to the heater. The ratio of resonant frequency to this bandwidth is a measurement of the interfacial tension between the two liquids.

Abstract: A method and device for passively periodically perturbing the flow field within a microfluidic device to cause regular droplet formation at high speed.

Abstract: A method for creating composite droplets for use in an ink jet system includes a first fluid (1) brought into contact with a second fluid within a set of channels (5,14). The interface between the fluids is characterized by an interfacial tension. The first fluid forms spaced droplets (8) within the second fluid, the composite of the first and second fluids passing through an orifice (6) to form a jet (9).

Abstract: An inkjet printing system comprising a plurality of static inkjet printing units each comprising at least one inkjet printing head; an ink-receiving element comprising a poorly-absorbing or impermeable substrate; an aqueous inkjet composition which comprises a polymeric compound comprising discrete particles responsive to an external stimulus, and a functional material, which may be incorporated as part of the polymeric particles, the composition having a first rheological state and a different second rheological state in response to a stimulated change in conditions, the first state being associated with a first lower viscosity of the composition, wherein the particles have a first lower volume, and the second state being associated with a second higher viscosity of the composition, wherein the particles have a second higher volume, and of drying the aqueous ink composition only positioned downstream of the plurality of the printing units.

Abstract: A method of creating substantially monodisperse droplets comprising supplying a first fluid (1) and a second immiscible fluid (2) within a set of channels, the second fluid surrounding the first fluid and filling the channels to form a composite jet. The composite jet passes through an entrance channel (4) into a wider cavity (3), where the first fluid breaks into droplets (5), the resulting composite of droplets of the first fluid within the second fluid passing through an exit channel (6). The cross sectional area of the exit channel perpendicular to the flow is smaller than the cross sectional area of the cavity and the passage of a droplet of the first fluid out of the cavity via the exit perturbs the composite flow field within the cavity such that the incoming jet of the first fluid is perturbed.

Abstract: Systems and methods for analysis of drilling cuttings are described. Complex permittivity is measured of rock cutting samples obtained during drilling operations. The origin of the cuttings is known by flow rate analysis in the drilling system. Various means can be used for rock cutting dielectric measurement. For example, the dielectric measurement can be made by matching the unknown permittivity of the medium to be analyzed to the permittivity of known liquid mixtures by successive saturation and looking for a “zero-contrast” measurement.

Abstract: A liquid jet is ejected out of a nozzle, the liquid comprising one or more components, the flow of one or more of said components, the active components, being separated such that the liquid that flows within a boundary layer thickness ?, of the nozzle wall is substantially comprised of a liquid without the active components, the continuous phase, and the said active components flow substantially outside said boundary layer where ? is defined by formula (I): where ? is the continuous phase viscosity in Pa·s, U is the jet velocity in m/s ? is the continuous phase density in kg/m3 and x is the length of the nozzle in m in the direction of flow.

Abstract: The invention provides an aqueous inkjet ink composition comprises a polymeric compound comprising discrete particles responsive to an external stimulus, and a functional material, wherein the functional material may be incorporated as part of the polymeric particles, the particles causing the composition to have a first rheological state and a different second rheological state in response to a stimulated change in conditions, the first rheological state being associated with a first lower viscosity of the composition, wherein the particles have a first lower volume, enabling the composition to pass through an inkjet printhead orifice and the second rheological state being associated with a second higher viscosity of the composition, wherein the particles have a second higher volume, enabling immobilisation of droplets of the composition on a substrate.