Abstract: Sulfur contaminants, such as elemental sulfur (S8), hydrogen sulfide and other sulfur components in fluids (e.g., air, natural gas, and other gases, as well as water and other liquids) are removed using a silicone-based chemical filter/bath. In one embodiment, a silicone-based chemical filter includes a membrane having a cross-linked silicone that is a reaction product of an olefin and a polyhydrosiloxane. For example, sulfur contaminants in air may be removed by passing the air through the membrane before the air enters a data center or other facility housing computer systems. In another embodiment, a silicone-based chemical bath includes a housing having an inlet port, an outlet port, and a chamber containing a silicone oil. For example, sulfur contaminants in air may be removed by passing the air through the silicone oil in the chamber before the air enters a data center or other facility housing computer systems.

Abstract: A system for making a personalized malt-based beverage may comprise at least one packaged base liquid and at least one separately packaged flavor ingredient. The at least one packaged base liquid may comprise at least about 0.1% wt ethyl alcohol, at least about 3% wt malt extract solids, and a carbon dioxide level between about zero grams per liter and about 1.5 grams per liter. The separately packaged flavor ingredient may comprise a dry ingredient.

Abstract: A beverage carbonation system, container, carbonator and method for carbonating a beverage are provided. The beverage carbonation system has a container that is removably engageable with a carbonator. The container has a container outlet valve and a container inlet valve that are fluidly engageable with a carbonator outlet port and carbonator inlet port, respectively. At least one pump transfers liquid and carbon dioxide gas between a container chamber and a carbonation chamber when the container is engaged with the carbonator, thereby carbonating the liquid. When the container is disengaged from the carbonator, the container outlet valve and the container inlet valve are closed to fluidly seal the container containing the carbonated liquid.

Abstract: According to one specific embodiment, an oxygen humidifier includes a container that defines an interior space. The oxygen humidifier also includes a top portion that is permanently coupled to the container. The top portion includes an opening for accessing the interior space of the container. The humidifier further includes a lid portion that is movably coupled to the top portion. The lid portion is configured to move between a closed configuration and an open configuration. In the closed configuration, the lid portion seals the opening, and in the open configuration, the lid portion allows access to the interior space through the opening. The oxygen humidifier additionally includes an oxygen diffuser positioned within the interior space.

Abstract: The subject of the invention is a diffuser for saturation of water with gas, comprising a diffusion element (1) for diffusing the gas run through the diffuser, wherein the diffusion element (1) is made of charcoal. The invention also refers to a set for saturating water with gas, as well as a method for saturation of water with gas, and the use of charcoal as a diffusion element.

Abstract: A treatment plant for waste water treatment, including a circulation tank, which is arranged to accommodate waste water up to a predetermined filling height, and at least one aerator section arranged at the bottom of the circulation tank, which aerator section is arranged to supply gas bubbles to the waste water, the circulation tank having a predetermined direction of flow along which the waste water is arranged to flow. The treatment plant includes a partition wall arranged transversely to the circulation tank downstream the aerator section, which partition wall has an upper end that in the vertical direction is situated at a height that is lower than 25% of the above-mentioned filling height.

Abstract: A mixing vessel (10) for containing a liquid, comprises a chamber having a lower chamber portion and an upper chamber portion wider than the lower portion, gas inlet means (14) for supplying gas to the lower portion and means for redirecting rising gas (24), such that, in use, rising gas in the form of bubbles, initially rises substantially vertically and is redirected in a substantially horizontal direction by the means for redirecting rising gas.

Abstract: A vessel for cooling syngas comprising a syngas collection chamber and a quench chamber, wherein the syngas collection chamber has a syngas outlet which is fluidly connected with the quench chamber via a tubular diptube, wherein the syngas outlet comprises of a tubular part having a diameter which is smaller than the diameter of the tubular diptube and is co-axial with the diptube, and wherein the tubular part terminates at a point within the diptube such that an annular space is formed between the tubular part and the diptube, and wherein in the annular space a discharge conduit for a liquid water is present having a discharge opening located such to direct the liquid water along the inner wall of the diptube.

Abstract: The present invention is a container having a diptube inlet, at least one baffle disc positioned between the outlet of the diptube and the outlet of the container to provide a narrow annular space between the baffle disc and the sidewall of the container to prevent liquid droplets from entering the outlet to the container and the inner surface of the container sidewall and an annular, radially inward projecting deflector ledge on the sidewall, proximate the baffle disc. The present invention is also a process of delivering a chemical precursor from a container having the above structure. Liquid and vapor delivery are both contemplated.

Abstract: A refrigerator includes a carbonated water tank in which carbonated water is stored; a water level sensor sensing a water level of carbonated water stored in the carbonated water tank; a water tank supplying filtered water to the carbonated water tank; a carbon dioxide cylinder supplying carbon dioxide to the carbonated water tank; and a controller, if the water level of carbonated water sensed by the water level sensor is less than or equal to a predetermined minimum water level, supplying the filtered water to the carbonated water tank, and if supply of the filtered water is completed, supplying the carbon dioxide to the carbonated water tank so as to produce the carbonated water. If the carbonated water is discharged, the controller controls the water level sensor to sense the water lever of the carbonated water stored in the carbonated water tank.

Abstract: A gas diffuser including a grid of aeration pipes spaced apart and in parallel alignment within a horizontal plane is provided. The aeration pipes have improved discharge hole placement along their lengths and around their circumferences to provide improved performance and reduced fouling of membrane filtration systems associated therewith.

Abstract: A membrane for use in an air diffuser. The membrane includes a nub with a perforation. The nub and perforation and arranged and sized to create smaller bubbles of gas in a liquid column above the membrane.

Abstract: Apparatus for evaporating waste water having chemicals therein which cause foaming comprises a holding tank having an inlet for receiving waste water, one or more submerged combustion chambers with burners suspended within the holding tank, and, one or more foam skimming weirs located in an upper portion of the holding tank, the one or more foam skimming weirs defining one or more foam collection zones.

Abstract: Apparatus for evaporating waste water having dissolved solids therein comprising a holding tank having an inlet for receiving waste water, a submerged combustion chamber with burner suspended within the holding tank, the submerged combustion chamber having a plurality of vertical slots defined therein near a bottom thereof which span a substantial portion of a height of the submerged combustion chamber, a blower connected to provide air under positive pressure to the burner, and, a vent stack coupled to an upper portion of the holding tank for allowing water vapor to exit the holding tank.

Abstract: An automated frothing assembly. The automated frothing assembly has a wand module that includes an elongate member having an inlet, one or more outlets, and a fluid passageway extending between and in fluid communication with the inlet and the plurality of outlets. At least one of the one or more outlets extends parallel to a vertical plane that includes the centerline of the elongate member and at an acute angle relative to a horizontal plane that is perpendicular to both the vertical plane and the centerline of the elongate member. The assembly further includes an actuator configured to be operatively coupled to the wand module and to drive the movement of at least a portion of the wand module along an axis, and an electronic controller configured to be electrically coupled to the actuator and to control the operation of the actuator to control the movement of the wand module.

Abstract: An auxiliary sour gas treatment system for treating a stream of sour gas during a time wherein a primary gas treatment facility is unavailable, malfunctioning, inadequate or inoperable. The auxiliary sour gas treatment system comprises a lean solvent storage system to store an appreciable volume of a regenerable lean solvent available on demand. A scrubber to treat an influent supply of the sour gas by contacting the sour gas and the lean solvent which chemically or physically binds the contaminants in the sour gas resulting in a cleaned gas suitable for disposal or use as a fuel, and the solvent in an enriched state that contains the removed contaminants. The enriched solvent resulting from treatment may be stored indefinitely in a rich solvent storage system and then regenerated at any convenient time and at any convenient rate or place to remove the contaminants from the rich solvent.

Abstract: A multi-disc air diffuser according to the present invention comprises a bolt having a vent groove formed in a longitudinal direction thereof; a plurality of discs, each of the discs having a bolt joint section to be passed through the bolt, an air room for holding the air supplied through the vent groove, and a nozzle section having a plurality of nozzles which are arranged in an end part of the air room at a regular size and intervals, wherein the lower surface of each of the discs is more than the upper surface thereof and the outer circumference surface of each of the discs is formed to be inclined; and a backflow prevention section for joining to an end part of the bolt to adhere closely the discs to one another, connecting the vent groove to an air supply pipe, and having a check valve to prevent the air flowing backward from the vent groove to the air supply pipe.

Abstract: A refrigerator may include a carbonated water tank in which carbonated water is stored; a water tank supplying filtered water to the carbonated water tank; a carbon dioxide cylinder supplying carbon dioxide to the carbonated water tank; a dispenser discharging the carbonated water or the filtered water; and a controller, if the filtered water is supplied to the carbonated water tank and supply of the filtered water is completed, supplying the carbon dioxide to the carbonated water tank so as to produce the carbonated water, wherein the controller stops producing the carbonated water if a discharge instruction of the filtered water is input from a user or if a door of the refrigerator is opened while the carbonated water is produced.

Abstract: Provided is a refrigerator including: a carbonated water tank in which carbonated water is stored; a water tank supplying filtered water to the carbonated water tank; a carbon dioxide cylinder supplying carbon dioxide to the carbonated water tank; and a controller, if the water level of carbonated water sensed by a water level sensor is less than or equal to a predetermined minimum water level, supplying the filtered water to the carbonated water tank, and if supply of the filtered water is completed, supplying the carbon dioxide to the carbonated water tank so as to produce the carbonated water. If it is expected that the storage amount of the carbonated water is reduced or the user won't use the carbonated water for a while, carbonated water is automatically produced so that the user is not required to wait while the carbonate water is produced.

Abstract: A refrigerator is disclosed. The refrigerator includes a body, a storage chamber defined in the body while having an opened front side, a door to open or close the opened front side of the storage chamber, a water tank to store clean water, a carbonated water production module mounted to a back surface of the door, the carbonated water production module including a carbon dioxide gas cylinder stored with carbon dioxide gas, a carbonated water tank to produce carbonated water through mixing of the clean water with the carbon dioxide gas, and a module support to support a bottom of the carbonated water tank, and a water leakage sensor disposed on the module support, to sense water leakage occurring at the carbonated water production module. Through this configuration, it is possible to sense water leakage, and thus to minimize damage caused by water leakage.

Abstract: A refrigerator is disclosed. The refrigerator includes a body, a storage chamber defined in the body while having an opened front side, a door to open or close the opened front side of the storage chamber, a water tank to store clean water, a carbonated water production module mounted to a back surface of the door, the carbonated water production module including a carbon dioxide gas cylinder stored with carbon dioxide gas, a carbonated water tank to produce carbonated water through mixing of the clean water with the carbon dioxide gas, and a gas regulator to adjust a pressure of the carbon dioxide gas flowing from the carbon dioxide gas cylinder to the carbonated water tank, and a safety device to selectively move the carbon dioxide gas cylinder toward or away from the gas regulator, thereby coupling or separating the carbon dioxide gas cylinder to or from the gas regulator.

Abstract: A refrigerator is disclosed. The refrigerator includes a body, a carbonated water tank to produce carbonated water through mixing of clean water with carbon dioxide gas, a sensor unit inserted, at at least a portion thereof, into the carbonated water tank, to sense an internal state of the carbonated water tank, and a holding unit disposed at one side of the carbonated water tank while holding the sensor unit in a fixed state. Through this configuration, it is possible to achieve easy coupling of the sensor unit and lines to the carbonated water tank while preventing water leakage even when the internal pressure of the carbonated water tank is high.

Abstract: A liquid aeration system comprising: an intermittent liquid feeding means (10) located at an upstream position for receiving liquid from a liquid resource; a liquid storage means (20) located at an downstream position for receiving the liquid from the intermittent liquid feeding means (10) quantitatively and intermittently; and a pipe (30) connected between the intermittent liquid feeding means (10) and the liquid storage means (20), the outlet of which is located below the liquid surface of the liquid storage means (20), such that the liquid can flow from the intermittent liquid feeding means (10) through the pipe (30) into the liquid storage means (20) intermittently and quantitatively using the liquid level difference between the upstream position and the downstream position, so as to inject the air existed in the pipe (30) into the liquid in the liquid storage means (20).

Abstract: A reservoir evaporation system for evaporating fluid from an open reservoir of effluent containing a contaminant includes a fluid evaporator, an air pump, and an air supply conduit functionally connecting the fluid evaporator with the air pump. The fluid evaporator includes a vessel adapted to be positioned in an operative position partially submerged on the top surface of the effluent in the reservoir with a lower chamber submerged in the effluent and an upper chamber extending above the top surface of the effluent. In operation, air from the air pump mixes with the effluent inside the fluid evaporator and subsequently is discharged through exhaust openings. A fluid discharge pipe can also simultaneously discharge aerated effluent back down into the reservoir. Fluid is thereby separated from the effluent in the lower chamber by evaporation in a controlled manner that minimizes spread of contaminants to surrounding environments by wind.

Abstract: A compact and portable liquid concentrator and contaminant scrubber includes a gas inlet, a gas exit and a flow corridor connecting the gas inlet and the gas exit, wherein the flow corridor includes a narrowed portion that accelerates the gas through the flow corridor. A liquid inlet injects liquid into the gas stream at a point prior to the narrowed portion so that the gas-liquid mixture is thoroughly mixed within the flow corridor, causing a portion of the liquid to be evaporated. A demister or fluid scrubber downstream of the narrowed portion removes entrained liquid droplets from the gas stream and re-circulates the removed liquid to the liquid inlet through a re-circulating circuit. A reagent may be mixed with the liquid to react with contaminants in the liquid.

Abstract: Provided is a system for dissolving gas into liquid contained within a body. The system may include a tubular body extending between a bottom end and a top end, a gas diffuser coupleable to a gas source and configured for discharging gas bubbles into the tubular body, and a liquid pump for propelling liquid within the tubular body in a downwards direction, against uprising gas bubbles, where the liquid egresses at the bottom end of the tubular body.

Abstract: A buoyant force pump and surge apparatus is disclosed. A material which is buoyant relative to a non-solid material is used to cause a movable surface to move thereby causing the non-solid material to be pumped in surges. One use of the device is to create water surges in aquariums through the use of conventional low pressure, low volume air pumps and without the need for mechanical pumps or control electronics. A second use of the device is to move non-solid material in hazardous conditions.

Abstract: A system and method for processing impure water is achieved by using ozone for the separation and removal of certain contaminants and for further purification of the water. According to one embodiment, a gas comprised of ozone and air is injected into the impure water. The gas is converted to bubbles which are used as a flotation reagent while the ozone portion of the gas provides for the disinfection and deodorization of the liquid. The impure water is constantly supplied into an upper portion of a working volume or column of fluid contained within a processing unit. At the same time the gas is supplied into the bottom part of the same fluid column through one or more diffusers. Due to their porosity the diffusers generate the bubbles of this ozone-based gas so that each bubble has a predetermined size.

Abstract: A micro bubble generating system includes a shell having a well for retaining a first liquid to immerse an object. A micro bubble apparatus is provide to the shell for providing a pressurized mixture of a second liquid and a dissolved gas into the well so as to create a plurality of micro bubbles within the first liquid for engaging the object.

Abstract: A mixing bag for use in bioprocessing in which a fluid is received and agitated using an internal fluid-agitating element driven by an external motive device is disclosed. The bag may include an integral sparger and sensor receiver. Related methods are also disclosed.

Abstract: A system for mixing and mixing processes and structures are disclosed. In addition a nozzle used for mixing is disclosed.

Abstract: A disposable mixing vessel comprising a flexible container, a centrally disposed shaft having first and second ends with one or more impellers thereon and a magnetic element associated with a first shaft end, a first flange adapted to rotatably engage the first shaft end and a second flange adapted to rotatably engage the second shaft end.

Abstract: A system for carbonating a personalized beverage may comprise a base container including at least one sidewall defining a liquid storage area, and a carbon dioxide storage member configured to be sealingly coupled to said base container. The system may further comprise a carbon dioxide cartridge configured to selectively release carbon dioxide when engaged with said carbon dioxide storage member, and wherein said carbon dioxide storage member further comprises a pressure regulator configured to, when actuated, release the said carbon dioxide from said carbon dioxide cartridge at a rate configured to carbonate a beverage within said liquid storage over a period of time greater than 6 hours and less than 36 hours.

Abstract: The integrated aeration system utilizes a water pump for aeration. Ambient air/gas is entrained by a circulating water jet induced by the pump. The circulating water jet enters a sealed tank. The entrained gas is broken into bubbles after the impingement between the jet and a receiving pool occurs, aerating the receiving pool by water jet spray. The entrained gas/air builds up headspace pressure above the water pool, the headspace pressure being measured by a pressure gauge. The trapped air above the water pool is released when the headspace pressure increases to reach a desired value to aerate a separate tank/container as a diffused aeration or any other aeration process.

Abstract: A system & Method for Preventing Scaling in a Flue Gas Desulphurization System is provided. The system includes an injector configured to direct a barrier fluid toward a surface that is otherwise susceptible to scaling when it comes in contact with super-saturated alkaline solutions such as slurry used to capture CO2 from a flue gas stream.

Abstract: A method of scrubbing flue gas includes introducing flue gas comprising an acidic gas through an inlet into a tower; spraying an acid-absorptive fluid into the tower such that the acid-absorptive fluid contacts the flue gas; accumulating the acid-absorptive fluid in a recycle tank portion of the tower; and introducing an oxygen-containing gas into the acid-absorptive fluid in the recycle tank portion of the tower, wherein the oxygen-containing gas is introduced through at least one opening of an aerator, each of the at least one openings are positioned to release the oxygen-containing gas at least at a distance greater than or equal to a predetermined radial distance from the flue gas inlet, the predetermined radial distance being equal to at least 10% of a diameter of the recycle tank portion of the tower.

Abstract: A bubble generating system is provided for use with a gas supply and a container having liquid therein. The gas supply can supply a flow of gas. The bubble generating system includes a gas provider, a first bubble generator and a second bubble generator. The gas provider has an input port, a first output port and a second output port, wherein input portion can connect to the gas supply. Each bubble generator has an inlet and an outlet and is connected to the gas provider. The first bubble generator is arranged to output the first portion of the flow of gas in a first direction. The second bubble generator is arranged to output the second portion of the flow of gas in a second direction, wherein the first direction is different from the second direction.

Abstract: A submersible aeration pump includes a motor housing, an air inlet conduit carried by the motor housing, a pump motor in the motor housing, a rotatable armature drivingly engaged by the pump motor and disposed in air communication with the air inlet conduit and at least one air discharge conduit carried by and disposed in air communication with the armature. Air is drawn from the air inlet conduit, through at least a portion of the armature and is discharged from the at least one air discharge conduit, respectively, by centrifugal force responsive to operation of the pump motor.

Abstract: A micro bubble generating system includes a shell having a well for retaining a first liquid to immerse an object. A micro bubble apparatus is provide to the shell for providing a pressurized mixture of a second liquid and a dissolved gas into the well so as to create a plurality of micro bubbles within the first liquid for engaging the object. One method of using micro bubbles includes providing a fluid mixture, including a saturated gas, to a fluid chamber connected a fitting; and producing a plurality of micro bubbles into a fluid. Another method of using micro bubbles includes providing a fluid mixture, including a saturated gas, into an air entrapment chamber; and producing a plurality of micro bubbles into a fluid.

Abstract: The anchored aerator has a non-buoyant sunken base and a plurality of rigid guide columns extending upward therefrom. A toroidal float is captured between the guide columns, and rises and descends with changes in water level. A down tube passes through the center of the float. A diffuser having a number of radially extending diffuser pipes is installed at the lower end of the down tube. Air is supplied from a remote source, either land-based or based upon a floating vessel. The remote source may supply air to more than one aerator. An air supply line extends from the remote air source to each aerator. Each supply line is supported by one or more rigid columns anchored into the floor of the body of water. The primary aerator structure floats to hold the aerator at a constant level, and is held in position by restraining cables.

Abstract: A liquid evaporation system for evaporating clean water from a reservoir of wastewater includes a liquid evaporator to evaporate and separate water vapor from the wastewater in a confined space, an air blower to supply air to the liquid evaporator, and a wastewater heating system arranged to collect heat to heat the wastewater in the reservoir.

Abstract: An aeration cartridge (10) within an outer vessel, the aeration cartridge (10) comprising a tube (18) constructed from two or more longitudinally joined cylindrical sections (20), wherein respective ends of the cylindrical sections (20) are shaped so that when they are joined together, at least one slot (24) passing from an inner surface of the tube (18) to an outer surface of the tube (18) is created at the join, and wherein the outer vessel is capable of being connected to a high pressure gas supply.

Abstract: Methods, systems, and/or apparatuses for treating wastewater produced at a thermoelectric power plant, other industrial plants, and/or other industrial sources are disclosed. The wastewater is directed through a wastewater concentrator including a direct contact adiabatic concentration system. A stream of hot feed gases is directed through the wastewater concentrator. The wastewater concentrator mixes the hot feed gases directly with the wastewater and evaporates water vapor from the wastewater. The wastewater concentrator separates the water vapor from remaining concentrated wastewater. A contained air-water interface liquid evaporator may be arranged to pre-process the wastewater before being treated by the wastewater concentrator.

Abstract: A micro bubble generating system includes a shell having a well for retaining a first liquid to immerse an object. A micro bubble apparatus is provide to the shell for providing a pressurized mixture of a second liquid and a dissolved gas into the well so as to create a plurality of micro bubbles within the first liquid for engaging the object. A micro bubble generating apparatus may include a housing body having a first fluid passage for a pressurized mixture of a liquid and a dissolved gas in a direction towards a fluid flow. An orifice member can be releasably engaged with the housing body and the orifice member may have a second fluid passage being disposed therein; and the second fluid passage being disposed at an angle with respect to the first fluid passage for generating a plurality of micro bubbles from the mixture; and an opening in the housing body for releasing the plurality of micro bubbles.

Abstract: A fine bubble diffusing tube that can generate fine bubbles evenly and uniformly even when the diffusing tube has a long length, a fine bubble diffusing device using such a tube and a submerged membrane separation apparatus are produced. The fine bubble diffusing tube is provided with a cylindrical supporting tube 1, and an elastic sheet 2 with fine slits formed therein, with the elastic sheet 2 being placed to cover the outer circumference of the supporting tube 1, so that, upon supplying a gas to a space between the elastic sheet 2 and the supporting tube 1, the fine slits of the elastic sheet 2 are opened to generate fine bubbles, and the supporting tube 1 has a length L of 1000 mm or more in the longitudinal direction, with gas supply units 4 serving as gas flow inlets being attached to the two ends of the supporting tube.

Abstract: Sulfur contaminants, such as elemental sulfur (S8), hydrogen sulfide and other sulfur components in fluids (e.g., air, natural gas, and other gases, as well as water and other liquids) are removed using a silicone-based chemical filter/bath. In one embodiment, a silicone-based chemical filter includes a membrane having a cross-linked silicone that is a reaction product of an olefin and a polyhydrosiloxane. For example, sulfur contaminants in air may be removed by passing the air through the membrane before the air enters a data center or other facility housing computer systems. In another embodiment, a silicone-based chemical bath includes a housing having an inlet port, an outlet port, and a chamber containing a silicone oil. For example, sulfur contaminants in air may be removed by passing the air through the silicone oil in the chamber before the air enters a data center or other facility housing computer systems.

Abstract: A mixing bag for use in bioprocessing in which a fluid is received and agitated using an internal fluid-agitating element driven by an external motive device is disclosed. The bag may include an integral sparger and sensor receiver. Related methods are also disclosed.

Abstract: A system & Method for Preventing Scaling in a Flue Gas Desulphurization System is provided. The system includes an injector configured to direct a barrier fluid toward a surface that is otherwise susceptible to scaling when it comes in contact with super-saturated alkaline solutions such as slurry used to capture CO2 from a flue gas stream.

Abstract: Water circulation systems with air stripping arrangements to treat and remove undesirable disinfectant byproducts from potable water in municipal water tanks, ponds, and other bodies of water. The systems include a flotation platform, dish, draft tube, and an impeller to draw water from the depths of the tank up through the draft tube to be discharged outwardly of the dish to create a primary circulation pattern and an induced, inner or secondary circulation pattern. Each system additionally includes an air stripping arrangement positioned adjacent and about the upper portion of the draft tube and adjacent an upper portion of the secondary flow. The air stripping arrangement includes a plurality of submerged sets of air manifolds wherein pressurized air is supplied to the air manifolds and driven out of them in bubbles to create a treatment zone immediately above each set of manifolds.

Abstract: A heater unit is adapted to determine if a humidification chamber thermally coupled to a hot plate of the heater unit is effectively dry based on determining a thermal response of a hot plate of the heater unit. Also, the activation period during which the hot plate is being heated is adjusted toward an optimum period by adjusting the energization or power level to the heater element thereof in relation to the duration of a prior activation period. Further, the air flow rate of gas through the humidification chamber may be estimated based on a temperature of the hot plate determined in predetermined relationship to the beginning of an activation period.