Abstract: Hydrocarbon wells including gas lift valves and methods of providing gas lift in a hydrocarbon well. The hydrocarbon wells include a wellbore extending within a subsurface region and a downhole tubular extending within the wellbore. The downhole tubular defines a tubular conduit, and the wellbore and the downhole tubular define an annular space therebetween. The hydrocarbon wells also include a lift gas supply system configured to provide a lift gas stream to the annular space and a closure material supply system configured to provide a closure material stream to the annular space. The hydrocarbon wells further includes a gas lift valve operatively attached to the downhole tubular. The gas lift valve includes a lift gas injection conduit and an actuation mechanism. The actuation mechanism selectively transitions to a closed state responsive to contact with the closure material. The methods include methods of operating the hydrocarbon wells.

Abstract: A processor-implemented response inference method and apparatus are disclosed. The response inference apparatus receives an input, generates a latent variable vector in a latent variable region space by encoding the input, generates a validation vector with a predetermined phase difference from the latent variable vector, generates an output response by decoding the latent variable vector, generates a validation response by decoding the validation vector, and validates the output response by comparing the output response to the validation response.

Abstract: New/fresh catalyst is added to a dehydrogenation unit and aged catalyst is removed from the dehydrogenation unit on a continuous or semi-continuous basis while the dehydrogenation unit is in operation. The conversion achieved by the higher activity catalyst results in the production rate of olefin product being maintained at near start-of-run production for longer, with a slower rate of decline. The higher activity catalyst extends run time, reduces feed consumption for each unit of olefin product, and minimizes fresh catalyst expenses.

Abstract: Provided is a method and apparatus for managing failure modes for condition based maintenance in marine resource production equipment.

Abstract: A robot control system detects a position and a direction of each user by a plurality of range image sensors provided in an exhibition hall. A central controller records an inspection action after a user attends the exhibition hall until the user leaves to generate an inspection action table. When the user attends again, the central controller reads a history of inspection action from the inspection action table. Then, the central controller chooses from an utterance content table an utterance content containing a phrase that mentions the inspection action included in the history at a time of last time attendance, determines the utterance content, and makes a robot output the determined utterance content to the user.

Abstract: A controller performs multiple regression analysis using an optimum chemical injection rate as a target variable and using one or more water quality indices of a raw water as explanatory variables and thereby derives a calculation formula for a basic chemical injection rate corresponding to the water quality indices. Next, the controller calculates the basic chemical injection rate corresponding to the water quality indices by substituting the measured values of the water quality indices of the raw water into the calculation formula. Then, the controller corrects the basic chemical injection rate based on a measured value of the water quality index of the treated water, thereby newly calculates a chemical injection rate, and outputs the newly calculated chemical injection rate as a control factor for a chemical injection pump while supplying the newly calculated chemical injection rate to calculation of the optimum chemical injection rate.

Abstract: The present invention provides novel techniques for controlling the balance between energy usage and biofuels dehydration between a distillation process unit and molecular sieves with model predictive control technology. In particular, the present techniques are presented in the context of biofuel production, wherein control of the balance between energy usage and water removal in biofuel production may be optimized. However, the present techniques may also be applied to any other suitable applications, such as liquor processing, where energy may be used to remove water from the liquor.

Abstract: A chemical injection system includes a pump in fluid communication with a chemical reservoir and a pipeline; a motor coupled to the pump and adapted to drive the pump to transfer a chemical fluid from the reservoir to the pipeline; a motor controller electrically coupled to a power module and the motor and adapted to adjust a rotational speed of the motor; and a central controller communicably coupled to the motor controller and a remote computing device. The controller includes a translator adapted to receive a signal from the remote computing device in a first communication protocol and translate the signal from the remote computing device to a command in a second communication protocol distinct from the first communication protocol, where the command is operable to adjust the motor controller to adjust the rotational speed of the motor.

Abstract: Embodiments of the present invention generally relate to temperature control of a reactor using probability distribution of temperature measurements. In one embodiment, a method of controlling a temperature of a chemical reaction includes injecting a reactant stream into a reactor and through a catalyst bed of the reactor. The reactant stream includes a hydrocarbon and oxygen. Injection of the reactant stream into the catalyst bed causes an exothermic chemical reaction. The method further includes circulating a coolant through the reactor, thereby removing heat from the catalyst bed. The method further includes measuring temperature at a plurality of locations in the catalyst bed. The method further includes calculating a fraction of the catalyst bed greater than a predetermined maximum temperature limit using a probability distribution generated using the temperature measurements.

Abstract: The method and apparatus are used to determine class, grade and properties of fuel samples, regardless of ambient, instrument, or sample temperature, using mathematical correlations between fuel class, grade and properties and their spectra developed from a database of samples with measured properties and spectra. The ability to measure a fuel sample using the present method and apparatus is useful in identifying unknown fuel samples, determining suitability in equipment, and monitoring and controlling fuel processes, such as blending operations, distillation, and synthesis.

Abstract: The present invention concerns a method of providing advisory controls for a desalter system. The method allows a user to continuously monitor performance of the desalter system, to continuously monitor position of the emulsion band (or rag layer), to control the emulsion band using demulsifiers, and to recommend to users how to maintain optimal pressure drop at the mix valve of the desalter system. This is achieved by using a first principles based model combined with an ultra-sound sensor. The ultra-sound sensor measures the position, quality and size of the emulsion band. The first principles based model takes into account the geometry of the desalter system, physical properties of the crude oil and water, as well as the operating conditions. Thus, the method provides users with sensing of an emulsion layer through ultrasound measurements and also gives recommendations on appropriate corrective actions to be initiated during upsets.

Abstract: Disclosed herein are systems and methods for automated real-time monitoring and controlling desalting in a crude distillation unit. Crude oil and wash water are mixed by a pressure drop across a mix valve, thereby forming a crude oil/water phase stream. The crude oil/water phase stream is supplied into a desalter vessel, whereupon an emulsion forms at an interface between the crude oil and the water phase. The crude oil/water phase stream is contacted with a dosage of an emulsion breaker in an applied electric field. At least one property associated with the emulsion is measured using an emulsion level indicator. A total chlorine and a water percentage of the crude oil are measured. At least one of the pressure drop and the dosage of the emulsion breaker is adjusted substantially in real time in response to at least one of the measured properties, total chlorine, and water percentage.

Abstract: The present invention provides novel techniques for optimizing throughput and yield using model predictive control techniques. In particular, the present techniques are presented in the context of biofuel production, wherein the trade off between yields of biofuel production and overall system throughput may be optimized. However, the present techniques may also be applied to any other suitable applications where a batch process of the system may affect a change in a property of the produced product, such as liquor processing.

Abstract: A control system for optimizing an oxy-fuel power plant comprises an optimizer in communication with the oxy-fuel power plant; the oxy-fuel power plant being operative to recycle carbon dioxide from a flue gas stream to a boiler; a control platform; the control platform being operative to control the oxy-fuel power plant; and a simulator; the simulator being operative to simulate performance of the oxy-fuel power plant.

Abstract: One or more computer implemented systems for continuously processing used oils are provided. The system can include a feedstock tank containing feedstock. The feedstock tank can have a sparger and a level sensor. The feedstock tank can be in fluid communication with a first pump, a first filter, a heater, a second filter, first flow meter, a primary nozzle, a secondary nozzle, a motionless inline static mixer, and a first reactor.

Abstract: Embodiments of the invention provide an advanced control system for steam hydrocarbon reformer furnaces, especially steam methane reformer furnaces. As described herein, the advanced control system may improve the control quality and efficiency of adjusting steam hydrocarbon reformer furnaces operating coefficients. As a result, the steam hydrocarbon reformer furnace operations become more stable, resulting in energy savings and improved furnace yield.

Abstract: A method for monitoring a control of a parameter of one or more devices or systems in an oil or gas production site includes receiving process data, the process data being a result of the control of the parameter of the one or more devices or systems in the production site; smoothing the process data using a polynomial filter while preserving features of the process data to obtain smoothed data; and applying a pattern recognition algorithm to the smoothed data to determine whether there is a malfunction condition in the one or more devices or systems.

Abstract: The present invention is a self-powered method for conversion of disposable hydrocarbons into diesel and heating oil fuels and conversion of biomass into biodiesel fuel. The method is operated using a feedstock tank, a preparation tank for first stage warming of the feedstock, a first heat exchanger to separate out water as steam and light ends, a stack to vent steam to the atmosphere, a second heat extension to raise the temperature to the necessary for processing the feedstock in a cracking kettle, a fume incinerator burning the light ends to generate heat for the first and second heat exchangers, a distillation column to process the gases from the cracking kettle, a condenser to convert gas to liquid #2 diesel fuel, a filter and chiller unit and storage tanks to hold the fuels and residuals. The method uses retained heat in the residuals to preheat the feedstock to save energy.

Abstract: Inventive systems and methods for satisfying demands of fuel having desired properties (e.g., a desired value of higher heating value on a dry basis) are described. The systems and methods of the present invention ensure production of fuel having desired properties by correlating fuel properties with certain process parameters. These parameters are relevant to the process of producing fuel from biomass. Processing regimes for certain values of parameters that provide increased throughput of fuel production are identified.

Abstract: The present invention concerns a method of providing advisory controls for a desalter system. The method allows a user to continuously monitor performance of the desalter system, to continuously monitor position of the emulsion band (or rag layer), to control the emulsion band using demulsifiers, and to recommend to users how to maintain optimal pressure drop at the mix valve of the desalter system. This is achieved by using a first principles based model combined with an ultra-sound sensor. The ultra-sound sensor measures the position, quality and size of the emulsion band. The first principles based model takes into account the geometry of the desalter system, physical properties of the crude oil and water, as well as the operating conditions. Thus, the method provides users with sensing of an emulsion layer through ultrasound measurements and also gives recommendations on appropriate corrective actions to be initiated during upsets.

Abstract: The present invention provides a control system for the conversion of carbonaceous feedstock into a gas. In particular, the control system is designed to be configurable for use in controlling one or more processes implemented in, and/or by, a gasification system for the conversion of such feedstock into a gas, which may be used for one or more downstream applications. Gasification processes controllable by different embodiments of the disclosed control system may include in various combinations, a converter, a residue conditioner, a recuperator and/or heat exchanger system, one or more gas conditioners, a gas homogenization system and one or more downstream applications. The control system operatively controls various local, regional and/or global processes related to the overall gasification process, and thereby adjusts various control parameters thereof adapted to affect these processes for a selected result.

Abstract: A method of operating a furnace having process tubes and multiple burners where it is desired to conform the temperatures of the process tubes to selected target temperature criterion. The present method provides a systematic and quantitative approach to determine how to adjust burner flow rates to result in desired tube wall temperatures, for example to minimize the temperature deviation between tube wall temperatures at a predetermined elevation in the furnace.

Abstract: The subject mater herein relates to coal mills and, more particularly, inferential pulverized fuel flow sensing and manipulation within a coal mill. Various embodiments provide systems, methods, and software to manipulate a primary air flow rate and a coal feed rate into a coal mill to produce a target pulverized fuel flow. Some embodiments include sensing a differential pressure between two or more locations within a coal mill to estimate a recirculated load of coal at one or more stages within the coal mill.

Abstract: A method includes receiving a measurement associated with a cloud point of a biofuel being produced in a refining system. The method also includes determining how to adjust the refining system based on a desired cloud point of the biofuel and the measurement associated with the cloud point. The method further includes outputting a control signal to adjust the refining system based on the determination. Determining how to adjust the refining system could include determining how to adjust an inlet temperature of a reactor in the refining system. The reactor could represent an isomerization reactor, and a heater could heat material entering the isomerization reactor. Determining how to adjust the inlet temperature of the reactor could include determining how to adjust operation of the heater. A model predictive control (MPC) technique could be used to determine how to adjust the inlet temperature of the isomerization reactor.

Abstract: A method for removing calcium, iron, other metals, and amines from crude oil in a refinery desalting process includes the steps of adding a wash water to the crude oil; adding the wash water to the crude oil to create an emulsion; adding to the wash water, the crude oil or the emulsion an acid additive consisting of at least one of the following: oxalic acid, citric acid, water-soluble hydroxyacid selected from the group consisting of glycolic acid, gluconic acid, C.sub.2-C.sub.

Abstract: The present invention provides novel techniques for optimizing and controlling production plants using parametric multifaceted models. In particular, the parametric multifaceted models may be configured to convert a first set of parameters (e.g., control parameters) relating to a production plant into a second set of parameters (e.g., optimization parameters) relating to the production plant. In general, the first set of parameters will be different than the second set of parameters. For example, the first set of parameters may be indicative of low-level, real-time control parameters and the second set of parameters may be indicative of high-level, economic parameters. Utilizing appropriate parameterization may allow the parametric multifaceted models to deliver an appropriate level of detail of the production plant within a reasonable amount of time.

Abstract: A method is provided for controlling a multi-stage process. The process comprises multiple first stage processes for producing an intermediate product from a feed, and multiple further stage processes for producing an end-product from the intermediate products. The first stage processes comprise multiple intermediate processes and the further stage processes comprise multiple end processes for producing the end product. An intermediate controller controls the first stage processes in response to one or more product properties of the end product EP and a further controller FC controls the further stage processes in response to the product properties of the intermediate product. The multi-stage process further comprises the step of assigning process values to each of the end processes and the intermediate processes. The intermediate controller IC controls operation of the intermediate processes to optimize the overall process value for producing the end product.

Abstract: A method and apparatus for use in generating hydrogen are disclosed. The apparatus includes a fuel processor capable of producing a reformate from a fuel; a hydrogen purifier capable of generating a purified hydrogen gas stream from the reformate; a compressor capable of providing the reformate from the fuel processor to the pressure swing adsorption unit at a desired pressure; and a control system capable of integrating and controlling the operation of the fuel processor, the pressure swing adsorption unit, and the compressor. In another aspect, the invention includes a method for controlling the operation of a purified hydrogen generator, the method comprising: controlling the operation of a hydrogen generator; controlling the operation of a hydrogen purifier; and synchronizing the controlled operation of the hydrogen generator with the controlled operation of the hydrogen purifier.

Abstract: This invention describes a new process for monitoring and regulation of an industrial unit that comprises a closed-loop identification phase for the parameters of a model of said industrial unit, implemented in a multi-variable, predictive linear monitor, whereby said identification phase is implemented in a closed loop, which makes it possible to minimize the substandard production of said unit.

Abstract: An apparatus and method for producing a hydrogen-enriched reformate. The apparatus includes a fuel processor for converting a fuel to a reformate having fluctuations in pressure and or flow rate, means for reducing the fluctuations, a compression unit for compressing the reformate and one or more of a purification unit and a storage unit downstream of a compression unit. Means for reducing the fluctuations in the reformate can include one or more of a buffer and a conduit for providing a controlled flow of a supplemental fluid to an inlet of the compression unit. The supplemental fluid can include the compressed reformate, a hydrogen-enriched reformate, and mixtures thereof. The apparatus can include means for regulating power to the compression unit that can incrementally increase power to the compression unit particularly during start up. The purification unit can include one or more of a hydrogen selective membrane and a pressure swing adsorption unit. Methods for producing hydrogen are also disclosed.

Abstract: An apparatus and a method for use in controlling the apparatus are disclosed. The apparatus includes a purified hydrogen generator; at least one of a compression unit, a storage unit, and a dispensing unit; and a system controller. The system controller is capable of monitoring the operation of the hydrogen generator and the compression unit, storage unit, or dispensing unit at a system level and shutting down at least one of hydrogen generator and the compression unit, storage unit, or dispensing unit upon the detection of a dangerous condition.

Abstract: The present invention is directed to innovative and unique mathematical models that capture key constraints, process kinetics and control structures such that a wide envelope of hydrogen gas and associated light gas supply, distribution and use can be modeled. The present invention is also directed to a real time optimization (RTO) computer application for effective optimization of hydrogen and associated light gas supply and distribution and, thereby, consumption, in a refinery that employs said models and solves an objective function, as well as to a method and refinery using the same. The objective function can be an economic objective function such as the minimization of cost for hydrogen supply and distribution or the maximization of profit based on a valuation of products made by hydrogen consumers in the hydrogen system minus the corresponding cost of the hydrogen supply and distribution.

Abstract: A method and apparatus for use in regenerating a reactor shift bed catalyst are disclosed. The method comprises monitoring the saturation level of a reactor shift bed catalyst in a reformer; automatically detecting that the reactor shift bed catalyst has entered a saturated state; and automatically regenerating the reactor shift bed catalyst in response to automatically detecting the saturated state. The apparatus may be, in various aspects, a program storage method encoded with instructions that, when executed by a computing device, performs such a method; a computing apparatus programmed to perform such a method, or a control system performing such a method.

Abstract: A system for optimizing a power plant includes a chemical loop having an input for receiving an input parameter (270) and an output for outputting an output parameter (280), a control system operably connected to the chemical loop and having a multiple controller part (230) comprising a model-free controller. The control system receives the output parameter (280), optimizes the input parameter (270) based on the received output parameter (280), and outputs an optimized input parameter (270) to the input of the chemical loop to control a process of the chemical loop in an optimized manner.

Abstract: A control technique for use in a fuel processor is disclosed. In one aspect, a control system includes a subsystem manager controller the operation of a respective physical subsystem for each of a plurality of physical subsystems in the fuel processor. The subsystem managers take their direction from a master control manager. In a second aspect, the subsystem managers collectively form a layer operating in conjunction with a second layer capable of interfacing the subsystem managers to their respective physical subsystems, a third layer capable of interfacing the subsystem managers with the second layer. In a third aspect, master control manager manages the operation of each physical subsystem through a respective subsystem manager, directs state transitions of the subsystem managers, and routs interaction between the subsystem managers from the master control manager.

Abstract: A method for quantitative determination of hydrocarbon species in a hydrocarbon sample is disclosed. The method uses Townsend Discharge Nitric Oxide Chemical Ionization Gas Chromatography/Mass Spectrometry.

Abstract: At least one of the multiple process parameters (MPPs) is a controllable process parameter (CTPP) and one is a targeted process parameter (TPP). The process also has a defined target limit (DTV) representing a first limit on an actual average value (AAV) of the TPP. A first logical controller predicts future average values (FAVs) of the TPP based on the AAVs of the TPP over a first prior time period and the DTV. A second logical controller establishes a further target limit (FTV) representing a second limit on the AAV of the TPP based on one or more of the predicted FAVs, and also determines a target set point for each CTPP based on the AAVs of the TPP over a prior time period and the FTV. The second logical controller directs control of each CTPP in accordance with the determined target set point.

Abstract: A connector software that connects on-line interfaces used in automation systems with transaction processing for distribution of data over a global communication network comprising a configurable connector software running on memory in a computer, a configurable connector software server interface adapted to receive at least one client request from at least one client application for data and sending the data in a server response to those requests, a configurable connector software client interface adapted to issue at least one client request to at least one server application for data and for receiving the data in a server response to those requests, configurable connector software publishing interface adapted to send data to a message queue, configurable connector software subscriber interface adapted to receive data from the message queue, and wherein the message queue for the configurable connector software subscriber interface is a different message queue than the configurable connector software publishi

Abstract: Method and apparatus for performing diagnostics in a pneumatic control loop for a control valve. Pressure and displacement sensors normally provided with a positioner are used to detect operating parameters of the control loop. A processor is programmed to receive feedback from the sensors and generate fault signals according to a logic sub-routine. The logic sub-routine may include calculating mass flow of control fluid through spool valve outlet ports and comparing other operating parameters of the control fluid to detect leaks and blockages in the control loop. Once a fault is detected, the location of the root cause of the fault may be identified by characterizing operating parameters of the control loop at the time of the fault.

Abstract: A method and apparatus for determining which condition in a fuel processor has initiated a shutdown of the fuel processor are disclosed. In general, the apparatus generates a plurality of shutdown initiator signals, each corresponding to one of a plurality of shutdown conditions and indicating whether such condition is present. The shutdown initiator signals are read within a predetermined window. At least one of the read shutdown initiator signals indicates that a corresponding first shutdown condition has occurred and identifies the corresponding first shutdown condition as the firstout.

Abstract: Method and apparatus for performing diagnostics in a pneumatic control loop for a control valve. Pressure and displacement sensors normally provided with a positioner are used to detect operating parameters of the control loop. A processor is programmed to receive feedback from the sensors and generate fault signals according to a logic sub-routine. The logic sub-routine may include calculating mass flow of control fluid through spool valve outlet ports and comparing other operating parameters of the control fluid to detect leaks and blockages in the control loop. Once a fault is detected, the location of the root cause of the fault may be identified by characterizing operating parameters of the control loop at the time of the fault.

Abstract: A method of operation of a steam stripped fractionation column by using a computer to process the relevant operating parameters of the column to determine the undesirable approach to a possible flooding condition.

Abstract: The present invention relates to a voice output apparatus capable of, in response to a particular stimulus, stopping outputting a voice and outputting a reaction. The voice output apparatus is capable of outputting a voice in a natural manner. A rule-based synthesizer 24 produces a synthesized voice and outputs it. For example, when a synthesized voice “Where is an exit” was produced and outputting of the synthesized voice data has proceeded until “Where is an e” has been output, if a user taps a robot, then a reaction generator 30 determines, by referring to a reaction database 31, that a reaction voice “Ouch!” should be output in response to being tapped. The reaction generator 30 then controls an output controller 27 so as to stop outputting the synthesized voice “Where is an exit?” and output the reaction voice “Ouch!”.

Abstract: A process for the prediction and the optimization of the output of a plant producing products form incoming materials. The incoming materials are classified according to various physical characteristics and costs. The desired or ordered products are also classified according to price and physical requirements. The incoming materials information and the product information is entered into a database which is accessible by a computing device. The computing device then calculates the optimal production process by calculating a plurality of production cycles and selecting the cycle with the optimum profitability. The computing device is programmed with non-linear equations derived from a regressive analysis of data collected from samples of incoming materials and products.

Abstract: An injection mold apparatus has multiple injection zones, each zone having at least one heater and at least one temperature sensor generating a temperature indicating signal. A power source provides power to the heaters. A controller controls the temperature of at least some of the zones. For efficiency, the controller has two separate processors, a data-receiving processor for receiving temperature indicating signal from each sensor as well as power signals, and a control processor for receiving data from the data-receiving processor and for controlling the amount of power provided to the heaters. Preferably, the control is in a housing, with the housing mounted directly on the mold. Modified PID calculations are utilized. Power calculations for the amount of power to the heaters utilizes a modulo based algorithm.

Abstract: A system for monitoring fuel consumption and optimizing refueling of a vehicle. The system includes a fuel level sensor designed to be mounted on a fuel tank. The fuel sensor has a transducer, such as an ultrasonic transducer, for generating a distance signal that represents the distance between the sensor and the surface of the fuel in the fuel tank. A processor coupled to the transducer is programmed to convert the distance signal to a percentage of capacity signal, calculate the volume of fuel within the fuel tank, and create a message that includes information regarding the volume of fuel in the fuel tank. The processor of the fuel level sensor is coupled to a network that may include a dispatch terminal, a fuel optimization server, and a fuel-price-by-location service. The network calculates an optimal location for refilling the fuel tank and a route to travel to the location.

Abstract: The invention relates to a device for balancing the weight carried by a robot arm of a robot. Said device comprises a fluid spring, rotably a pneumatic spring, and a control device for controlling the movements of the robot. The device is characterized by a pressure sensor which measures the pressure of the fluid of the fluid spring. Said device and the method provided for by the invention permit the exact adjustment and balancing of the movements of the robot arm.

Abstract: A model to predict the quality of a lubricant base stock for use in a plurality of products having a plurality of viscosities. The compositional model is based on a quantitative analysis of key compositional parameters and performance criteria for the plurality of products representing the plurality of viscosities. The compositional model provides a method for making a lubricant base stock to be used in manufacturing a lubricant for a particular application from a refinery stream wherein the lubricant base stock and the refinery stream are characterizable according to a plurality of compositional components common to the base stock and to the refinery stream. This method begins with determining the acceptable region and adjusting for viscosity variations.

Abstract: A model to predict the quality of a lubricant base stock for use in a plurality of products having a plurality of viscosities. The compositional model is based on a quantitative analysis of key compositional parameters and performance criteria for the plurality of products representing the plurality of viscosities. The compositional model predicts whether the composition of a new lubricant base stock is similar or dissimilar to known lubricant base stock compositions that have previously passed or failed performance tests. New base stock compositions, then, are evaluated in light of base stocks that have demonstrated acceptable performance in a plurality of products. The compositional model also predicts whether a combination of refinery streams can be blended for use in manufacturing a lubricant base stock.

Abstract: Object services like methods or properties are provided to or inherited by objects dynamically during run-time. In one method of providing dynamic inheritance, hierarchical relationships are defined between multiple objects such that each object references or is referenced by another object. A call is made for a particular service (e.g., a method or property) at a selected object. The service is provided directly from the object whenever the service is available therefrom. Whenever the selected service is unavailable at the selected object, the call is passed to a hierarchically superior object. Another aspect of dynamic inheritance is that an object, such as the root object, may include one or more methods for adding or otherwise changing the methods or properties available from that object.