conventional induction cooking involves use of a vessel made of ferrous or similar material , where the vessel receives electromagnetic energy from an em radiation source . described herein are a variety of other applications that utilize induction technology to provide targeted heat to a given location . as discussed herein , the use of em radiation enables the provision of heat at a distance . ferrofluid is a name sometimes used to refer to a colloidal liquid that includes ferrous particles which have a diameter of approximately 10 nanometers ( nm ) or less . in alternative embodiments , the ferrous particles may have a smaller or larger diameter , depending on the application . the ferrous particles can be magnetite , iron , cobalt , nickel , and / or oxides thereof . the ferrous particles may be treated with a surfactant that prevents the particles from bunching up due to magnetic forces . the ferrous particles , when in the presence of an electromagnetic field of the kind used for induction cooking , will heat up , thereby causing the ferrofluid to heat up . since this and similar colloidal liquids can flow to relatively inaccessible places , such a ferrofluid can be used in a variety of fields where non - invasive testing , monitoring , repair , and / or healing of tissue or other material is called for . such a ferrofluid can also be used to help destroy unwanted tissue or material . as one example , for various medical procedures , individuals in the past have been injected with , or asked to swallow , a radioactive fluid such that radioactive emissions can be traced throughout the individual &# 39 ; s body using radioactive detectors proximate to the individual . as a result , the patient is subject to potentially harmful radiation . ferrofluids can be used to replace the use of radioactive fluids for internal tracing / tracking in medical testing and procedures . in one implementation , a ferrofluid can be encased in a capsule that is swallowed by a patient . the capsule can be made from a plastic or other bio - compatible material . the patient is placed near or into a bank of electromagnetic ( em ) radiation sources that are configured to generate em radiation that targets the swallowed capsule . the swallowed capsule increases in temperature as a result of the em radiation , and the path of the capsule ( and ferrofluid therein ) can therefore be traced by heat detectors . the heat sensors can be mounted directly on a skin surface of the patient , or placed proximate to the patient , depending on the implementation . in an illustrative embodiment , the temperature of the capsule is controlled such that the capsule material does not melt and such that the patient is not burned or otherwise subject to discomfort . the patient can be a human or a non - human animal . ferrofluids can also be injected into a plant such that progress of the ferrofluid throughout the plant tissue can be monitored . ferrofluids can further be used in industrial processes to detect and / or track the path of a fluid in a closed system . such tracking will enable the ready detection of obstructions or anomalies in tissue or other closed systems . ferrofluid tracking will also enable determination of the rate of movement within a closed system , and excessive heat at a given point in the system may signal an obstruction or other problem needing attention . in an alternative embodiment , a bio - compatible ferrofluid may be directly swallowed by or injected into an individual without being encapsulated . in another alternative embodiment , a solid ferrous element may be coated by plastic , etc . and swallowed by an individual for use in tracking / monitoring of the individual . coating the ferrous element can help to ensure that there is no chemical reaction with or corrosive effect on the body / system into which the ferrous element is introduced . the use of ferrous material and induction heating allows heating , repair , control , etc . to take place without limitation as to the target area . where the material to be heated is directly accessible , a ferrous element can be placed directly on or near the material . upon receipt of em radiation , the ferrous element will heat up , causing the material on which it is positioned to also heat up . the use of ferrofluids extends this feature by allowing the same technology to be used to provide heat in closed and otherwise inaccessible systems . as an example , a tumor may be located in a living being . a ferrofluid can be injected into the tumor using a standard syringe . upon application of em radiation to the injected ferrofluid , the ferrofluid can heat up thereby causing the tumor to heat up . the em radiation can be controlled such that tissue of the tumor is heated to a point where the tissue dies , destroying the tumor in the process . excess heat will pass through surrounding tissue and quickly dissipate without significant discomfort to the person / animal whose tumor is being treated . in another embodiment , an area to be subjected to heat may be entirely inaccessible . in such instances , a ferrofluid moving through the body or other system can be used in conjunction with highly targeted em radiation to monitor or treat the area . specifically , the ferrofluid can be inserted into a closed system that includes the inaccessible area , such a human body , an animal , a plant , a mechanical system , etc . the inserted ferrofluid will traverse the closed system through the blood stream , digestive system , or other passageways in the system . the targeted em radiation can be directed to the inacessable area of the closed system . as the ferrofluid passes through the inaccessible area , it receives the targeted em radiation and heats up , causing the inaccessible area to receive heat . such a procedure can be used to treat the inaccessible area with heat , to determine how long it takes for the ferrofluid to travel to the inaccessible area , enhance the effectiveness of medication , etc . induction heating can also be used in conjunction with functionalized magnetic nanoparticles which have been used for drug delivery , cell separation , and / or cell stimulation . having the ability to add heat at a distance significantly expands the efficacy and use of such nanoparticles in medical and other applications . for example , certain chemical reactions take place only in the presence of heat , heat can be used to shed a protective covering of a reactant , and heat can modify a medium for cell growth . the embodiments described herein can be used anywhere that there is a need or benefit for heat to be present at a distance or through a non - ferrous barrier . as another example , such embodiments can be used in the printing process , which traditionally requires the physical deposition of ink onto paper ( or other substrate ) or the fusion of carbon onto paper through a laser . in accordance with an illustrative embodiment , a thermally sensitive paper ( or thermal paper ) can be used in conjunction with a ferrous metal substrate . the thermal paper is treated with a chemical that changes color when exposed to heat . as a non - limiting example , the chemical used to treat the paper can be a solid - state mixture of a dye and a suitable matrix , such as a combination of a fluoran leuco dye . upon heating of the matrix to a temperature above its melting point , the dye reacts with the acid , changes color , and then remains as the changed color upon cooling of the matrix back into a solid state . such a thermal paper can be used in conjunction with a ferrous substrate to print from a distance using induction heating technology . specifically , the thermal paper can be placed in contact with or near the ferrous substrate . targeted em radiation can be applied from a distance to various portions of the ferrous substrate , which causes the ferrous substrate and hence the thermal paper to heat up . the heated portions of the thermal paper change color and this process can be used to impose letters , numbers , images , etc . onto the thermal paper . in one implementation , the ferrous substrate can be divided into a plurality of small , individually targetable areas ( spatially similar to pixels in a liquid crystal display ), and a computing device can be used to control targeting of the em radiation to form a pattern , image , text , etc . on the substrate such that the pattern , image , text , etc . is imposed onto the thermal paper . the computing device can include instructions stored on a memory and executable by a processor . various areas of the thermal paper can be heated simultaneously to form the image onto the paper . alternatively , the targeted em radiation can be used to iteratively form the image one area at a time . in another illustrative embodiment , the thermal paper can be configured such that heating at different temperatures will result in the generation of different colors . in such an implementation , color images , patterns , text , etc . can be imposed on the thermal paper . such a multicolor thermal paper can be generated using multi - layer coatings in which each coating layer results in a different color activated at a different temperature . the different temperatures can be achieved in different areas by selectively controlling the magnitude , duration , and location of the em radiation onto the ferrous substrate proximate to the multicolor thermal paper . as a result of these embodiments , it will be possible to print at a distance without the need for physical deposition of an ink or fusion of carbon . in another embodiment , induction heating can be used to power a sign in an area where there is no source of electrical power . the sign can , for example include a plurality of ferrous elements in a grid - like or other pattern and the ferrous elements can be separated from one another by non - ferrous insulating dividers . targeted em radiation can be used to heat up specific ferrous elements of the sign in the form of a pattern , image , text , etc . the heat generated by the ferrous elements can cause the ferrous elements to become visible in a dark environment such that the pattern , image , text , etc . on the sign appears to be lit up . alternatively , the heated pattern may cause a visible reaction of another material incorporated into the sign , again causing the heated areas to become visible in a dark environment . fig1 depicts such a sign 100 in accordance with an illustrative embodiment . the sign 100 includes a plurality of squares of ferrous elements 105 which are separated from one another by insulating barriers 110 . the ferrous elements 105 of the sign 100 are arranged in a grid - like pattern and can be controlled by targeting desired portions of the grid . as depicted in fig1 , the ferrous element at location ( 3 , 2 ) is being targeted with em radiation and is therefore visible on the sign . a large sign can be composed of hundreds or thousands of such targetable ferrous elements in a grid - like or other pattern . fig2 is a flow diagram illustrating a process for remotely heating objects in accordance with an illustrative embodiment . in an operation 200 , one or more ferrous elements are positioned in a desired location . the one or more ferrous elements can refer to ferrous particles in a ferrofluid that is to be swallowed by or injected into a patient , ferrous elements arranged in a sign , a ferrous plate used for remote printing , etc . in an operation 205 , em radiation is applied to at least a portion of the one or more ferrous elements . the em radiation can be applied by any type of em radiation source known to those of skill in the art . in an illustrative embodiment , the em radiation is applied in a targeted manner such that only a portion of the one or more ferrous elements are heated . in such an embodiment , the em radiation can be applied in a particular pattern such that a shape , image , text , etc . is formed as a result of the heated pattern . a computing device can be used to determine the pattern and to apply the em radiation in the targeted pattern . in an alternative embodiment , the one or more ferrous elements may be completely bathed in em radiation such that all of the ferrous elements are caused to heat up . in an operation 210 , heat that is generated by the one or more ferrous elements is detected . for example , in the context of tracing materials in a closed system , detectors can be used to determine the amount of time it takes for the ferrous elements to travel a certain distance , whether there are impassable blockages in certain areas , etc . in alternative embodiments such as activation of thermal paper , the operation 210 may not be performed as there is no need to detect the heat in such implementations . in an illustrative embodiment , control of the heating elements described herein can be implemented at least in part as computer - readable instructions stored on a computer - readable medium , such as a computer memory or storage device . upon execution of the computer - readable instructions by a processor , the computer - readable instructions can cause the computing device to perform the operations to heat materials in a desired fashion . the foregoing description of illustrative embodiments has been presented for purposes of illustration and of description . it is not intended to be exhaustive or limiting with respect to the precise form disclosed , and modifications and variations are possible in light of the above teachings or may be acquired from practice of the disclosed embodiments .
a system and method for inductive heating applications includes positioning one or more inductive heating elements in a location , delivering electromagnetic radiation , by a radiation source , to heat at least a portion of the one or more inductive heating elements , and detecting , by a detector , the heat generated by the one or more inductive heating elements . the system and method also include controlling , by a processing unit , a condition based on the detected heat .