SIC CODES

List of Economic Activities by word: process

If you are searching for an Economic Activity corresponding to "process" here you have a list of SIC items for this word

Economic Activities for process

There are 26 Economic Activities in all levels that containg the word "PROCESS" in their name or detailed description. Have you that what you are searching for?

  • Class 1520
    Manufacture of footwear
    This class includes:
    ~ manufacture of footwear for all purposes, of any material, by any PROCESS, including moulding (see below for exceptions)
    ~ manufacture of leather parts of footwear: manufacture of uppers and parts of uppers, outer and inner soles, heels etc.
    ~ manufacture of gaiters, leggings and similar articles

  • Class 2310
    Manufacture of glass and glass products
    This class includes the manufacture of glass in all forms, made by any PROCESS and the manufacture of articles of glass.

    This class includes:
    ~ manufacture of flat glass, including wired, coloured or tinted flat glass
    ~ manufacture of toughened or laminated flat glass
    ~ manufacture of glass in rods or tubes
    ~ manufacture of glass paving blocks
    ~ manufacture of glass mirrors
    ~ manufacture of multiple-walled insulating units of glass
    ~ manufacture of bottles and other containers of glass or crystal
    ~ manufacture of drinking glasses and other domestic glass or crystal articles
    ~ manufacture of glass fibres, including glass wool and non-woven products thereof
    ~ manufacture of laboratory, hygienic or pharmaceutical glassware
    ~ manufacture of clock or watch glasses, optical glass and optical elements not optically worked
    ~ manufacture of glassware used in imitation jewellery
    ~ manufacture of glass insulators and glass insulating fittings
    ~ manufacture of glass envelopes for lamps
    ~ manufacture of glass figurines

  • Class 2220
    Manufacture of plastics products
    This class includes the processing of new or spent (i.e. recycled) plastics resins into intermediate or final products, using such processes as compression molding, extrusion molding, injection molding, blow molding and casting. For most of these, the production PROCESS is such that a wide variety of products can be made.

    This class includes:
    ~ manufacture of semi-manufactures of plastic products:
    ~ plastic plates, sheets, blocks, film, foil, strip etc. (whether self-adhesive or not)
    ~ manufacture of finished plastic products:
    ~ plastic tubes, pipes and hoses; hose and pipe fittings
    ~ manufacture of plastic articles for the packing of goods:
    ~ plastic bags, sacks, containers, boxes, cases, carboys, bottles etc.
    ~ manufacture of builders' plastics ware:
    ~ plastic doors, windows, frames, shutters, blinds, skirting boards
    ~ tanks, reservoirs
    ~ plastic floor, wall or ceiling coverings in rolls or in the form of tiles etc.
    ~ plastic sanitary ware, such as:
    ~~ plastic baths, shower baths, washbasins, lavatory pans, flushing cisterns etc.
    ~ manufacture of plastic tableware, kitchenware and toilet articles
    ~ cellophane film or sheet
    ~ manufacture of resilient floor coverings, such as vinyl, linoleum etc.
    ~ manufacture of artificial stone (e.g. cultured marble)
    ~ manufacture of plastic signs (non-electrical)
    ~ manufacture of diverse plastic products:
    ~ plastic headgear, insulating fittings, parts of lighting fittings, office or school supplies, articles of apparel (if only sealed together, not sewn), fittings for furniture, statuettes, transmission and conveyer belts, self-adhesive tapes of plastic, plastic wall paper, plastic shoe lasts, plastic cigar and cigarette holders, combs, plastics hair curlers, plastics novelties, etc.

  • Class 2651
    Manufacture of measuring, testing, navigating and control equipment
    This class includes the manufacture of search, detection, navigation, guidance, aeronautical and nautical systems and instruments; automatic controls and regulators for applications, such as heating, air-conditioning, refrigeration and appliances; instruments and devices for measuring, displaying, indicating, recording, transmitting and controlling industrial PROCESS variables, such as temperature, humidity, pressure, vacuum, combustion, flow, level, viscosity, density, acidity, concentration and rotation; totalizing (i.e. registering) fluid meters and counting devices; instruments for measuring and testing the characteristics of electricity and electrical signals; instruments and instrumentation systems for laboratory analysis of the chemical or physical composition or concentration of samples of solid, fluid, gaseous or composite material and other measuring and testing instruments and parts thereof.
    The manufacture of non-electric measuring, testing, navigating and control equipment (except simple mechanical tools) is included here.

    This class includes:
    ~ manufacture of aircraft engine instruments
    ~ manufacture of automotive emissions testing equipment
    ~ manufacture of meteorological instruments
    ~ manufacture of physical properties testing and inspection equipment
    ~ manufacture of polygraph machines
    ~ manufacture of instruments for measuring and testing electricity and electrical signals (including for telecommunications)
    ~ manufacture of radiation detection and monitoring instruments
    ~ manufacture of electron and proton microscopes
    ~ manufacture of surveying instruments
    ~ manufacture of thermometers liquid-in-glass and bimetal types (except medical)
    ~ manufacture of humidistats
    ~ manufacture of hydronic limit controls
    ~ manufacture of flame and burner control
    ~ manufacture of spectrometers
    ~ manufacture of pneumatic gauges
    ~ manufacture of consumption meters (e.g. water, gas)
    ~ manufacture of flow meters and counting devices
    ~ manufacture of tally counters
    ~ manufacture of mine detectors, pulse (signal) generators; metal detectors
    ~ manufacture of search, detection, navigation, aeronautical and nautical equipment, including sonobuoys
    ~ manufacture of radar equipment
    ~ manufacture of GPS devices
    ~ manufacture of environmental controls and automatic controls for appliances
    ~ manufacture of measuring and recording equipment (e.g. flight recorders)
    ~ manufacture of motion detectors
    ~ manufacture of laboratory analytical instruments (e.g. blood analysis equipment)
    ~ manufacture of laboratory scales, balances, incubators, and miscellaneous laboratory apparatus for measuring, testing, etc.


  • Class 2652
    Manufacture of watches and clocks
    This class includes the manufacture of watches, clocks and timing mechanisms and parts thereof.

    This class includes:
    ~ manufacture of watches and clocks of all kinds, including instrument panel clocks
    ~ manufacture of watch and clock cases, including cases of precious metals
    ~ manufacture of time-recording equipment and equipment for measuring, recording and otherwise displaying intervals of time with a watch or clock movement or with synchronous motor, such as:
    ~ parking meters
    ~ time clocks
    ~ time/date stamps
    ~ PROCESS timers
    ~ manufacture of time switches and other releases with a watch or clock movement or with synchronous motor:
    ~ time locks
    ~ manufacture of components for clocks and watches:
    ~ movements of all kinds for watches and clocks
    ~ springs, jewels, dials, hands, plates, bridges and other parts

  • Class 2825
    Manufacture of machinery for food, beverage and tobacco processing
    This class includes:
    ~ manufacture of agricultural dryers
    ~ manufacture of machinery for the dairy industry:
    ~ cream separators
    ~ milk processing machinery (e.g. homogenizers)
    ~ milk converting machinery (e.g. butter chums, butter workers and moulding machines)
    ~ cheese-making machines (e.g. homogenizers, moulders, presses) etc.
    ~ manufacture of machinery for the grain milling industry:
    ~ machinery to clean, sort or grade seeds, grain or dried leguminous vegetables (winnowers, sieving belts, separators, grain brushing machines etc.)
    ~ machinery to produce flour and meal etc. (grinding mills, feeders, sifters, bran cleaners, blenders, rice hullers, pea splitters)
    ~ manufacture of presses, crushers etc. used to make wine, cider, fruit juices etc.
    ~ manufacture of machinery for the bakery industry or for making macaroni, spaghetti or similar products:
    ~ bakery ovens, dough mixers, dough-dividers, moulders, slicers, cake depositing machines etc.
    ~ manufacture of machines and equipment to PROCESS diverse foods:
    ~ machinery to make confectionery, cocoa or chocolate; to manufacture sugar; for breweries; to PROCESS meat or poultry; to prepare fruit, nuts or vegetables; to prepare fish, shellfish or other seafood
    ~ machinery for filtering and purifying
    ~ other machinery for the industrial preparation or manufacture of food or drink
    ~ manufacture of machinery for the extraction or preparation of animal or vegetable fats or oils
    ~ manufacture of machinery for the preparation of tobacco and for the making of cigarettes or cigars, or for pipe or chewing tobacco or snuff
    ~ manufacture of machinery for the preparation of food in hotels and restaurants

  • Class 3312
    Repair of machinery
    This class includes the repair and maintenance of industrial machinery and equipment like sharpening or installing commercial and industrial machinery blades and saws; the provision of welding (e.g. automotive, general) repair services; the repair of agricultural and other heavy and industrial machinery and equipment (e.g. forklifts and other materials handling equipment, machine tools, commercial refrigeration equipment, construction equipment and mining machinery), comprising machinery and equipment of division 28.

    This class includes:
    ~ repair and maintenance of non-automotive engines, e.g. ship or rail engines
    ~ repair and maintenance of pumps and related equipment
    ~ repair and maintenance of fluid power equipment
    ~ repair of valves
    ~ repair of gearing and driving elements
    ~ repair and maintenance of industrial PROCESS furnaces
    ~ repair and maintenance of materials handling equipment
    ~ repair and maintenance of commercial refrigeration equipment and air purifying equipment
    ~ repair and maintenance of commercial-type general-purpose machinery
    ~ repair of other power-driven hand-tools
    ~ repair and maintenance of metal cutting and metal forming machine tools and accessories
    ~ repair and maintenance of other machine tools
    ~ repair and maintenance of agricultural tractors
    ~ repair and maintenance of agricultural machinery and forestry and logging machinery
    ~ repair and maintenance of metallurgy machinery
    ~ repair and maintenance of mining, construction, and oil and gas field machinery
    ~ repair and maintenance of food, beverage, and tobacco processing machinery
    ~ repair and maintenance of textile apparel, and leather production machinery
    ~ repair and maintenance of papermaking machinery
    ~ repair and maintenance of other special-purpose machinery of division 28
    ~ repair and maintenance of weighing equipment
    ~ repair and maintenance of vending machines
    ~ repair and maintenance of cash registers
    ~ repair and maintenance of photocopy machines
    ~ repair of calculators, electronic or not
    ~ repair of typewriters

  • Class 3320
    Installation of industrial machinery and equipment
    This class includes the specialized installation of machinery. However, the installation of equipment that forms an integral part of buildings or similar structures, such as installation of escalators, electrical wiring, burglar alarm systems or air-conditioning systems, is classified as construction.

    This class includes:
    ~ installation of industrial machinery in industrial plant
    ~ installation of industrial PROCESS control equipment
    ~ installation of other industrial equipment, e.g.:
    ~ communications equipment
    ~ mainframe and similar computers
    ~ irradiation and electromedical equipment etc.
    ~ dismantling large-scale machinery and equipment
    ~ activities of millwrights
    ~ machine rigging
    ~ installation of bowling alley equipment

  • Class 4100
    Construction of buildings
    This class includes the construction of complete residential or non-residential buildings, on own account for sale or on a fee or contract basis. Outsourcing parts or even the whole construction PROCESS is possible. If only specialized parts of the construction PROCESS are carried out, the activity is classified in division 43.

    This class includes:
    ~ construction of all types of residential buildings:
    ~ single-family houses
    ~ multi-family buildings, including high-rise buildings
    ~ construction of all types of non-residential buildings:
    ~ buildings for industrial production, e.g. factories, workshops, assembly plants etc.
    ~ hospitals, schools, office buildings
    ~ hotels, stores, shopping malls, restaurants
    ~ airport buildings
    ~ indoor sports facilities
    ~ parking garages, including underground parking garages
    ~ warehouses
    ~ religious buildings
    ~ assembly and erection of prefabricated constructions on the site

    This class also includes:
    ~ remodeling or renovating existing residential structures

  • Class 4520
    Maintenance and repair of motor vehicles
    This class includes:
    ~ maintenance and repair of motor vehicles:
    ~ mechanical repairs
    ~ electrical repairs
    ~ electronic injection systems repair
    ~ ordinary servicing
    ~ bodywork repair
    ~ repair of motor vehicle parts
    ~ washing, polishing, etc.
    ~ spraying and painting
    ~ repair of screens and windows
    ~ repair of motor vehicle seats
    ~ tyre and tube repair, fitting or replacement
    ~ anti-rust treatment
    ~ installation of parts and accessories not as part of the manufacturing process


  • Class 4669
    Wholesale of waste and scrap and other products n.e.c.
    This class includes:
    ~ wholesale of industrial chemicals:
    ~ aniline, printing ink, essential oils, industrial gases, chemical glues, colouring matter, synthetic resin, methanol, paraffin, scents and flavourings, soda, industrial salt, acids and sulphurs, starch derivates etc.
    ~ wholesale of fertilizers and agrochemical products
    ~ wholesale of plastic materials in primary forms
    ~ wholesale of rubber
    ~ wholesale of textile fibres etc.
    ~ wholesale of paper in bulk
    ~ wholesale of precious stones
    ~ wholesale of metal and non-metal waste and scrap and materials for recycling, including collecting, sorting, separating, stripping of used goods such as cars in order to obtain reusable parts, packing and repacking, storage and delivery, but without a real transformation PROCESS. Additionally, the purchased and sold waste has a remaining value.

    This class includes:
    ~ dismantling of automobiles, computers, televisions and other equipment to obtain and re-sell usable parts

  • Group 032
    Aquaculture
    This group includes aquaculture (or aquafarming), i.e. the production PROCESS involving the culturing or farming (including harvesting) of aquatic organisms (fish, molluscs, crustaceans, plants, crocodiles, alligators and amphibians) using techniques designed to increase the production of the organisms in question beyond the natural capacity of the environment (for example regular stocking, feeding and protection from predators).
    Culturing/farming refers to the rearing up to their juvenile and/or adult phase under captive conditions of the above organisms. In addition, aquaculture also encompasses individual, corporate or state ownership of the individual organisms throughout the rearing or culture stage, up to and including harvesting.

  • Group 243
    Casting of metals
    This group includes the manufacture of semi-finished products and various castings by a casting PROCESS.
  • Division 03
    Fishing and aquaculture
    This division includes capture fishery and aquaculture, covering the use of fishery resources from marine, brackish or freshwater environments, with the goal of capturing or gathering fish, crustaceans, molluscs and other marine organisms and products (e.g. aquatic plants, pearls, sponges etc).
    Also included are activities that are normally integrated in the PROCESS of production for own account (e.g. seeding oysters for pearl production).

    This division does not include building and repairing of ships and boats (3011, 3315) and sport or recreational fishing activities (9319). Processing of fish, crustaceans or molluscs is excluded, whether at land-based plants or on factory ships (1020).

  • Division 13
    Manufacture of textiles
    This division includes preparation and spinning of textile fibres as well as textile weaving, finishing of textiles and wearing apparel, manufacture of made-up textile articles, except apparel (e.g. household linen, blankets, rugs, cordage etc.). Growing of natural fibres is covered under division 01, while manufacture of synthetic fibres is a chemical PROCESS classified in class 2030. Manufacture of wearing apparel is covered in division 14.
  • Division 22
    Manufacture of rubber and plastics products
    This division includes the manufacture of rubber and plastics products.
    This division is characterized by the raw materials used in the manufacturing PROCESS. However, this does not imply that the manufacture of all products made of these materials is classified here.

  • Division 87
    Residential care activities
    This division includes the provision of residential care combined with either nursing, supervisory or other types of care as required by the residents. Facilities are a significant part of the production PROCESS and the care provided is a mix of health and social services with the health services being largely some level of nursing services.
  • Division 19
    Manufacture of coke and refined petroleum products
    This division includes the transformation of crude petroleum and coal into usable products. The dominant PROCESS is petroleum refining, which involves the separation of crude petroleum into component products through such techniques as cracking and distillation. This division also includes the manufacture for own account of characteristic products (e.g. coke, butane, propane, petrol, kerosene, fuel oil etc.) as well as processing services (e.g. custom refining).
    This division includes the manufacture of gases such as ethane, propane and butane as products of petroleum refineries.

    Not included is the manufacture of such gases in other units (2011), manufacture of industrial gases (2011), extraction of natural gas (methane, ethane, butane or propane) (0600), and manufacture of fuel gas, other than petroleum gases (e.g. coal gas, water gas, producer gas, gasworks gas) (35420).
    The manufacture of petrochemicals from refined petroleum is classified in division 20.


  • Division 20
    Manufacture of chemicals and chemical products
    This division includes the transformation of organic and inorganic raw materials by a chemical PROCESS and the formation of products. It distinguishes the production of basic chemicals that constitute the first industry group from the production of intermediate and end products produced by further processing of basic chemicals that make up the remaining industry classes.
  • Division 24
    Manufacture of basic metals
    This division includes the activities of smelting and/or refining ferrous and non-ferrous metals from ore, pig or scrap, using electrometallurgic and other PROCESS metallurgic techniques. This division also includes the manufacture of metal alloys and super-alloys by introducing other chemical elements to pure metals. The output of smelting and refining, usually in ingot form, is used in rolling, drawing and extruding operations to make products such as plate, sheet, strip, bars, rods, wire, tubes, pipes and hollow profiles, and in molten form to make castings and other basic metal products.
  • Division 28
    Manufacture of machinery and equipment n.e.c.
    This division includes the manufacture of machinery and equipment that act independently on materials either mechanically or thermally or perform operations on materials (such as handling, spraying, weighing or packing), including their mechanical components that produce and apply force, and any specially manufactured primary parts. This includes the manufacture of fixed and mobile or hand-held devices, regardless of whether they are designed for industrial, building and civil engineering, agricultural or home use. The manufacture of special equipment for passenger or freight transport within demarcated premises also belongs within this division.
    This division distinguishes between the manufacture of special-purpose machinery, i.e. machinery for exclusive use in an ISIC industry or a small cluster of ISIC industries, and general-purpose machinery, i.e. machinery that is being used in a wide range of ISIC industries.
    This division also includes the manufacture of other special-purpose machinery, not covered elsewhere in the classification, whether or not used in a manufacturing PROCESS, such as fairground amusement equipment, automatic bowling alley equipment, etc.

    This division excludes the manufacture of metal products for general use (division 25), associated control devices, computer equipment, measurement and testing equipment, electricity distribution and control apparatus (divisions 26 and 27) and general-purpose motor vehicles (divisions 29 and 30).

  • Division 31
    Manufacture of furniture
    This division includes the manufacture of furniture and related products of any material except stone, concrete and ceramic. The processes used in the manufacture of furniture are standard methods of forming materials and assembling components, including cutting, moulding and laminating. The design of the article, for both aesthetic and functional qualities, is an important aspect of the production PROCESS.

    Some of the processes used in furniture manufacturing are similar to processes that are used in other segments of manufacturing. For example, cutting and assembly occurs in the production of wood trusses that are classified in division 16 (Manufacture of wood and wood products). However, the multiple processes distinguish wood furniture manufacturing from wood product manufacturing. Similarly, metal furniture manufacturing uses techniques that are also employed in the manufacturing of roll-formed products classified in division 25 (Manufacture of fabricated metal products). The molding PROCESS for plastics furniture is similar to the molding of other plastics products. However, the manufacture of plastics furniture tends to be a specialized activity.

  • Section C
    Manufacturing
    This section includes the physical or chemical transformation of materials, substances, or components into new products, although this cannot be used as the single universal criterion for defining manufacturing (see remark on processing of waste below). The materials, substances, or components transformed are raw materials that are products of agriculture, forestry, fishing, mining or quarrying as well as products of other manufacturing activities. Substantial alteration, renovation or reconstruction of goods is generally considered to be manufacturing.

    Units engaged in manufacturing are often described as plants, factories or mills and characteristically use power-driven machines and materials-handling equipment. However, units that transform materials or substances into new products by hand or in the worker's home and those engaged in selling to the general public of products made on the same premises from which they are sold, such as bakeries and custom tailors, are also included in this section. Manufacturing units may PROCESS materials or may contract with other units to PROCESS their materials for them. Both types of units are included in manufacturing.

    The output of a manufacturing PROCESS may be finished in the sense that it is ready for utilization or consumption, or it may be semi-finished in the sense that it is to become an input for further manufacturing. For example, the output of alumina refining is the input used in the primary production of aluminium; primary aluminium is the input to aluminium wire drawing; and aluminium wire is the input for the manufacture of fabricated wire products.

    Manufacture of specialized components and parts of, and accessories and attachments to, machinery and equipment is, as a general rule, classified in the same class as the manufacture of the machinery and equipment for which the parts and accessories are intended. Manufacture of unspecialized components and parts of machinery and equipment, e.g. engines, pistons, electric motors, electrical assemblies, valves, gears, roller bearings, is classified in the appropriate class of manufacturing, without regard to the machinery and equipment in which these items may be included. However, making specialized components and accessories by moulding or extruding plastics materials is included in class 2220.

    Assembly of the component parts of manufactured products is considered manufacturing. This includes the assembly of manufactured products from either self-produced or purchased components.

    The recovery of waste, i.e. the processing of waste into secondary raw materials is classified in class 3830 (Materials recovery). While this may involve physical or chemical transformations, this is not considered to be a part of manufacturing. The primary purpose of these activities is considered to be the treatment or processing of waste and they are therefore classified in Section E (Water supply; sewerage, waste management and remediation activities). However, the manufacture of new final products (as opposed to secondary raw materials) is classified in manufacturing, even if these processes use waste as an input. For example, the production of silver from film waste is considered to be a manufacturing PROCESS.

    Specialized maintenance and repair of industrial, commercial and similar machinery and equipment is, in general, classified in division 33 (Repair, maintenance and installation of machinery and equipment). However, the repair of computers and personal and household goods is classified in division 95 (Repair of computers and personal and household goods), while the repair of motor vehicles is classified in division 45 (Wholesale and retail trade and repair of motor vehicles and motorcycles).

    The installation of machinery and equipment, when carried out as a specialized activity, is classified in 3320.

    Remark: The boundaries of manufacturing and the other sectors of the classification system can be somewhat blurry.

  • Section E
    Water supply; sewerage, waste management and remediation activities
    This section includes activities related to the management (including collection, treatment and disposal) of various forms of waste, such as solid or non-solid industrial or household waste, as well as contaminated sites. The output of the waste or sewage treatment PROCESS can either be disposed of or become an input into other production processes. Activities of water supply are also grouped in this section, since they are often carried out in connection with, or by units also engaged in, the treatment of sewage.
  • Section F
    Construction
    This section includes general construction and specialized construction activities for buildings and civil engineering works. It includes new work, repair, additions and alterations, the erection of prefabricated buildings or structures on the site and also construction of a temporary nature.

    General construction is the construction of entire dwellings, office buildings, stores and other public and utility buildings, farm buildings etc., or the construction of civil engineering works such as motorways, streets, bridges, tunnels, railways, airfields, harbours and other water projects, irrigation systems, sewerage systems, industrial facilities, pipelines and electric lines, sports facilities etc.

    This work can be carried out on own account or on a fee or contract basis. Portions of the work and sometimes even the whole practical work can be subcontracted out. A unit that carries the overall responsibility for a construction project is classified here.

    Also included is the repair of buildings and engineering works.

    This section includes the complete construction of buildings (division 41), the complete construction of civil engineering works (division 42), as well as specialized construction activities, if carried out only as a part of the construction PROCESS (division 43).

    The renting of construction equipment with operator is classified with the specific construction activity carried out with this equipment.

    This section also includes the development of building projects for buildings or civil engineering works by bringing together financial, technical and physical means to realize the construction projects for later sale. If these activities are carried out not for later sale of the construction projects, but for their operation (e.g. renting of space in these buildings, manufacturing activities in these plants), the unit would not be classified here, but according to its operational activity, i.e. real estate, manufacturing etc.

  • Section J
    Information and communication
    This section includes the production and distribution of information and cultural products, the provision of the means to transmit or distribute these products, as well as data or communications, information technology activities and the processing of data and other information service activities.

    The main components of this section are publishing activities (division 58), including software publishing, motion picture and sound recording activities (division 59), radio and TV broadcasting and programming activities (division 60), telecommunications activities (division 61) and information technology activities (division 62) and other information service activities (division 63).

    Publishing includes the acquisition of copyrights to content (information products) and making this content available to the general public by engaging in (or arranging for) the reproduction and distribution of this content in various forms. All the feasible forms of publishing (in print, electronic or audio form, on the internet, as multimedia products such as CD-ROM reference books etc.) are included in this section.

    Activities related to production and distribution of TV programming span divisions 59, 60 and 61, reflecting different stages in this PROCESS. Individual components, such as movies, television series etc. are produced by activities in division 59, while the creation of a complete television channel programme, from components produced in division 59 or other components (such as live news programming) is included in division 60. Division 60 also includes the broadcasting of this programme by the producer. The distribution of the complete television programme by third parties, i.e. without any alteration of the content, is included in division 61. This distribution in division 61 can be done through broadcasting, satellite or cable systems.