MDS 621.3209

Wording: Applied science & technology Engineering Applied physics Electronics & Computers Lighting Not set Not set

Dewmoji: 💡🔩🏭⚡💡??

0 Computer science, information & general works 252,013 ℹ️	1 Philosophy & psychology 270,129 🧠	2 Religion 681,242 🙏	3 Society, government, & culture 1,328,382 👫	4 Language 209,883 💬	5 Natural sciences & mathematics 431,918 🔬	6 Applied science & technology 940,635 💡	7 Arts & recreation 1,031,850 🎨	8 Literature & rhetoric 1,436,736 📚	9 History & geography 837,760 🗺️
60 Technology 9,943 💡	61 Medicine & health 306,082 💉	62 Engineering 157,979 🔩	63 Agriculture 88,093 🌱	64 Home economics & family management 172,237 🏠	65 Management & public relations 145,064 👔	66 Chemical engineering 19,470 🚀	67 Manufacturing 8,724 📦	68 Manufacture for specific uses 20,805 🔨	69 Buildings 12,238 👷
620 Mechanical & Civil Engineering 21,480 🔩	621 Applied physics 47,082 🏭	622 Mining and related operations 3,895 🕳	623 Military Vehicles: Land, Air, & Sea 15,890 ⚓	624 Bridges & Tunnels 8,105 🌉	625 Railroads, Subways, Roads 6,655 🛤	626 [Formerly: Canal Engineering] 83	627 Dams, Lighthouses, Drilling Platforms 1,873 🌊	628 Water Treatment & Waste Disposal 7,319 🚽	629 Transportation Vehicles 45,597 🌿
621.0 1,207	621.1 Steam engineering 687	621.2 Hydraulic machinery 291	621.3 Electronics & Computers 33,501 ⚡	621.4 Engines, Power Plants, Tools 4,105 ⚙️	621.5 Pneumatic machinery and Compressed air and Refrigeration and refrigerating machinery 454	621.6 Fans (Machinery) and Pumping machinery 161	621.7 Production engineering and Factories and Machine-shop practice 182	621.8 Machine Engineering 2,644	621.9 Machine-tools 1,518
621.30 Electric power plant 436	621.31 Generation, modification, storage, transmission of electric power 5,025	621.32 Lighting 393 💡	621.33 Electric Railways 50 🚅	621.34 Magnets and Electromagnets 121 🧲	621.35 Batteries and Superconductivity 40 🔋	621.36 Optical engineering 2,905	621.37 Electrical Measurement Instruments 156	621.38 Electronics, communications engineering 20,091	621.39 Computer engineering 2,322 💻
621.320 17	621.321 Principles of lighting 6	621.322 Lighting in specific situations 43	621.323 12	621.324 1	621.325	621.326 3	621.327 14	621.328 13	621.329 6
621.3200	621.3201	621.3202 5	621.3203	621.3204	621.3205	621.3206 2	621.3207	621.3208 1	621.3209 9
621.32090	621.32091	621.32092 2	621.32093 1	621.32094	621.32095	621.32096	621.32097	621.32098	621.32099