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Energy engineers people holding light bulbs while thinking. Innovative concept, thinking of natural energy engineering in design, Knowledge in education, inspiration and imagination in technology.
Leader concentrates team efforts on new idea. Brainstorming. Joint project. Development of innovations and technologies. Research. Cooperation. Creativity and ingenuity. Thinking process
Operational excellence concept. Productivity with excellence process. Industrial management in efficiency and efficient process. Lean cost and  productivity growth. Process of continuous improvement.
Creative image with men sitting on drawn pile books over light background. Contemporary artwork. Concept of studying, art and education. Psychology of knowledge, broadening one's horizons, frames
Studying, self-development. Hands aesthetic on bright background, artwork. Concept of community, hobbies, knowledge , symbolism, surrealism. Contemporary art collage modern design

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Handbook grunge sealImage used under license from Freestock.com<a href="https://www.freestock.com/free-photos/handbook-grunge-seal-414757258">Image used under license from Freestock.com</a>
Businessman holding book with bulb.Image used under license from Freestock.com<a href="https://www.freestock.com/free-photos/businessman-holding-book-bulb-682497208">Image used under license from Freestock.com</a>
Thoughtful young businessman standing on a pile of crumpled paper with a blueish grey backgroundImage used under license from Freestock.com<a href="https://www.freestock.com/free-photos/thoughtful-young-businessman-standing-pile-crumpled-678045703">Image used under license from Freestock.com</a>
Science rosetteImage used under license from Freestock.com<a href="https://www.freestock.com/free-photos/science-rosette-417798625">Image used under license from Freestock.com</a>
A serious businessman with laptop tablet in elegant suit sitting on a stack of books in front of cityscapeImage used under license from Freestock.com<a href="https://www.freestock.com/free-photos/serious-businessman-laptop-tablet-elegant-suit-667144102">Image used under license from Freestock.com</a>
A serious businessman in suit sitting on a pile of giant books in front of a grey wall with clouds, labirynthImage used under license from Freestock.com<a href="https://www.freestock.com/free-photos/serious-businessman-suit-sitting-pile-giant-675507703">Image used under license from Freestock.com</a>
Thoughtful young businessman standing on a pile of crumpled paper with a grungy grey backgroundImage used under license from Freestock.com<a href="https://www.freestock.com/free-photos/thoughtful-young-businessman-standing-pile-crumpled-675531727">Image used under license from Freestock.com</a>
Thoughtful young businessman standing on a pile of crumpled paper with a dark grey backgroundImage used under license from Freestock.com<a href="https://www.freestock.com/free-photos/thoughtful-young-businessman-standing-pile-crumpled-662069500">Image used under license from Freestock.com</a>
Critical gold badge or emblemImage used under license from Freestock.com<a href="https://www.freestock.com/free-photos/critical-gold-badge-emblem-413777557">Image used under license from Freestock.com</a>
Open notebook on the floor with office instruments nearby and letters on itImage used under license from Freestock.com<a href="https://www.freestock.com/free-photos/open-notebook-floor-office-instruments-nearby-654877804">Image used under license from Freestock.com</a>
E-Learning with rubber seal textureImage used under license from Freestock.com<a href="https://www.freestock.com/free-photos/elearning-rubber-seal-texture-391799029">Image used under license from Freestock.com</a>
Thoughtful young businessman standing on a pile of crumpled paper with a light grey backgroundImage used under license from Freestock.com<a href="https://www.freestock.com/free-photos/thoughtful-young-businessman-standing-pile-crumpled-667160860">Image used under license from Freestock.com</a>
Books with flying letters on vintage old backgroundImage used under license from Freestock.com<a href="https://www.freestock.com/free-photos/books-flying-letters-vintage-old-background-648417367">Image used under license from Freestock.com</a>
Young businessman sitting behind crumpled paper with grey background Image used under license from Freestock.com<a href="https://www.freestock.com/free-photos/young-businessman-sitting-crumpled-paper-grey-672709678">Image used under license from Freestock.com</a>
Graduation cap vector icon or symbolImage used under license from Freestock.com<a href="https://www.freestock.com/free-photos/graduation-cap-vector-icon-symbol-357267671">Image used under license from Freestock.com</a>
Books on top with colorful symbols on vintage old backgroundImage used under license from Freestock.com<a href="https://www.freestock.com/free-photos/books-top-colorful-symbols-vintage-old-639406660">Image used under license from Freestock.com</a>
Magical books with ray of lights and colorful clouds on vintage backgroundImage used under license from Freestock.com<a href="https://www.freestock.com/free-photos/magical-books-ray-lights-colorful-clouds-631543652">Image used under license from Freestock.com</a>
Books on top with colorful symbols on vintage old backgroundImage used under license from Freestock.com<a href="https://www.freestock.com/free-photos/books-top-colorful-symbols-vintage-old-630800552">Image used under license from Freestock.com</a>
Webinar rubber grunge texture stampImage used under license from Freestock.com<a href="https://www.freestock.com/free-photos/webinar-rubber-grunge-texture-stamp-389248966">Image used under license from Freestock.com</a>
Useless emblem draw with pencil effectImage used under license from Freestock.com<a href="https://www.freestock.com/free-photos/useless-emblem-draw-pencil-effect-429004675">Image used under license from Freestock.com</a>
Online Training written on a blackboardImage used under license from Freestock.com<a href="https://www.freestock.com/free-photos/online-training-written-blackboard-423693067">Image used under license from Freestock.com</a>
A serious businessman in elegant suit sitting on a pile of giant books in front of a grey city scape with clouds, fogImage used under license from Freestock.com<a href="https://www.freestock.com/free-photos/serious-businessman-elegant-suit-sitting-pile-367064504">Image used under license from Freestock.com</a>
Thoughtful young businessman standing on a pile of crumpled paper with a deep grey backgroundImage used under license from Freestock.com<a href="https://www.freestock.com/free-photos/thoughtful-young-businessman-standing-pile-crumpled-670200916">Image used under license from Freestock.com</a>
Online Training gold badgeImage used under license from Freestock.com<a href="https://www.freestock.com/free-photos/online-training-gold-badge-431953111">Image used under license from Freestock.com</a>
A serious businessman with tablet in hand in suit sitting on a pile of giant books in front of a greyish brown wall including drawn lines, angles, numbers, circles and curves.Image used under license from Freestock.com<a href="https://www.freestock.com/free-photos/serious-businessman-tablet-hand-suit-sitting-670163719">Image used under license from Freestock.com</a>
Thoughtful young businessman standing on a pile of crumpled paper with a blueish grey backgroundImage used under license from Freestock.com<a href="https://www.freestock.com/free-photos/thoughtful-young-businessman-standing-pile-crumpled-670200835">Image used under license from Freestock.com</a>
Young businessman sitting behind crumpled paper with drawings of gears and steam over his headImage used under license from Freestock.com<a href="https://www.freestock.com/free-photos/young-businessman-sitting-crumpled-paper-drawings-682515376">Image used under license from Freestock.com</a>
Tutorial wood emblemImage used under license from Freestock.com<a href="https://www.freestock.com/free-photos/tutorial-wood-emblem-432647992">Image used under license from Freestock.com</a>
book icon vector symbol flat eps jpg app web concept websiteImage used under license from Freestock.com<a href="https://www.freestock.com/free-photos/book-icon-vector-symbol-flat-eps-417307078">Image used under license from Freestock.com</a>
Books with flying letters on vintage old backgroundImage used under license from Freestock.com<a href="https://www.freestock.com/free-photos/books-flying-letters-vintage-old-background-621618188">Image used under license from Freestock.com</a>
E-Learning inside money style emblem or rosetteImage used under license from Freestock.com<a href="https://www.freestock.com/free-photos/elearning-money-style-emblem-rosette-420729073">Image used under license from Freestock.com</a>
Businessman wearing smartwatch with graphics and charts on it.Image used under license from Freestock.com<a href="https://www.freestock.com/free-photos/businessman-wearing-smartwatch-graphics-charts-657545050">Image used under license from Freestock.com</a>
Young businessman sitting behind crumpled paper with lightbulbs above his headImage used under license from Freestock.com<a href="https://www.freestock.com/free-photos/young-businessman-sitting-crumpled-paper-lightbulbs-682515403">Image used under license from Freestock.com</a>
Thoughtful young businessman standing on a pile of crumpled paper with a deep grey backgroundImage used under license from Freestock.com<a href="https://www.freestock.com/free-photos/thoughtful-young-businessman-standing-pile-crumpled-662069581">Image used under license from Freestock.com</a>
Graduation cap vector symbolImage used under license from Freestock.com<a href="https://www.freestock.com/free-photos/graduation-cap-vector-symbol-359849858">Image used under license from Freestock.com</a>
Thoughtful young businessman standing on a pile of crumpled paper with a grey backgroundImage used under license from Freestock.com<a href="https://www.freestock.com/free-photos/thoughtful-young-businessman-standing-pile-crumpled-667160716">Image used under license from Freestock.com</a>
Open notebook on the floor with office instruments nearby and letters on itImage used under license from Freestock.com<a href="https://www.freestock.com/free-photos/open-notebook-floor-office-instruments-nearby-645123214">Image used under license from Freestock.com</a>
Magical books with ray of lights and colorful clouds on vintage backgroundImage used under license from Freestock.com<a href="https://www.freestock.com/free-photos/magical-books-ray-lights-colorful-clouds-640525033">Image used under license from Freestock.com</a>
Young businessman sitting behind crumpled paper with lightbulbs above his headImage used under license from Freestock.com<a href="https://www.freestock.com/free-photos/young-businessman-sitting-crumpled-paper-lightbulbs-672709483">Image used under license from Freestock.com</a>
Thoughtful young businessman standing on a pile of crumpled paper with a deep grey backgroundImage used under license from Freestock.com<a href="https://www.freestock.com/free-photos/thoughtful-young-businessman-standing-pile-crumpled-654869257">Image used under license from Freestock.com</a>
A pile of books on table with school hand drawn doodle sketches and symbolsImage used under license from Freestock.com<a href="https://www.freestock.com/free-photos/pile-books-table-school-hand-drawn-613331228">Image used under license from Freestock.com</a>
Businessman holding book with doodle drawings and signs.Image used under license from Freestock.com<a href="https://www.freestock.com/free-photos/businessman-holding-book-doodle-drawings-signs-682497217">Image used under license from Freestock.com</a>
Online Coaching written inside rosetteImage used under license from Freestock.com<a href="https://www.freestock.com/free-photos/online-coaching-written-rosette-423693775">Image used under license from Freestock.com</a>
A serious businessman in suit sitting on a pile of giant books in front of a greyish brown wall with drawn lines, angles, numbers, circles and curves.Image used under license from Freestock.com<a href="https://www.freestock.com/free-photos/serious-businessman-suit-sitting-pile-giant-662041546">Image used under license from Freestock.com</a>
Graduation cap iconImage used under license from Freestock.com<a href="https://www.freestock.com/free-photos/graduation-cap-icon-378069646">Image used under license from Freestock.com</a>
A serious businessman in suit sitting on a pile of giant books in front of a grey wall with clouds, labirynthImage used under license from Freestock.com<a href="https://www.freestock.com/free-photos/serious-businessman-suit-sitting-pile-giant-686537296">Image used under license from Freestock.com</a>
Businessman wearing smartwatch with graphics and charts on it.Image used under license from Freestock.com<a href="https://www.freestock.com/free-photos/businessman-wearing-smartwatch-graphics-charts-666142606">Image used under license from Freestock.com</a>