A field-based similarity search system and method includes a database for storing at least one candidate molecule, an input device for inputting a query molecule, and a processor for identifying a candidate molecule which is similar to the query molecule based on a similarity of fragment pair features. In the internal combustion engine, cylinders are provided with the cylinders spaced apart from each other in a V-shape, and exhaust gas obtained from an exhaust port of the rear cylinder is supplied to intake ports of the respective cylinders via a single EGR control valve through exhaust-gas supply channels having a branching chamber. The second region has a semiconductor superlattice structure formed by laminating a barrier layer and a well layer alternately, the intermediate region has a semiconductor superlattice structure formed by laminating a barrier layer and a well layer alternately. The technician then goes through a predetermined list of work items or actions while verbally describing to the call center personnel each item and while taking photos of key items. The latch and locking mechanisms do not operate through door 60 such that the front of door 60 may be featureless.