A method and system for dynamic combinatorial auctions employing bid composition restrictions is disclosed. The sensor chip is disposed on the front opening. Such multi-phase magnetic element has an excellent ripple current property. Such arrangements not only is portable and easy to disassemble, but also is environmental protection. A dopant source layer is formed on the surface of the first trench. The hypervisor estimates a first cost of migrating the particular logical partition and a second cost of migrating the another logical partition to at least one other host system communicatively connected in a peer-to-peer network based on at least one previously recorded cost stored by the host system of migrating a previous logical partition to the at least one other host system.