A bi-directional DC-to-DC power converter is provided. The apparatus includes: an adjusting unit configured to control rotation or movements of the heavy load so that collision or interference of the heavy load with a facility around a road or a peripheral environmental condition is prevented in a process of transporting the heavy load after the heavy load is fixedly mounted to the adjusting unit. The media sheet has two lateral sides, a leading edge, and a trailing edge. A spring is engageable with the lever for urging the lever to move the control structure toward the first position. Clamp member has a bore that adjustably and securely retains a support rod, which has a swivel foot at one end. The method also includes enabling a software entity to request a service represented in the repository, the service representing a first operation on one or more data elements in a first collection from the collections, and executing the first operation on the one or more data elements in the first collection.