Abstract: An energy-saving control system of an excavator, including an engine, a main pump (1), a pilot handle, a pilot pressure pump (2), pilot control valves (4), a controller, a main control multi-way valve (3) and an execution mechanism. The main pump controls the execution mechanism via the main control multi-way valve (3). The oil paths connecting the main pump to the execution mechanism are provided with high pressure sensors (6) for transmitting signals to the controller. The main pump adjusts the flow rate thereof according to the pressure of a negative feedback oil path. The oil paths interconnecting the output end of the pilot handle with the main pump is provided with electromagnetic proportional reducing valves (7) and shuttle valves (8). A pilot oil path sequentially passes through the electromagnetic proportional reducing valves (7) and the shuttle valves (8) to control the flow rate of the main pump.

Abstract: Described is a technology by which a content server downloads an active content measuring tool object to a client request for a page. When loaded, the measuring tool object makes network measurements, including by direct socket access, and return measurement results. As part of its operations, the measuring tool object may request measurement assignments from a central controller, and/or return those results to the central controller. Measurement assignments may be directed towards determining a round trip time/latency, measuring throughput, packet loss rate, detecting in-fight modification of content and/or detecting the presence of a middle box, including the presence of a caching proxy server middle box. The measurement results may be used to evaluate hypothetical deployment of a number of servers and/or geographic locations for those servers.