A sun shielding device to be worn on the back of a user is provided. Dynamic determination of the time to take the measurement allows each strip to operate in the shortest appropriate time frame, thereby avoiding using an average measurement time that may be longer than necessary for some strips and too short for others. Although the invention represents software processes as stated above, it also represents processes that occur in the real-world systems being modeled by the simulation that is graphically represented by the invention. The opening 11 is disposed coaxially with the bullet passage 12 of the barrel 10 of the firearm and with a through opening 4 of the container 3 occupying such position before each shot. Forming the E-beam from a thickened distal portion and a thinned proximal strip enhances manufacturability and facilitates use in such articulating surgical instruments. 11 wireless data communications system 100 employ primitives in connection with a Schedule Quality of Service Action frame.