A lithographic projection apparatus includes a liquid confinement structure extending along at least a part of a boundary of a space between a projection system and a substrate table, the space having a cross-sectional area smaller than the area of the substrate. The \u03b2-diketonate alkoxide metal compound may include a metal M selected from Mg, Ca, Sr, Ba, Sc, Y, La, Ce, Ti, Zr, Hf, Pr, V, Nb, Ta, Nd, Cr, W, Pm, Mn, Re, Sm, Fe, Ru, Eu, Co, Rh, Ir, Gd, Ni, Tb, Cu, Dy, Ho, Al, Tl, Er, Sn, Pb, Tm, Bi, Lu, Th, Pd, Pt, Ga, In, Au, Ag, Li, Na, K, Rb, Cs, Mo, and Yb. A method of operating a valve, includes biasing a plunger to an open position, biasing a valve locking mechanism to a locked position in relation to a bore of a mineral extraction system, and biasing a plunger to a closed position. QoS is determined by looping back the stream of audio packets from the different routers. The absorption properties of the porous specimen are determined as a function of the weight data over time. The etching method comprises steps of performing a first etching process to remove a portion of the first material layer in an etching chamber and then performing an etching environment adjustment process in the etching chamber.