Disclosed is a process for the production of t-butyl acetate and coproduction of methyl acetate or ethyl acetate, directly from MTBE or ETBE, by contacting a mixture of acetic acid, acetic anhydride, and MTBE, or alternatively, ETBE, with an acid catalyst. The force sensor is a modular unit with an electrode and a closure, which are mutually arranged in an essentially electrically insulated initial position. A plurality of pad electrodes are formed on the resin layer. Respective elastically deformable clips fitted to the holders below the respective anchor-bolt heads bear upwardly on the holders and downwardly on the rail foot to press the rail downwardly toward the sleeper. The halogen-free low-dielectric resin composition of the present invention uses the epoxidized polybutadiene resin, so as to not only solve the defect of the polybutadiene but also maintain the advantages on the dielectric property and flexibility, thereby improving the adhesive force thereof with the copper foil. The cover body, the emitter, and the receiver cooperatively close the open end of the receiving space.