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1 | (42) |
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1.1 Acoustical Measurements |
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1 | (1) |
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1.2 Instantaneous and Effective (RMS) Value |
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2 | (2) |
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4 | (1) |
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4 | (4) |
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1.4.1 Stabilization Time for Leq |
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6 | (2) |
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8 | (5) |
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13 | (4) |
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1.6.1 Stabilization Time for Exceedance Levels |
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14 | (3) |
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17 | (26) |
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1.7.1 Constant Percentage Spectrum Analyzer |
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18 | (4) |
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1.7.2 Line Spectrum Analyzer |
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22 | (1) |
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1.7.3 Line Spectrum and Time-Frequency Uncertainty |
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23 | (1) |
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1.7.4 Line Spectrum and Power Spectral Density |
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24 | (3) |
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27 | (4) |
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1.7.6 Transient Response of Band Filters |
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31 | (4) |
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1.7.7 Parseval's Identity |
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35 | (2) |
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1.7.8 Effect of Spectrum Tolerance on Parseval's Identity |
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37 | (2) |
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1.7.9 Weighted Levels Computed from One-Third Octave Bands |
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39 | (2) |
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41 | (2) |
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43 | (34) |
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43 | (1) |
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2.2 Resolution, Precision, Accuracy |
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44 | (1) |
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2.3 Measurement Method and Procedure |
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45 | (1) |
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2.3.1 Direct and Indirect Measurement Methods |
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46 | (1) |
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46 | (3) |
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49 | (6) |
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50 | (1) |
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51 | (1) |
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2.5.3 Expanded Uncertainty |
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52 | (1) |
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2.5.4 Combined Standard Uncertainty |
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53 | (2) |
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55 | (6) |
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2.6.1 Relationship Between Uncertainties in Level and Pressure |
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55 | (1) |
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2.6.2 Uncertainty in the Correction of Environmental Conditions |
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56 | (1) |
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2.6.3 Uncertainty in the Calculation of the Equivalent Level |
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56 | (2) |
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2.6.4 Uncertainty in A-Weighting Computed from Octave Spectrum |
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58 | (2) |
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2.6.5 Uncertainty in the Measurement of Sound Transmission Loss |
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60 | (1) |
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2.7 Uncertainty and Resolution |
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61 | (1) |
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2.8 Uncertainty and Systematic Error |
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62 | (10) |
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2.8.1 Additive Systematic Error |
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62 | (2) |
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2.8.2 Multiplicative Systematic Error |
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64 | (4) |
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2.8.3 Nonlinear Systematic Error |
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68 | (3) |
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2.8.4 Uncorrected Systematic Errors |
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71 | (1) |
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2.9 Chain Calculation of Uncertainty |
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72 | (5) |
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75 | (2) |
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77 | (90) |
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77 | (1) |
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77 | (1) |
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78 | (5) |
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83 | (1) |
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3.5 Signal-to-Noise Ratio |
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84 | (1) |
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85 | (1) |
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86 | (3) |
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89 | (2) |
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3.9 D/A and A/D Conversion |
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91 | (3) |
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3.9.1 Digital/Analog Conversion |
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91 | (1) |
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3.9.2 Analog/Digital Conversion |
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92 | (2) |
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3.10 Pulse Code Modulation (PCM) |
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94 | (1) |
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3.11 Differential Pulse Code Modulation (DPCM) |
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95 | (3) |
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3.12 Delta Modulation (DM) |
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98 | (2) |
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3.13 Sigma-Delta Modulation (SDM) |
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100 | (4) |
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3.14 Digital Recording Devices |
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104 | (2) |
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106 | (17) |
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108 | (7) |
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115 | (8) |
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123 | (9) |
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124 | (6) |
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130 | (1) |
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131 | (1) |
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3.16.4 External Access to Audio Data |
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131 | (1) |
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3.17 Recording and Storage Media |
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132 | (20) |
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132 | (4) |
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136 | (2) |
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138 | (14) |
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3.17.4 Digital Audio Tape (DAT) |
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152 | (1) |
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152 | (7) |
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153 | (2) |
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155 | (2) |
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157 | (1) |
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158 | (1) |
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159 | (1) |
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3.19 Long-Term Preservation |
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159 | (3) |
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162 | (5) |
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164 | (3) |
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167 | (20) |
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167 | (1) |
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168 | (19) |
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4.2.1 Opening an Existing File |
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169 | (2) |
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171 | (1) |
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171 | (1) |
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172 | (1) |
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172 | (1) |
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173 | (1) |
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174 | (1) |
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4.2.8 Selection in the Presence of Labels |
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175 | (1) |
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175 | (3) |
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178 | (3) |
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4.2.11 Spectrogram and Spectrum Analysis |
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181 | (1) |
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182 | (4) |
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186 | (1) |
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187 | (24) |
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187 | (2) |
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189 | (1) |
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190 | (1) |
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190 | (2) |
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191 | (1) |
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191 | (1) |
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191 | (1) |
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191 | (1) |
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5.5 Microphones and Sound Fields |
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192 | (1) |
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193 | (3) |
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5.7 Directional Response Pattern |
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196 | (2) |
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198 | (1) |
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199 | (1) |
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5.10 Micromachined Microphones |
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200 | (1) |
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5.10.1 Frequency Response |
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201 | (1) |
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5.11 Audiometric Earphones |
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201 | (5) |
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5.12 Omnidirectional Sources |
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206 | (5) |
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209 | (2) |
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6 Digital Signal Processing |
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211 | (20) |
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211 | (1) |
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211 | (2) |
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6.3 A Signal as Its Convolution with a Discrete Impulse |
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213 | (1) |
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213 | (1) |
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6.5 Finite- and Infinite-Impulse-Response Systems |
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214 | (1) |
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6.6 Difference Equation of a Discrete System |
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215 | (2) |
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6.7 Frequency Response of a Discrete System |
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217 | (2) |
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6.8 z Transform of a Discrete Signal |
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219 | (1) |
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6.9 z Transform of a Difference Equation |
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220 | (2) |
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6.10 z Transform of a Convolution |
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222 | (1) |
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6.11 z Transform and Frequency Response |
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222 | (1) |
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6.12 Solution of a Difference Equation |
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223 | (2) |
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6.13 Poles and Stability of a Discrete System |
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225 | (1) |
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6.14 Inversion of a Rational z Transform |
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225 | (1) |
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6.15 Continuous- to Discrete-System Bilinear Conversion |
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226 | (5) |
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230 | (1) |
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7 Basic Algorithms for Acoustical Measurements |
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231 | (14) |
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231 | (1) |
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232 | (1) |
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7.3 Energy Average and Equivalent Level |
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232 | (1) |
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233 | (1) |
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234 | (2) |
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236 | (3) |
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239 | (6) |
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243 | (2) |
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245 | (52) |
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245 | (1) |
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8.2 Spectrum Analysis Paradigms |
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245 | (1) |
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246 | (5) |
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8.4 Discrete Fourier Transform (DFT) |
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251 | (2) |
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8.5 Fast Fourier Transform (FFT) |
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253 | (1) |
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8.6 Spectrum Analysis with the FFT |
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254 | (14) |
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8.6.1 Line Spectrum Analysis |
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255 | (1) |
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8.6.2 The Problem of Frequencies Close to Fs/2 |
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256 | (2) |
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8.6.3 The Problem of Subharmonic Frequencies |
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258 | (1) |
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8.6.4 Precise Detection of Pure Tones |
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259 | (1) |
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260 | (4) |
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8.6.6 FFT Band Spectrum Analysis |
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264 | (3) |
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8.6.7 Spectral Density and Spectrum Averaging |
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267 | (1) |
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268 | (5) |
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8.8 Some Applications of the FFT |
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273 | (7) |
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8.8.1 Determination of Tonality |
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273 | (2) |
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275 | (3) |
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278 | (1) |
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8.8.4 Critical Band Filters |
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279 | (1) |
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8.8.5 Determination of Transfer Functions |
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280 | (1) |
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8.9 Contrasting Algorithms for Use in Measurements |
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280 | (11) |
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8.9.1 International Standard IEC 61260 |
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281 | (1) |
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8.9.2 Contrasting Algorithms |
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282 | (1) |
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283 | (1) |
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8.9.4 Sound Card Calibration |
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283 | (1) |
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8.9.5 Verification of the Analyzer Response |
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284 | (1) |
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8.9.6 Contrasting Different Algorithms |
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285 | (1) |
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286 | (5) |
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291 | (6) |
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294 | (3) |
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9 Testing Digital Recorders |
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297 | (12) |
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297 | (1) |
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9.2 Specifications of the Digital Recorder |
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298 | (1) |
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298 | (11) |
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298 | (2) |
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300 | (1) |
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301 | (1) |
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302 | (1) |
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303 | (1) |
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304 | (1) |
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305 | (2) |
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307 | (2) |
Appendix A Glossary and Definitions on Metrology |
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309 | (12) |
Appendix B Fundamentals of Statistics |
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321 | |