Resonance frequency drift caused by a change in temperature greatly limits the application of high- Q resonators with high temperature sensitivity in photoacoustic (PA) gas detection systems. In this work, a chirp-wavelength combined modulation method was designed by incorporating a real-time frequency scanning in wavelength-modulated PA spectroscopy to reduce the influence of temperature changes on measurement. Theoretical analysis shows that the chirp rate depends on the precision requirements and the cutoff frequency of the cascaded low-pass filter. Trace acetylene measurement experiment at varying temperature verified that the proposed method can significantly reduce the temperature sensitivity within a preset temperature range. Thus, this method can effectively reduce the temperature sensitivity of a high- Q resonator for improving the measurement accuracy and detection limit in trace gas detection.

Thomas Kuhn's paradigm theory tells us that the science itself has a certain structure and the development of science has its own laws. His historicism research methodology in philosophy of science provides us a research approach having much referential values for investigating, predicting and programming the process and prospect of the development of Unified Information Science. And the paradigm shift of science firstly needs a breakthrough in its philosophical core-ontological presupposition. Therefore, this article will discuss how the development of Information Philosophy in China provides an opportunity for building the Unified Information Science from the perspective of paradigm theory, analyzing what necessary theoretical foundations that paradigm theory provides for the

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