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An interferogram is produced by modulating the difference between the extraordinary refractive index and the ordinary refractive index for photoelastic crystals in photoelastic-modulated Fourier transform spectrometers (PEM-FTs). Due to the influence of the refractive index dispersion characteristics on the maximum optical path difference of the interferogram, it is necessary to study wavelength calibration methods.

A wavelength calibration method for PEM-FTs was proposed based on the modulation principle of the photoelastic-modulated interferometer and the relationship between the maximum optical path difference and the refractive index difference. A 632.8 nm narrow-pulse laser was used as a reference source to measure the maximum optical path difference () of the interferogram, and the parameter was used to calculate the discrete frequency points in the frequency domain. To account for the influence of refractive index dispersion on the maximum optical path difference, the refractive index curve for the photoelastic crystal was used to adjust the discrete frequency coordinates.

The error in the reconstructed spectral frequency coordinates clearly decreased. The maximum relative error was 2.5%. A good solar absorption spectrum was obtained with a PEM-FT experimental platform and the wavelength calibration method.

The interferogram is produced by adjusting the difference between extraordinary refractive index and ordinary refractive index for the photoelastic crystal in the PEM-FTs. Given the wavelength dependence on the refractive indices, in view of the modulation principle of the photoelastic modulated interferometer, the relationship between the maximum optical path difference and the refractive index difference, the variation law of the refractive index of the photoelastic crystal and the process of spectral reconstruction is presented in this paper.

The purpose of this paper is to assess how spatial heterogeneity and production diversification have affected the efficiency of households participating in the SLCP.

Based on household survey data collected from three sample counties in the Loess Plateau region, the paper analyzes how spatial heterogeneity and business diversification have affected the production efficiency of households participating in the SLCP. Using four-step bootstrap, input stochastic distance frontiers of multi-inputs and multi-outputs are developed simultaneously with a technical efficiency effects model in which participating in the SLCP is treated as an exogenous variable.

The household production in the three counties is constrained by land, labor, capital, and fixed inputs; thus, it is germane to using a multi-input and multi-output household production technology to evaluate the SLCP. However, the relative importance of each input and output, the productive diversification, and the technological structure are differentiated in the three counties; estimating the regression with pooled data appears to conceal the influences of local factors and blur the specific divergence, compared to running county-based, separate regressions.

The effects of the SLCP on farm household production are location dependent. It is necessary to include spatial heterogeneity within public policy evaluation. In addition to suggesting localized and differentiated schemes of subsidy, this implies that the government may provide means to facilitate different regions to make the economic transition.

This paper intends to make two contributions. First, the analysis will capture and explain the adjustments induced by the SLCP in off-farm and other activities for entire household production, and special attention is given to the diversification of household production outputs. Second, this analysis sheds new light to the significance of spatial differentiation in mediating the effectiveness of a public policy or program.

The purpose of this paper is to illustrate a for-credit information literacy course redesign that used a flexible multimodal framework to address individual student learning preferences, personal differences and abilities as well as teaching preferences.

Students taking the course were surveyed as to their preferences for content delivery. A qualitative analysis of student reflections was conducted to determine the efficacy of maintaining multiple course formats and to solicit feedback for course improvements.

Results show that students were definitive in their preferences for how they access course materials and that enough students used each format to justify maintaining both. Findings also showed students’ appreciation for being given options.

Content delivery modes are changing rapidly. Future studies should explore the efficacy of other modes of delivery.

As technology and students’ familiarity with course delivery modes change, how we deliver content to students will also change. The key to reaching students in an effective manner is flexibility.

Exploring why and how students choose to learn provides valuable feedback into how we should or should not deliver course content. Learning what works, and providing multiple options, will increase the likelihood of success for a diverse student body.

Degradable mulch film (DMF) is a potential alternate to polyethylene (PE) mulching. In this regard, the purpose of this paper is to explore the effects and paths of natural disaster shock and risk aversion influencing farmers’ DMF adoption.

This research is conducted by collecting cross-sectional data of corn farmers in Zhangye, China. First, by using the Tobit model, the paper attempts to explore the effects of natural disaster shock and risk aversion influencing farmers’ DMF adoption. Second, IV-Tobit model is applied to deal with endogenous problems between risk aversion and DMF adoption. Additionally, the researchers used a moderating model to analyze feasible paths of natural disaster shock and risk aversion impacting farmers’ DMF adoption.

The outcomes show that natural disaster shock and risk aversion significantly and positively affect farmers’ DMF adoption. Though risk aversion plays a significant moderating effect in influencing farmers’ DMF adoption by natural disaster shock, the moderating effect has a serious disguising effect. By considering the heterogeneity of risk aversion, the paper further confirms that if the intensity of natural disaster shock is increased by one unit, the intensity of MDF adoption by farmers with high-risk aversion also tends to increase by 15.85%.

This study is the pioneer one, which is evaluating the intensity of farmers’ DMF adoption from adoption ratio, investment amount, labor input and adoption time. Additionally, the research provides important guidelines for policymakers to motivate medium and low-risk aversion farmers to adopt DMF.