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Crop price insurance can reduce losses from price volatility for crop producers, but pricing is one paramount important issue. The objective of this research is to provide a tentative method for pricing of crop price insurance with data from the futures market.

With weekly settlement price of January corn futures from the second week of January 2009 to the fourth week of April 2020 in China, we assume that corn futures price follows fractional Brownian motion, and apply an improved Black model.

Our results reveal that the proposed model can be used to yield a fair premium and crop price insurance with varying insured prices and gradient coverage ratios can be used to meet the divergent needs of farmers at an affordable cost for price risk management purposes.

Results can be fine-tuned by extending research to crops such as wheat and rice, and by modeling price volatility with data from options market.

This study offers one plausible way to rate crop price insurance using data from the futures market, and thus adds to this thread of literature by incorporating fractional Brownian motion into an improved Black model.

This study aims to improve the lubrication performance of molybdenum disulfide powders at textured surface of cemented carbide materials, a squeeze motion of vibration assistance method was introduced and investigated.

Surface texture was fabricated on YT15 cemented carbide samples using a laser marking machine. After that, a tribological experiment was carried out on a self-built friction testing machine under different amplitude and frequency of squeeze motion conditions. Moreover, a simulation model was also established to verify the principle of squeeze motion on the lubrication performance improving of MoS₂ particles at textured interfaces.

Analysis results indicated that surface texture on test sample can increase the storage ability of solid lubrication particles, and the lubrication film at the contact interface is more easily formed due to the reciprocating action. Squeeze motion can improve the storage ability of it due to an intermittent contact, which provides an opportunity for MoS₂ particles infiltration, and then a more uniform distribution and load-bearing properties of force chain are also established and formed simultaneously. Thus, a better tribological performance at the contact interface is obtained.

The main contribution of this work is to provide a reference for the molybdenum disulfide powder lubrication with textured surface of cemented carbide materials.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-05-2024-0166/