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Located in Baoding, northern China’s Hebei Province, the Daqing River Basin faces a nonnegligible problem: the prevention and control of ice damage in the South-to-North Water Diversion Project (SNWDP) during the ice period. This paper sorts out the observation data on the ice conditions in river sections of the Daqing River Basin in winter, 1994–1997, and calculates the roughness of the water transmission sections, through mathematical calculation and inverse computation. On this basis, the authors analyzed the influence of ice caps on the flow capacity of river channel, and discussed the effects of water level variation on ice cap stability. The results show that, during the ice period, the ice caps in the upstream of the water transmission channel in the river basin are rougher than those in the downstream. In the same river section, the ice caps are rougher in the initial phase than the late phase. At the same water level, the flow capacity of different sections reduces by 40–61% under ice caps. For the entire river channel, the ice caps lower the flow capacity by 40–52%. The water level variation has a huge influence of ice cap stability. During the ice period, the flow should be maintained stable to transmit water under ice caps. This helps to stabilize water level, ensure the continuity and completeness of ice caps, and improve the water transmission efficiency in the ice period.

Elastic warp-knitted composite fabrics with far-infrared emissivity and an anion-releasing property were prepared using bamboo charcoal (BC), copper (Cu), and phase-change material (PCM). The functional composite fabric, which was composed of self-made complex yarns with various twisting degrees and material composition, were created using a rotor twister and ring-spinning technique. The fabric structure was diversified by the feeding modes of weft yarn into a crochet-knitting machine. The twist number of complex yarns was optimized by tensile tenacity, twist contraction, and hairiness, and analysis showed that twisting at 12 twists per inch produced the highest tensile tenacity and appropriate twist contraction and hairiness. Comfort evaluation showed that the elastic composite fabrics with BC weft yarns exhibited higher water–vapor transmission rate and air permeability, reaching 876 g/m2∙ day and 73.2 cm3/s/cm2, respectively. Three structures of composite fabric with various weft yarns had >0.85 ε far-infrared emissivity and 350–420 counts/cm3 anion amount. The prepared elastic warp-knitted fabrics can provide a comfortable, dry, and breathable environment to the wearer and can thus be applied as health-care textiles in the future.