不同展叶物候期胡杨离子分布、吸收和运输特征及其与土壤盐分关系

为明确胡杨的离子分布、吸收和运输规律,探讨胡杨适应盐渍环境的生理机制,以不同展叶物候期(萌芽期、展叶期、叶片快速发育期、叶片成熟期)的胡杨(Populus euphratica)为研究对象,测定各器官中的可溶性盐离子并分析离子吸收、运输和分配特征,结合林下土壤盐分,探讨胡杨离子分布与土壤盐分关系。结果表明,随着展叶物候的变化,胡杨通过对离子吸收、运输和分布规律的差异满足生长发育的需要及对环境的适应。(1)根系选择性吸收K^(+)、Ca^(2+)和Mg^(2+)的能力随展叶物候变化呈先升后降趋势,以叶片快速发育期为最高,与土壤中总盐及Na^(+)、Cl^(-)含量变化趋势相反;(2)离子从根系-主干及幼枝-叶片的运输能力随展叶物候的变化表现为先降后升的相反趋势,且以叶片快速发育期为最低;(3)各器官中Na^(+)和K^(+)含量在展叶过程中变化不大,在叶片成熟期有显著升高,且Na^(+)以根中含量最高,K^(+)以叶片中含量最高,叶片和根系中Ca^(2+)、Mg^(2+)含量随展叶物候变化整体呈升高趋势;(4)展叶物候期胡杨器官离子与土壤离子相关性表现为:萌芽期,各器官离子含量受土壤盐分影响较小,指标间相关性多不显著;展叶期,根中Na^(+)与土壤离子呈正相关,幼枝和主干K^(+)与土壤多呈负相关;叶片快速发育期,幼枝Mg^(2+)、根中Na^(+)均与土壤离子呈正相关;叶片成熟期,各器官离子含量受土壤离子影响较小。

Implementation of encoder and decoder for LDPC codes based on FPGA

This paper proposes a parallel cyclic shift structure of address decoder to realize a high-throughput encoding and decoding method for irregular-quasi-cyclic low-density parity-check(IR-QC-LDPC)codes,with a dual-diagonal parity structure.A normalized min-sum algorithm(NMSA)is employed for decoding.The whole verification of the encoding and decoding algorithm is simulated with Matlab,and the code rates of 5/6 and 2/3 are selected respectively for the initial bit error ratio as 6%and 1.04%.Based on the results of simulation,multi-code rates are compatible with different basis matrices.Then the simulated algorithms of encoder and decoder are migrated and implemented on the field programmable gate array(FPGA).The 183.36 Mbps throughput of encoder and the average 27.85 Mbps decoding throughput with the initial bit error ratio 6%are realized based on FPGA.

基于大型语言模型微调技术的反诈骗信息识别方法研究

针对反诈骗信息识别,对大型语言模型(LLMs)的微调技术进行了深入的实验研究。选取了3种不同规模的LLMs基础模型,并采用了LoRA和p-tuningv22种先进的微调技术,以适应特定的反诈骗信息识别任务。通过多个维度的实验评估,微调策略不仅能够显著提升模型在反诈骗信息识别上的性能,还能够在一定程度上保持模型的通用性。此外,探讨了LLMs在少样本情况下的学习能力,并分析了不同微调策略下的资源消耗情况。

Experimental validation of dynamic polarization compensation in ground-satellite quantum key distribution

Ground-satellite quantum key distribution(QKD)is a feasible way to implement global-scale quantum communication.Herein we propose an approach to dynamically compensate the polarization of the photons when passing through the optical telescope used in ground-satellite QKD.Our results experimentally demonstrate that the fidelity of any polarization state after dynamic compensation can be achieved by more than 99.5%,which fulfills the requirements of ground-satellite QKD.