改进卷积输入的端到端普通话语音识别

主流神经网络训练的交叉熵准则是对声学数据的每个帧进行分类优化，而连续语音识别是以序列级转录准确性为性能度量。针对这个不同，构建基于序列级转录的端到端语音识别系统。针对低资源语料条件下系统性能不佳的问题，其中模型使用卷积神经网络对输入特征进行处理，选取最佳的网络结构，在时域和频域进行二维卷积，从而改善输入空间中因不同环境和说话人产生的小扰动影响。同时神经网络使用批量归一化技术来减少泛化误差，加速训练。基于大型的语言模型，优化解码过程中的超参数，提高模型建模效果。实验结果表明系统性能提升约24%，优于主流语音识别系统。     

云南铜厂沟铜钼矿低贫损分段崩落与浅孔留矿耦合采矿法探索

铜厂沟矿区多为破碎、中厚、急倾斜矽卡岩型铜钼矿体，原设计采用上向水平分层充填采矿法，在采矿实验中存在作业安全性差、劳动生产效率低、损失贫化大、采矿成本高等缺陷，严重制约了试生产组织。矿山急迫需要一种安全、高效、成本能够控制的采矿方法满足试生产矿石持续供应。通过充分研究，提出了低贫损分段崩落与浅孔留矿耦合采矿方法的设想，进一步降低了安全风险、简化工艺、控制损失贫化等。通过采矿方法的优化设计，解决了企业生产存在的实际问题，提高了采矿效率，对其它同类矿山具有一定的参考借鉴意义。     

张庄铁矿高阶段矿房切割天井施工工艺试验

张庄铁矿设计采矿方法为大直径深孔阶段空场嗣后充填法。为了最大化发挥采矿设备性能，降低采切工程量，提高回采效率，通过实施一系列技术攻关，实现了将采矿阶段高度由原来的60 m提高到90 m。而作为最初爆破回采的自由面及爆破补偿空间，切割天井施工工艺为影响高阶段矿房爆破回采效果的关键因素，施工质量的优劣，直接影响矿房爆破回采生产作业能否顺利进行，而二次处理在增加施工成本的同时将带来安全隐患。张庄铁矿在面临可参考的成熟经验较少的情况下，结合现场可用的作业条件采取了对比试验的方法，在安全、技术及经济多方面综合分析比较下，确定了最终方案，为张庄铁矿安全稳定生产奠定了基础，同时研究成果可为大型地下矿山生产实践提供一定的参考。     

高压并联电抗器噪声影响因素及其控制措施研究

文中针对变电站高压并联电抗器噪声对环境的影响问题及其控制要求,通过实验研究了高压并联电抗器噪声的影响因素及其控制措施。文中采用改进声强法实测了湖北省内15座变电站37组共111台500 kV高压并联电抗器声功率级,并对其进行了分析。测试结果表明,随着运行年限的增加,电抗器最大声功率级逐步增大。由于设备额定容量与额定电压的提高,使用新的绝缘材料和设计方案后,在一定程度上会起到减震降噪作用。同时,电抗器采用散热片四周布置方式,也能实现对噪声的控制。针对高压电抗器的噪声控制,文中从声源控制、传播过程控制角度,提出相应的控制措施。其中,声源主要通过改善材料和设计进行控制。以某500 kV变电站的降噪处理为例,利用SoundPLAN噪声分析软件,提出了隔声屏障控制方案,使噪声平均声压级降低约6 dB(A),从而满足噪声控制的要求。文中的研究内容对于指导变电站的设计及降噪处理具有重要意义。     

Monitoring water level and volume changes of lakes and reservoirs in the Yellow River Basin using ICESat-2 laser altimetry and Google Earth Engine

Monitoring the water level and volume changes of lakes and reservoirs is essential for deepening our understanding of the temporal and spatial dynamics of water resources in the Yellow River Basin, with a view to better utilizing and managing water resources. In recent years, there have been many studies on monitoring water level and volume changes in inland waters, but they were mainly focused on radar altimetry and the full waveform LiDAR ICESat, which was retired in 2010. Few studies based on the latest photon-counting LiDAR ICESat-2 have been reported. Compared with previous sensors, ICESat-2 has great advantages in footprint size, transmitting frequency, pulse number, etc, but its performance in monitoring water level and volume changes in inland waters has not been fully explored. Here we investigated the spatial distribution of water level and volume changes of 11 lakes and 8 reservoirs in the Yellow River Basin based on ICESat-2 and Google Earth Engine, and analyzed the factors affecting the measurement uncertainties. In-situ validation of lake level in Lake Qinghai indicates that the Root Mean Square Error (RMSE) of our result is only 7 cm after the reference coordinate system conversion. We found that the water level trend of the natural lake shows significant seasonal variations, while the water level trend of the reservoir shows a sharp rise and fall. In addition, precipitation plays a decisive role in the changes in natural lake levels and indirectly affects the artificial control of reservoirs’ water discharges. The uncertainty of water volume change monitoring is mainly affected by water level measurement uncertainty for lakes, while for reservoirs, that is affected by the combination of water level and area measurement uncertainties. The stability of lake level measurement increases with the increase in photon counts. The introduction of ICESat-2 ATL13 Significant Wave Height might lead larger standard deviation in water level measurement. According to the law of propagation of uncertainty, the uncertainty of the water volume change estimation by the combination of ICESat-2 and GEE is less than 9 %.     

混砂设备中液位控制系统算法研究

在对国、内外混砂设备的控制特性进行调研和深入研究的基础上,对混砂设备的液位控制系统对象特性进行了分析,建立了相应的数学模型,并提出相应的控制方案,以模糊PID的复合控制方法来改进控制效果。根据室内和工业测试,该算法取得了预期效果。     

侏罗系煤层顶板砂岩水采动下动态模拟研究

以鄂尔多斯东胜区的泊江海子煤矿为例,根据对采前煤层顶板的白垩系及侏罗系砂岩裂隙-孔隙水赋存特征及采动过程中地下水动态特征分析,从机理上揭示顶板砂岩水的赋存规律及影响因素。然后,在研究侏罗系煤系含水层水文地质条件基础上,通过Visual Modflow,建立水文地质概念模型与数学模型,研究工作面推进过程中,不同疏水量下的地下水流场动态变化特征,探讨采动下的裂隙-孔隙水出水规律,为矿区砂岩水害的防治提供依据。     

Circulating YKL-40 Level,but not CHI3L1 Gene Variants,Is Associated with Atherosclerosis-Related Quantitative Traits and the Risk of Peripheral Artery Disease

YKL-40, a pleotropic cytokine, is emerging as a risk factor and a prognostic predictor of atherosclerotic cardiovascular disease. We attempted to elucidate the genetic, clinical and biochemical correlates of circulating YKL-40 level and, by combining it with CHI3L1 gene variants, with the risk and long-term mortality of peripheral artery disease (PAD). Plasma YKL-40 concentrations were measured in 612 Taiwanese individuals who had no clinically overt systemic disease. Clinical parameters, CHI3L1 gene promoter variants and 18 biomarker levels were analyzed. Eighty-six PAD patients were further enrolled for analysis. Significant associations were found between CHI3L1 genotypes/haplotypes and YKL-40 levels for the health examination subjects (smallest p = 8.36 × 10⁻⁷ for rs4950928 and smallest p = 1.72 × 10⁻¹⁰ for haplotype TGG) and also for PAD patients. For the health examination subjects, circulating YKL-40 level, but not CHI3L1 gene variants, were positively associated with age, smoking, and circulating levels of triglyceride, lipocalin 2 and multiple inflammatory biomarkers and negatively associated with low-density-lipoprotein cholesterol levels. Circulating YKL-40 level is also significantly associated with the risk of PAD (p = 3.3 × 10⁻²³). Circulating YKL40 level, but not CHI3L1 gene promoter variants, is associated with the risk of PAD in Taiwanese. The association of YKL-40 levels with multiple quantitative traits relating to the risk of PAD may provide a molecular basis linking YKL-40 to atherosclerotic cardiovascular disease.     

国际人造金刚石行业近期发展态势（上）

人造金刚石的应用从最初的工业应用领域发展到宝石级人造金刚石用于珠宝行业然后又发展到纪念品钻石服务于丧事家庭和特殊礼品等。文章阐述了工业用人造金刚石、宝石级人造金刚石与纪念品钻石的最新进展以及工业用人造金刚石在高科技与各工业部门的最新应用。全面反映国际工业用人造金刚石、宝石级人造金刚石和纪念品钻石技术的当前发展水平以及人造金刚石的未来发展趋势。此外,对国际上主要的工业用人造金刚石生产企业以及宝石级人造金刚石与纪念品钻石生产厂家的发展作简单介绍。