Understanding the timing of economic feasibility: The case of input interfaces for human-computer interaction

The objective of this paper is to understand when new types of input interfaces for Human–Computer Interaction (HCI) such as Natural User Interfaces (NUI) (e.g., speech and gesture) and Direct Neural Interfaces (DNI), or combinations of them, might become technologically and economically feasible. This problem is addressed by analyzing the performance trajectories of key components in these HCI systems. In the case of speech interfaces, we observe that microphones and automated speech recognition systems are no longer experiencing rapid improvements along key dimensions of performance, which inhibits their technical and economic feasibility. On the other hand, 2D image sensors and depth sensors, which constitute the core components of gesture interfaces, are continuing to improve at a significant rate in terms of characteristics like spatial resolution, pixel sensitivity, and depth resolution. When coupled with the exponential improvements in the memory and processing power of computing systems, the above improvements in image sensors are enabling gesture-based natural user interfaces to reach acceptable levels of technical performance and economic feasibility. Similarly, simultaneous improvement in the spatial and temporal resolution of non-invasive brain scanning technologies is likely to accelerate the development of direct neural interfaces (DNI). However, a number of challenging obstacles such as lack of robust magnetic shielding systems, high cost, and poor usability continue to hinder the economic feasibility of DNI systems.     

沥青四组分测定条件对结果的影响

沥青的化学组成决定了沥青的使用性能,但是沥青部分物化性能的测定属条件试验,由于在具体试验过程中没有严格按照操作条件进行,导致沥青的化学组成与其使用性能关联性较差.研究通过对比试验,考察了石油沥青组分测定过程中氧化铝的水含量、沉淀沥青质所用溶剂的用量以及冲洗剂的用类等对测定结果的影响.试验结果表明:石油沥青组分测定法是条件试验,改变试验条件将会影响试验的测定结果.     

汽车结构件的压铸

汽车结构件具有很高的力学性能要求和本体品质要求,采用压铸工艺生产难度大。针对汽车结构件特点和多年经验,开发了汽车结构件压铸工艺。该工艺主要涉及压铸机、压铸模具、合金材料、合金液处理、真空应用、工艺优化等因素。生产实践证明,正确处置上述工艺因素,完全可以在通用压铸机上生产出合格的结构件。     

DNA微阵列数据特征提取的分类方法研究

常用的排列方法从DNA微数据中选择的基因集合往往会包含相关性较高的基因,而且使用单个基因评价方法也不能真正反映由此得到的特征集合分类能力的优劣。另外,基因数量远多于样本数量是进行疾病诊断面临的又一挑战。为此,提出一种DNA微阵列数据特征提取方法用于组织分类。该方法运用K-means方法对基因进行聚类分析,获取各子类DNA微阵列数据中心,用排列法去除对分类无关的子类,然后利用ICA方法提取剩余子类集合的特征,用SVMs方法构造分类器对组织进行分类。真实的生物学数据实验表明,该方法通过提取一种复合基因,能综合评价基因分类能力,减少特征数,提高分类器的分类准确性。     

蛇纹石有价成分的提取与富集

蛇纹石作为一种重要的非金属矿物,广泛用于多种工业领域。本文介绍了蛇纹石的基本性质和结构,综述了国内外蛇纹石有价成分提取和富集的研究现状,主要介绍了氧化镁、氢氧化镁等镁系列产品、硅系列产品以及重金属镍和贵金属钯提取工艺。系统介绍了镍的提取技术,如还原焙烧—磁选法、还原焙烧—氨浸法、常压酸浸法和加压酸浸法等。提出了开发综合利用蛇纹石的重要意义及相关研究方向。     

茶树籽和油茶籽中脂溶性化学成分的比较研究

收集24个不同品种的成熟茶树籽和油茶籽样品,分析出仁率、脂肪、脂肪酸组成以及角鲨烯和β-谷甾醇等脂溶性化学成分状况。结果表明,13个油茶籽样品中,平均出仁率、脂肪、棕榈酸、棕榈烯酸、硬脂酸、油酸、亚油酸、亚麻酸、顺-11-二十碳烯酸分别为70.1%、51.7%、13.8%、0.1%、3.1%、72.7%、9.4%、0.6%、0.4%,而11个茶树籽中平均值分别为64.2%、31.6%、14.7%、0.1%、2.7%、59.2%、21.8%、0.4%、1.0%。油茶籽中角鲨烯含量为61.3~296.1 mg/kg,茶树籽的则为17.2~227.0 mg/kg。油茶籽中角鲨烯平均含量149.0 mg/kg为茶树籽平均112.5 mg/kg的1.32倍。茶树籽中β-谷甾醇含量为313.3~558.1 mg/kg,油茶籽中则为52.6~122.8 mg/kg。前者平均值443.3 mg/kg为后者80.8 mg/kg的5.5倍。通过相关分析,油酸与单不饱和脂肪酸,亚油酸与多不饱和脂肪酸,均呈现绝对正相关。通过聚类分析,茶树籽与油茶籽能很好地被区分成两大类。     

近红外光谱法快速预测烟梗中常规化学成分的研究

采用近红外光谱法对烟梗中常规化学成分进行快速预测,其相对误差较小,预测能力和稳定性较好,具备推广价值。     

Two Projection Methods for Use in the Analysis of Multivariate Process Data With an Illustration in Petrochemical Production

Principal components analysis (PCA) is often used in the analysis of multivariate process data to identify important combinations of the original variables on which to focus for more detailed study. However, PCA and other related projection techniques from the standard multivariate repertoire are not explicitly designed to address or to exploit the strong autocorrelation and temporal cross-correlation structures that are often present in multivariate process data. Here we propose two alternative projection techniques that do focus on the temporal structure in such data and that therefore produce components that may have some analytical advantages over those resulting from more conventional multivariate methods. As in PCA, both of our suggested methods linearly transform the original p-variate time series into uncorrelated components; however, unlike PCA, they concentrate on deriving components with particular temporal correlation properties, rather than those with maximal variance. The first technique finds components that exhibit distinctly different autocorrelation structures via modification of a signal-noise decomposition method used in image analysis. The second method draws on ideas from common PCA to produce components that are not only uncorrelated as in PCA, but that also have approximately zero temporally lagged cross-correlations for all time lags. We present the technical details for these two methods, assess their performance through simulation studies, and illustrate their use on multivariate output measures from a fluidized catalytic cracking unit used in petrochemical production, contrasting the results obtained with those from standard PCA.     

跨越既有线路的大跨度钢箱梁架设技术探讨

钢箱梁具有拼装快、自重轻、跨度大、承载能力高、便于维修的特点,在高速公路桥梁工程中日益受到重视。现结合西安某高速公路匝道桥跨越西三高速公路处钢箱梁架设的实例,从架设方案、控制措施、受力分析等方面进行了详细计算和论证,可为大跨径钢箱梁架设施工提供参考。     

缓解女性生理期疼痛的内裤设计及性能评价

为开发缓解女性生理期腹部疼痛且适用于日常穿着的功能性智能内裤,应用感性工学原理,访谈20名女性目标人群,确定基本设计要素。基于人体工程学和中医针灸学原理,确定内裤的腹部功能位置,并采用嵌入式工艺将柔性纳米增强远红外芯片制作在内裤腹部功能位置。经远红外热像分析得出,柔性纳米增强远红外内裤腹部渗入人体穴位温度达到25.8℃,并刺激按摩穴位;经穿着评价试验得出,穿着该内裤5天可以显著缓解生理期腹部疼痛。