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991.
新型国产近红外分析仪的菜籽菜粕快速检测技术研究 总被引:3,自引:0,他引:3
近红外光谱分析作为1种快速无损的绿色分析技术,可应用于检测油料原料和油脂产品品质,为粮油企业带来巨大经济效益.本文采用一款新型国产化的近红外漫反射光谱分析仪对菜籽和菜粕进行了检测分析,分别对菜籽的水分、蛋白、含油量、脂肪酸、硫苷含量和菜粕水分、蛋白和含油量指标建立模型并验证.结果显示近红外检测结果与国标参考方法检测结果相关性好、准确度高.表明新型国产化的近红外分析仪可满足油脂企业对菜籽和菜粕产品的质量控制要求. 相似文献
992.
Synthesizing the movements of a responsive virtual character in the event of unexpected perturbations has proven a difficult challenge. To solve this problem, we devise a fully automatic method that learns a nonlinear probabilistic model of dynamic responses from very few perturbed walking sequences. This model is able to synthesize responses and recovery motions under new perturbations different from those in the training examples. When perturbations occur, we propose a physics‐based method that initiates motion transitions to the most probable response example based on the dynamic states of the character. Our algorithm can be applied to any motion sequences without the need for preprocessing such as segmentation or alignment. The results show that three perturbed motion clips can sufficiently generate a variety of realistic responses, and 14 clips can create a responsive virtual character that reacts realistically to external forces in different directions applied on different body parts at different moments in time. 相似文献
993.
图的可达性查询被广泛应用于生物网络、社会网络、本体网络、RDF网络等.由于对数据操作时引入的噪声和错误使这些图数据具有不确定性,而确定图的可达查询不能有效地处理不确定性,因此该文研究用概率语义描述的图可达性查询.具体的,该文使用可能世界概率模型定义不确定图(称为概率图),基于该模型,研究了基于阈值的概率可达查询(T-PR).首先为避免枚举所有可能世界,给出一个基本算法可精确求解T-PR查询.其次为进一步加速基本算法,给出3种改进方法,它们是不确定事件界、同构图的缩减、基于不相交路径和割集的界.通过合理的组合给出3种方法的合并算法.最后基于真实概率图数据的大量实验验证了该文的设计. 相似文献
994.
Abstract: Using a conjugate gradient method, a novel iterative support vector machine (FISVM) is proposed, which is capable of generating a new non‐linear classifier. We attempt to solve a modified primal problem of proximal support vector machine (PSVM) and show that the solution of the modified primal problem reduces to solving just a system of linear equations as opposed to a quadratic programming problem in SVM. This algorithm not only has no requirement for special optimization solvers, such as linear or quadratic programming tools, but also guarantees fast convergence. The full algorithm merely needs four lines of MATLAB codes, which gives results that are similar to or better than that of several new learning algorithms, in terms of classification accuracy. Besides, the proposed stand‐alone approach is capable of dealing with instability of classification performance of smooth support vector machine, generalized proximal support vector machine, PSVM and reduced support vector machine. Experiments carried out on UCI datasets show the effectiveness of our approach. 相似文献
995.
Fisher discriminant analysis gives the unsatisfactory results if points in the same class have within-class multimodality
and fails to produce the non-negativity of projection vectors. In this paper, we focus on the newly formulated within and
between-class scatters based supervised locality preserving dimensionality reduction problem and propose an effective dimensionality
reduction algorithm, namely, Multiplicative Updates based non-negative Discriminative Learning (MUNDL), which optimally seeks
to obtain two non-negative embedding transformations with high preservation and discrimination powers for two data sets in
different classes such that nearby sample pairs in the original space compact in the learned embedding space, under which
the projections of the original data in different classes can be appropriately separated from each other. We also show that
MUNDL can be easily extended to nonlinear dimensionality reduction scenarios by employing the standard kernel trick. We verify
the feasibility and effectiveness of MUNDL by conducting extensive data visualization and classification experiments. Numerical
results on some benchmark UCI and real-world datasets show the MUNDL method tends to capture the intrinsic local and multimodal
structure characteristics of the given data and outperforms some established dimensionality reduction methods, while being
much more efficient. 相似文献
996.
Social reciprocity deficits are a core feature of the autism spectrum conditions (ASCs). Many individual with ASCs have difficulty with social interaction due to a frequent lack of social competence. This study focuses on using a virtual learning environment to help the deficiencies of social competence for people with ASCs, and to increase their social interaction. Specifically, it primitively explores social competence in collaborative virtual learning environment (CVLE) systems, and behavioral performance in social and cognitive interactions. Thus, this CVLE-social interaction system involves a 3D expressive avatar, an animated social situation, and verbal as well as text-communication. A preliminary empirical study involved CVLE-social interaction systems. Three participants who had been diagnosed with ASCs were conducted using a multiple baseline research for evidence of improved social competence through usage of the system. The experimental study consisted of 17 days; and the results showed that using the CVLE-social interaction system had significant positive effects on participants’ performance, both within the CVLE-social interaction system and in terms of reciprocal social interaction learning. 相似文献
997.
A novel dual-mass resonant output micromechanical gyroscope is proposed which utilizes resonant sensing as the basis for Coriolis force detection instead of displacement sensing. It can overcome the shortcoming of single-mass resonant output micromechanical gyroscope and can reduce the common mode acceleration error by using a dual-mass topology structure and lever differential mechanism. The structure and operating principle of the device are introduced. Moreover, some important theoretical analyses of the gyroscope are provided in detail. The analytical results have shown that the resonant frequencies of vibrating mass and double-ended tuning fork resonators are 3.153 and 62.853 kHz. The device has a frequency sensitivity of 12.535 Hz/deg/s and a mechanical noise floor of $ 7.957\deg /{\text{h}}/\sqrt {{\text{Hz}}} A novel dual-mass resonant output micromechanical gyroscope is proposed which utilizes resonant sensing as the basis for Coriolis
force detection instead of displacement sensing. It can overcome the shortcoming of single-mass resonant output micromechanical
gyroscope and can reduce the common mode acceleration error by using a dual-mass topology structure and lever differential
mechanism. The structure and operating principle of the device are introduced. Moreover, some important theoretical analyses
of the gyroscope are provided in detail. The analytical results have shown that the resonant frequencies of vibrating mass
and double-ended tuning fork resonators are 3.153 and 62.853 kHz. The device has a frequency sensitivity of 12.535 Hz/deg/s
and a mechanical noise floor of
7.957deg/\texth/?{\textHz} 7.957\deg /{\text{h}}/\sqrt {{\text{Hz}}} in air. The finite element simulation results verify the accuracy of analytical algorithms. The common mode acceleration
error of device can be reduced by 97.6%. The device is fabricated by SOG (Silicon on Glass) micro fabrication technology.
Some important performances are measured by experimental method. The micromechanical gyroscope can be used to estimate the
rotation rate by further implementing the signal processing electronics. 相似文献
998.
CDMA系统的容量主要受限于系统内移动台的相互干扰,所以如果每个移动台的信号到达基站时都达到最小所需的信干比,系统容量将会达到最大值。在CDMA蜂窝系统中,为了解决远近效应的问题,同时避免对其他用户过大的干扰,必须采用严格的自动功率控制。功率控制的目的就是既维持高质量通信。又不对同一频率的其它用户产生不应有的多址干扰。功率控制的目的是控制每个用户的发射功率,而使得基站接收收到的每个用户的功率接近,从而克服远近效应。 相似文献
999.
为提高移动机器人定位系统的可靠性,设计了组合使用光纤陀螺仪、光电码盘和超声波传感器的定位系统,系统采用CAN总线的数据传输方式。ATmega16采集各传感器数据,再以CAN总线方式传输给PC机;PC机平台综合处理光纤陀螺、光电码盘与超声波返回的数据,实现移动机器人定位。定位算法以航迹推算为主,超声波传感器起辅助定位作用。实验表明定位系统可靠有效。 相似文献
1000.
企业办公自动化系统的应用十分广泛,随着互联网的高速发展,WEB应用成为主流,OA系统在互联网上的延伸成为大趋势,本文阐述在WEB应用中如何保障数据和系统安全的手段和方法。 相似文献