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91.
渗透汽化膜分离技术适合应用于有机溶剂中水的脱除、废水处理与溶剂回收等。。文中根据渗透汽化膜分离的技术特点,对其在石油化工领域的应用进行了分析,该技术能够降低生产过程中的能耗,设备投资费用少,且经济环保。 相似文献
92.
This review highlights the synthesis, physical properties, and emerging technologies of state-of-the-art segmented copolymers containing amide hydrogen bonding sites. Amide hydrogen bonding plays a crucial role in the physical properties associated with amide-containing segmented copolymers. Amide hard segments are accessible in many different forms from amorphous alkyl amides to crystalline aramids and greatly influence copolymer morphology and mechanical properties. Variations in copolymer structure allow for the fine tuning of physical properties and the ability to predict mechanical performance based upon structural modifications. This review includes various synthetic methods for producing well-defined amide-containing segmented copolymers as well as common applications. Also, the morphological and mechanical properties associated with modifications in copolymer structure are discussed. 相似文献
93.
94.
In this paper, the development of the models for the prediction of rock mass P wave velocity is presented. For model development, the database of 53 cases including widely used and recorded drilling parameters and P wave velocity was constructed from the field studies conducted in 13 open pit lignite mines. Both conventional linear, non-linear multiple regression and Adaptive Neuro Fuzzy Inference System (ANFIS) were used for model development. Prediction performance indicators showed that ANFIS model presented the best performance and it can successfully be used for the preliminary prediction of P wave velocities of rock masses. 相似文献
95.
Y. Huang V. Chandran Suja J. Tajuelo G. G. Fuller 《Journal of the Royal Society Interface》2021,18(175)
Droplet interface bilayers are a convenient model system to study the physio-chemical properties of phospholipid bilayers, the major component of the cell membrane. The mechanical response of these bilayers to various external mechanical stimuli is an active area of research because of its implications for cellular viability and the development of artificial cells. In this article, we characterize the separation mechanics of droplet interface bilayers under step strain using a combination of experiments and numerical modelling. Initially, we show that the bilayer surface energy can be obtained using principles of energy conservation. Subsequently, we subject the system to a step strain by separating the drops in a step-wise manner, and track the evolution of the bilayer contact angle and radius. The relaxation time of the bilayer contact angle and radius along with the decay magnitude of the bilayer radius were observed to increase with each separation step. By analysing the forces acting on the bilayer and the rate of separation, we show that the bilayer separates primarily through the peeling process with the dominant resistance to separation coming from viscous dissipation associated with corner flows. Finally, we explain the intrinsic features of the observed bilayer separation by means of a mathematical model comprising the Young–Laplace equation and an evolution equation. We believe that the reported experimental and numerical results extend the scientific understanding of lipid bilayer mechanics, and that the developed experimental and numerical tools offer a convenient platform to study the mechanics of other types of bilayers. 相似文献
96.
97.
In this paper, we offer a method aiming to minimize the role of distance metric used in clustering. It is well known that distance metrics used in clustering algorithms heavily influence the end results and also make the algorithms sensitive to imbalanced attribute/feature scales. To solve these problems, a new clustering algorithm using a per-attribute/feature ranking operating mechanism is proposed in this paper. Ranking is a rarely used discrete, nonlinear operator by other clustering algorithms. However, it also has unique advantages over the dominantly used continuous operators. The proposed algorithm is based on the ranks of the data samples in terms of their spatial separation and is able to provide a more objective clustering result compared with the alternative approaches. Numerical examples on benchmark datasets prove the validity and effectiveness of the proposed concept and principles. 相似文献
98.
活动社交网络(EBSNs)为用户提供了方便的组织、参加和分享社交活动的平台。该文面向EBSNs活动推荐问题,提出了包含活动(Event)、主办方(Sponsor)和用户(User)的ESU图模型,深入揭示了EBSNs的实体及其社交关系。因为用户参加活动受多个因素影响,我们提出了基于ESU图的活动推荐多因素决策模型,包括社交影响力、活动内容、活动地点及活动时间。根据ESU图特点,提出了基于双向重启随机游走算法BD-RWR的实体重要度计算方法。选取真实的EBSNs平台—豆瓣同城验证所提方法的有效性。实验结果表明,该文提出的ESU图模型及融合了多因素的活动推荐模型,与已有最新方法相比,有效地提升了用户参加活动的推荐效果。 相似文献
99.
将强跟踪思想引入容积卡尔曼滤波(cubature Kalman filter,CKF),建立强跟踪CKF能有效克服CKF在模型不确定、状态突变等情况下,滤波性能下降的问题。通过分析现有多渐消因子计算方法,发现它们均只利用了协方差矩阵的对角线元素,并没有考虑各个状态之间的相关性,不能充分发挥多渐消因子的优势。为此,本文提出渐消因子矩阵,基于正交原理推导渐消因子矩阵的求解方法,提出多渐消因子强跟踪CKF算法。多渐消因子强跟踪CKF算法突破了传统多渐消因子为向量的限制,也不再要求渐消因子取值要大于1。仿真验证了算法具有更好的滤波精度何鲁棒性,能更好的满足工程应用的要求。 相似文献
100.
The paper discusses a niche area problem — the design of reduced-order multiple observers which can achieve the finite-time state reconstruction for Takagi–Sugeno multiple models with unknown inputs. The new reduced-order multiple observer obtained in this paper is only the second ever designed, the author of this paper continuing his work started one year ago with the introduction of the reduced-order multiple observer concept. The obtaining of the new reduced-order multiple observer is achieved by combining two classical reduced-order observers for linear time-invariant multivariable systems with unknown inputs and a full-order multiple observer for Takagi–Sugeno systems. The main innovative idea behind the design of the reduced-order multiple observer for Takagi–Sugeno systems described by the multiple models is the split of the multiple model into two subsystems: an unknown-input-free subsystem and an unknown-input-depending subsystem. The unknown-input-free subsystem is brought to the form of a standard multiple model and, in this situation, any algorithm to design full-order multiple observers can be used in the design of reduced-order multiple observers. The steps of the design procedure have been summarized and software implemented; then, the validation of the suggested algorithm has been done for two concrete cases associated to the motion of an aircraft during its landing 相似文献