A Novel Dynamic Adjusting Algorithm for Load Balancing and Handover Co-Optimization in LTE SON

With the development of mobile internet and multi-media service, advanced techniques need to be applied in wireless network to improve user experience. Long term evolution (LTE) systems, which can offer up to 100Mbps downlink date rates, have been deployed in USA and Korea. However, because plenty of complex physical layer algorithms are utilized, network planning and optimization become heavy burdens for LTE network operators. Self-organizing network (SON) is a promising method to overcome this problem by automatically selecting and adjusting key parameters in LTE systems. In this paper, we present a dynamic adjusting algorithm to improve both handover and load balancing performance by introducing a weighted co-satisfaction factor (CSF). Analysis and system level simulation are conducted to exhibit the performance improvement of the proposed scheme. Results show that the proposed method outperforms the conventional solutions in terms of the network handover success ratio and load balancing gains significantly.     

Interactions between tea polyphenols and nutrients in food

Tea polyphenols (TPs) are important secondary metabolites in tea and are active in the food and drug industry because of their rich biological activities. In diet and food production, TPs are often in contact with other food nutrients, affecting their respective physicochemical properties and functional activity. Therefore, the interaction between TPs and food nutrients is a very important topic. In this review, we describe the interactions between TPs and food nutrients such as proteins, polysaccharides, and lipids, highlight the forms of their interactions, and discuss the changes in structure, function, and activity resulting from their interactions.     

Wake suppression behind two slightly non-coplanar cylinders

We here have found when the two parallel cylinders are arranged slightly non-coplanar, the vortex shedding could be significantly suppressed above Reynolds number of 6000. This finding is unlike the common understanding that the Karman vortex formation behind the structure can be manipulated when a structure located within the inherently unstable near wake of another structure. It is particularly important for flow control, since the flow-induced vibration of two parallel cylinders can be suppressed effectively with only slightly non-coplanar arrangement.     

A facile strategy to integrate robust porous aluminum foil into microfluidic chip for sorting particles

High efficiency integration of functional microdevices into microchips is crucial for broad microfluidic applications. Here, a device-insertion and pressure sealing method was proposed to integrate robust porous aluminum foil into a microchannel for microchip functionalization which demonstrate the advantage of high efficient foil microfabrication and facile integration into the microfluidic chip. The porous aluminum foil with large area (10 × 10 mm²) was realized by one-step femtosecond laser perforating technique within few minutes and its pores size could be precisely controlled from 3 μm to millimeter scale by adjusting the laser pulse energy and pulse number. To verify the versatility and flexibility of this method, two kinds of different microchips were designed and fabricated. The vertical-sieve 3D microfluidic chip can separate silicon dioxide (SiO₂) microspheres of two different sizes (20 and 5 μm), whereas the complex stacking multilayered structures (sandwich-like) microfluidic chip can be used to sort three different kinds of SiO₂ particles (20, 10 and 5 μm) with ultrahigh separation efficiency of more than 92%. Furthermore, these robust filters can be reused via cleaning by backflow (mild clogging) or disassembling (heavy clogging).     

Scalable service differentiation using purely end-to-end mechanisms: features and limitations

We investigate schemes for achieving service differentiation via weighted end-to-end congestion control mechanisms within the framework of the additive-increase-multiplicative-decrease (AIMD) principle, and study their performance as instantiations of the TCP protocol.Our first approach considers a class of weighted AIMD algorithms. This approach does not scale well in practice because it leads to excessive loss for flows with large weights, thereby causing early timeouts and a reduction in throughput.Our second approach considers a class of loss adaptive weighted AIMD algorithms. This approach scales by an order of magnitude compared to the previous approach, but is more susceptible to short-term unfairness and is sensitive to the accuracy of loss estimates.We conclude that adapting the congestion control parameters to the loss characteristics is critical to scalable service differentiation; on the other hand, estimating loss characteristics using purely end-to-end mechanisms is an inherently difficult problem.     

Integration of displacement sensor into bulk PZT thick film actuator for MEMS deformable mirror

Bulk PZT thick film actuator integrated with displacement sensor, the so-called self-sensing actuator, is presented in this paper. The PZT film is used as not only an actuating layer but also a displacement sensor, which is achieved by dividing the electrode on the top surface of the PZT film into two parts: central top electrode for actuating and outer annular sensor electrode for piezoelectric displacement detection. When the actuator moves, the piezoelectric charge is induced in the outer annular PZT due to the piezoelectric effect. The total amount of accumulated charge is proportional to the stress acting on the PZT, which is in turn proportional to the actuator displacement. By collecting the piezoelectric charge, the actuator displacement can be detected. A theoretical model is proposed to determine the structure parameters of the sensor and predict the sensor sensitivity. Experiments were performed on the micro-fabricated sensor integrated PZT thick film actuator, and the measured piezoelectric charge is close to the theoretical predictions. The integrated piezoelectric sensor has a displacement sensitivity of approximately 4 pC/nm. In addition, the integration of displacement sensor into the actuator needs no additional fabrication process and has no influence on the actuator performances.     

Vortex-induced vibration control by micro actuator

The control of vortex-induced vibration of two side-by-side circular cylinders in a cross flow is carried out experimentally. One cylinder is elastically supported and the other is fix-supported at both ends. The two cylinders vibrate under the action of the unsteady flow-induced forces. A micro actuator is embedded on the surface of each cylinder to perturb the boundary layer. The spacing ratio is set at 1.2. The measurement shows that the structural vibration can be suppressed significantly when the reduced excitation frequency is around 2.655.     

基于自注意力机制的点云分类分割

3D点云由于其无序性以及缺少拓扑信息使得点云的分类与分割仍具有挑战性.针对上述问题,我们设计了一种基于自注意力机制的3D点云分类算法,可学习点云的特征信息,用于目标分类与分割.首先,设计适用于点云的自注意力模块,用于点云的特征提取.通过构建领域图来加强输入嵌入,使用自注意力机制进行局部特征的提取与聚合.最后,通过多层感知机以及解码器-编码器的方式将局部特征进行结合,实现3D点云的分类与分割.该方法考虑了输入嵌入时单个点在点云中的局部语境信息,构建局部长距离下的网络结构,最终得到的结果更具区分度.在ShapeNetPart、RoofN3D等数据集上的实验证实所提方法的分类与分割性能较优.     

竹叶多糖的提取纯化、结构解析及生物活性研究进展

竹叶富含多种生物活性成分,如多糖、多酚及黄酮类物质等。竹叶多糖作为竹叶提取物中的重要生物活性成分,具有抗氧化、免疫调节、抗肿瘤和降血脂等功效。近年来,为提高纯度、提高产率和保留生物活性,竹叶多糖的提取和纯化技术有了许多创新。其次,对竹叶多糖的复杂结构,结构与生物活性的关系及生物活性的作用机制等方面的研究也逐渐加深。本文综述了竹叶多糖在提取纯化、结构解析和生物活性等方面的研究进展,并展望了未来的研究方向,旨在为深入研究竹叶多糖提供一个全面的认识,推动竹叶多糖的进一步开发和利用,为后续开展对竹叶多糖进行结构修饰等相关研究提供新思路,以增强生物活性,并为其在食品、医药和工业领域的应用提供科学依据,进而推动竹叶资源的充分利用。