Dynamic Rate and Power Allocation in Wireless Ad Hoc Networks with Elastic and Inelastic Traffic

In this paper, we focus on the problem of dynamic rate and power allocation in wireless ad hoc networks with slow-fading channels, where a mixture of elastic and inelastic traffic is supported. A stochastic optimization problem incorporating the quality of service requirements of the two types of traffic is formulated, which aims to maximize the network performance by allocating the power for each link and controlling the service rates of all flows in the network. Since the utility functions of inelastic flows may be non-concave, which are difficult to be readily transformed to be concave, the proposed original problem is non-convex. However, despite the existing difficulty, a dynamic rate and power allocation algorithm (named DRPAA), is proposed to solve the original optimization problem. In DRPAA, both the stochastic duality theory and the particle swarm optimization approach are used, and this dynamic algorithm provides a good approximation to the optimal solution when the variation of the channel condition of each link gets larger. By using DRPAA, flow rates and link powers are dynamically allocated in each network state without the need for the distribution of the network states. Simulation results show that DRPAA has a good convergence speed and can efficiently utilize network resources to improve the network performance.     

城市绿线控制规划编制探讨——以龙岩市中心城区绿线控制规划为例

结合龙岩市中心城区绿线控制规划实践,借鉴城市规划设计的理念和手段,从城市绿地系统规划、控制性详细规划的层面探讨城市绿线控制规划编制的思路、方法并剖析编制误区。     

山东省栖霞台前地区控矿构造与找矿预测

胶东金矿集区是中国最大的金矿集区,具有良好的金成矿地质背景。胶东金矿集区内金矿床具有新太古界地层、中生代侵入岩及断裂共同耦合控矿特征。台前地区位于胶东金矿集区内,具有良好的成矿条件,已发现金矿床(点)受断裂控制明显。通过解析台前地区控矿断裂的几何特征、力学性质、期次划分,并与招平断裂进行对比,结合典型矿床构造控矿特征及矿体赋存规律,对成矿规律进行了总结,统计了成矿要素,指出马疃地区、马家疃地区具有良好的找矿潜力。     

Microfluidic Templated Multicompartment Microgels for 3D Encapsulation and Pairing of Single Cells

Controlled encapsulation and pairing of single cells within a confined 3D matrix can enable the replication of the highly ordered cellular structure of human tissues. Microgels with independently controlled compartments that can encapsulate cells within separately confined hydrogel matrices would provide precise control over the route of pairing single cells. Here, a one‐step microfluidic method is presented to generate monodisperse multicompartment microgels that can be used as a 3D matrix to pair single cells in a highly biocompatible manner. A method is presented to induce microgels formation on chip, followed by direct extraction of the microgels from oil phase, thereby avoiding prolonged exposure of the microgels to the oil. It is further demonstrated that by entrapping stem cells with niche cells within separate but adjacent compartments of the microgels, it can create complex stem cell niche microenvironments in a controlled manner, which can serve as a useful tool for the study of cell–cell interactions. This microfluidic technique represents a significant step toward high‐throughput single cells encapsulation and pairing for the study of intercellular communications at single cell level, which is of significant importance for cell biology, stem cell therapy, and tissue engineering.     

异步化同步发电机无转速传感器控制

论述了异步化同步发电机有功功率和无功功率解耦控制原理,讨论了定子磁场的定位和转子位置的确定方法,以转子电流作为反馈量,构造了定子磁链观测器.借助于李亚普诺夫稳定理论,给出转子转速观测的递推模型.研制了DSP转子励磁控制装置,进行了异步化同步发电机无转速传感器的励磁控制试验研究.试验结果表明,转速观测器可以有效地确定转子转速,从而实现发电机的无转速传感器控制.     

一个全数字化交流永磁伺服系统

介绍了开发的全数字交流伺服系统的组成、基本原理及软、硬件结构。通过与模拟交流伺服系统的比较，说明了全数字交流伺服系统可编程能力强、系统稳定性好、系统性能提高等特点。     

Structure and surface properties of a novel bulk-matte waterborne polyurethane coating composite

This paper reports on a novel self-matte or bulk-matte waterborne polyurethane coating composite with inherently extremely low gloss. The coating composite was comprised of a siloxane-containing waterborne polyurethane (SPU) resin and a crosslinked waterborne polyurethane (CPU) resin. The CPU resin was mainly responsible for fabricating the micro-rough surface of the film, which was achieved by a crosslinking reaction between the waterborne polyurethane and bisphenol A-type epoxy E-44 resin. The SPU resin was used to improve the comprehensive properties of the film, which was ascribed to the addition of silane coupling agent KH792. Compared with traditional matte coatings, this coating composite made it possible to avoid high loadings of matting agent and to arrive at highly flexible low-gloss finishes. Gloss levels of as low as a few tenths of a percent, even at high incidence angles, have been achieved with zero loading of extraneous dulling agent. The chemical structures of the SPU and CPU resins were characterized by FTIR-ATR and NMR spectra. The micro-rough topographies and surface rough degrees of the SPU, CPU and their 50%/50% composite films were measured by SEM and MSP, respectively. The particle sizes and particle morphologies of the SPU and CPU resins were imaged by TEM. Finally, the comprehensive properties of the SPU, CPU and their 50%/50% composite resins were evaluated, including the water contact angle, film transparency, tensile strength and storage stability.     

脂肪族聚酯熔点的预估——对D．W．Vankrevelen经验公式的修正

对D．W．Vankrevelen经验公式进行了修正,并对脂肪族聚酯的熔点进行了计算。结果表明,修正后的公式比原公式准确性星著提高,可对脂肪族聚酯熔点进行预估。     

LP-MOCVD生长InGaAlP外延层In组分控制的动力学分析

本文分析了低压转盘ＭＯＣＶＤ生长室中气流的流动特征,首次提出了在高温（７００℃左右）下生长ＩｎＧａＡｌＰ外延层时,抑制Ｉｎ组分脱吸附的“动压力模型”．解释了托盘转速和生长压力等生长参数对Ｉｎ组分控制的影响．     

菌种配比对发酵猪耳西式火腿品质的影响

以猪耳为原料,经乳酸菌发酵加工西式火腿。借助国际通用的物性测定仪,通过单因子试验探讨了发酵猪耳西式火腿在加工过程中乳酸菌菌种配比对该产品的物性(包括硬度、弹性、咀嚼性、凝聚性、黏着性和脆性)、出品率、pH值以及感官品质的影响。结果表明:①以乳酸菌接种量15%,发酵24h计,当菌种-A和菌种-B按1∶1的比例组合时,产品可获得较理想的pH值和感官评分。②菌种配比对产品的物性有显著的影响,但无明显的规律,各物性之间也无明显的相关性。③发酵菌种配比对产品出品率没有显著的影响。