Max-Min Fair RIS-Aided Rate-Splitting Multiple Access for Multigroup Multicast Communications

Rate-splitting multiple access(RSMA)can cope with a wide range of propagation conditions in multigroup multicast communications through rate splitting optimization.To breakthrough the grouprate limited bottleneck,reconfigurable intelligent surface(RIS)technique can be introduced to assist wireless communications through enhancing the channel quality.In RIS-aided RSMA multigroup multicasting,how to provide fair and high-quality multiuser service under power and spectrum constraints is essential.In this paper,we propose a max-min fair RIS-aided rate-splitting multiple access(MMF-RISRSMA)scheme for multigroup multicast communications,where the rate fairness is obtained by maximizing the minimum group-rate.In doing so,we jointly optimize the beamformers,the rate splitting vector at the transmitter,as well as the phase shifts at RIS.To solve it,we divide the original optimization problem into two subproblems and alternately optimize the variables.The beamforming and rate splitting optimization subproblem is solved by using the successive convex approximation technique.The phase shift optimization subproblem is solved through the penalty function method to achieve a rank-one locally optimal solution.Simulations demonstrate that the proposed MMF-RIS-RSMA scheme can obtain significant performance gain in terms of the minimum group-rate.

Mobile-Service Based Max-Min Fairness Resource Scheduling for Heterogeneous Vehicular Networks

This paper investigates the resource scheduling for heterogeneous vehicular networks, where some moving vehicles are selected and scheduled as helping relays to assist information transmission between the roadside infrastructure and other moving vehicles. For such a system, we propose a mobile-service based max-min fairness resource scheduling scheme, where service amount which is more suitable for high mobility scenarios is adopted to characterize the information transmission capacity of the links and the max-min criteria is adopted to meet the fairness requirement of the moving vehicles. Simulation results demonstrate the effectiveness of our proposed scheme. It is shown that our proposed scheme archives higher throughput and better fairness compared with random scheduling scheme and non-relaying scheme.

Fairness-Oriented Hybrid Precoding for Massive MIMO Maritime Downlink Systems with Large-Scale CSIT

Different from conventional cellular networks, a maritime communication base station(BS) has to cover a much wider area due to the limitation of available BS sites. Accordingly the performance of users far away from the BS is poor in general. This renders the fairness among users a challenging issue for maritime communications. In this paper, we consider a practical massive MIMO maritime BS with hybrid digital and analog precoding. Only the large-scale channel state information at the transmitter(CSIT) is considered so as to reduce the implementation complexity and overhead of the system. On this basis, we address the problem of fairness-oriented precoding design. A max-min optimization problem is formulated and solved in an iterative way. Simulation results demonstrate that the proposed scheme performs much better than conventional hybrid precoding algorithms in terms of minimum achievable rate of all the users, for the typical three-ray maritime channel model.

DMMF: Dominant and Max-Min Fair Allocation in Satellite Networks

Resource allocation is crucial for satellite networks. In this paper, we propose a multi-resource fair allocation scheme, namely Dominant and Max-min Fair(DMMF), to efficiently and fairly allocate resources. It consists of two allocation stages, dominant resource fair(DRF) allocation stage and max-min fairness(MMF) allocation stage. The proposed DMMF scheme exhibits desirable properties, including share incentive, strategy proofness, envy freeness and Pareto optimality. Meanwhile, DMMF can improve the allocation efficiency and reach 100% allocation efficiency.

A NEW ABR CONGESTION CONTROL ALGORITHM ACHIEVING FAIRNESS UNDER SEVERAL CRITERIA

All ABR congestion control algorithms reported are designed to achieve max-min fairness. In this paper, a new algorithm named dynamic bandwidth allocation algorithm is presented. Under the same framework, the algorithm can achieve fairness under several given criteria. Simulation result shows that the new algorithm works well under various network configurations, various traffic classes, and scale well to LANs or WANs.

铺层对直升机整流罩失效的影响研究

直升机整流罩具有维形整流、包覆天线等作用。在结构设计时,针对实际使用工况,对结构失效模式进行预测,以指导结构设计,提高产品安全性。考虑层合壳的整流罩模型,各层之间纤维铺设角度不同,采用Tsai-Wu失效准则对各层的失效情况进行预测。研究结果表明,铺层角度垂直于载荷方向的纤维层最容易失效。

RIS-Aided Constant-Envelope Beamforming for Multiuser Wireless Power Transfer:A Max-Min Approach

As a revolutionary hardware technology that can reconfigure the propagation environment,reconfigurable intelligent surfaces(RISs)have been regarded as a promising solution to enhance wireless networks.In this paper,we consider a multiuser multiple-input single-output(MISO)wireless power transfer(WPT)system,which is assisted by several RISs.In order to improve energy efficiency and reduce hardware cost,we consider that the energy transmitter(ET)in the WPT system is equipped with a constant-envelope analog beamformer,instead of a digital beamformer.Focusing on user fairness,we study a minimum received power maximization problem by jointly optimizing the ET beamforming and the RIS phase shifts,subject to the constant-envelope constraints.We iteratively solve this non-convex maxmin problem by leveraging both the successive convex approximation(SCA)method and the alternating direction method of multipliers(ADMM)algorithm.Numerical results demonstrate the effectiveness of the proposed algorithm and show attractive performance gain brought by RISs.

《民法典》第1186条(公平责任规则)评注

《民法典》第1186条对公平责任规则作出实质性修改,强调法官判定无过错的当事人分担损失,应当严格遵循法律的特别规定。从《民法通则》到《民法典》,公平责任规则在我国已经存续三十多年,具有存在的必要性和坚实的法理依据。通过对《民法典》第1186条进行体系解释和文义解释,可以得出公平责任规则是分担损失的一般规则,而不是归责原则。关于“依照法律的规定”的指向范围,应当仅包括《民法典》第1190条无过错的暂时丧失心智者的补偿责任和第1254条可能加害的建筑物使用人的补偿责任两类,其他类型的补偿责任均不在公平责任规则的适用范畴之内。

电力市场非线性费用函数分摊公平性准则

非线性函数值分摊理论中改变路径函数后,函数值的分摊将发生变化,因而自变量的分摊值可表达为路径函数的泛函。如何选择非线性函数值分摊路径与评判分摊结果的合理性是关键。为此对电力系统非线性费用函数值分摊理论中的积分区间划分原则进行了研究,根据泛函极值理论提出了电力系统非线性费用函数值分摊的合理性评判准则与公平性条件。网损交互项分摊的数值计算表明:自变量按同比例的变化路径能满足基于泛函极值理论的合理性评判准则,按等比例步长划分积分区间是所有满足合理性准则中的最简单的一种。

Energy efficient resource allocation for D2D multicast communications

The resource allocation for device-to-device(D2D)multicast communications is investigated.To achieve fair energy efficiency(EE)among different multicast groups,the max-min fairness criterion is used as the optimization criterion and the EE of D2D multicast groups are taken as the optimization objective function.The aim is to maximize the minimum EE for different D2D multicast groups under the constraints of the maximum transmit power and minimum transmit rate,which is modeled as a non-convex and mixed-integer fractional programming problem.Here,suboptimal resource allocation algorithms are proposed to solve this problem.First,channel assignment scheme is performed to assign channel to D2D multicast groups.Second,for a given channel assignment,iterative power allocation schemes with and without loss of cellular users’rate are completed,respectively.Simulation results corroborate the convergence performance of the proposed algorithms.In addition,compared with the traditional throughput maximization algorithm,the proposed algorithms can improve the energy efficiency of the system and the fairness achieved among different multicast groups.

我国著作权合理使用判断标准的反思与重构

因素主义和规则主义是世界各国著作权合理使用判断标准的两种基本模式,各有利弊。我国立法目前采用完全的规则主义模式,在实践中造成了判断标准的僵化,无法完全适应现实生活的需要。以利益平衡为原则,以作品的使用目的、被使用作品的性质、使用作品的程度以及对被使用作品的市场影响为要素并辅之以具体规则的"原则+要素+规则"的模式应当成为我国著作权合理使用判断标准的重构方向。

带宽分配中效率与公平性问题研究

本文提出了新的衡量网络带宽分配算法的公平性和效率的定义。基于这个定义对不同的网络带宽公平性分配算法之间的公平性和效率进行了比较。带宽分配问题可以看作是求解一个最大化效用函数的问题,给出了一个新的效用函数,对它在具体网络中的分配和其他公平性分配算法进行比较,建立了它们之间的一种对应关系。

金融资产以公允价值计量会加剧市场同涨同跌吗?——论公允价值准则与市场同步性的关系

本文基于美国金融危机爆发和中国引入公允价值准则的大背景,试图探究公允价值准则与市场同步性的关系,即回答金融资产以公允价值计量是否会加剧市场同涨同跌现象这一问题。在顺周期效应、功能锁定假说、契约成本假说、信息质量假说、噪音投资者心理倾向论等理论基础上,文章分别从牛市、熊市角度分析了公允价值准则影响市场同步性的内在机理,并对2007、2008年的市场交易状况做了均值T检验和WILCOXON检验。结果发现:牛市中公允价值准则的采用会提高市场同步性(即推动市场整体上涨),而熊市中两者关系不显著。该结论除了可用上述理论作部分解释外,也与中国政府的宏观调控政策有关。

基于跨层公平性准则的自适应无线资源分配方法

该文提出了一种新的公平性准则,它既适用于实时业务又适用于非实时业务,是一种对物理层和MAC层联合优化的跨层公平性准则。基于该准则提出了一种新的跨层自适应资源分配方案。仿真结果显示,该方案不仅可以较好地满足用户提出的QoS要求,而且可以保证用户间服务质量满意度的公平性。

一种新的适用于多种公平准则的ABR流控算法的设计和研究

现有的各种ABR拥塞控制算法都只能实现最大最小准则下的公平性。本文提出了一种称为“动态带宽分配”(DBA)的控制算法,在该算法框架内可以方便地实现ATM论坛定义的任一准则下的公平性。仿真实验结果表明,新算法性能良好。

论推动自主招生进入常态化

自主招生是招生改革的大方向,而不是权宜之计。推进自主招生关键在于明确自主招生的定位、内涵、实施条件。它不是强势学校掐尖,而是使每所学校招到适合自己教育教学的学生,同时使尽可能多的学生进入适合自己天性、学习能力和职业规划的学校,能更为有效地通过大学学习实现人生幸福。为保障这一目标的实现,必须创设公开透明的环境,排除行政权力对招生过程的干扰;建立专业的招生团队,遵循专业的招生程序和规则,用刚性实证评价结果做依据,执行专业标准以实现实质公平,在条件成熟时一点一滴逐步推进,积极扩大自主招生面。

学术领域马太效应及其评价调控准则漫谈

伴随着学术评价的发展,学术领域马太效应有愈演愈烈之势。马太效应带来的有悖学术发展的问题也日益凸显,因此遭到学术界乃至社会舆论诟病。客观认识学术领域马太效应及其作用机制,理清学术领域马太效应与学术评价的关系,坚持学术评价真理标准与公平原则等,是发挥学术领域马太效应正效应,避免其负效应的前提。学术发展离不开学术管理,学术管理又不能缺少学术评价,学术评价不可避免地产生马太效应,就是说,学术领域马太效应是学术发展过程客观存在的现象,对此如何利用学术评价来调控是需要研究的学术管理问题。

论我国上市公司少数股东保护制度的完善

我国上市公司少数股东保护制度经历了一个由简至繁、由疏到密的不断充实的发展历程,一系列的相关立法行为对完善我国上市公司治理结构具有非常重要的意义。目前,我国上市公司少数股东保护制度的构建虽已取得了长足进展,但还存在许多尚待完备之处。文中将通过考察我国上市公司少数股东保护制度形成的沿革,对我国上市公司少数股东保护制度的立法思路和方向进行归纳梳理,并就我国上市公司少数股东保护的相关制度——股东表决权排除制度、控股股东损害赔偿责任制度、控股股东及从属公司经营者责任追究制度、监事会制度等中存在的问题进行分析探讨,提出相应的完善对策。

试论商标权合理使用制度的建构

任何权利都是有限制的,商标权也不例外,它虽然具有较强的专有性,但并不是完全不受限制的权利。在实践中,商标权人往往将自己的注册商标的专用权理解为绝对的私权而阻碍公众对公有领域知识的合理使用。随着市场经济的发展和商标法实践的深入,因商标权合理使用问题引发的各种冲突越来越激烈,对商标权进行限制已经成为目前各国商标立法的立法趋势,并出现在国际公约中。因此在我国商标立法中明确界定商标权的权利边界和合理使用的标准是相当迫切和重要的。

按最小速率分配的ABR控制算法公平性的研究

现有的各种ABR拥塞控制算法都只能实现最大最小准则下的公平分配。文中提出了一种称为“既得利益”相等的设计思想。依据这一思想改造现有算法 ,原则上可以在原算法框架内实现任一准则下的公平性。作为例子 ,我们改造了ERICA算法 ,使得新算法能达到ATM论坛定义的按MCR成比例分配带宽准则下的公平性。仿真实验结果表明 ,新算法性能良好。