Design of cost allocation rule for joint replenishment with controllable lead time

To encourage retailers to form cooperative alliances to jointly replenish inventory,considering that the supplier provides a flexible lead time and quantity discount to retailers,a model of average total cost per unit time of periodic joint replenishment is constructed,and an approximate algorithm,which can satisfy the requirement of any given precision,is given.The cost allocation rule in the core of the joint replenishment game is designed based on the cooperative game theory.The numerical experiment results show that the proposed algorithm can quickly solve the joint replenishment problem when the item number is not greater than 640.The retailer's cost saving rate is always greater than 0,and it increases with the increase in quantity discount and fixed cost after adopting the given cost allocation rule.With the increase in the safety stock level,the retailer's cost saving rate increases first and then decreases;and the retailer's cost saving rate increases with the increase in the size of the alliance,but it decreases as the number of product category increases.The proposed cost allocation rule can reduce the retailer's cost up to 20%,which is conducive to forming a cooperative coalition.

Polynomial Time Method for Solving Nash Equilibria of Zero-Sum Games

There are a few studies that focus on solution methods for finding a Nash equilibrium of zero-sum games. We discuss the use of Karmarkar’s interior point method to solve the Nash equilibrium problems of a zero-sum game, and prove that it is theoretically a polynomial time algorithm. We implement the Karmarkar method, and a preliminary computational result shows that it performs well for zero-sum games. We also mention an affine scaling method that would help us compute Nash equilibria of general zero-sum games effectively.

H_∞ control for stochastic systems with time-delay

The H∞-control problem of stochastic systems with time-delay is considered. The sufficient conditions are obtained, under which there are always state-feedback control and dynamic output-feedback control so that the resulting closed-loop system is internaly stable and L2 input-output stable in the sense of expectation. Furthermore, the explicit formulas of both kinds of controls are derived. An example is included to illustrate the correctness of theoretic results.

Influences of Network Delay on Quality of Experience for Soft Objects in Networked Real-Time Game with Haptic Sense

In this paper, we investigate the influences of network delay on QoE (Quality of Experience) such as the operability of haptic interface device and the fairness between players for soft objects in a networked real-time game subjectively and objectively. We handle a networked balloon bursting game in which two players burst balloons (i.e., soft objects) in a 3D virtual space by using haptic interface devices, and the players compete for the number of burst balloons. As a result, we find that the operability depends on the network delay from the local terminal to the other terminal, and the fairness is mainly dependent on the difference in network delay between the players’ terminals. We confirm that there exists a trade-off relationship between the operability and the fairness. We also see that the contribution of the fairness is larger than that of the operability to the comprehensive quality (i.e., the weighted sum of the operability and fairness). Assessment results further show that the output timing of terminals should be adjusted to the terminal which has the latest output timing to maintain the fairness when the difference in network delay between the terminals is large. In this way, the comprehensive quality at each terminal can be maintained as high as possible.

关于Banach空间值L^1S-games与随机变量阵列完全收敛性的几个注记

设B是一实可分的Banach空间,具有Radon-Nikodyn性质(RNP).{Xn,n≥1}是L1B中的序列,其子序列{Xs,s∈S}是一L1极限鞅.证明了{Xn,n≥1}是L1S-game的充分必要条件是{Xn,n≥1}在条件liminfnE‖XSn‖<∞下或条件∫{τ<∞}‖XSτ‖dP<∞,τ∈下依概率收敛,其中是由{Fn,n∈N}的停时组成的集合,Sn=inf{s∈S:n≤s},n∈N.这个结论推广与改进了Luu的相关结果.而行独立的B值随机变量阵列完全收敛性的两个结果则改进与推广了T.C.Hu等人的相应结果.

Zero-Sum Continuous-Time Markov Games with One-Side Stopping

The paper is concerned with a variant of the continuous-time finite state Markov game of control and stopping where both players can affect transition rates,while only one player can choose a stopping time.The dynamic programming principle reduces this problem to a system of ODEs with unilateral constraints.This system plays the role of the Bellman equation.We show that its solution provides the optimal strategies of the players.Additionally,the existence and uniqueness theorem for the deduced system of ODEs with unilateral constraints is derived.

Twelve weeks of dance exergaming in overweight and obese adolescent girls:Transfer effects on physical activity,screen time,and self-efficacy

Background: Given the low levels of physical activity(PA) among adolescent girls in the US, there is a need to identify tools to motivate increased PA. Although there is limited evidence that adolescents transfer PA from one context to another, exergames(i.e., video games that require gross motor activity) may act as a gateway to promote overall PA outside game play. The purpose of this study was to examine potential transfer effects(i.e., influences on external behaviors and psychological constructs) of a 12-week exergaming intervention on adolescent girls' PA, screen time,and self-efficacy toward PA, as well as the intrinsic motivation of exergaming.Methods: Participants were 37 girls aged 14–18 years(65% African American, 35% white) who were overweight or obese(body mass index ≥ 85 th percentile) and were recruited from the community via school, physicians, news media, and social media websites. Adolescents were randomly assigned to a 12-week group exergaming intervention(thirty-six 60 min sessions of group-based dance exergaming in a research laboratory using Kinect for Xbox360(Microsoft Corporation, Redmond, WA, USA)) or to a no-treatment control group. Outcome variables included objectively measured PA(total) and self-reported leisure-time PA(discretionary time only) 1 week before vs. 1 week after the intervention; selected type and intensity of PA when placed in a gym setting for 30 min("cardio free choice"); screen time; self-efficacy toward PA; and intrinsic motivation toward exergaming.Results: Attendance at the exergaming sessions was high(80%). Compared with the control group, the intervention group self-reported an increase in PA(p = 0.035) and fewer hours watching television or videos(p = 0.01) after the intervention, but there were no significant differences in sedentary, light, moderate, or vigorous PA measured by accelerometry. The intervention group significantly improved self-efficacy toward PA(p = 0.028). The intervention group highly rated intrinsic motivation toward exergaming.Conclusion: Exergaming for 12 weeks was associated with positive impacts on adolescent girls' self-reported PA, television viewing, self-efficacy,and intrinsic motivation. Future research is warranted to leverage exergames as an enjoyable, motivating, and effective PA tool.

Optimizing Polynomial-Time Solutions to a Network Weighted Vertex Cover Game

Weighted vertex cover(WVC)is one of the most important combinatorial optimization problems.In this paper,we provide a new game optimization to achieve efficiency and time of solutions for the WVC problem of weighted networks.We first model the WVC problem as a general game on weighted networks.Under the framework of a game,we newly define several cover states to describe the WVC problem.Moreover,we reveal the relationship among these cover states of the weighted network and the strict Nash equilibriums(SNEs)of the game.Then,we propose a game-based asynchronous algorithm(GAA),which can theoretically guarantee that all cover states of vertices converging in an SNE with polynomial time.Subsequently,we improve the GAA by adding 2-hop and 3-hop adjustment mechanisms,termed the improved game-based asynchronous algorithm(IGAA),in which we prove that it can obtain a better solution to the WVC problem than using a the GAA.Finally,numerical simulations demonstrate that the proposed IGAA can obtain a better approximate solution in promising computation time compared with the existing representative algorithms.

Hybrid Estimation of State and Input for Linear Discrete Time-varying Systems： A Game Theory Approach

为线性分离变化时间的系统的 H 混合评价问题在这份报纸被调查，在估计的信号是状态和输入的线性联合的地方。设计目的从骚乱要求最坏的精力获得到是的评价错误不到规定水平。混合评价问题的最佳的答案是僵绳点一二播放器零和微分游戏。根据微分比赛途径，为混合评价问题的必要、足够的可解决的条件以一个 Riccati 微分方程的答案被提供。而且，如果可解决的条件满足，一个可能的评估者被建议。评估者被印射矩阵的一个获得矩阵和产量描绘，在后者反映在未知输入和输出评价错误之间的内部关系的地方。最后，一个数字例子被提供说明建议途径。

Hybrid Estimation of State and Input for Linear Continuous Time-varying Systems:A Game Theory Approach

The H∞ hybrid estimation problem for linear continuous time-varying systems is in-vestigated in this paper, where estimated signals are linear combination of state and input. Designobjective requires the worst-case energy gain from disturbance to estimation error be less than a pre-scribed level. Optimal solution of the hybrid estimation problem is the saddle point of a two-playerzero sum di?erential game. Based on the di?erential game approach, necessary and su?cient solvableconditions for the hybrid estimation problem are provided in terms of solutions to a Riccati di?e-rential equation. Moreover, one possible estimator is proposed if the solvable conditions are satisfied.The estimator is characterized by a gain matrix and an output mapping matrix that re?ects theinternal relations between the unknown input and output estimation error. Both state and unknowninputs estimation are realized by the proposed estimator. Thus, the results in this paper are alsocapable of dealing with fault diagnosis problems of linear time-varying systems. At last, a numericalexample is provided to illustrate the proposed approach.

Pass Appearance Time and Pass Attempts by Teams Qualifying for the Second Stage of FIFA World Cup 2014 in Brazil

This study aimed to clarify the difference between the not qualified teams and the qualified teams to 2nd stage in the Pass Appearance Time and passes attempted at all group stage games of World Cup 2014 and compared with World cup 2010. Results indicated changes in passing in modem football tactics. Actual playing time is represented as Net Playtime in this study. Pass Appearance Time is calculated by Net Playtime divided by passes Attempted. Pass Appearance Time of each team for the all Group stage games was calculated and compared with World cup 2010. No difference was revealed in the 2014 data between teams that did and did not qualify, though the 2010 data revealed differences. World cup 2010 data suggested that increasing passes attempts and lessening Pass Appearance Time were effective in qualifying for the 2rid stage. World cup 2014 data, however, suggested that diversity of tactics was important.

预售模式下电商平台订货时间与定金决策研究

预售模式延长了产品整体销售周期,这为电商平台的产品订货时间决策带来了新问题。为研究对比提前与延后两种订货时间策略影响下的产品定金、产品价格与电商平台利润,建立两阶段主从博弈模型,分析定金敏感度、尾款敏感度和制造成本对订货时间选择与产品定金决策的影响。结果表明:在延后订货模式中,定金、尾款敏感度对产品订货价格影响相反;在提前订货模式中,只有定金敏感度影响产品订货价格。电商平台预售券/定金策略受消费者尾款敏感度影响。

“赶工游戏”对外卖骑手不安全驾驶的影响:基于压力认知评价的视角

为有效防范外卖骑手不安全驾驶行为,减少由外卖骑手引发的交通安全事故,基于外卖平台“赶工游戏”的工作机制,结合压力认知评价理论,从安全态度和示范性规范角度,构建时间压力和竞争氛围感知对外卖骑手不安全驾驶行为影响的理论模型;向全国各地的外卖骑手发放问卷并收集有效样本360份,通过SPSS 27.0和AMOS 24.0数据分析软件分析数据的可靠性,并利用Process 4.0进行层次回归分析验证理论模型。结果表明:时间压力和竞争氛围感知可以显著正向影响不安全驾驶行为;安全态度可以显著负向影响外卖骑手不安全驾驶行为;安全态度可以介导时间压力与不安全驾驶行为的关系,也能介导竞争氛围感知与不安全驾驶行为的关系;示范性规范可以正向调节安全态度与不安全驾驶行为的关系。

考虑及时交货和平台商誉的供应链动态决策研究——基于突发事件的视角

供应链在运营过程中不可避免会遭遇突发事件。文章针对发生时间具有随机性,且损害及时交货和平台商誉的突发事件对供应链成员的影响,构建由供应商、平台和零售商组成的三级供应链,探讨了非合作、成本分担和协同合作三种模式下的决策,利用动态微分博弈理论求解不同模式下各成员的最优策略。研究发现:供应商会根据及时交货水平损害率的高低决定突发事件发生后的交货策略,突发事件发生后平台的成本分担行为侧重于扩大市场需求和提升零售商的促销积极性,但对平台商誉水平的提升效果并不明显。协同合作模式下各均衡决策结果均为最优;与非合作模式相比,成本分担模式能够显著提升突发事件发生前后供应商及时交货水平、突发事件发生前平台商誉水平,并实现整体利润的提升。

基于层级结构的空−地协同预设时间最优容错控制

研究了发生执行器故障的无人机−无人车异构编队系统的层级预设时间最优编队控制问题.以保容错性能和收敛速度的优化控制为研究主线,以层级控制、图博弈理论和预设时间控制为技术基础,构建了一种预设时间最优容错控制算法.虚拟层设计了基于一致性跟踪误差和能量消耗的二次型性能指标函数,借助耦合哈密顿−雅克比−贝尔曼(Hanmilton-Jacobi-Bellman,HJB)方程和强化学习求解近似最优控制策略,实现多智能体的同步最优控制和交互纳什均衡.实际控制层基于最优信号并利用滑模控制和自适应技术,设计了预设时间容错跟踪控制器,实现对最优编队轨迹的有限时间跟踪.在保证全局收敛时间完全不依赖于系统的初始状态和控制器参数的同时,也有效实现对执行器故障参数的逼近.最后,通过仿真实验验证了所提控制策略的有效性.

基于加速度计阵列的乒乓球智能判分系统

乒乓球比赛在国际比赛、体育教学、休闲健身等领域备受关注。针对乒乓球比赛中裁判员主观局限性导致的判分人为误差、球员训练效率与实时性差等问题,提出了一种基于MEMS加速度计阵列的乒乓球智能判分系统。为了精准检测桌面落球位置,采用ADXL335加速度传感器模块测量球-桌碰撞引起的桌面振动信息。通过优化加速度传感器阵列节点,开发多信号协同感知算法,实现球桌表面落球点的精确定位。此外,结合落球点坐标信息,开发了基于国际乒乓球比赛规则的智能判分和比分实时显示上位机模块。实验结果表明:所开发的乒乓球判分系统具有智能裁判、比分实时显示、落球点精准定位、坐标信息存储等功能,为乒乓球比赛精准智能裁判和球员数字化训练提供了一种实用的设计方案。

Stackelberg微分博弈下的鲁棒最优投资-再保险问题

考虑一个以模糊厌恶再保险公司为领导者,模糊中立保险公司为追随者的Stackelberg随机微分博弈问题.通过求解拓展的HJB(Hamilton-Jacobi-Bellman)方程组,给出时间一致性均值-方差准则下的鲁棒最优投资-再保险策略以及相应的值函数.最后,通过数值例子和敏感性分析说明最优策略与主要参数之间的关系.

区域海事事故治理效果动态综合评价

为准确评价区域海事事故治理效果,通过构建动态综合评价模型,为水上交通安全规划提供决策依据。首先,从事故的绝对指标与相对指标角度出发,建立包含8个指标的区域海事事故治理效果评价指标体系。其次,使用博弈赋权法对熵权法所得权重和指标相关性权重确定法(Criteria Importance Through Intercriteria Correlation, CRITIC)所得权重进行组合,以确定各时段评价指标组合权重,并采用逼近理想解排序法(Technique for Order Preference by Similarity to Ideal Solution, TOPSIS)对各地区海事事故治理效果进行各时段静态综合评价。再次,通过混合时序算子集结各时段静态综合评价值,求得各地区海事事故治理效果的动态综合评价值,进而判断各地区海事事故的治理效果。最后,运用所建评价模型对2017—2021年上海、浙江、广东和山东4个地区海事事故治理效果进行动态综合评价。研究结果显示:与单一赋权TOPSIS法相比,博弈赋权-TOPSIS法所得静态综合评价结果更为合理可靠;与单一时序算子相比,混合时序算子所得动态综合评价结果更为合理可靠;随着海事事故治理策略和治理强度不同,上海和广东地区海事事故治理效果呈上升趋势,而浙江和山东地区海事事故治理效果呈下降趋势;广东地区海事事故治理效果稳定性最强,而浙江地区海事事故治理效果稳定性最弱;上海地区海事事故治理效果最好,而浙江地区海事事故治理效果最差。

ϵ-Nash mean-field games for stochastic linear-quadratic systems with delay and applications

In this paper,we focus on mean-field linear-quadratic games for stochastic large-population systems with time delays.The ϵ-Nash equilibrium for decentralized strategies in linear-quadratic games is derived via the consistency condition.By means of variational analysis,the system of consistency conditions can be expressed by forward-backward stochastic differential equations.Numerical examples illustrate the sensitivity of solutions of advanced backward stochastic differential equations to time delays,the effect of the the population's collective behaviors,and the consistency of mean-field estimates.

基于协同估计的三维多导弹博弈制导律

针对三维空间中多导弹协同拦截机动目标的挑战,基于广义零控脱靶量概念,提出一种新的多导弹协同博弈性能目标函数和分布式抗饱和扩张状态观测器。首先,建立一个三维多导弹拦截机动目标的非线性模型,并提出了一种精确的零控脱靶量计算方法。基于此方法,构建了多导弹协同拦截的博弈性能目标函数,并设计了基于信息融合理论的分布式抗饱和扩张状态观测器对机动目标的机动加速度进行协同估计。最后采用了哈里斯鹰粒子群优化算法来计算制导指令,旨在以最优的燃料消耗实现最优的拦截效果。通过对4种不同交战场景的仿真实验,验证了该协同博弈制导律的优越性和有效性。