大数据背景下区域木材物流配送中心选址

指出了我国木材物流存在的主要问题以及解决方案,结合大数据技术,利用遗传算法进行木材物流配送中心的选址,建立了数学模型并进行了案例分析,以达到对木材物流成本和服务的优化。     

供应链视角下餐饮O2O模式的配送路径优化

O2O最后一公里配送往往需要综合考虑时间和成本的关系,研究平台对订单的分配和路径优化对提升O2O供应链的整体效率和产业链升级具有十分重要的意义。从餐饮商家和O2O平台两个主要参与者出发对物流配送系统进行研究,提出了适合于O2O餐饮供应链的配送网络,并考虑道路阻塞、最大里程数等约束,搭建了上层模型最短时间、下层模型最低成本的双层规划模型,进而通过NSGA-Ⅱ算法求得可行解,最后验证了算法的可行性,为进一步研究O2O配送提供了新的解决思路。     

石油海运领域运筹优化方法应用研究综述

为研究运筹方法在石油海运领域的应用及前景,检索1980年至今的国内外相关文献,系统归纳提出石油海上运输优化问题的场景分类:海上运输优化、在港作业调度优化以及油船驳运,分析并对比了各研究的模型差异及算法优劣,最后提出了全局优化调度、根据实际添加特殊约束和设置变量、利用规划约束及人工智能等方式弥补线性规划求解的不足等研究建议。     

Optimizing a portfolio of mean-reverting assets with transaction costs via a feedforward neural network

Optimizing a portfolio of mean-reverting assets under transaction costs and a finite horizon is severely constrained by the curse of high dimensionality. To overcome the exponential barrier, we develop an efficient, scalable algorithm by employing a feedforward neural network. A novel concept is to apply HJB equations as an advanced start for the neural network. Empirical tests with several practical examples, including a portfolio of 48 correlated pair trades over 50 time steps, show the advantages of the approach in a high-dimensional setting. We conjecture that other financial optimization problems are amenable to similar approaches.     

Islamic and conventional portfolios optimization under investor sentiment states: Bayesian vs Markowitz portfolio analysis

This paper investigates the portfolio optimization under investor’s sentiment states of Hidden Markov model and over a different time horizon during the period 2004–2016. To compare the efficient portfolios of the Islamic and the conventional stock indexes, we have employed two approaches: the Bayesian and Markowitz mean-variance. Our findings reveal that the Bayesian efficient frontier of Islamic and conventional stock portfolios is affected by the investor’s sentiment state and the time horizon. Our findings also indicate that the investor’s sentiment regimes change the Islamic and the conventional optimal diversified portfolios.Moreover, the results show that the potential diversification benefits seem to be more important when using the Bayesian approach than when applying the Markowitz approach. This finding is valid for the bearish, depressed, bullish and calm states in Islamic stock markets. However, the diversification of potential portfolios is significant only for the bullish and the bubble states in the conventional financial markets.The findings of the study provided additional evidence for investors to exploit googling investor sentiment states to evaluate the portfolio performance and make an optimal portfolio allocation.     

我国林业扶贫工作的主要问题及优化措施研究

林业扶贫是当前我国扶贫工作的重要内容。通过介绍开展林业扶贫工作的政策背景、理论背景以及经济背景,分析林业扶贫工作开展过程中存在的基础设施落后、针对性差等问题,提出了因地制宜,互联网+林业扶贫,鼓励社会资本进入扶贫工作、志智双扶等应对措施。     

制度距离、投资动机与企业OFDI区位选择——中国对外直接投资“制度风险偏好”的一种解释

由于企业的对外直接投资（OFDI）存在制度适应成本，东道国与母国之间的制度距离会对企业OFDI产生负向影响。基于2003—2015年中国对140个国家和地区OFDI的分析表明：中国企业的OFDI具有明显的市场寻求动机和战略资源寻求动机，其中，市场寻求型OFDI表现出显著的互补效应，战略资源寻求型OFDI表现出一定程度的挤出效应；东道国与中国的制度距离会通过投资动机影响中国企业OFDI的区位选择，即倾向于向制度距离较小的国家和地区进行OFDI，且制度距离会弱化市场寻求型OFDI的互补效应和战略资源寻求型OFDI的挤出效应。站在企业角度来看，中国企业在进行OFDI时并不具有“制度风险偏好”，而是表现出“制度风险规避”特征：选择对其自身发展来讲制度风险较小（制度距离较小）的目标市场进行OFDI。因此，中国应深化市场经济体制改革，提升国内制度质量，加强国际经济合作，并增强企业的制度适应能力，以有效减小制度距离对企业OFDI区位选择的约束，进而优化OFDI区位分布，提高OFDI效益和质量。     

Sharing the value‐at‐risk under distributional ambiguity

This paper considers the problem of risk sharing, where a coalition of homogeneous agents, each bearing a random cost, aggregates their costs, and shares the value‐at‐risk of such a risky position. Due to limited distributional information in practice, the joint distribution of agents' random costs is difficult to acquire. The coalition, being aware of the distributional ambiguity, thus evaluates the worst‐case value‐at‐risk within a commonly agreed ambiguity set of the possible joint distributions. Through the lens of cooperative game theory, we show that this coalitional worst‐case value‐at‐risk is subadditive for the popular ambiguity sets in the distributionally robust optimization literature that are based on (i) convex moments or (ii) Wasserstein distance to some reference distributions. In addition, we propose easy‐to‐compute core allocation schemes to share the worst‐case value‐at‐risk. Our results can be readily extended to sharing the worst‐case conditional value‐at‐risk under distributional ambiguity.     

Forecast of realized covariance matrix based on asymptotic distribution of the LU decomposition with an application for balancing minimum variance portfolio

We derive the asymptotic distribution for the LU decomposition, that is, the Cholesky decomposition, of realized covariance matrix. Distributional properties are combined with an existing generalized heterogeneous autoregressive (GHAR) method for forecasting realized covariance matrix, which will be referred to as a generalized HARQ (GHARQ) method. An out-of-sample forecast comparison of a real data set shows that the proposed GHARQ method outperforms other existing methods in terms of optimizing the variances of portfolios.     

基于预约策略的医院CT设备使用优化研究

预约检查是对有限的医疗检查资源的一种调度优化。以攀枝花市A医院CT检查为例,通过实地调研,统计CT设备的服务能力,门诊患者,住院患者和急诊患者的平均到达率,接受患者的单位检查收益和拒绝患者的单位检查损失。通过调整预约策略使有限的资源设备产生更多的收益,并运用仿真模拟不同预约策略下的收益效果。研究结果对医院重要设备的预约使用提供了一定参考价值。