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1.
郭捷  谷利月 《运筹与管理》2022,31(3):112-118
农业供应链金融为涉农企业融资难问题提供了新思路。本文以上市涉农上市企业2016~2018年的财务数据为样本,探讨了农业供应链金融对缓解企业融资约束的影响,以及涉农企业参与精准扶贫对缓解融资约束的调节作用。研究发现:涉农企业普遍面临融资约束问题,而农业供应链金融显著缓解了涉农企业的融资约束,且对参与精准扶贫企业的融资约束缓解更为显著。本文揭示了:农业供应链金融能有效缓解涉农企业的融资约束问题,再次证明了农业供应链金融缓解涉农企业融资约束的重要性和必要性,拓展了供应链金融研究的领域,同时对企业参与精准扶贫,响应新时期涉农企业社会责任的具体要求,形成政府、企业等共同承担社会责任的多元化减贫治理机制,助力乡村振兴提供相应借鉴。  相似文献   
2.
本文对一氧化碳气体中毒问题的生理学基础进行分析 ,将其抽象为理想状态下的一个微分方程模型 ,得出了一个比较符合实际情况的结果 .此模型处理同类问题有一般意义  相似文献   
3.
Issuances in the USD 260 Bn global market of perpetual risky debt are often motivated by capital requirements for financial institutions. We analyze callable risky perpetual debt emphasizing an initial protection (‘grace’) period before the debt may be called. The total market value of debt including the call option is expressed as a portfolio of perpetual debt and barrier options with a time dependent barrier. We also analyze how an issuer’s optimal bankruptcy decision is affected by the existence of the call option by using closed-form approximations. The model quantifies the increased coupon and the decreased initial bankruptcy level caused by the embedded option. Examples indicate that our closed form model produces reasonably precise coupon rates compared to numerical solutions. The credit-spread produced by our model is in a realistic order of magnitude compared to market data.  相似文献   
4.
Fractional aircraft ownership programs, where individuals or corporations own a fraction of an aircraft, have revolutionized the corporate aviation industry. Fractional management companies (FMC) manage all aspects of aircraft operations enabling the owners to enjoy the benefits of private aviation without the associated responsibilities. We describe here the development of a scheduling decision support tool for a leading FMC. We present mathematical models, exact and heuristic solution methods. Our computational results using real and randomly generated data indicate that these models are quite effective in finding optimal or near-optimal solutions. The first phase of the implementation of one of these models at the FMC led to a significant improvement in effective utilization of the aircraft, reduction of costs due to reduced empty moves, and hence increased profits.  相似文献   
5.
随着我国报废汽车数量的增多,由其造成的交通隐患、环境污染和资源浪费已成为重要社会问题,而如何设计合理可行的回收模式成为解决问题的关键。以制造商主导为前提,提出了基于企业社会责任的报废汽车回收模型,构建了制造商回收、销售商回收和第三方回收模式下的回收流程和数学模型,通过实例对考虑和不考虑企业社会责任两种情况下的回收模型进行了分析,探讨了不同政府奖励下报废汽车回收模式的策略选择。通过研究发现:(1)不论是否考虑企业社会责任,随着政府奖励的增加,制造商最终都会选择由自己进行回收;(2)当考虑企业社会责任时,政府奖励和决策者经济责任偏好都会导致决策的改变,随着政府奖励和赋予经济责任权重的同步增加,制造商的决策由第三方企业回收模式或销售商回收模式变成了制造商回收模式,表明政府奖励和企业社会责任对报废汽车回收模式选择具有显著影响。  相似文献   
6.
本文基于我国172家企业的问卷调查数据,运用结构方程模型,对企业可持续供应链管理实践及其对绩效的影响进行实证分析。结果表明,企业实现内部可持续管理能够对企业管理供应商的行为有着显著的影响;同时,企业管理供应商的行为作为企业外部管理实践对企业的绩效有着显著的正向影响;在企业绩效中,环境绩效和社会绩效对经济绩效有着显著的正向影响,企业的外部管理实践能够通过环境绩效和社会绩效的提高实现最终经济绩效的明显增加。  相似文献   
7.
随着以希腊债务危机为导火索的欧洲债务危机的愈演愈烈,国债对宏观经济的影响再一次成为了经济学讨论的热点.首先从直观图形着手,运用H-P滤度法去除趋势后,计算各变量的偏离趋势百分比,对比国债规模代替变量与宏观经济效应代替变量之间的偏离趋势图,从图形得到的定量关系为后面的实证分析做好准备.然后进一步进行协整分析,并在向量自回归(VAR)框架下通过脉冲响应函数考察变量之间的相互影响路径,最后通过建立误差修正模型(ECM)分析各个变量之间的长期均衡关系和短期波动特征,以量化各变量之间影响程度的大小.全面系统地研究了国债对宏观经济增长的影响程度并做出实证分析,对于深刻认识国债的本质,规避国债的风险,科学合理地制定国债政策有着重要的理论价值和实际意义.  相似文献   
8.
In this paper, we explore a pricing model for corporate bond accompanied with multiple credit rating migration risk and stochastic interest rate. The bond price volatility strongly depends on potentially multiple credit rating migration and stochastic change of interest rate. A free boundary problem of partial differential equation is presented, which is the equivalent transformation of the pricing model. The existence, uniqueness, and regularity for the free boundary problem are established to guarantee the rationality of the pricing model. Due to the stochastic change of interest rate, the discontinuous coefficient in the free boundary problem depends explicitly on the time variable but is convergent as time tends to infinity. Accordingly, an auxiliary free boundary problem is constructed, whose coefficient is the convergent limit of the coefficient in the original free boundary problem. With some constraint on the risk discount rate satisfied, we prove that a unique traveling wave exists in the auxiliary free boundary problem. The inductive method is adopted to fit the multiplicity of credit rating. Then we show that the solution of the original free boundary problem converges to the traveling wave in the auxiliary free boundary problem. Returning to the pricing model with multiple credit rating migration and stochastic interest rate, we conclude that the bond price profile can be captured by a traveling wave pattern coupling with a guaranteed bond price with face value equal to one at the maturity.  相似文献   
9.
黄学庭 《运筹与管理》2007,16(3):151-154
本文首先根据收益增长率等于再投资额与再投资收益率的乘积这一基本结论,对超常增长而后无增长的威斯通模型作了一点修正;接着分析了该模型中隐含的企业总投资资本利润率;最后根据微观经济学理论探讨了企业在无增长阶段可能面临的不同竞争状况对其未来盈利能力和现金流的影响,建立了更具普遍性的估价模型.  相似文献   
10.
Governments borrow funds to finance the excess of cash payments or interest payments over receipts, usually by issuing fixed income debt and index-linked debt. The goal of this work is to propose a stochastic optimization-based approach to determine the composition of the portfolio issued over a series of government auctions for the fixed income debt, to minimize the cost of servicing debt while controlling risk and maintaining market liquidity. We show that this debt issuance problem can be modeled as a mixed integer linear programming problem with a receding horizon. The stochastic model for the interest rates is calibrated using a Kalman filter and the future interest rates are represented using a recombining trinomial lattice for the purpose of scenario-based optimization. The use of a latent factor interest rate model and a recombining lattice provides us with a realistic, yet very tractable scenario generator and allows us to do a multi-stage stochastic optimization involving integer variables on an ordinary desktop in a matter of seconds. This, in turn, facilitates frequent re-calibration of the interest rate model and re-optimization of the issuance throughout the budgetary year allows us to respond to the changes in the interest rate environment. We successfully demonstrate the utility of our approach by out-of-sample back-testing on the UK debt issuance data.  相似文献   
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