基于粒子群算法下的交叉口信号配时优化

为了合理地优化交叉口信号配时,通过分析交叉口的评价指标,建立了以车辆的平均延误、停车次数最小、交叉口整体通行能力最大、各相位有效绿灯时间和交叉口周期时长作为约束条件的数学模型。并通过改进前人研究基础上的动态加权系数,将多目标的非线性优化问题转化为单一目标的非线性规划问题,为了得出更科学稳定的解,提出了改善粒子群算法系统稳定性的2种方法,并将其与粒子群算法结合起来。然后以Matlab为求解工具,结合临邑市某一交叉口实例进行求解分析。最后的结果表明,在使用改进后的粒子群算法进行优化后交叉口通行能力较之现状提升了9%,延误下降了28%,停车次数下降了9%,且各项优化结果均优于Webster,改进后的算法在程序中运行300代,到216代才开始收敛,而未改进的算法稳定性较差,优化结果和收敛曲线则随着实验次数的变化而变化,最后的结论证明了该算法和模型的可靠性。     

Don't patronize me! An experiment on preferences for authorship

Do people only reject interference and keep control to affect the outcome? We find that 20% of subjects reject unrequired help and insist on their solution to a problem—although doing so is costly and does not change the result. We tease out the motives by varying the information available to the interfering party (paternalist). Subjects do not resist to show to the paternalist that they were able to find the correct solution. Instead, two motives seem to play a role. First, subjects prefer to have produced or “authored” the solution themselves. Second, subjects desire to signal their authorship and hence their independence to the paternalist.     

不同的干制方法对木瓜提取液中黄酮含量的影响

本文主要研究了不同的干燥方法对木瓜提取液中黄酮含量的影响。实验结果表明热风干燥木瓜提取液的黄酮损失最严重,最低含量为2.7%;组合干燥次之,最低含量达3.1%;而真空干燥木瓜提取液中黄酮损失最少,最低含量为3.6%。     

An evaluation of heuristic methods for determining the best table mix in full-service restaurants

Little research has been done on the optimal mix of supply in service businesses that maximizes revenue. Our research context is the full-service restaurant table mix problem. This problem, which is quite new to the literature, finds the optimal number of different size tables for a restaurant to maximize its value (revenue or contribution) generating potential. Specifically, we examine the effectiveness of eight heuristic techniques for the problem using two experiments. The first experiment uses data from a 240-seat full-service restaurant to evaluate all eight heuristics, while the second experiment investigates the performance of selected heuristics under a broader set of environmental factors. The results of our first experiment showed that the better of the simulated annealing heuristic variants yielded the optimal solution in seven of eight test problems, averaging within 0.1% of optimal. Our second experiment showed that the simplest of the models we investigated yielded solutions within 1% of the simulated annealing solution. Finally, we observed that altering the table mix on a daily basis increased performance by over 1% compared to maintaining the optimal weekly table mix.     

姜黄素提取条件的正交设计及硅胶柱色谱纯化的研究

目的:优化姜黄药材中总姜黄素的提取和纯化最佳工艺条件。方法:采用正交设计优化乙醇回流法提取中药材姜黄中姜黄素的条件,然后以氯仿-甲醇溶液为洗脱液,采用硅胶柱色谱分离法对姜黄素提取液进一步纯化,以提取物得率、总姜黄素含量和纯度为考察指标。采用HPLC法对姜黄素提取液、纯化后的总姜黄素含量、纯度进行检测。结果:通过正交设计发现温度90℃,乙醇浓度75%,料液比10倍,提取时间3h提取率最高;采用硅胶柱色谱分离法对姜黄素提取液进一步纯化后纯度可以达到81.8%。结论:该提取条件下提取工艺合理、科学。     

The forward method as a solution refinement in rational expectations models

This paper generalizes the standard forward method of recursive substitution to a general class of linear rational expectations models with potentially multiple fundamental solutions. It is shown that the existence and uniqueness of the well-known forward solution are preserved in a general context. We also propose a key property embedded in the forward solution - the no-bubble condition - as an economically sensible solution refinement in the class of fundamental solutions. In the literature, the no-bubble condition has been assumed to rule out non-fundamental bubble solutions. We show that the forward solution is the only rational expectations equilibrium satisfying the no-bubble condition and consequently, it is the most relevant fundamental solution within the class of fundamental equilibria. Several economic examples are provided where the fundamental solutions obtained by other solution methods and refined by other solution selection criteria violate the no-bubble condition.     

不同处理对紫花苜蓿在干旱条件下种子萌发的影响

[目的]为了寻找一种在干旱条件下,能提高紫花苜蓿种子活力,增强其幼苗抗旱机能的有效方法。[方法]采取CaCl2溶液浸泡、水浴加热及微波辐射等3种不同方法对紫花苜蓿种子进行预处理,在20%的PEG—6000溶液模拟干旱条件下,研究其发芽率,发芽势及种子活力指数的影响。[结论]CaCl2溶液浸泡及25～35℃之间水浴加热处理对紫花苜蓿种子的萌发有促进作用,高温水浴加热及微波辐射处理对紫花苜蓿种子的萌发有抑制作用。     

On the dominance of capitalists leadership in a ‘Feedback-Stackelberg’ solution of a differential game model of capitalism

This paper deals with a modified version of the Lancaster model of capitalism, where it is assumed that there is a cost jointly borne by the two groups of players (workers versus capitalists) and associated with the bargaining of a larger share of consumption for the workers. It is shown that a Feedback- Stackelberg solution, with the capitalists acting as leaders and announcing their investment policy at the beginning of each period, is a solution dominating the Feedback-Nash solution. The paper is also intended to be a tutorial on the Feedback-Stackelberg solution, a concept not so often used by economic modelers.     

Specification testing in nonparametric instrumental variable estimation

In nonparametric instrumental variable estimation, the function being estimated is the solution to an integral equation. A solution may not exist if, for example, the instrument is not valid. This paper discusses the problem of testing the null hypothesis that a solution exists against the alternative that there is no solution. We give necessary and sufficient conditions for existence of a solution and show that uniformly consistent testing of an unrestricted null hypothesis is not possible. Uniformly consistent testing is possible, however, if the null hypothesis is restricted by assuming that any solution to the integral equation is smooth. Many functions of interest in applied econometrics, including demand functions and Engel curves, are expected to be smooth. The paper presents a statistic for testing the null hypothesis that a smooth solution exists. The test is consistent uniformly over a large class of probability distributions of the observable random variables for which the integral equation has no smooth solution. The finite-sample performance of the test is illustrated through Monte Carlo experiments.     

基于遗传算法轿车焊装车间车辆路径优化

遗传算法是一种模拟自然进化过程搜索最优解的方法。通过建立某轿车焊装车间车辆路径问题数学模型,然后利用遗传算法求解该问题,最后在Matlab软件中进行编程求解,有效地求解出问题的最优解或近似最优解。     

Some results on analytic optimal control solution of a simple rational expectations model

In this note, we correct a technical error in a well-known stabilization analysis in the context of a simple macroeconomic model, formulated as an optimal control problem. This error originated in a slip in an unpublished but widely circulated paper by D.A. Livesey, suggesting a procedure for obtaining a solution to a class of optimal control problems frequently encountered in a stabilization literature. We then propose an ad hoc solution method which makes clear the intuition of the solution to the particular model to which the Livesey method was applied, and of the larger class of models to which it belongs. Our solution is so formulated that the contrast between it and the Livesey result is made transparent.     

Coalition formation in general NTU games

A general nontransferable utility (NTU) game is interpreted as a collection of pure bargaining games that can be played by individual coalitions. The threatpoints or claims points respectively, in these pure bargaining games reflect the players' opportunities outside a given coalition. We develop a solution concept for general NTU games that is consistent in the sense that the players' outside opportunities are determined by the solution to a suitably defined reduced game. For any general NTU game the solution predicts which coalitions are formed and how the payoffs are distributed among the players.     

The market area problem with two plants

This paper considers a two-plant production and distribution problem where the production cost of each plant depend on the amount produced. Demand is price inelastic and uniformly distributed on the plane. Transport costs are directly proportional to the straight-line travel distance from each plant. The constant of proportionality may differ between plants. Two cases are considered: (i) the two plants are owned by a single supplier, and (ii) the two plants are operated by competing firms. The profit-maximizing solution, when convexity assumptions are imposed on the production cost functions, determines the amount produced in each plant and defines the marketing region for each plant. It is shown that the solution for the single supplier case is identical to the solution in the competitor case and that the solution for each case is unique.     

一种新的地方政府债务风险预警系统设计与应用

本文围绕构建地方政府债务风险预警系统,首先综合运用TOPSIS法和德尔菲法确定了样本的债务风险综合评价值;然后利用支持向量机,提出了基于结构风险最小化的地方政府债务风险预警模型,并将该模型的求解转化为非线性规划仅有线性约束问题,解决了传统方法中忽略模型置信范围、需要样本数量大及过度学习等缺陷。在实证研究中,基于训练样本的模型平均绝对百分精度达99. 69%,基于检验样本的模型平均绝对百分精度达96. 99%,数值结果表明本文所设计的地方政府债务风险预警系统是有效的,可行的。     

Cost sharing: efficiency and implementation

We study environments where a production process is jointly shared by a finite group of agents. The social decision involves the determination of input contribution and output distribution. We define a competitive solution when there is decreasing-returns-to-scale which leads to a Pareto optimal outcome. Since there is a finite number of agents, the competitive solution is prone to manipulation. We construct a mechanism for which the set of Nash equilibria coincides with the set of competitive solution outcomes. We define a marginal-cost-pricing equilibrium (MCPE) solution for environments with increasing returns to scale. These solutions are Pareto optimal under certain conditions. We construct another mechanism that realizes the MCPE.     

Limited-dependent rational expectations models with future expectations

This paper examines limited-dependent rational expectations (LD-RE) models containing future expectations of the dependent variable. Limited dependence is of a two-limit tobit variety which may, for example, arise as a result of a policy of imposing limits on the movement of the dependent variable by means of marginal as well as intramarginal interventions. We show that when the forcing variables are serially independent the model has an analytical solution which can be computed by backward recursion. With serially correlated forcing variables, we discuss an approximate solution method, as well as a numerically exact method that, in principle, can be implemented by stochastic simulation, although in practice it is limited by available computational capacity. The paper discusses some properties of the approximate solutions and reports the results of a limited number of Monte Carlo experiments in order to illustrate the computational feasibility of using the exact solution when the fundamentals are serially independent and the approximate solution when they are serially correlated.     

Generating price‐effective intermodal routes

We describe the problem of intermodal international freight transport that is faced by some logistic service providers and the solution that ORTEC's logistic suite offers to these customers. This solution is based on a state of the art k‐shortest path algorithm for directed networks. Our focus is on the modeling aspects of the problem. In particular, we propose an approach in two phases and methods to reduce the size of the network, so as to obtain a solution within an acceptable calculation time.     

Efficiency and monotonicity of bargaining solutions

A continuity axiom for bargaining solutions is introduced, which is satisfied by all Pareto optimal and continuous (in the Hausdorff metric) solutions. It is shown by two examples how this axiom can be used to characterize solutions having certain kind of monotonicity properties. One of the solutions is the lexicographic maximin solution. The other is the lexicographic extension of the Kalai-Smorodinsky solution. The former is an efficient (Pareto optimal) extension of the symmetric proportional solution. The latter is an efficient extension of the Kalai-Smorodinsky solution.     

Neoliberalism is Dead … Long Live Neoliberalism!

In this essay I argue that the ideology of neoliberalism may have failed, but that neoliberal practice is alive and kicking. Most of the ‘solutions’ to the crisis are in the spirit of neoliberalism, rather than enraptured by neoliberal spirit. Yet, this neoliberal solution is not a solution; it is part of the problem in the sense that it is leading to more problems — not just today but also in decades to come. This so‐called solution is often presented as Keynesian, but it is only partly so. A better way to classify this solution is as an attempt to save the existing, neoliberal, system. The big crisis of our time did not become a crisis of the hegemony of neoliberalism, because actually existing neoliberalism is flexible enough to influence policy in other ways than through the mantra of free markets: it thrives on presenting existing socioeconomic conditions as failing and neoliberalism as the best solution. Considering the many blows neoliberal ideology has received during this crisis, it should already be dead, but like a creeping cancer neoliberal practice is able to resurface and show up in both new and unexpected, and old and predictable, ways.     

The UK housing market and the monetary policy transmission mechanism: An SVAR approach

I estimate an eight variable structural vector autoregression (SVAR) model of the UK economy based upon that of Kim and Roubini [Kim, S., Roubini, N., 2000. Exchange rate anomalies in the industrial countries: a solution with a structural VAR approach. J. Monet. Econ. 45(3), 561–586] for the purpose of investigating the role of the housing market in the transmission of monetary policy. Retail sales fall by just under 0.4% following a temporary positive 100 basis points shock to short-term domestic interest rates; inflation is also lowered. House prices fall by 0.75%. House price shocks increase consumption, the price level and interest rates. Combining the central estimates for interest rate and house price shocks suggests that house price movements can explain about one-seventh of the fall in consumption following an interest rate shock. A counterfactual simulation comes to a similar figure.