关键词： Economic model   Eradication   Surveillance   Bovine viral diarrhoea virus  

摘要： Economic analyses are indispensable as sources of information to help policy makers make decisions about mitigation resource use. The aim of this study was to conduct an economic evaluation of the Swiss national mitigation programme for bovine viral diarrhoea virus (BVDV), which was implemented in 2008 and concludes in 2017. The eradication phase of the mitigation programme comprised testing and slaughtering of all persistently infected (PI) animals found. First, the whole population was antigen tested and all PI cattle removed. Since October 2008, all newborn calves have been subject to antigen testing to identify and slaughter PI calves. All mothers of PI calves were retested and slaughtered if the test was positive. Antigen testing in calves and elimination of viruscarriers was envisaged to be conducted until the end of 2011. Subsequently, a surveillance programme will document disease freedom or detect disease if it recurs. Four alternative surveillance strategies based on antibody testing in blood from newborn calves and/or milk from primiparous cows were proposed by Federal Veterinary Office servants in charge of the BVDV mitigation programme. A simple economic spreadsheet model was developed to estimate and compare the costs and benefits of the BVDV mitigation programme. In an independent project, the impact of the mitigation programme on the disease dynamics in the population was simulated using a stochastic compartment model. Mitigation costs accrued from materials, labour, and processes such as handling and testing samples, and recording results. Benefits were disease costs avoided by having the mitigation programme in place compared to a baseline of endemic disease equilibrium. Cumulative eradication costs and benefits were estimated to determine the break-even point for the eradication component of the programme. The margin over eradication cost therefore equalled the maximum expenditure potentially available for surveillance without the net benefit from

关键词： 中国经济   宏观经济   模型显示   经济增长   货币政策   进出口  

摘要： 2012年下半年，由于欧元区经济持续低迷，中国进出口增速有可能再次下滑，对中国经济增长产生下行压力。如果继续实行适度宽松货币政策，今年中国经济增速仍可在8％。

关键词： 收入差距   城乡居民   检验分析   影响因素   城乡二元经济结构   经济发展水平   经济模型   刘易斯  

摘要： 按照刘易斯的二元经济模型,利用最近30年的数据对城乡居民收入差距的影响因素进行Granger检验分析.结论认为,经济发展水平的提高在前期会扩大城乡居民收入差距.当经济发展到一定水平特别是城乡二元经济结构被打破后,经济的发展会使得城乡居民的收入差距程度降低,并维持在一个合理的水平.

关键词： 货币政策   粘性信息   菲利普斯曲线  

摘要： 粘性信息理论是近十年来新型不完全信息理论之一,文章以SVAR模型来拟合中国货币政策的特征,并以此作为基准模型,借助菲利普斯曲线,同时还引入传统凯恩斯的粘性价格模型,作为比较的模型,从而来检验粘性信息模型在中国的适应性。

关键词： 科技成果鉴定   配煤工艺   仿真技术   炼焦煤   洗煤厂   经济模型   集团公司   产品结构  

摘要： 9月14日，神华宁夏煤业集团公司大武口洗煤厂研发的”炼焦煤混配工艺仿真技术应用研究”通过了科技成果鉴定。该项目采用先进的算法建立基于炼焦煤混配经济模型，在该模型的指导下产品结构的优化，克服了传统的炼焦煤过程中，

关键词： 收入差距   所有制结构   二元经济结构   影响因素  

摘要： 深化收入分配制度改革,增加城乡居民收入是我国改革的根本目标。改革开放以来,我国的经济持续快速发展,人民的生活水平得到了很大提高,但与此同时,我国也出现了严重的居民收入差距。文章在对收入分配的影响因素进行分析的基础上,建立一个回归模型分析所有制结构的演变与居民收入的关系,进而通过协整分析和格兰杰因果检验,对二元经济结构与城乡居民收入差距之间的数量关系进行了分析和检验。研究结论表明:转型期所有制结构的演变以及二元经济结构是我国居民收入差距呈扩大趋势的根本原因,二元经济结构与城乡居民收入差距具有单向的格兰杰原因。最后针对城乡收入差距扩大的趋势提出相应的解决对策。

关键词： Nonlinear systems   Economic optimization   Model predictive control   State estimation   Output feedback control   Chemical process control  

摘要： In this work, we focus on a class of nonlinear systems and design an estimator-based economic model predictive control (MPC) system which is capable of optimizing closed-loop performance with respect to general economic considerations taken into account in the construction of the cost function. Working with the class of full-state feedback linearizable nonlinear systems, we use a high-gain observer to estimate the nonlinear system state using output measurements and a Lyapunov-based approach to design an economic MPC system that uses the observer state estimates. We prove, using singular perturbation arguments, that the closed-loop system is practically stable provided the observer gain is sufficiently large. We use a chemical process example to demonstrate the ability of the state-estimation-based economic MPC to achieve process time-varying operation that leads to a superior cost performance metric compared to steady-state operation using the same amount of reactant material. (c) 2012 Elsevier B.V. All rights reserved.

关键词： laparoscopic   hepatectomy   ultrasound   cost analysis   computed tomography   magnetic resonance imaging  

摘要： Background and Objectives For small asymptomatic hepatic adenomas (HA), available data are insufficient to establish the superiority of either observation or surgery. We sought to investigate the cost-effectiveness of two initial management strategies. Methods We performed a comparative analysis of two theoretical cohorts of 100 patients with small (<5?cm), asymptomatic HA. Discounted cash flow (DCF) models compared the net present value (NPV) of both treatment options at year 10 under three distinct progression rate scenarios. A break-even (BE) analysis was used to determine the BE point at which the NPV for observation and immediate surgery intersect. Results The NPV for immediate surgery was $1,733,955. The NPV for observation varied between $2,065,315$2,745,631 for computed tomography (CT), $2,264,575$2,929,541 for magnetic resonance imaging (MRI), and $802,837$1,580,413 for ultrasound (US). The BE point was between 6 and 8 years for CT and 57 years for MRI. The BE point for US was not reached except in the highest progression rate scenario (12 years). Conclusions This study highlights the importance of the underlying progression rate and the cost of imaging when following patients with asymptomatic HA. Overall, US surveillance is the most cost-efficient approach to observing small asymptomatic HA. If cross-sectional imaging is utilized, then immediate surgery is the most cost-effective decision at 58 years. J. Surg. Oncol. 2012;106:491497. (c) 2012 Wiley Periodicals, Inc.

关键词： Cloud provider   Profit   Outsourcing   Federation  

摘要： Resource provisioning in Cloud providers is a challenge because of the high variability of load over time. On the one hand, the providers can serve most of the requests owning only a restricted amount of resources, but this forces to reject customers during peak hours. On the other hand, valley hours incur in under-utilization of the resources, which forces the providers to increase their prices to be profitable. Federation overcomes these limitations and allows providers to dynamically outsource resources to others in response to demand variations. Furthermore, it allows providers with underused resources to rent them to other providers. Both techniques make the provider getting more profit when used adequately. Federation of Cloud providers requires having a clear understanding of the consequences of each decision. In this paper, we present a characterization of providers operating in a federated Cloud which helps to choose the most convenient decision depending on the environment conditions. These include when to outsource to other providers, rent free resources to other providers (i.e., insourcing), or turn off unused nodes to save power. We characterize these decisions as a function of several parameters and implement a federated provider that uses this characterization to exploit federation. Finally, we evaluate the profitability of using these techniques using the data from a real provider.

关键词： Supply chain risk management   Quality management   Control chart   keiretsu  

摘要： We present a quality risk management model for a supplier-assembler structure supply chain. To mitigate quality risks, supply chain members are coordinated by sharing their information. A good example of such supply chain is the keiretsu of Japanese automobile industries. To be able to quick respond to the assembler's feedback (e.g., quality problems) has become a key point of a supplier's competitive edge. This ability is also useful for removing bottlenecks among a supply chain. In the setting of a due-date to treat an assignable cause, because idle risk and delay risk have a trade-off relationship, find out the optimal due-date becomes a problem of great interest to the supplier. We develop a P-chart solution model to help suppliers find out the optimal due-date that minimizes the total cost. We also clarify the relations among various risks by analyzing proposed model. We find that a longer due-time should be set when either the sampling interval is longer or a high quality is demanded. (C) 2012 Elsevier B.V. All rights reserved.