洞庭湖的演化与生态

洞庭湖会消亡，三峡水库运行只能延长其寿命，是目前的主导认识。根据构造沉降和泥沙淤积的相对关系，近100年来洞庭湖的演化经历了下荆江裁弯前后的萎缩和基本保持不变两个阶段；三峡水库蓄水135m高程标志着进入湖的扩大阶段；洞庭湖湿地生态系统受洞庭湖演化、“泥沙淤积搬家”和三峡水库年内下泄量变化等三个主要因素的影响，在其综合作用下，湿地生态系统由顺向演替转化为逆向演替。如此，三峡水库运行将使洞庭湖的生态问题出现一系列新的变化，将成为湖区可持续发展等同于防洪的重大问题。     

Managing service shutdowns: Cash refunds or vouchers?

Service shutdowns—extended disruptions of operations—caused by exogenous events are on the rise. Such shutdowns pose major challenges for service providers, customers, and regulators. Providers prefer vouchers as a means of service recovery to limit bankruptcy risk, whereas customers demand cash refunds or vouchers that include a generous bonus. Regulators, on the other hand, insist that customers must be granted the right to be reimbursed in cash. This paper shows that a zero bonus is optimal under the voucher-only strategy, whereas the provider should always include a positive bonus with the voucher under the hybrid strategy that allows customers to choose between the cash refund and voucher options. Surprisingly, despite its higher flexibility in service recovery design, the hybrid strategy can be dominated by the voucher-only strategy in terms of profit and welfare. Moreover, we show that the ranking of strategies differs across the two important dimensions of expected profit and survival under shutdown. Finally, we study competition among providers and show that a high-quality provider is more likely to use cash-back as the service recovery strategy than its low-quality competitor.     

重庆市养老金支付存在的问题及建议

不合理的养老金支付条件、支付标准和较低的替代率,不仅导致重庆市退休职工生活水平下降,而且增大了社会养老保险金的支付压力.应根据重庆市老龄化及退休年龄及时调整养老保险金的支付条件和支付标准,提高养老金替代率.     

Economic consequences of the Home Appliance Eco-Point Program in Japan: a dynamic discrete choice approach

This study combined a dynamic discrete choice model for air conditioner replacement decisions with an inter-industry model in order to evaluate the economic impact of Japan’s Home Appliance Eco-Point Program, an appliance replacement program that was in effect from May 2009 to March 2011. Focusing on air conditioners produced from 1995 to 1999 and replaced during the period from 2005 to 2013, we found that the eco-point program increased replacement probabilities by 1.5% to 1.9% in 2009. Moreover, the program produced an additional output of 31,337 million yen and a total value added of 21,259 million yen. However, the benefit–cost ratio – determined by dividing the increase in value added by the monetary value of the points awarded for appliance replacement – was only 0.68. From a cost-benefit perspective, the program can be judged not to have been an effective policy measure.     

缴费年限对养老保险基金支付风险的影响研究

缴费年限直接影响着养老保险基金的缴费积累与参保者的待遇水平。能够领取养老金的缴费年限由最低缴费年限和退休年龄框定,参保者在缴费年限上具有较大的自主选择权。本文根据城镇职工基本养老保险现行制度设计,运用保险精算方法,构建了基金支付风险精算模型,并依据该模型实证评估了缴费年限对养老保险基金支付风险的影响。研究结果表明:单方面提高最低缴费年限并不能降低基金支付风险,根本原因在于“长缴多得”的计发机制;退休年龄的延长确能降低基金的支付风险,“早缴费”、“长缴费”将是减少养老基金支付风险的重要举措,但需要辅之以最低缴费年限调整才能充分发挥延迟退休增收减支作用;同一退休年龄下,女性比男性获益程度更高,相应地对实现缴费与待遇平衡产生更大的负效应;缴费年限增加能够提高替代率,增强制度的保障功能;缴费比例降低以及退休后平均余命、城镇单位就业人员平均工资增长率、养老金增长率、个人账户记账利率以及平均缴费工资指数提高会增大基金支付风险。建议通过调整退休年龄辅之以最低缴费年限并进行参量调整以降低基金支付风险。     

重塑基本养老和企业年金之间关系

基本养老和企业年金之间的关系实质上是政府和市场的关系，目前，政府在养老保障体制的处理上存在相对重视基本养老而弱化企业年金制度建设的情况，导致基本养老制度在推进中存在缴费率过高、制度执行成本高、政府的财务持续性的问题：而另一方面，企业年金的发展空间受限，甚至沦入“富人俱乐部”的尴尬境地。在对上述问题做了剖析后，我们认为，中国的养老金制度应加快顶层设计，基本养老和企业年金制度建设应齐头并进，企业年金需要大力发展。     

重置成本法在幼龄林资产评估中的应用

重置成本法是资产评估中的基本方法之一,使用比较广泛。但是在幼龄林资产评估中该方法还存在诸多局限性,影响了幼龄林资产评估的准确性。针对幼龄林的特点,在使用重置成本法评估幼龄林资产时,必须参照当地平均水平的林分质量进行分析、修改和补充,从而使评估结果更加合理、准确。     

A discrete replacement model for a two-unit parallel system subject to failure rate interaction

In this paper, a repairable two-unit parallel system with failure rate interaction between units is studied. Failure rate interaction between units is described as follows. Unit-1 failure whenever occurs can increase the failure rate of unit-2 of some amount, while unit-2 failure can induce unit-1 into simultaneous failure. We consider a discrete replacement policy N based on the number of unit-1 failure. The system is replaced at the instant of the N-th failure of unit-1 or on simultaneous failure of the system. Our problem is to determine an optimal replacement policy N ^* such that the expected cost rate per unit time is minimized. The explicit expression of the expected cost rate per unit time is derived by introducing relative costs and the corresponding optimal number N* is also verified finite and unique under some specific conditions.     

图形创意之置换原理的运用

联想与想象为图形创意的两个方面，置换原理若在图形创意中运用得好，更易于表现和挖掘深层次、体现出耳目一新的视觉形象。本文主要阐述逻辑上的张冠李戴如何使图形产生了更深远的意义。     

农村养老保险综合替代率及其结构分析

中国农村养老保险进一步完善的难点之一是确定合理的养老金给付水平。衡量养老金给付水平最核心的指标是养老金替代率。采用"社会平均替代率"概念,提出养老金目标替代率设为农民劳均收入的50%能够实现"保基本"的目标。现行农村社会养老金替代率约为8%,远低于目标替代率水平,农村养老保险体系中的土地保障、子女养老、社会救助发挥了重要作用,农民养老综合替代率达到32%~37%。未来随着社会养老金给付提高,综合替代率将在2030~2035年达到目标替代率水平,在2050年达到66%~68%。农村养老保险体系从以家庭养老为主向社会养老为主转变。