改革开放以来我国适度消费率的实证研究

当前我国最终消费率低于适度消费率下限,我国消费率水平明显偏低,依靠扩大消费需求拉动经济增长的效果仍不明显。为此,我国需要积极制定中长期政策,鼓励和促进居民消费;适度控制投资规模,改变大量依靠政府投资拉动经济增长的模式;缩小收入差距,提高居民收入水平;进一步完善社会保障体系,继续深化相关配套改革。

热能循环式热风滚筒杀青机的设计与仿真

为实现大宗绿茶的大批量机械化生产,解决杀青过程中茶叶红梗焦叶、含水量偏高以及热能利用率低的问题,设计了一款热能循环式热风滚筒杀青机,主要包括传动机构、螺旋输送式双通道喂料斗和杀青筒上部风道结构。利用Fluent软件对杀青滚筒内风的温度场进行仿真模拟对比分析,得出设有进风结构更佳的结论。利用EDEM软件对滚筒转速、茶叶喂入速率和滚筒温度进行单因素的数值模拟仿真分析,以确定机器最佳工作参数区间。在最佳工作参数区间确定后,进行三因素三水平样机试验,并运用Design-Expert数据分析软件得出杀青叶适度率与各因素的回归方程,进行显著性分析和响应面分析。结果表明:各因素间存在交互作用,三因素对杀青叶适度率影响显著程度为滚筒转速>喂入速率>滚筒温度;当滚筒转速为19r/min、茶叶喂入速率为17kg/min、滚筒温度为299℃时,杀青叶适度率为96.32%,杀青叶品质较优,样机验证试验结果与软件分析结果一致。

建筑振动舒适度设计的抗力模型

根据烦恼率计算模型和振动舒适度标准,给出了适用于不同使用场合下普通建筑物的振动烦恼率曲线,进一步从简单的人数统计原则出发,讨论了随机振动强度下烦恼率期望值的计算方法,通过与传统结构可靠度计算方法进行比较,说明了烦恼率期望值本身就是一种失效概率,烦恼率期望值的计算与结构失效概率的计算完全等同,因此,可以把烦恼率曲线看成一种新的抗力模型,按照结构可靠度的分析方法分析振动舒适度问题.

农业保险供求与适度保费补贴率的确定

本文基于一定的假设条件,运用经济学供求理论,采用投保率水平度量农业保险的政策目标,建立了农业保险适度保费补贴率决定模型,揭示了适度保费补贴率变动的一般规律。基本结论是:在一定的农业保险政策目标条件下,适度保费补贴率决定于农业保险的公平精算费率与无补贴情况下农户的需求状况;适度保费补贴率随农业保险发展阶段的不同而不同,即随农业保险供求状况的变动而变动,其一般规律是从低到高,再从高到低的实现过程,因而应适时调整保费补贴政策。

基于消费水平稳定的养老金适度缴费率研究

近期劳动和社会保障部对养老保险缴费率进行了调整,这能在一定程度上缓解基础养老金收支失衡的压力,同时也为做实个人账户创造了前提条件。理论分析表明,调整后的缴费率仍有改进的余地。如果将个人适度缴费率高出制度缴费率的部分转移到基础养老金中,则会大大充实基础养老金的收入,并且在可预见的未来使养老金收支赤字的局面得到根本改善。

城镇职工医保适度缴费率确定的动态模型及“十三五”期间现有缴费率降低测算

目的:研究城镇职工医保适度缴费率确定的动态模型及对"十三五"期间降低现有缴费率进行测算。方法:构建数理模型对研究对象进行研究。结果:有8个参数共同决定城镇职工基本医疗保险适度缴费率。结论:"十三五"期间,如果保持现有统账结合的财务制度不变,城镇职工基本医疗保险可以把缴费率由8%降低为7.9%。如果取消城镇职工基本医疗保险个人账户,城镇职工基本医疗保险可以把缴费率由8%降低为7%。

Elimination Mechanism and Equilibrium Model about Complete Linkage of Panmixis Based on Fitness

[Objective]The aim was to discuss elimination mechanism and equilibrium model about complete linkage gene of panmixis based on fitness.[Method]A mathematical model that gsgenerational evalution of frequency of panmixis two pairs of complete linkage gene under difference fitness was built by using difference equations to study elimination mechanism and genetic equilibrium state of panncticcoinplete linkage gene.[Result]The panmixis is different from Hardy-Weinberg Equilibrium which reached the equilibrium just by one generation.A method that by using linear equation to calculate the frequency of four gametes and the fitnessed of panmixis was established after detormining is the fitness of 10 genotypes the necessary and sufficient condition of the panmixis to reach balance.[Conclusion]The method is valuable for reference on linkage disequilibrium and hitchhiking effect study.

城乡居民基本养老需求、调整机制与城镇化水平

中国城乡居民基本养老保险制度虽然取得了较大成效,但距离真正满足居民养老需求还存在待完善的空间。本文运用ELES模型对城乡居民基本养老需求水平进行定量分析,划分了需求的上、下限,得到测算期(2002—2015年)的城乡居民养老需求替代率;且基于替代率,设计了居民养老金城乡统筹的三种方案:分别是"双下限"方案、"城下农上"方案和"双上限"方案;之后通过柯布—道格拉斯型调整函数,得出三种方案下的物价与收入指数权重,并基于该结论对2018—2050年城乡居民养老需求进行了预测;最后结合城镇化率,测算了不同城镇化发展阶段所适用的养老金给付标准。

An Improved Design of Spiral Groove Mechanical Seal

The coupling effect among the flow of fluid film, the frictional heat of fluid film and the thermal deformation of sealing rings is inherent in mechanical seals. The frictional heat transfer analysis was carded out to optimize the geometrical parameters of the sealing rings, such as the length, the inner radius and the outer radius. The geometrical parameters of spiral grooves, such as the spiral angle, the end radius, the groove depth, the ratio of the groove width to the weir width and the number of the grooves, were optimized by regarding the maximum bearing force of fluid film as the optimization objective with the coupling effect considered. The depth of spiral groove was designed to gradually increase from the end radius of spiral groove to the outer radius of end face in order to decrease the weakening effect of thermal deformation on the hydrodynamic effect of spiral grooves. The end faces of sealing rings were machined to form a divergent gap at inner radius, and a parallel gap will form to reduce the leakage rate when the thermal deformation takes place. The improved spiral groove mechanical seal possesses good heat transfer performance and sealing ability.

Evolution of two properties for scale-free network

Fitness of node can denote its competing power and clustering denotes the transitivity of network. Because the fitness of node is uncertain or fuzzy in some social networks, an explicit form of the degree distribution on fuzzy fitness is derived within a mean field approach. It is a weighted sum of different fuzzy fitness. It can be found that the fuzzy fitness of nodes may lead to multiscaling. Moreover, the clustering coefficient of node decays as power law and clustering coefficient of network behavior not-decrease-but-increase’ phenomenon after some time. Some computer simulation results of these models illustrate these analytical results.

Biological Effects in Heterotic Combination with Novel Adaxially-rolling Character in Rice(Oryza sativa L.)

Taking the heterotic combinations which respectively had moderately-rolled leaves and flat leaves at middle and later stages as tested materials, the biological effects in the heterotic combination of the moderately-roiling leaf mutant RL（f） were studied. The results showed that （i） there was insignificant difference between the leaf morphological characteristics of the RL（t） and fiat leaf heterotic ombinations at early growth stage in that beth of them had fiat leaves and relatively big basic leaf angles; （it） the stomatal conductance, the intercellular CO2 concentration, transpira- tion rate and photosynthetic rate of the three top leaves of the RL（t） heterotic com- bination were significantly higher than those of the flat leaf heterotic combination at middle and later stages, which laid the foundation for increasing the yield per unit area; （iii） the light transmittance of the RL（f） heterotic combination in population at the middle part was higher than that of flat leaf heterotic combination, resulted in improved light interception condition at middle and lower parts of the population and increased the utilization efficiency of tight energy; and （iv） this research revealed that the RL（t） heterotic combination could not only maintain a larger amount of the effective panicles but also could present large-panicle characteristic, especially in high-density condition, and also the ability of adjusting yield components the RL（f） heterotic combination was significantly increased under different densities. This study would provide a theoretical basis for the principle of high-yielding breeding with the application of the moderately-rolling leaf mutant in rice.

Joint adaptive waveform and baseline range design for bistatic radar

The problems of joint adaptive waveform design and baseline range design for bistatic radar to maximize the practical radar resolution were considered.Distinguishing from the conventional ambiguity function(AF)-based resolution which is only related with the transmitted waveform and bistatic geometry and could be regarded as the potential resolution of a bistatic radar system,the practical resolution involves the effect of waveform,signal-to-noise ratio(SNR)as well as the measurement model.Thus,it is more practical and will have further significant application in target detection and tracking.The constraint optimization procedure of joint adaptive waveform design and baseline range design for maximizing the practical resolution of bistatic radar system under dynamic target scenario was devised.Simulation results show that the range and velocity resolution are enhanced according to the adaptive waveform and bistatic radar configuration.

Assessment and Guidelines to Improve Eco-efficiency and Indoor Comfort at University of Passo Fundo, Brazil

The paper deals with the energy and indoor comfort on buildings of UPF （University ofPasso Fundo）, located in southern Brazil, in order to improve the eco-efficiency concepts in the university＇s building stock, reinforcing its responsibility towards sustainable development. The factors that affect thermal performance and the energy consumption of two case studies were identified, including the general characteristics of the envelope and the indoor conditions. The simulations with DesignBuilder software compare the energy and thermal performance of both cases： those results allow the identification of their positive and negative aspects, as well as making a co-relation with the students＇ sensations of comfort--obtained through PMV （predicted mean vote）. The research indicates that it will be possible to improve eco-efficiency of existing and new buildings and campuses by retrofitting and upgrading it with regard to better indoor conditions that really correspond to climate conditions （hot and humid summers, and cold and damp winters）, using passive strategies for heating and cooling and at the same time to improve rational use of natural resources and to reduce the environmental impact. Probably, giving comfortable conditions to the users will increase energy consumption, but there is a potential reduction of lighting and equipment that could minimize this impact.

The Study of Thermal Mass as a Passive Design Technique for Building Comfort and Energy Efficiency

The day/night （diurnal） changes in temperature and solar radiation pose challenges for maintaining human thermal comfort in buildings. Passive and energy-conserving buildings seek to manage the available thermal energy by lowering peaks and dampening the fluctuations in order to maintain conditions for human comfort. Appropriate use of thermal mass moderates the internal temperatures by averaging diurnal extremes. Thermal mass is one of the powerful tools which architects and designers can use to control temperature. It can be used to optimize the performance of energy-conserving buildings that rely primarily on mechanical heating and cooling strategies. Massive building envelopes-such as masonry, concrete, earth, and insulating concrete forms （ICFs） can be utilized as one of the simplest ways of reducing building heating and cooling loads. This article analyses the role and effectiveness of thermal mass as a strategy for providing indoor thermal comfort for passive solar and energy conserving buildings.

Coal mine safety production forewarning based on improved BP neural network

Firstly, the early warning index system of coal mine safety production was given from four aspects as per- sonnel, environment, equipment and management. Then, improvement measures which are additional momentum method, adaptive learning rate, particle swarm optimization algorithm, variable weight method and asynchronous learning factor, are used to optimize BP neural network models. Further, the models are applied to a comparative study on coal mine safety warning instance. Results show that the identification precision of MPSO-BP network model is higher than GBP and PSO-BP model, and MPSO- BP model can not only effectively reduce the possibility of the network falling into a local minimum point, but also has fast convergence and high precision, which will provide the scientific basis for the forewarnin~ management of coal mine safetv production.

Is Larger Scale Better? Evidence from Rice Farming in Jianghan Plain

Small-scale household agricultural production has been in conflict with China＇s agricultural modernization.In the context of vigorously promoting rural land circulation and moderate scale management nationwide,research on the relationship between farm size and scale efficiency has become increasingly important.In this paper,we use the ＂DEA-OLS＂ two stage method to analyze data from 368 surveys of rice farming households in the Jianghan Plain.The scale efficiency of rice farming was calculated,and the relationship between farm size and scale efficiency investigated.The results indicate that（1） the rice farm size is generally small in Jianghan Plain,with an average of 0.77 ha.The average scale efficiency is 0.88,and it is the main factor limiting an increase in comprehensive technical efficiency.Moreover,88.32% of households are in the stage of increasing returns to scale.（2） There is a stable inverted ＂U＂ type relationship between rice farm size and scale efficiency.Considering characteristics of the householder,the household and land quality,the maximum scale efficiency corresponds to a household with 5 ha of rice farm.（3） Among householder characteristics,age has a significant negative influence on scale efficiency,and scale efficiency is lower for a household whose householder is engaged in non-farm work than for one whose householder is devoted to farming.As for land quality,there was a significant positive effect of irrigation on scale efficiency.Among family characteristics,the application of a machine during the seeding process increased scale efficiency by 3.07%.Therefore,we suggest that local government should actively promote rural land circulation,implement a staged-scale management subsidy,and other forms of support for the purchase of agricultural machinery and technical popularization.Increased investment in irrigation improvements and mechanical facilities and encouragement of farmers to enlarge their farm size could improve scale efficiency and farming profit and lead to the development of moderate scale management.

Optical Properties of Laterally Aligned Si Nanowires for Transparent Electronics Applications

We have investigated the optical properties of laterally aligned Si nanowire （SiNW） arrays in order to explore their potential applicability in transparent electronics. The SiNW array exhibited good optical transparency in the visible spectral range with a transmittance of -90% for a NW density of -20-25 per 10 μm. In addition, polarization-dependent measurements revealed a variation in transmittance in the range of 80%-95% depending on the angle between the polarization of incident light and the NW axis. Using the SiNWs, we demonstrated that transparent transistors exhibit good optical transparency （greater than 80%） and showed typical p-type SiNW transistor characteristics.