一种镀锌板生产线电气传动控制系统

介绍了镀锌板生产线的工艺流程及其对电气传动的要求，采用PLC对镀锌板生产线的张力和带速进行协调控制，对电气传动控制系统的活套带重补偿和控制算法作了论述。本系统在实际使用中可靠性高，经济效益好，是一种适用的镀锌板生产线电气传动控制系统。     

基于GASA算法的提前或拖期问题优化

针对企业生产的提前 /拖期问题,提出了提前 /拖期问题的数学模型,在此基础上,利用GASA混合优化策略优化之,既保留了传统遗传算法能很快达到最优值领域的优点,又通过结合模拟退火算法大大改善传统遗传算法在后期的收敛性。     

风险投资与孵化器结合初探

建立孵化器，是促进科技成果转化、培育科技型中小企业的有效途径,是被实践证明了的加速高新技术产业化的重要经验，也是建设国家创新体系的重要组成部分。对孵化器和风险投资结合的初步研究，可以更好地把两相融合，更好地培育科技型中小企业，从而加速高新技术产业化进程。     

美国金融业对外直接投资流向的实证分析

美国1995年～2000年金融业对外直接投资流向分布极不均衡,对投资流向分布进行统计分析发现,非金融领域直接投资、1994年金融业对外直接投资存量、双边贸易量、东道国经济金融发展水平是金融业对外直接投资的主要决定因素,证明了邓宁国际生产折衷主义理论对金融业对外直接投资的解释力。据此简要分析美国对中国金融领域直接投资现状,并分析了今后发展趋势。     

Wood Fuel or Carbon Sink? Aspects of Forestry in the Climate Question

This paper discusses and contrasts two mainroles of forestry in light of the debate on theglobal climate. As the main problem is relatedto the increases of the CO₂-concentrationin the atmosphere, forests may be viewed aspart of the alleviation of the problem throughtheir function as (i) a source of biomass forenergy production, which may replace fossilfuels and thus indirectly reduceCO₂-emissions, and as (ii) carbon storage,since a growing forest extracts atmosphericCO₂ and fixes it as carbon in biomass. Inthe Scandinavian forestry, logging residues areincreasingly being used for energy production.In this paper the value of forests as a sourceof bioenergy is added to the traditional timbervalue. Formulated as a joint production modelwithin the Faustmann framework, the effect ofthis addition on the optimal rotation length isdiscussed. Based on data for spruce, thedominant species in the Scandinavian forestry,it is demonstrated that the rotation length isshortened compared to the standard Faustmannmodel. Shorter rotation length implies lesscarbon storage. Therefore, in this modelwithout explicit regard to the social carbonstorage value of the forest, the gains in termsof the climate problem from utilisation offorest biomass for energy production are beingdiminished by the value of reduced carbonstorage. The carbon value of the forest is thenadded to complete the model, with the effect ofincreasing the rotation length, a result thatis well known in the literature. Finally, theempirical effects of the interaction of thesetwo climate-related value elements of theforest are discussed.     

退耕还林（草）生态补偿实施现状与问题分析——以甘肃省定西市安定区为例

为了建立合理的国家生态补偿机制，了解现阶段生态补偿中存在的问题，我们运用PRA（Participatory rule appraisal）即参与性农村评估和传统的问卷调查相结合的方法，通过对研究区内生态建设补偿措施实施过程中的现状研究、问题分析，发现本区在实施退耕还林（草）生态补偿中的主要问题是仍然没有有效解决生态补偿的三个基本问题：补偿主体、补偿强度、补偿资金来源。生态补偿处于初级阶段，没有形成制度化、法律化，有必要在政策、法律层面建立比较完善的生态补偿机制。     

先进制造技术与生产流程的协同性研究

制造系统的有效性需要通过先进制造技术与生产流程的合理匹配来体现。在分析各种先进制造技术与生产流程相互关系的基础上,提出了协同度的概念,并给出了其计算方法。     

Study on the planning principles of urban forest

The urban forest is the main body for the urban forestry management. There are not unified rules and standards for the planning of the urban forest yet in China. This paper discusses the planning principles of the urban forest： the priority of the ecological function, the adaptation to local condilions, the optimization in the whole system, the mutual dependence of forest and city, the culturecontinuance and recreation satisfaction, sustainable development and operability, etc. This paper takes Changsha as an example to elaborate the planning principles of the urban forest. Firstly, Changsba urban forest ecosphere is composed of the eco-garden, the round-the-city forest belt, the ecological isolation belt, the green channel, the landscape of the rivers and streams, the forest park, the biodiversity reserve and the eco-forest in suburb area. It aims to make every kind of ecological essential factors organically merge into the complex city ecosystem to build an eco-city, to strengthen the connection of wide-open space with various habitats spots, to promote resident＇s accessibility, to perfect landscape ecology, and to make full use of the ecological function of urban forest. When we construct the urban forest, we must optimize the comprehensive benefit and make the urban forest structure and the layout in the best condition in order to buiM the harmonious green city for both man and nature to realize the whole optimization of the city system by the complex functions of the urban forest in ecology, environmental protection, landscape, recreation, etc.     

试析森林生态环境价值计量研究中的几种干扰因素

本文就目前影响在林生态环境价值计量研究的几个干扰因素进行剖析。其中主要包括森林生态环境难以进入市场的原因；在林生态环境资源并不是都重要计量；森林生态环境的价值既是哲学的价值也是经济学上的价值；森林的生态环境转移与它的价值转移没有实现统一；森林生态环境价值计量使用的概念需要明确和统一；在林生态环境资源的监测和统计；影子价格理论在森林生态环境价值计量中应用的合理性；森林生态环境资源生产的投入产出进行过程等问题。这些问题如果得到及时解决，将有助于在林生态环境计量的进一步研究。     

湖南森林旅游开发与森林公园保护

“回归大自然,走进大森林”是当今世界旅游业的新时尚,也预示了湖南省未来森林旅游的良好前景,本文阐述了湖南省开展森林旅游的资源条件和森林公园的发展概况,探讨了森林公园旅游开发的指导思想、原则、目标、重点和对策,并针对森林公园在旅游开发过程中存在的问题,提出了保护的具体措施。