Research Progress of the Planning Methods of Prior Conservation Areas

The planning of prior conservation areas is an important part of nature re- serve system, ：it is of great significance for biodiversity conservation. The methods of priority planning include hot-spots analysis, gap analysis, systematic conservation planning analysis and multi-criteria decision analysis. The key issues of priority area planning include the determination of the protect objects, the analyses of the protec- tion value and protection cost, the win-win development of protection and economy, and the changes of the management strategies of the protected areas. In this study, the features and research progress of different conservation methods were analyzed, and based on the discussion on the key issues of the planning of the protected areas, the application prospect of different methods was analyzed.

Differences and relations of objectives, constraints, and decision parameters in the optimization of individual heat exchangers and thermal systems

Performance improvement of heat exchangers and the corresponding thermal systems benefits energy conservation, which is a multi-parameters, multi-objectives and multi-levels optimization problem. However, the optimized results of heat exchangers with improper decision parameters or objectives do not contribute and even against thermal system performance improvement. After deducing the inherent overall relations between the decision parameters and designing requirements for a typical heat exchanger network and by applying the Lagrange multiplier method, several different optimization equation sets are derived, the solutions of which offer the optimal decision parameters corresponding to different specific optimization objectives, respectively. Comparison of the optimized results clarifies that it should take the whole system, rather than individual heat exchangers, into account to optimize the fluid heat capacity rates and the heat transfer areas to minimize the total heat transfer area, the total heat capacity rate or the total entropy generation rate, while increasing the heat transfer coefficients of individual heat exchangers with different given heat capacity rates benefits the system performance. Besides, different objectives result in different optimization results due to their different intentions, and thus the optimization objectives should be chosen reasonably based on practical applications, where the inherent overall physical constraints of decision parameters are necessary and essential to be built in advance.