比值评价 给力促学

比值评价法是一种新型的评价方式，它强调的是个人与个人比、现在和过去比，不仅评价学生，也同时可以评价老师。这种评价法在国内、国外都没有明确的操作方法可供参考，是一种新型的评价方式，需要进行积极的实践探索，也有待在实践中检验和完善。

Symmetry Reduction of Initial-Value Problems for a Class of Third-order Evolution Equations

Symmetry reduction of a class of third-order evolution equations that admit certain generalized conditionalsymmetries (GCSs) is implemented.The reducibility of the initial-value problem for an evolution equation to a Cauchyproblem for a system of ordinary differential equations (ODEs) is characterized via the GCS and its Lie symmetry.Complete classification theorems are obtained and some examples are taken to show the main reduction procedure.

Sustainability of Urban Lakes： Role of Values in Lake Governance in Ahmedabad, India

Lakes have different social, economical, and ecological values at different periods of societal development, which make them vulnerable to change. One of the ongoing discussions in urban lake governance in India is the revitalization of the urban lakes. The core challenge documented in the governance of urban lakes is to address and find balance in the changing and competing value systems. Effectively addressing the change （or priority） in the values linked to the governance systems is a major step toward sustainability of the urban lakes. There is still limited understanding of how the values of urban lakes are progressively linked to the social, ecological and economic values of the urban developments. The paper looks at the interactions and outcomes of the spatial and temporal dynamics of the urban lakes systems especially the values that sustain the institutional and ecological memory. The focus is on the role of values in urban lake governance. The multitier framework for analyzing social-ecological systems CSES） which is in developmental phase at Elinor Ostrom＇s Workshop is used as the guiding framework to build understanding of the urban lake governance in Ahmedabad, India and at the same time contribute to the development of the SES framework.

Development Trends and Evaluation of Egbe Reservoir Water Nutrient Status in Ekiti State, Nigeria

A study about some physicochemical parameters of Egbe reservoir was carried out from September 2005 to December 2006. The parameters include mean temperature, pH, conductivity, alkalinity, TSS, TDS, DO and BOD which have values of 28.7±0.9 ℃ ; 8.3±0.3; 831±172.5 μS/cm; 165.4±18.3 mg/L; 0.06±0.1 mg/L; 0.4±0.6 mg/L; 7.8±2.4 mg/L and 5.2±1.6mg/L, respectively. Temperature and pH were measured in the field using mercury-in-glass thermometer calibrated in degrees Celsius and pH meter, respectively. TSS and TDS were measured by grayimetric methods, while alkalinity was measured titrimetrically and DO and BOD were measured by Winkler＇s method. For the nutrients, nitrate was measured color±metrically, phosphate by Stannous Chloride method and sulphate by turbidimetric method. Mean concentration of nitrate, phosphate, and sulphate were 15.6±8.6 rag/L; 42.5±19.4 mg/L and 72.3±14.7 mg/L respectively. Nowadays, eutrophication of natural waters is one of the most significant causes of deterioration of water quality, and nitrates and phosphates are probably the key nutrients in controlling the growth of aquatic plants. Though the mean concentration of nitrates and phosphates in the reservoir water were within the acceptable limit, yet their concentrations in some locations of reservoir were high enough to encourage the growth of aquatic macrophytes which would increase productivities. Hence, it is necessary to check their further increase, and periodic monitoring and preventive measures must be adopted to save the reservoir from eutrophication.

A Factor Analysis of the Tourism in the Mexican Province of Michoacan

The tourism is a key branch in the world wide economy nowadays, and revenues account for one third of total income in the world. Many nations are trying to improve their tourism sector attracting more tourists every year in order to impact social welfare. This study addresses two research questions： （1） What are the factors that impact on tourism sector？ and （2） Does the tourism really impact on social welfare of the communities？ The objectives of this work are to analyze the variables that impact on the tourism in the Mexican providence of Michoacan and also to find out if the tourism sector is impacting on social welfare of the province, with the propose of answering this questions 41 variables were selected being 63 municipalities of Michoacan province in the case of study. Analysis Factorial of Correspondences （AFC） through the analysis of principal components methodology is employed in this article. The analysis is divided into five phases： （1） reliability testing; （2） the calculation of a matrix that expresses the joint variability of the variables; （3） extraction of the optimal number of factors; （4） the rotation of solutions for the ease of interpretation; and （5） the estimation of the scores graphically. The results showed that the variables that impact on tourism are several the most representative tourism infrastructure and complementary services restaurants, lodging with category five- and four- star travel, visitors foreign share of the Economic Active Population （EAP） in the tertiary sector, percentage of EAP women, percentage of economically active men and Gross Domestic Product （GDP） per capita among others. However the analysis of the Human Development Index （HDI） is not associated with the tourism variables

Research on the Sustainability of Afghanistan Based on the Emergy Analysis

Afghanistan is an important country for the Silk Road Economic Belt and the 21 st Century Maritime Silk Road（the Belt and Road） proposed by China. Due to years of war,Afghanistan is not well-developed economically. However,Afghanistan has abundant mineral resources and unique geographical advantages that are of far-reaching significance for Chinese economic strategic development. To investigate the sustainability of the eco-economic system of Afghanistan,we completed a quantitative evaluation of the emergy of Afghanistan during the period 2008 to 2015 by establishing an indicator system based on an emergy analysis. Results showed that from 2008 to 2015,the total emergy used of Afghanistan increased from 5.56×10^（22） sej to 9.75×10^（22） sej,among which the proportion of non-renewable emergy was less than 25.7%. This indicates that local resources in Afghanistan have yet to be exploited and utilized effectively and that its economic development relied heavily on the input of external resources. Meanwhile,the Emergy Sustainability Index（ESI） of Afghanistan from 2008 to 2015 dropped from 3.00 to 0.72,the Environmental Loading Ratio（ELR） increased from 0.77 to 2.06,and the Emergy Yield Ratio（EYR） dropped from 2.31 to 1.49,reflecting the imbalanced utilization of resources and the low level of economic development in Afghanistan. As a result,the potential for sustainable development of Afghanistan is relatively great. Basic infrastructure construction and reasonable exploitation of natural resources are the urgent needs.