大学生暑期社会实践创新模式探析——以成都理工大学为例

当前大学生暑期社会实践活动还存在着实践活动与所学专业结合不够紧密,实践活动流于形式,走过场现象较为严重。实践活动在形式和内容上针对性、实效性较差,实践活动重“精英”．轻普及,实践活动“运动模式”的缺陷等问题。直接影响到社会实践活动自我教育和服务社会目的的实现。成都理工大学通过多年的积极探索和丰富的实践经验积累,摸索总结出了一套较为有效的大学生暑期社会实践创新模式．即坚持“专业依托”、“广泛参与”、“长效机制”三项原则。运用“基层调研”、“志愿服务”、“素质拓展”三种形式和采取“结合课题”、“双向宣讲”、“项目化管理”三种方法的“三个三”运作模式。     

Simple and inertial behavior: an optimizing decision model with imprecise perceptions

Summary Simplicity and inertial (or status-quo) bias are common features of actual decision rules used by real-life agents. In this paper, we provide one possible rationale for these features in terms of a model in which the decision maker is subject to imprecise perceptions about the consequences of actions that differ from (an already experienced) status quo.I am grateful to participants in seminars at Harvard University, University of Virginia, Virginia Polytechnic Institute, and Universitat Autonoma de Barcelona for helpful comments. Finantial support by the CICYT, project no. PB86-0613, and the Institute for Advanced Studies of the Hebrew University of Jerusalem in gratefully acknowledged.     

The Polish Experience in Bank and Enterprise Restructuring

MOCT-MOST: Economic Policy in Transitional Economies -     

Low carbon procurement: An emerging agenda

The importance of climate change is shaping public policy internationally at several levels with much of the effort aimed at reducing the amount of carbon emissions released to the atmosphere through anthropogenic activity. Public procurement is a key financial mechanism available to governments to drive policy change and because of its scale can be also one of the most effective. During the past decade Low Carbon Procurement (LCP) has emerged as focal policy agenda in the UK and other countries. However, the implementation of LCP requires improved definition by governments and a greater understanding of Carbon Management tools and concepts such as Lifecycle Analysis on the part of procurement chiefs. Focusing on public procurement in the UK within the context of international policy development, this paper develops a working definition and model for LCP to guide future discussions on policy and practice. The paper presents an agenda of expected challenges for the implementation of LCP, including problems associated with weighing trade-offs between carbon and wider environmental or sustainability objectives, use of carbon tools and methodologies. The paper concludes by identifying key directions for further LCP research.     

U-Convolutional model for spatio-temporal wind speed forecasting

The increasing penetration of intermittent renewable energy in power systems brings operational challenges. One way of supporting them is by enhancing the predictability of renewables through accurate forecasting. Convolutional Neural Networks (Convnets) provide a successful technique for processing space-structured multi-dimensional data. In our work, we propose the U-Convolutional model to predict hourly wind speeds for a single location using spatio-temporal data with multiple explanatory variables as an input. The U-Convolutional model is composed of a U-Net part, which synthesizes input information, and a Convnet part, which maps the synthesized data into a single-site wind prediction. We compare our approach with advanced Convnets, a fully connected neural network, and univariate models. We use time series from the Climate Forecast System Reanalysis as datasets and select temperature and u- and v-components of wind as explanatory variables. The proposed models are evaluated at multiple locations (totaling 181 target series) and multiple forecasting horizons. The results indicate that our proposal is promising for spatio-temporal wind speed prediction, with results that show competitive performance on both time horizons for all datasets.     

Technological change and path dependence: a co-evolutionary model on a directed graph

In this paper, I model technological change as an evolutionary process of generation and selection of economic activities in a highly path-dependent fashion. There are two key features of our approach. The first is that economic activities are conceived as points of a directed graph and endowed with a corresponding notion of technological distance which determines both the probability of invention of any new activity and the cost of learning it. The second feature is that agents are assumed rational and taken to choose optimally from among the available activities, given the status quo and the associated learning costs. In such a context, we focus on two economies that start off technologically close and evolve side by side with some extent of technological diffusion across them. It is shown that alternative assumptions on the speed of diffusion may have drastically different implications for the evolution of the process. I then argue that this theoretical analysis helps provide some insight on existing empirical evidence; in particular, on the conditions under which relative stagnation or technological catch-up may arise and become consolidated among different economies.     

醋酸丙酸纤维素的性质及应用

文章综述了醋酸丙酸纤维素的物理性能、化学性能、加工性能和溶解性能,以及醋酸丙酸纤维素在涂料、塑料和油墨等方面的应用。     

经济危机根源及其消除方法论

扫描人类活动,从中找到了公平、质效、GDP三个关键点。公平因素包括不公平分配和不公平交易,是引发经济危机的根本点。为实现公平,从土地切入发现了平衡工农城乡利益机制的投资置业系数CIP=(0,4]。这只能消除贫富悬殊引发的产消不畅之实体危机。为全面消除经济危机,应针对经济危机的六个阶段建设消除经济危机的系统工程。经济发展总是从公平到不公平,从公平、质效、GDP三者平衡到不平衡,最后进入经济危机状态;经济危机往往从金融危机开始,而我们应从土地切入调动资金作战。