玉石的新品种──恰拉玉

本文介绍玉石家族新品种──俄罗斯伊尔库斯克的特产恰拉玉。文中讨论了恰拉玉的命名、宝石地质学、宝石矿物学、鉴定特征及工艺验等。     

基于边缘层活动的战略决策模式

安东尼—安索夫—安德鲁斯范式确定了经典的战略决策模式，高层管理者成为战略决策的权力中心、信息中心与知识中心，处于公司边缘层的员工行为对战略决策的影响常常被忽视。欧洲研究者提出“活动基础观”这一新的战略范式，边缘层行为对公司战略决策的重要意义日益受到重视。边缘层行为是市场导向的、反复试错的结果，公司总部常常在与边缘层的相互冲突、相互学习中发现新战略。     

全球价值链下中国增加值贸易的核算及网络特征研究

基于投入产出模型和社会网络分析，利用世界投入产出表相关数据，对2000—2014年中国的增加值贸易进行核算，并分析全球增加值贸易的网络特征。研究结果显示：（1）从出口目的地来看，中国向美国、日本、德国等国家的增加值出口较大；（2）从行业来看，中国的纺织业、除汽车和摩托车之外的其他产品批发业、采矿业等行业的增加值出口较大；（3）根据网络密度的计算结果，世界范围的各国（地区）贸易联系程度在增强；（4）中国的相对点度数和点强度有上升的趋势，而日本和美国有下降的趋势，说明中国在世界增加值贸易格局中的地位在提升，不过美国仍在世界增加值贸易格局中占据主导地位；（5）核心边缘分析结果表明核心国家（地区）的数目经历了先增加后减少的过程，边缘国家（地区）数目则先减少后增加。其中，中国的核心度一直在增加，日本和美国的核心度呈现下降的趋势。因此，为了扩大增加值贸易，增强国际贸易的话语权，中国政府有必要采取调整进出口税率等政策，并重视与美国等国家的双边贸易合作，以实现双赢的结果。     

The economics of the super‐multiplier: A comprehensive treatment with labor markets

This paper links the super‐multiplier to Keynesian macroeconomics, showing it to be the most Keynesian of growth perspectives. Next, the paper shows that the super‐multiplier is a micro‐economically coherent theory of investment and capital accumulation. Firms’ decisions regarding capital accumulation coordinate demand and supply growth in goods markets. The paper then explores the implications of incorporating the super‐multiplier in the neo‐Kaleckian and Cambridge growth models. Lastly, it shows how labor markets and unemployment can be added into super‐multiplier models to provide a comprehensive growth model that addresses Solow's (1956, Journal of Economics, 70, 65–94) labor market knife‐edge problem. Incorporating labor markets does not change the fundamental super‐multiplier result that growth is determined by the growth of autonomous demand.     

基于小波变换的图像处理综述

小波分析主要广泛应用在科学研究和工程技术中。虽然在现阶段的小波理论相对成熟,近些年关于小波理论的应用和研究也在不断的发展和更新。小波变化在图像处理领域中的应用也囊括图像与处理的所有方面。本文通过介绍小波变换的起源,将小波应用在图像处理中的压缩、还原图像、边缘检测和图像分割,宏观剖析小波的研究现状历史、发展动向及优势。     

平铝压条碾压装置的设计分析

为解决车用平铝压条生产效率低,装配困难的问题,本文设计了一套平铝压条碾压装置,阐述了该装置的结构布置及工作原理。经使用验证,该装置结构简单,易操作,同时提高了平铝压条装配工艺水平,降低了工人的劳动强度。     

Building from Scratch: New Cities,Privatized Urbanism and the Spatial Restructuring of Johannesburg after Apartheid

By the start of the twenty‐first century, the once dominant historical downtown core of Johannesburg had lost its privileged status as the center of business and commercial activities, the metropolitan landscape having been restructured into an assemblage of sprawling, rival edge cities. Real estate developers have recently unveiled ambitious plans to build two completely new cities from scratch: Waterfall City and Lanseria Airport City (formerly called Cradle City) are master‐planned, holistically designed ‘satellite cities’ built on vacant land. While incorporating features found in earlier city‐building efforts, these two new self‐contained, privately‐managed cities operate outside the administrative reach of public authority and thus exemplify the global trend toward privatized urbanism. Waterfall City, located on land that has been owned by the same extended family for nearly 100 years, is spearheaded by a single corporate entity. Lanseria Airport City/Cradle City is a planned ‘aerotropolis’ surrounding the existing Lanseria airport at the northwest corner of the Johannesburg metropole. These two new private cities differ from earlier large‐scale urban projects because everything from basic infrastructure (including utilities, sewerage, and the installation and maintenance of roadways), landscaping, security services, the regulation of common spaces, and selling and branding the city are firmly in the hands of private profit‐making corporate entities and outside the mandate of public authorities.     

Forecasting in a Mixed Up World: Nowcasting Hawaii Tourism

We evaluate the short term forecasting performance of methods that systematically incorporate high frequency information via covariates. Our study provides a thorough introduction of these methods to the tourism literature. We highlight the distinguishing features and limitations of each tool and evaluate their forecasting performance in two tourism-specific applications. The first uses monthly indicators to predict quarterly tourist arrivals to Hawaii; the second predicts quarterly labor income in the accommodations and food services sector. Our results indicate that compared to the exclusive use of low frequency aggregates, including timely intra-period data in the forecasting process results in significant gains in predictive accuracy. Anticipating growing popularity of these techniques among empirical analysts, we present practical implementation guidelines to facilitate their adoption.     

浅析数控曲轴连杆轴颈车床夹具设计的有效改进

数控曲轴连杆颈车床用来加工一般四拐曲轴的连杆颈,该夹具已使用多年,但随着近年来新产品开发数量的增多,已远不能满足使用要求,本文就CF-702数控曲轴连杆轴颈车床的夹具设计,进行有效的改进,具有一定的参考价值。     

战后美国城市发展的新特点

"二战"后,美国城市发展从原来的传统城市化,转入大规模的人口郊区化,郊区"卧城"大量产生.20世纪80年代以来,美国进入"后工业"社会城市发展时期,产生了"边缘城市"与"无边缘城市"等城市空间新类型,同时也面临资源、居住和社会经济等方面的问题.