Growth,development, and innovation: A look backward and forward

Papers in Regional Science - This article reviews where we have come from and where we are going in research on regional growth and development. Our object of study is the region, an imprecise term...     

Growth, development, and innovation: A look backward and forward

Abstract. This article reviews where we have come from and where we are going in research on regional growth and development. Our object of study is the region, an imprecise term that has been taken to mean areas as large as small countries or as small as urban regions, although how regions are defiend does itself have implications for both theories and the empirics of regional growth. How growth occurs remains a poorly understood process. Clearly the basic ingredients of the neo-classical cookbook are important – growth in capital and labour stocks with technological change – but they are neither enough nor revealing enough. Why does the stock of capital grow at different rates? Why does the labour supply increase? What drives technical progress? What are the roots of spatial dependence? We are fairly certain that the answers to these questions embrace agglomeration economies but they also embrace much more. Innovation is associated with research and development and has an identifiable spatial pattern in relation to highly skilled labour and institutions such as universities. But innovation is not just the result of R&D but also entrepreneurship applied to investment. Labour supply responds to real wage differentials but also to environmental and other amentities. Labour is far more geographically mobile in the New World, however, than it is in the Old.     

Visualization in the natural environment: a look forward

This paper discusses development of two alternative approaches, automated scaling and texture mapping, to the problem of merging the accuracy of the geometric database with the realism afforded by video-imagery. Both approaches provide the capacity for animation: movement within and through the simulated environment. We need however, to develop a better understanding of the significance of high-technology simulation.     

Disturbance of mining operations to a deep underground workshop

An underground workshop was located at a depth of 880 m in a metal mine, Sweden. A few years after its excavation, the workshop was subjected to a certain extent of damage. A number of fractures appeared on the walls of the workshop. Shotcrete separated from the rock surface and even fell down to the floor. The mine worried about what happened and wondered how the mining operations underneath would affect the workshop. A further question was if the workshop should be closed and a new one should be excavated. Those questions therefore concerned not only with the matter of safety but also of economy. An investigation of the instability in the workshop was conducted in 2000. It was carried out through geological surveys, in situ deformation measurements and also numerical modelling. The study revealed that the problem of instability in the workshop was associated with the mining operations at the level of the workshop even though the mine stopes were over 90-m away from the workshop. It was also assessed that the mining operations underneath would not disturb the workshop and thus the workshop could continue its service as usual. The mining operations underneath was finished in 2003. The results of a follow-up programme confirmed the assessments made in the study. Measurements of rock deformation showed that the workshop was stable during the whole period of mining underneath. Two lessons are learned from this case: (1) permanent underground infrastructures should not be placed in geological contact zones even if they are not necessarily weak zones; (2) the horizontal extent of the disturbance zone around an opening at depth can be very large. For the case in question, the horizontal stretch of the disturbance zone around the mine stope was approximately in the same order as the height of the stope.     

地下采矿条件下坡体移动变形分析

针对重庆武隆鸡尾山滑坡,结合地质分析,采用二维离散元方法(UDEC2D),分别建立了前缘崩塌体和后缘滑动体的简化二维数值模型,对地下开采作用下滑坡体前缘发生崩塌和后缘发生滑动失稳机制分别进行了研究,分析了地下开采作用对滑坡体前缘应力场和对滑坡体后缘位移场的影响。     

在结构调整中复苏--平板玻璃板块2003年回眸与2004年展望

一、2003年平板玻璃行业步入复苏阶段　　2003年受国民经济增长的拉动,特别是固定资产投资的高速增长,平板玻璃工业经济运行呈现出产销两旺、价格上涨、经济效益显著提高的特点。　　1、生产快速增长、需求旺盛　　2003年1～11月,全国累计生产平板玻璃2.27亿重箱,同比增长10%以上(图1);销量增长大于产量增长,10月末平板玻璃库存923.22万重量箱,同比下降13.84%。　　2、玻璃价格稳步上升,进入第三季度后增速加快　　2003年伴随着市场需求的不断增长,平板玻璃价格在非典之后开始持续攀升,4mm白色增长幅度最大,每重量箱由二季度末的50.63元…     

Improved prediction of differential subsidence caused by underground mining

Observations in the field demonstrate that there exist discrepancies between the differential movements predicted from theory and those experienced in practice. From the point of view of structural damage, such discrepancies should be eliminated in order to decrease subsidence damage associated with mining. Using non-linear geometrical field theory, the deformation factors are modified and the limitation of linear elastic theory is established. Only when the rotation angles are smaller than 4° is the application of conventional theory reasonable. A new deformation index, the mean rotation angle, is proposed. The study shows that there exists a relation between the mean rotation angle and the surface cracks. Incompatibility of rotation can initiate cracking. The outcome of the work presented will be helpful in improving the calculation accuracy of predicted differential movements, especially for steeper coal seam extraction, extraction under mountains, ‘top coal caving’ of thick seams, and mining in high relief areas.     

煤矿地下开采引发地面塌陷的危险性评估

以长春市双阳区长岭煤矿地质灾害危险性评估为例,介绍了煤矿采空引发地面塌陷危险性预测评估的基本内容及评估深度,并提出了较全面的矿区采空塌陷的防治措施,可以为矿井开采后防治地面塌陷提供指导。     

Automatic guidance of underground mining vehicles using laser sensors

Autonomous guided vehicles are becoming extremely important in the mining industry. The underground environment is unique and complex in that the lighting conditions are poor, the roads are difficult to traverse, and no GPS can accurately receive signals in these areas. This paper analyzes the characteristics of commonly used positioning methods given that ordinary positioning and navigation methods do not work effectively underground. We outline the composition and principles in underground guidance of autonomous vehicles using the laser-based positioning system. This system is unique in that it draws on the premise of barcode theory, which allows for a feasible relative navigation system even without a GPS. Algorithms were developed to provide real-time control for an autonomous guided scraper. In the vehicle experiment, the scraper was able to autonomously move along the simulated laneway, and the trial average range longitudinal error was only 15 cm in a 40-m distance. Hence, this new type of positioning and navigation system can accurately and reliably guide vehicles.     

地下开采对水利工程影响之研究

采用影响函数法对地下开采引起的上部岩体移动变形问题建立了数学模型,实践证明该数学计算模型可应用于计算地下开采引起的地表变形,并对河南某矿地下开采引起的上部地表水利工程设施安全性的影响进行了分析,分析表明,该地表变形量会使地表建筑水利设施的地基产生裂缝、变形及不均匀沉降,直接影响水利设施的质量和安全运营。     

Upshot of strata movement during underground mining of a thick coal seam below hilly terrain

Underpinning-based simultaneous extraction was successfully used to extract more than 90% of thick and contiguous sections of a coal seam at Chirimiri mine, lying below a hill cap with a rapid change in depth of cover and is placed above the surrounding ground level. The last few panels of the mine encountered strata control problems during the depillaring. Underground instrumentation and observations showed that the last phase depillaring of the property near the free surface of the hill slope experienced shearing of overlying strata along two incompetent layers. Field investigations revealed that large amount of lateral movement due to the hilly nature of the overlying strata is the main source of the problem. A simple two-dimensional study on a simulated model also demonstrated the occurrence of the problem during working below an unconfined rock mass of hilly nature. Different evidences were collected from the site to identify the main horizons and the direction of lateral movement and, accordingly, two different strata management plans, one for each section, were successfully executed to overcome the encountered strata control problems. Field investigations in the rest of the panels of the site showed favourable impact of the adopted strata management plan.     

福州“夹心层”群体期待住房保障初探

本文针对当前福州“夹心层”群体实施“经济租用房”制度现状与问题的分析,探析其出路与对策。     

煤矿井工开采过程产生的生态影响及生态恢复研究

针对煤炭开采引发的一系列生态问题,对煤矿井工开采产生的生态影响进行了分析,并相应提出预防控制措施、工程技术及减缓措施,使煤矿在开采过程中对生态环境的破坏降至最低。     

坚硬顶板水压致裂控制理论与成套技术

煤矿坚硬顶板具有硬度大、整体性好、分层厚度大等特点,导致诸多围岩控制与安全难题。水压致裂可改造顶板岩体结构,控制工作面顶板的冒落;提出坚硬顶板水压致裂控制的理论与成套技术框架。采用真三轴实验系统等研究揭示水压裂缝的扁椭球体典型形态和空间转向扩展形态,给出围压主应力差、排量、层面与原生裂隙等对水压裂缝扩展的影响规律,考虑围岩的应力应变状态与控顶效果,阐明定向压裂临空坚硬悬顶的断顶线位置适当内错煤柱的原理。给出采动岩体水压致裂的时空关系及确定方法。针对裂缝形态的控制要求,提出定向水力割缝致裂等系统的控制致裂方法,在此基础上研制煤矿井下高压(60 MPa)水压致裂的成套装备。针对不同类型工程特点,控制水压主裂缝扩展、翼型裂纹扩展和吸水湿润作用,使顶板及时充分冒落,实现围岩弱化、应力转移、诱导矿压破煤等功能。研发了工作面端头悬顶、切眼及中部坚硬顶板、坚硬顶煤弱化、综放面初采瓦斯、临空巷道冲击地压和大变形等控制成套工艺技术。成套技术与装备已在大同矿区、神东矿区等推广应用。与传统爆破弱化顶板相比,水压致裂弱化顶板管理简单、扰动小、安全性高、工程量少、作用范围大、控制距离远,且经济成本不到其1/10,在深部开采中更具有优势。     

Evaluation of subsidence due to underground coal mining: an example from the Czech Republic

This paper presents a case study dealing with variations on the ground surface due to the underground mining activities in the Ostrava–Karvina Coal District (Czech Republic) over the last 25 years. During this period, some of the areas have experienced settlements of up to 11 m. Seven settlement intervals were used to indicate the varying degrees of subsidence over time. Maps were prepared to show the spatial relationship of the subsidence and to assist in land use planning in this rapidly developing area.     

金属矿充填开采岩体移动对竖井围岩的变形破坏

采用数值模拟和地质力学分析的方法,对甘肃金川二矿区地下开采条件下, ^# 14 行风井变形破坏问题进行了研究,研究结果表明： ^# 14 行风井位于地下开采引起的岩体移动盆地的拉张区,受岩体移动变形影响剧烈,地下开采已经成为了影响竖井安全稳定的主要因素;无论是富矿开采还是贫矿富矿联合开采,竖井井壁的位移和应力分布规律大体相同,其大小与分布特征受断层影响突出,断层所在的部位仍然是竖井井壁的脆弱部位;地下开采引起的 ^# 14 行风井的破坏是以穿过井筒的断层出现活化为触发因素,以井壁发生错动、破裂、冒落为主要形式的断层效应的集中体现,这也将成为现阶段生产条件下竖井可能再次发生变形、破坏的模式。     

Monitoring and modelling progressive rehabilitation in aggregate mining ... A decade of ontario experience and a look at the future

One of the main obstacles to easy minerals accessibility is nothing to do with the geological resource, rather, it is the past record of social and environmental damage and conflicts caused by poor mining practices. In Ontario much of this focuses on the issues of progressive rehabilitation—returning land speedily and effectively to some alternative, societally acceptable and productive land use. The public continues to be upset at the unwarranted removal of good farmland from agriculture— the lengthy period of its remaining in an unproductive and unsightly condition and the uncertainty of its being returned to a fertile condition. Starting in 1971 the Ontario government became involved in regulatory control of the aggregate industry. After millions of dollars of research and a decade of experience, this paper documents the results. The paper isolates the main failings of the government programme and provides several models which if implemented will speedily remove the flaws and resolve much of the present public credibility problem with present mining practice and government control.