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1.
ABSTRACT. This paper introduces the household interactive variable input-output (HIVIO) model to measure the effect of cost variation on industrial outputs. The model produces a variety of cost elasticities that separate out impacts on industrial prices, imports, and outputs, with “own” and “cross” elasticity components. Like the conventional input-output multipliers, these cost elasticities can be useful parameters to evaluate the substituting behavior of firms and consumers. By using the 1980 Korean input-output transactions table, we find the wage and import price effects on industrial prices, outputs, and import demands.  相似文献   
2.
The Multiregional Variable Input-Output (MRVIO) model is introduced to measure the development impact of a transportation system. The MRVIO model is a theoretically flexible, computationally simple, and cost-responsive model. Under the MRVIO model, regional input-output coefficients, trade coefficients, and trade flows become cost responsive and easy to compute. The MRVIO model is employed to measure the development impact of the Arkansas waterway during the period of 1974 to 1978. In the study, the U.S. economy is disaggregated into 3 regions and 35 industrial sectors. The MRVIO model estimates the economic conditions of these 3 regions with and without the waterway in terms of industrial output, income, employment, and trade flows.  相似文献   
3.
公共交通是我国老年人出行的主要交通方式之一,公交移动性是衡量老年人生活质量和幸福感的重要指标。从季节和空间双重维度分析老年人公交移动性的影响因素有助于深入理解老年人出行行为机制。利用公交刷卡数据和地理探测器方法分析了季节时空因子对老年人公交移动性的影响。研究发现:①不同季节中空间因子对老年人移动频率、移动半径和移动熵的解释力和显著性存在明显差异,对老年人移动性影响机制的分析应考虑时空变化的双重影响;②不同空间因子之间以及季节与空间因子之间的交互作用可以显著增强对老年人移动性空间分异的解释力,考虑多个因素的协同效应对深入理解老年人行为有一定帮助。研究试图拓宽老年人移动性影响因素的分析思路,为老年宜居城市建设和城市移动性规划提供重要支撑。  相似文献   
4.
西安城墙东门箭楼砖坯墙体风化因素研究报告   总被引:2,自引:2,他引:0  
论述了西安城墙东门箭楼的文化背景,实地考察了风化外状,并对风化外状进行了分类测试。通过对砖坯墙体材料进行化学全分析、X-射线衍射分析、吸水率测定(含他和系数)、冻融实验、泛霜实验、环境污染与水文气象监测资料的分析,研究了东门箭楼砖坯墙体不同风化外状的风化因素,同时对现代修缮用砖的理化性能及质量进行了评估。结果表明,温度的交替变化、水的冻结与融化使得砖坯裂解成碎块;干湿引起可溶盐的结晶与潮解以及自然界中的雨水、地面水或地下水、污染气体等通过溶解、水化、水解、碳酸化、氧化等方式,使得砖坯墙体表面酥碱粉化。同时说明研究适用于古建筑修缮使用的抗风化仿古青砖是当务之急。  相似文献   
5.
Relatively little is known about the possibilities and limitations of voluntary public programs. The so-called 33/50 Program for reducing releases of certain toxic chemicals into the environment provides a useful instance for examination. In an investigation of toxics-reduction outcomes, with states as units of analysis, economic and policy variables help to explain the results. In particular, channels and approaches used In communicating policy intentions are related to outcomes. Voluntary programs can make a difference, but the details of execution, including the extent and nature of field efforts, influence outcomes.  相似文献   
6.
The bodies and glazes of 27 early Western Zhou proto‐porcelain samples from Yejiashan cemetery, Hubei Province, were analysed using LA‐ICP–AES, SEM, XRD, a thermal expansion instrument and other analytical methods. The results indicated that the bodies of all samples were characterized by high silicon and low aluminium, and were made with porcelain stone raw materials found in the south of China. The glazes are typical of high‐temperature calcium glazes of the CaO (MgO) – K2O (Na2O) – Al2O3 – SiO2 series, with relatively high Mn and P content, which was probably caused by the addition of plant ashes. The physical properties and phase compositions of Yejiashan proto‐porcelain show that firing processes were still in the early stages of development in ancient China. Multivariate statistical analyses indicated that Yejiashan proto‐porcelain might have come from the Deqing area, in Zhejiang Province. These results provide new archaeological evidence for research on issues related to material flow in the Western Zhou dynasty.  相似文献   
7.
A human skull, buried about 2500 years ago in a Bronze Age cemetery at Jinggouzi, a site of an important ethnic group in ancient China, appeared to have characteristics of fibrous dysplasia. The CT images indicated a reduction in bone density and relatively homogeneous lesions. More features were revealed using CT reconstruction techniques. Lesions seen in low‐magnification images using a 3D deep‐field microscope had an irregular honeycomb‐like structure. At higher magnification, the trabeculae morphology and the gaps between the trabeculae were irregular and varied in size and shape. Paraffin‐embedded specimens stained with HE showed trabeculae with tortuous irregular arrangements varying in shape and width. The irregular trabeculae of woven bone has been described as having fibrous dysplasia. Molecular analysis of the GNAS gene indicated no mutation. This provides a non‐invasive approach for us to make more comprehensive diagnoses and to assist research into ancient human diseases.  相似文献   
8.
Yu Liu 《European Legacy》2018,23(6):674-691
Sir William Chambers was one of the most important English architects in the eighteenth-century, but both in his day and later his international recognition was closely connected with his admiration for and promotion of Chinese art, particularly Chinese landscaping. Between 1757 and 1773, Chambers published three treatises praising the ingenious mixture of nature and art in a Chinese pleasure ground, criticizing the then influential English gardener Lancelot (Capability) Brown, and trying to goad English garden design into the direction of China. He did not achieve his purposes mainly because he mixed what he knew as genuine about the Chinese gardening art with what he fantasized about it. While recent scholarship has focused on his fantasy, this article examines what Chambers knew or imagined about Chinese landscaping, what he and his detractors were for and against, and how the fiasco of his 1772 and 1773 treatises, which he brought upon himself, nevertheless helped to usher in a new phase in the English reception of Chinese landscaping ideas.  相似文献   
9.
2010年11月,陕西省子洲县裴家湾镇关王岔村出土了6件青铜容器,包括尊、瓿、盘、觚、鼎、提梁卣各1件。本文通过对铜器上遗留的工艺痕迹进行肉眼观察,对铜器的铸型设计、芯撑情况、浇注位置等铸造工艺环节以及铸后加工的细节进行了初步的判断和复原,指出该批铜器的铸造工艺与安阳出土的殷墟前期同类器物基本相同,这一结果对认识和揭示这批青铜器的学术价值具有重要的意义。  相似文献   
10.
于璐 《收藏家》2015,(2):3-10
2014年11月10日,APEC会议在北京召开,与此同时,由文化部、国家文物局与陕西、甘肃、宁夏、青海、新疆、河南六省区人民政府联合主办,中国国家博物馆承办的大型文物展览——《丝绸之路》于11月6日在北京中国国家博物馆开幕。展览汇集了来自全国16个省区市44家文博单位的490余件文物珍品,  相似文献   
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