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ABSTRACT This paper analyzes the determination of industry structure in a product market, given a monopolistic factor market. The characteristics of industry structure examined include the number of firms, their pricing and locational pattern. It is shown how a monopolistic factor owner–a landowner–structures the product market in order to extract maximum rent. Asymmetry characterizes the resulting locational pattern. All the product market firms charge different prices in equilibrium. No matter how large the number of firms competing in the product market, the landowner can always guarantee himself positive profits. The paper concludes with a discussion of possible applications and tests of the theory.  相似文献   
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The Rabat-Témara region of the Moroccan Atlantic coast reveals a succession of Quaternary palaeobeaches. This coastal area is dotted with numerous prehistoric caves. The study of the Upper Pleistocene coastal landscape associated with these caves is of paramount importance in the knowledge of human population subsistence. During the Upper Pleistocene, the ocean level changes drastically influenced the coastal geomorphology as well as the fauna assemblages. The chrono-lithostratographical analysis of the coastal sedimentary formations allows the distinction of three sequences rich in marine fauna. These sequences date from MIS 11 to MIS 5. The identification of malacofauna species from these deposits revealed 39 species, along with Bryozoans, Crustaceans, and Echinoids. These assemblages show a constant fauna cortege highlighted by the dominance of the amphi-Atlantic species Stramonita haemastoma. This species shows an increase in the number of specimens in the uppermost part of marine deposits, probably in relation with a climate warming in the MIS 5. This fauna of both intertidal rocky substrates and sandy substratum indicates environmental conditions close to the present-day Rabat-Témara coastline. As in other coastal locations of Africa from MIS 5, the Middle Stone Age Homo sapiens population benefitted from a littoral environment rich in coastal resources. Comparison between thanatocenoses and archaeological records allows us to identify both species available for Middle Stone Age population and those preferred for human use.  相似文献   
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This paper offers a re‐examination of some problems regarding the coinage of Vandal North Africa. The coinage of this barbarian successor state is one of the first non‐imperial coinages in the Mediterranean world of the fifth and sixth centuries. Based on the fine collection in the Coin Cabinet of Vienna's Kunsthistorisches Museum, this article questions the chronology of the various issues and monetary relations between the denominations under the Vandal kings, especially after the reign of Gunthamund (484–96). The Vandals needed and created a solid financial system. In terms of political, administrative and economic structures they tried to integrate their realm into the changing world of late antiquity and the early Middle Ages.  相似文献   
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The aim of this proposal is to present an original approach to the study and preservation of rock art caves. A multidisciplinary study of cave wall alteration will be performed to understand the impact of environmental context on the evolution of wall surfaces. The approach involves the choice of a cave with characteristics similar to painted caves in the studied area (Vézère Valley in Dordogne, France): e.g., cave wall alteration, lithology, morphology, etc. This selected cave is intended to become a laboratory cave, monitored for the acquisition of chemical, physical and biological environmental data on bedrock, air and fluids along with their characteristics. A cave without art or archaeological interest has been chosen specifically to conduct experiments, to make in situ analysis and to obtain samples. The results are to be completed by specific observations in several other caves and compiled in a database.  相似文献   
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The purpose of this paper is to demonstrate cross‐Channel exchange of calcareous sandstone‐type whetstones derived from the Weald (Sussex, UK) in the Roman period. The presence of this particular type of whetstone at several Roman sites on the Continent – more specifically, in Belgium, France and the Netherlands – is reported for the first time. The morphology, geological provenance, petrographic characteristics and distribution patterns are discussed, based on a comparative analysis with archaeological and geological reference material. The geological analysis identifies a common geological source for the Continental finds: the very fine‐grained, thin‐bedded, flagstone‐like calcareous sandstone beds of the Lower Cretaceous Wealden Clay Formation. These sandstones were, most probably, extracted in the north‐western part of the Weald area. The distribution pattern of the archaeological material implies the importance of personal mobility, with potential military affinities.  相似文献   
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