摘要 :
The characteristic of enterprise competitiveness is different between different life cycle stages. In this paper we surveyed the enterprise competitiveness's differences in various stages of the life cycle and the evolution model ...
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The characteristic of enterprise competitiveness is different between different life cycle stages. In this paper we surveyed the enterprise competitiveness's differences in various stages of the life cycle and the evolution model of three aspects of enterprise competitiveness as resource, capability and dynamic capability by questionnaire survey. The result shows that there are significant differences between different life cycle stages of enterprise competitiveness in China. The enterprise competitiveness is stronger and stronger during the periods from the enterprise's birth to maturity, while in the enterprise's recession period the competitiveness becomes much weaker. The competitiveness's constitutive features in each stage are as follows: in the enterprise's born stage the enterprise is lack of resources and its competition mainly relies on the ability; in the enterprise's growth stage the enterprise's resources become richer and are as important as enterprise's ability in the constitution of enterprise competitiveness; in the maturity stage the enterprise's people, money and material resources all become very rich but the role of capability in enterprise competitiveness begins to decrease; in the enterprise's recession stage the enterprise resources begin to exhaust, and the enterprise's competitiveness returns to rely on capability, and in this period the enterprise's learning ability, innovation ability and dynamic mechanisms perform worst, which will affect the enterprise's revival and lead to the ultimate death of enterprise. These conclusions have great value for reference to the enterprise's competitive strategy making for different life cycle stages.
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Polarization imaging plays an important role in various fields, especially for skylight navigation and target identification, whose imaging system is always required to be designed with high resolution, broad band, and single-lens...
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Polarization imaging plays an important role in various fields, especially for skylight navigation and target identification, whose imaging system is always required to be designed with high resolution, broad band, and single-lens structure. This paper describe such a imaging system based on light field 2.0 camera structure, which can calculate the polarization state and depth distance from reference plane for every objet point within a single shot. This structure, including a modified main lens, a multi-quadrants Polaroid, a honeycomb-liked micro lens array, and a high resolution CCD, is equal to an "eyes array", with 3 or more polarization imaging "glasses" in front of each "eye". Therefore, depth can be calculated by matching the relative offset of corresponding patch on neighboring "eyes", while polarization state by its relative intensity difference, and their resolution will be approximately equal to each other. An application on navigation under clear sky shows that this method has a high accuracy and strong robustness.
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摘要 :
Polarization imaging plays an important role in various fields, especially for skylight navigation and target identification, whose imaging system is always required to be designed with high resolution, broad band, and single-lens...
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Polarization imaging plays an important role in various fields, especially for skylight navigation and target identification, whose imaging system is always required to be designed with high resolution, broad band, and single-lens structure. This paper describe such a imaging system based on light field 2.0 camera structure, which can calculate the polarization state and depth distance from reference plane for every objet point within a single shot. This structure, including a modified main lens, a multi-quadrants Polaroid, a honeycomb-liked micro lens array, and a high resolution CCD, is equal to an "eyes array", with 3 or more polarization imaging "glasses" in front of each "eye". Therefore, depth can be calculated by matching the relative offset of corresponding patch on neighboring "eyes", while polarization state by its relative intensity difference, and their resolution will be approximately equal to each other. An application on navigation under clear sky shows that this method has a high accuracy and strong robustness.
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The objective of this work was to propose a method for dynamic testing of Poisson's ratio of dimension lumber. Based on the first-order bending mode shape of cantilever slab, Sitka Spruce was selected as research object using inst...
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The objective of this work was to propose a method for dynamic testing of Poisson's ratio of dimension lumber. Based on the first-order bending mode shape of cantilever slab, Sitka Spruce was selected as research object using instruments including four-channel dynamic resistance strain gauge and CRAS vibration and a set of collection-analysis system for dynamic signal. Free vibration of cantilever specimen of Sitka Spruce and mild steel can be stimulated by knocking, and the fundamental vibration should be reserved by filtering processing. Additionally, decaying curve of oscillatoiy waves for transverse and longitudinal strain of fundamental vibration should also be recorded and displayed. Obtained from the positive (negative) peak in oscillatoiy wave curve for transverse strain, Poisson's ratios along grain and across grain on radial section and that across grain on transverse section of Sitka Spruce specimens were measured. Then measured results were applied to analyse the accuracy of calculated modulus of elasticity obtained by plugging the first-order bending frequency measured by cantilever slab into equation of cantilever beam, and this method is proved to be robust and accurate. The method based on first-order bending mode shape of cantilever slab to measure dimension lumber Poisson's ratio is efficient and simple, with good repeatability and high accuracy. Besides, the same method was also applied to test Poisson's ratio of mild steel to validate the correctness of the method on wood. It is observed that the positive (negative) peak in oscillatory wave curve for transverse strain is corresponding to that for longitudinal strain, meaning that the phase difference, between oscillatoiy wave curves for transverse strain and longitudinal strain, is 180°, or that transverse strain and longitudinal strain are reversed. The average value should be taken after calculating the ratios between peak-to-peak values read from the first channel and the second channel in os
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In the process of 3D reconstruction of the target scene with the moving vehicle-borne single-line scanner, a method of monocular visual positioning is used to locate the exact position of the moving scanner. Attitude sensor, camer...
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In the process of 3D reconstruction of the target scene with the moving vehicle-borne single-line scanner, a method of monocular visual positioning is used to locate the exact position of the moving scanner. Attitude sensor, camera and the laser scanner are located on the same platform which is installed on the vehicle. Data can be collected synchronously. We obtained a top view according to the observation of camera's attitude by IPM. A series of planform are acquired at different moment. After dealing with these pictures with operations of extraction Speeded Up Robust Features (SURF).,matching characteristic points and RANSAC algorism, we calculated the transformation matrix between two adjacent vertical views. The position and direction of the scanner at this moment can be calculated. On this basis, depending on the sensors' synchronization control algorithm, the original point clouds data got by laser scanner can be registered as a reference to the traveling track of the moving scanner, and then the 3D reconstruction of the target scene is established. Experiment result shows that this method is easy to operate, time-efficient, low cost, and the accuracy of the method in reconstructing 3D scene is demonstrated.
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摘要 :
In the process of 3D reconstruction of the target scene with the moving vehicle-borne single-line scanner, a method of monocular visual positioning is used to locate the exact position of the moving scanner. Attitude sensor, camer...
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In the process of 3D reconstruction of the target scene with the moving vehicle-borne single-line scanner, a method of monocular visual positioning is used to locate the exact position of the moving scanner. Attitude sensor, camera and the laser scanner are located on the same platform which is installed on the vehicle. Data can be collected synchronously. We obtained a top view according to the observation of camera's attitude by IPM. A series of planform are acquired at different moment. After dealing with these pictures with operations of extraction Speeded Up Robust Features (SURF).,matching characteristic points and RANSAC algorism, we calculated the transformation matrix between two adjacent vertical views. The position and direction of the scanner at this moment can be calculated. On this basis, depending on the sensors' synchronization control algorithm, the original point clouds data got by laser scanner can be registered as a reference to the traveling track of the moving scanner, and then the 3D reconstruction of the target scene is established. Experiment result shows that this method is easy to operate, time-efficient, low cost, and the accuracy of the method in reconstructing 3D scene is demonstrated.
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With the rapid economic growth and expansion of urban area in the past over thirty years in China, the land value increased rapidly in the process of land use conversion, which has aroused great social conflicts. Model of land val...
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With the rapid economic growth and expansion of urban area in the past over thirty years in China, the land value increased rapidly in the process of land use conversion, which has aroused great social conflicts. Model of land value increment allocation is established based on the concept of land development right and applied in a case study about Guangzhou. It is concluded that according with the new approach of land value increment distribution based on LDR, special consideration for the function of social security of farmland, providing an new approach for the reform of land property right system and land compensation system reform.
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摘要 :
With the rapid economic growth and expansion of urban area in the past over thirty years in China, the land value increased rapidly in the process of land use conversion, which has aroused great social conflicts. Model of land val...
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With the rapid economic growth and expansion of urban area in the past over thirty years in China, the land value increased rapidly in the process of land use conversion, which has aroused great social conflicts. Model of land value increment allocation is established based on the concept of land development right and applied in a case study about Guangzhou. It is concluded that according with the new approach of land value increment distribution based on LDR, special consideration for the function of social security of farmland, providing an new approach for the reform of land property right system and land compensation system reform.
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Due to the existence of strengthening alloying elements in nickel-base superalloys, welding is quite difficult and the mechanical properties of the welding seam usually decrease significantly compared to the corresponding base mat...
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Due to the existence of strengthening alloying elements in nickel-base superalloys, welding is quite difficult and the mechanical properties of the welding seam usually decrease significantly compared to the corresponding base materials. In this paper, a study on laser welding of nickel-base superalloys was carried out, and the as-welded samples were treated with mechanical (Rolling) and heat treatment, and the structures and mechanical properties after treatment were investigated. It was found that before any treatment, the fusion line was obviously observed between the welding seam and base materials, and few heat affected zone was found. After rolling treatment, the tensile properties of as-welded samples were close to the base materials. Aging and solid solution treatment can improve the mechanical properties of welding seams significantly. It was indicated that aging treatment could result in the formation of plenty of TiCN precipitates in welding seams, which could be helpful for strengthening the welding seams.
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This study discusses the significance of protecting historical industrial settlements from different aspects include culture, society and economy; furthermore, it analyzes the causes of these historical settlements, generalizes th...
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This study discusses the significance of protecting historical industrial settlements from different aspects include culture, society and economy; furthermore, it analyzes the causes of these historical settlements, generalizes the essential characteristics of the settlements, and carefully analyzes the problems of the settlements under current situation. Focus on those problems, this study takes the Theory of Four Dimensional City as reference and presents principals and strategies for the renewal protection of the historical settlements. It describes the process of planning practice in detail through a specific example built under the soviet model in the initial post-liberation period.
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