Boulder block ramps are river engineering structures used to stabilise river beds. Block ramps provide a semi-natural and aesthetically pleasing solution to certain river engineering problems in mountain streams. When...Boulder block ramps are river engineering structures used to stabilise river beds. Block ramps provide a semi-natural and aesthetically pleasing solution to certain river engineering problems in mountain streams. When constructing block ramps,one can use the dissipative behaviour of large macroroughness elements randomly placed on the river bed to enhance fish migration in an upstream direction thus, in this sense, meeting the requirements of the EU Water Framework Directive. Block ramps are often designed and constructed to replace damaged drop hydraulic structures in the channels of mountain streams. This paper investigates the resilience of a particular block ramp placed in the Krzczonówka stream(Polish Carpathians) in terms of the engineering design function and its durability against damaging. A hydrodynamic analysis of a block ramp is presented before and after a flood event that changed the configuration of the blocks. The seminatural unstructured hydraulic structure was built on the Krzczonowka stream to protect gas pipes which are located beneath it. As a result of several floods, the boulder block chute described in this paper was damaged, and some boulders were dislodged and transported downstream. Our post-flood investigations of bathymetry and velocity revealed that even damaged boulder blocks, removed from the chute and displaced downstream of the structure, still provide significant energy dissipation of the flowing water. The novel of our paper is for the first time showing very detailed analysis of unstructured block ramp hydrodynamics parameters done in the field.Also the novel finding of our investigations shows that before and after the flood event the unstructured block ramp structure, is still fish friendly in terms of hydrodynamics.展开更多
In contrast to the previous studies of knowledge capital from the perspective of enterprises, this study discusses the employee knowledge capital formation mechanism in the supply chain using social network method fro...In contrast to the previous studies of knowledge capital from the perspective of enterprises, this study discusses the employee knowledge capital formation mechanism in the supply chain using social network method from the perspective of social capital s~＇ucture, taking individual employees as the study objects. 150 effective questionnaires of three groups were returned by multistage cluster sampling, and then they were analyzed through regression and the structural equation model. The results are as follows： （1） the acquisition of social capital and knowledge capital is affected by the network structure position of the employees in the supply chain; （2） the knowledge capital is affected by how much social capital the employees obtained in the supply chain; （3） social capital is an intermediary variable to affect the knowledge capital in the network structure. Finally, related suggestions for the supply chain management and the subsequent studies are proposed. 1展开更多
基金financed by the Ministry of Science and Higher Education of the Republic of Poland: 1. Cracow University of Technology, Faculty of Civil Engineering: L4/106/2018/DS, L4/107/2018/DS and L4/585/2018/DS-M. 2. University of Agriculture in Krakow: BM2313/KIWi G/2018
文摘Boulder block ramps are river engineering structures used to stabilise river beds. Block ramps provide a semi-natural and aesthetically pleasing solution to certain river engineering problems in mountain streams. When constructing block ramps,one can use the dissipative behaviour of large macroroughness elements randomly placed on the river bed to enhance fish migration in an upstream direction thus, in this sense, meeting the requirements of the EU Water Framework Directive. Block ramps are often designed and constructed to replace damaged drop hydraulic structures in the channels of mountain streams. This paper investigates the resilience of a particular block ramp placed in the Krzczonówka stream(Polish Carpathians) in terms of the engineering design function and its durability against damaging. A hydrodynamic analysis of a block ramp is presented before and after a flood event that changed the configuration of the blocks. The seminatural unstructured hydraulic structure was built on the Krzczonowka stream to protect gas pipes which are located beneath it. As a result of several floods, the boulder block chute described in this paper was damaged, and some boulders were dislodged and transported downstream. Our post-flood investigations of bathymetry and velocity revealed that even damaged boulder blocks, removed from the chute and displaced downstream of the structure, still provide significant energy dissipation of the flowing water. The novel of our paper is for the first time showing very detailed analysis of unstructured block ramp hydrodynamics parameters done in the field.Also the novel finding of our investigations shows that before and after the flood event the unstructured block ramp structure, is still fish friendly in terms of hydrodynamics.
文摘In contrast to the previous studies of knowledge capital from the perspective of enterprises, this study discusses the employee knowledge capital formation mechanism in the supply chain using social network method from the perspective of social capital s~＇ucture, taking individual employees as the study objects. 150 effective questionnaires of three groups were returned by multistage cluster sampling, and then they were analyzed through regression and the structural equation model. The results are as follows： （1） the acquisition of social capital and knowledge capital is affected by the network structure position of the employees in the supply chain; （2） the knowledge capital is affected by how much social capital the employees obtained in the supply chain; （3） social capital is an intermediary variable to affect the knowledge capital in the network structure. Finally, related suggestions for the supply chain management and the subsequent studies are proposed. 1
