The influence mechanism of light rare earth elements, which are transited to the welding seam of low-alloy high strength (LAHS) steel through the covering of t he electrode, on the toughness of the welding seam was s...The influence mechanism of light rare earth elements, which are transited to the welding seam of low-alloy high strength (LAHS) steel through the covering of t he electrode, on the toughness of the welding seam was studied. The experimental results show that proper amount of rare earth elements can desulfurate, dehydro genate, reduce inclusions and purify the structure of the welding seam. Rare ear th element additions have the effect on welding seam and, at the same time, the transformation of side-batten ferrite is resisted while the pin-ferrite s tructure is promoted. The improvement of the toughness of the welding seam is du e to the purifying action of rare earth elements as well as their refining effec t on the structure. However, the toughness of the welding seam can decrease whe n the amount of light rare earth elements are added excessively because the crys tal grains become coarser, porosities appear and the inclusions increase as well . The experimental results show that the suitable amount of light rare earth ele ment additions is about 2%.展开更多
Being different from avoidance of singularity of closed-loop linkages, this paper employs the kinematic singularity to construct compliant mechanisms with expected nonlinear stiffness characteristics to enrich the met...Being different from avoidance of singularity of closed-loop linkages, this paper employs the kinematic singularity to construct compliant mechanisms with expected nonlinear stiffness characteristics to enrich the methods of compliant mechanisms synthesis. The theory for generating kinetostatic nonlinear stiffness characteristic by the kinematic limb-singularity of a crank-slider linkage is developed. Based on the principle of virtual work, the kinetostatic model of the crank-linkage with springs is established. The influences of spring stiffness on the toque-position angle relation are analyzed. It indicates that corresponding spring stiffness may generate one of four types of nonlinear stiffness characteristics including the bi-stable, local negative-stiffness, zero-stiffness or positive-stiffness when the mechanism works around the kinematic limb-singularity position. Thus the compliant mechanism with an expected stiffness characteristic can be constructed by employing the pseudo rigid-body model of the mechanism whose joints or links are replaced by corresponding flexures. Finally, a tri-symmetrical constant-torque compliant mechanism is fabricated, where the curve of torque-position angle is obtained by an experimental testing. The measurement indicates that the compliant mechanism can generate a nearly constant-torque zone.展开更多
The terminology of "fuzzy logic" has been formed and employed with different meanings bya large number of researchers soon after Zadeh published his initiate paper (see [1]), butperhaps the most serious work...The terminology of "fuzzy logic" has been formed and employed with different meanings bya large number of researchers soon after Zadeh published his initiate paper (see [1]), butperhaps the most serious work on fuzzy logic is the Pavelka’s series papers (see [2]) whichprovided a systematical theory of fuzzy logic mathematically and profoundly, and hence展开更多
In this article, we first introduce the general linear elliptic complex equation of first order with certain conditions, and then propose discontinuous Riemann-Hilbert problem and some kinds of modified well-posed-nes...In this article, we first introduce the general linear elliptic complex equation of first order with certain conditions, and then propose discontinuous Riemann-Hilbert problem and some kinds of modified well-posed-ness for the complex equation. Then we verify the equivalence of three kinds of well-posed-ness. The discontinuous boundary value problem possesses many applications in mechanics and physics etc.展开更多
<div style="text-align:justify;"> In the fast-moving world, it is noticed that every industry is developing gradually, but recently it is identified that the use of AI has become the talk of own. There...<div style="text-align:justify;"> In the fast-moving world, it is noticed that every industry is developing gradually, but recently it is identified that the use of AI has become the talk of own. Therefore, this study is focused on gathering data regarding the AI on how it has transformed the entire world’s corporate sector. The essential application AI in the business world helps the business to perform better in the corporate sector. In this paper, the critical role of artificial intelligence is to grow business in different sectors and also address its ethical and unethical issues. The paper has all the initial background and comprehensive literature regarding AI and machine learning. It is discovered how the technological world has been striving to take their business on to new heights, which requires updated technological changes in internal business activities. Companies can now effortlessly interact with their customers in making their application accessible for the end-users through implementing AI and machine learning. Companies are getting higher profitability and enhancing their performance and achieving economic advantages by integrated AI. Moreover, their technological developments will take human jobs in the future, so, it is suggested that humans should work on their skills and competencies so that they can deal with unemployment. </div>展开更多
Current research study consists of determining the optimum location of the shear wall to get the maximum structural efficiency of a reinforced concrete frame building. It consists of a detailed analysis and design rev...Current research study consists of determining the optimum location of the shear wall to get the maximum structural efficiency of a reinforced concrete frame building. It consists of a detailed analysis and design review of a seven-story reinforced concrete building to understand the effect of shear wall location on the response of reinforced concrete structures when subjected to different earthquake forces. Three trail locations of shear walls are selected and their performance is monitored in terms of structural response under different lateral loads. Required objectives are achieved by obtaining design and construction drawings of an existing reinforced concrete structure and modeling it on Finite Element Method (FEM) based computer software. The structure is redesigned and discussed with four different configurations (one without shear wall and three with shear walls). Main framing components (Beams, Columns and Shear walls) of the superstructure are designed using SAP 2000 V. 19.0 whereas substructure (foundation) of RC building was?designed using SAFE. American Concrete Institute (ACI) design specifications were used to calculate the cracked section stiffness or non-linear geometrical properties of the cracked section. Uniform Building Code (UBC-97) procedures were adopted to calculate the lateral earthquake loading on the structures. Structural response of the building was monitored at each story level for each earthquake force zone described by the UBC-97. The earthquake lateral forces were considered in both X and Y direction of the building. Each configuration of shear wall is carefully analyzed and effect of its location is calibrated by the displacement response of the structure. Eccentricity to the lateral stiffness of the building is imparted by changing the location of shear walls. Results of the study have shown that the location of shear wall significantly affects the lateral response of the structure under earthquake forces. It also motivates to carefully decide the center of lateral stiffness of building prior to deciding the location of shear walls.展开更多
With the challenge of great growing of services diversity,service-oriented supporting ability is required by current high-speed passive optical network( PON). Aimed at enhancing the quality of service( Qo S) brought b...With the challenge of great growing of services diversity,service-oriented supporting ability is required by current high-speed passive optical network( PON). Aimed at enhancing the quality of service( Qo S) brought by diversified-services,this study proposes an echo state network( ESN)based multi-service awareness mechanism in 10-Gigabite ethernet passive optical network( 10GEPON). In the proposed approach,distributed architecture is adopted to realize this ESN based multi-service awareness. According to the network architecture of 10G-EPON,where a main ESN is running in OLT and a number of ESN agents works in ONUs. The main-ESN plays the main function of service-awareness from the total view of various kinds of services in 10G-EPON system,by full ESN training. Then,the reservoir information of well-trained ESN in OLT will be broadcasted to all ONUs and those ESN agents working in ONUs are allowed to conduct independent service-awareness function. Thus,resources allocation and transport policy are both determined only in ONUs. Simulation results show that the proposed mechanism is able to better support the ability of multiple services.展开更多
文摘The influence mechanism of light rare earth elements, which are transited to the welding seam of low-alloy high strength (LAHS) steel through the covering of t he electrode, on the toughness of the welding seam was studied. The experimental results show that proper amount of rare earth elements can desulfurate, dehydro genate, reduce inclusions and purify the structure of the welding seam. Rare ear th element additions have the effect on welding seam and, at the same time, the transformation of side-batten ferrite is resisted while the pin-ferrite s tructure is promoted. The improvement of the toughness of the welding seam is du e to the purifying action of rare earth elements as well as their refining effec t on the structure. However, the toughness of the welding seam can decrease whe n the amount of light rare earth elements are added excessively because the crys tal grains become coarser, porosities appear and the inclusions increase as well . The experimental results show that the suitable amount of light rare earth ele ment additions is about 2%.
基金Supported by National Natural Science Foundation of China(Grant No.51605006)Research Foundation of Key Laboratory of Manufacturing Systems and Advanced Technology of Guangxi Province,China(Grant No.17-259-05-013K)
文摘Being different from avoidance of singularity of closed-loop linkages, this paper employs the kinematic singularity to construct compliant mechanisms with expected nonlinear stiffness characteristics to enrich the methods of compliant mechanisms synthesis. The theory for generating kinetostatic nonlinear stiffness characteristic by the kinematic limb-singularity of a crank-slider linkage is developed. Based on the principle of virtual work, the kinetostatic model of the crank-linkage with springs is established. The influences of spring stiffness on the toque-position angle relation are analyzed. It indicates that corresponding spring stiffness may generate one of four types of nonlinear stiffness characteristics including the bi-stable, local negative-stiffness, zero-stiffness or positive-stiffness when the mechanism works around the kinematic limb-singularity position. Thus the compliant mechanism with an expected stiffness characteristic can be constructed by employing the pseudo rigid-body model of the mechanism whose joints or links are replaced by corresponding flexures. Finally, a tri-symmetrical constant-torque compliant mechanism is fabricated, where the curve of torque-position angle is obtained by an experimental testing. The measurement indicates that the compliant mechanism can generate a nearly constant-torque zone.
文摘The terminology of "fuzzy logic" has been formed and employed with different meanings bya large number of researchers soon after Zadeh published his initiate paper (see [1]), butperhaps the most serious work on fuzzy logic is the Pavelka’s series papers (see [2]) whichprovided a systematical theory of fuzzy logic mathematically and profoundly, and hence
文摘In this article, we first introduce the general linear elliptic complex equation of first order with certain conditions, and then propose discontinuous Riemann-Hilbert problem and some kinds of modified well-posed-ness for the complex equation. Then we verify the equivalence of three kinds of well-posed-ness. The discontinuous boundary value problem possesses many applications in mechanics and physics etc.
文摘<div style="text-align:justify;"> In the fast-moving world, it is noticed that every industry is developing gradually, but recently it is identified that the use of AI has become the talk of own. Therefore, this study is focused on gathering data regarding the AI on how it has transformed the entire world’s corporate sector. The essential application AI in the business world helps the business to perform better in the corporate sector. In this paper, the critical role of artificial intelligence is to grow business in different sectors and also address its ethical and unethical issues. The paper has all the initial background and comprehensive literature regarding AI and machine learning. It is discovered how the technological world has been striving to take their business on to new heights, which requires updated technological changes in internal business activities. Companies can now effortlessly interact with their customers in making their application accessible for the end-users through implementing AI and machine learning. Companies are getting higher profitability and enhancing their performance and achieving economic advantages by integrated AI. Moreover, their technological developments will take human jobs in the future, so, it is suggested that humans should work on their skills and competencies so that they can deal with unemployment. </div>
文摘Current research study consists of determining the optimum location of the shear wall to get the maximum structural efficiency of a reinforced concrete frame building. It consists of a detailed analysis and design review of a seven-story reinforced concrete building to understand the effect of shear wall location on the response of reinforced concrete structures when subjected to different earthquake forces. Three trail locations of shear walls are selected and their performance is monitored in terms of structural response under different lateral loads. Required objectives are achieved by obtaining design and construction drawings of an existing reinforced concrete structure and modeling it on Finite Element Method (FEM) based computer software. The structure is redesigned and discussed with four different configurations (one without shear wall and three with shear walls). Main framing components (Beams, Columns and Shear walls) of the superstructure are designed using SAP 2000 V. 19.0 whereas substructure (foundation) of RC building was?designed using SAFE. American Concrete Institute (ACI) design specifications were used to calculate the cracked section stiffness or non-linear geometrical properties of the cracked section. Uniform Building Code (UBC-97) procedures were adopted to calculate the lateral earthquake loading on the structures. Structural response of the building was monitored at each story level for each earthquake force zone described by the UBC-97. The earthquake lateral forces were considered in both X and Y direction of the building. Each configuration of shear wall is carefully analyzed and effect of its location is calibrated by the displacement response of the structure. Eccentricity to the lateral stiffness of the building is imparted by changing the location of shear walls. Results of the study have shown that the location of shear wall significantly affects the lateral response of the structure under earthquake forces. It also motivates to carefully decide the center of lateral stiffness of building prior to deciding the location of shear walls.
基金Supported by the National High Technology Research and Development Programme of China(No.2012AA050804)
文摘With the challenge of great growing of services diversity,service-oriented supporting ability is required by current high-speed passive optical network( PON). Aimed at enhancing the quality of service( Qo S) brought by diversified-services,this study proposes an echo state network( ESN)based multi-service awareness mechanism in 10-Gigabite ethernet passive optical network( 10GEPON). In the proposed approach,distributed architecture is adopted to realize this ESN based multi-service awareness. According to the network architecture of 10G-EPON,where a main ESN is running in OLT and a number of ESN agents works in ONUs. The main-ESN plays the main function of service-awareness from the total view of various kinds of services in 10G-EPON system,by full ESN training. Then,the reservoir information of well-trained ESN in OLT will be broadcasted to all ONUs and those ESN agents working in ONUs are allowed to conduct independent service-awareness function. Thus,resources allocation and transport policy are both determined only in ONUs. Simulation results show that the proposed mechanism is able to better support the ability of multiple services.