Seismic exploration in the mountainous areas of western Chinese is extremely difficult because of the complexity of the surface and subsurface, which results in shooting difficulties, seismic data with low signal-to-n...Seismic exploration in the mountainous areas of western Chinese is extremely difficult because of the complexity of the surface and subsurface, which results in shooting difficulties, seismic data with low signal-to-noise ratio, and strong interference. The complexity of the subsurface structure leads to strong scattering of the refl ection points; thus, the curved-line acquisition method has been used. However, the actual subsurface structural characteristics have been rarely considered. We propose a design method for irregular acquisition based on common refl ection points（CRP） to avoid difficult-to-shoot areas, while considering the structural characteristics and CRP positions and optimizing the surfacereceiving line position. We arrange the positions of the receiving points to ensure as little dispersion of subsurface CRP as possible to improve the signal-to-noise ratio of the seismic data. We verify the applicability of the method using actual data from a site in Sichuan Basin. The proposed method apparently solves the problem of seismic data acquisition and facilitates seismic exploration in structurally complex areas.展开更多
To fabricate the comb target with low damping and high performance-price ratio,0.03-\{0.1 mm\} thickness aluminum foi l used as the conducting medium,the upper and lower surfaces covered with 0.5-1 mm thickness plasti...To fabricate the comb target with low damping and high performance-price ratio,0.03-\{0.1 mm\} thickness aluminum foi l used as the conducting medium,the upper and lower surfaces covered with 0.5-1 mm thickness plastic film,after four processes of thrusting,laminating,punching and cu tting,a 500 mm×\{500 mm\} comb target is fabricated.A 155-mm projectile expl osiv e pow er test is conducted.Using the newly fabricated comb target,the measured initi al velocity of the fragment is 2 070 m/s.Th e test results show that the new comb target is of high test pre cision,small damping,low cost and high production efficiency,and it can measure th e 2 mm×2 m m fragment's initial velocity.展开更多
When an oceanographic vessel is sailing, the currents near the surface of ship hull are rapid, making it hard to meet the environmental requirements of scientific observation equipment. To guarantee the installation s...When an oceanographic vessel is sailing, the currents near the surface of ship hull are rapid, making it hard to meet the environmental requirements of scientific observation equipment. To guarantee the installation space and environmental requirements of the observation equipment, the drop keel system was proposed for the first time for ocean-graphic ships at China, to avoid the traditional ＂rudder-shaft＂ type fin keel＇s disadvantage. The research study will examine the operational mechanism and functions of the drop keel system, the operating conditions of the fin keel to determine the driver method and its arrangement, and the locking method of the fin keel underwater. The research wilI also provide some general designs for analyzing the best plan for the drop keel system.展开更多
The circuit testable realizations of multiple-valued functions are studied in this letter. First of all,it is shown that one vector detects all skew faults in multiplication modulo circuits or in addi-tion modulo circ...The circuit testable realizations of multiple-valued functions are studied in this letter. First of all,it is shown that one vector detects all skew faults in multiplication modulo circuits or in addi-tion modulo circuits,and n+1 vectors detect all skew faults in the circuit realization of multiple-valued functions with n inputs. Secondly,min(max) bridging fault test sets with n+2 vectors are pre-sented for the circuit realizations of multiple-valued logic functions. Finally,a tree structure is used instead of cascade structure to reduce the delay in the circuit realization,it is shown that three vec-tors are sufficient to detect all single stuck-at faults in the tree structure realization of multiple-valued logic functions.展开更多
This paper analyzes conflict features in architecture pipe routing,and builds a pipe routing design conflict model by taking into account of discrete nominal internal diameter selection of pipes,material costs,and con...This paper analyzes conflict features in architecture pipe routing,and builds a pipe routing design conflict model by taking into account of discrete nominal internal diameter selection of pipes,material costs,and conflict solution sequence.Considering pipe routing as an assembling process,a conflict detection approach for pipe routing in collaborative architectural design is proposed based on an aforementioned model.Constraint network is used to describe the relationship among pipe routing design parameters and constraints;design conflicts are detected by matching designers' input and constraint network;and detected design conflicts are reordered according to the number of pipe parameters in conflicts.In order to support the collaborative requirement of pipe routing design,a prototype system using browser/server architecture is developed.An illustrative example of water pipe routing in a room is used to show the effectiveness and efficiency of the approach.展开更多
基金funded by The National Natural Science Foundation of China(No.41304115)Sichuan Province innovative team of natural gas geology Construction Program(No.13TD0024)Fund for middle-aged core teachers of SWPU
文摘Seismic exploration in the mountainous areas of western Chinese is extremely difficult because of the complexity of the surface and subsurface, which results in shooting difficulties, seismic data with low signal-to-noise ratio, and strong interference. The complexity of the subsurface structure leads to strong scattering of the refl ection points; thus, the curved-line acquisition method has been used. However, the actual subsurface structural characteristics have been rarely considered. We propose a design method for irregular acquisition based on common refl ection points（CRP） to avoid difficult-to-shoot areas, while considering the structural characteristics and CRP positions and optimizing the surfacereceiving line position. We arrange the positions of the receiving points to ensure as little dispersion of subsurface CRP as possible to improve the signal-to-noise ratio of the seismic data. We verify the applicability of the method using actual data from a site in Sichuan Basin. The proposed method apparently solves the problem of seismic data acquisition and facilitates seismic exploration in structurally complex areas.
文摘To fabricate the comb target with low damping and high performance-price ratio,0.03-\{0.1 mm\} thickness aluminum foi l used as the conducting medium,the upper and lower surfaces covered with 0.5-1 mm thickness plastic film,after four processes of thrusting,laminating,punching and cu tting,a 500 mm×\{500 mm\} comb target is fabricated.A 155-mm projectile expl osiv e pow er test is conducted.Using the newly fabricated comb target,the measured initi al velocity of the fragment is 2 070 m/s.Th e test results show that the new comb target is of high test pre cision,small damping,low cost and high production efficiency,and it can measure th e 2 mm×2 m m fragment's initial velocity.
文摘When an oceanographic vessel is sailing, the currents near the surface of ship hull are rapid, making it hard to meet the environmental requirements of scientific observation equipment. To guarantee the installation space and environmental requirements of the observation equipment, the drop keel system was proposed for the first time for ocean-graphic ships at China, to avoid the traditional ＂rudder-shaft＂ type fin keel＇s disadvantage. The research study will examine the operational mechanism and functions of the drop keel system, the operating conditions of the fin keel to determine the driver method and its arrangement, and the locking method of the fin keel underwater. The research wilI also provide some general designs for analyzing the best plan for the drop keel system.
基金Supported by the National Natural Science Foundation of China (No.60006002)the Education Department of Guangdong Province of China (No.02019).
文摘The circuit testable realizations of multiple-valued functions are studied in this letter. First of all,it is shown that one vector detects all skew faults in multiplication modulo circuits or in addi-tion modulo circuits,and n+1 vectors detect all skew faults in the circuit realization of multiple-valued functions with n inputs. Secondly,min(max) bridging fault test sets with n+2 vectors are pre-sented for the circuit realizations of multiple-valued logic functions. Finally,a tree structure is used instead of cascade structure to reduce the delay in the circuit realization,it is shown that three vec-tors are sufficient to detect all single stuck-at faults in the tree structure realization of multiple-valued logic functions.
基金Supported by the National High Technology Research and Development Programme of China(No.2006AA04Z112)the National Natural Science Foundation of China(No.51175287)the National S&T Major Program(No.2009ZX02001-003)
文摘This paper analyzes conflict features in architecture pipe routing,and builds a pipe routing design conflict model by taking into account of discrete nominal internal diameter selection of pipes,material costs,and conflict solution sequence.Considering pipe routing as an assembling process,a conflict detection approach for pipe routing in collaborative architectural design is proposed based on an aforementioned model.Constraint network is used to describe the relationship among pipe routing design parameters and constraints;design conflicts are detected by matching designers' input and constraint network;and detected design conflicts are reordered according to the number of pipe parameters in conflicts.In order to support the collaborative requirement of pipe routing design,a prototype system using browser/server architecture is developed.An illustrative example of water pipe routing in a room is used to show the effectiveness and efficiency of the approach.
