Objective To investigate the effects of the topical use of aprotinin on thebasis of comprehensive blood conservations in cardiopulmonary bypass (CPB). Methods In a prospectiveclinical trial, 20 patients were randomly ...Objective To investigate the effects of the topical use of aprotinin on thebasis of comprehensive blood conservations in cardiopulmonary bypass (CPB). Methods In a prospectiveclinical trial, 20 patients were randomly divided into 2 groups. Control group: placebo was usedtopically. Aprotinin group: aprotinin was poured into the pericardial cavity before closure of thesternotomy. Before and 24h after surgery, hemoglobin (Hb), hematocrit (Hct), bleeding time (BT),clotting time (CT) and prothrombin time (PT) were measured. Meanwhile, amounts of the mediastinaldrainage and the hemoglobin loss were observed at 0, 2, 6 and 24h after operation. The samples fromthe mediastinal drainage were also collected to measure D-Dimer (D-D), tissue type plasminogenactivator (t-PA) activity, plasminogen activator inhibitor (PAI) activity and protein C (PC).Results In Aprotinin group, D-D, t-PA activity and PC were significantly reduced, compared withthose in Control group (P<0.05, P<0.05, P<0.01). On the contrary, PAI activity was significantlyincreased, compared with that in Control group. Amounts of the mediastinal drainage and thehemoglobin loss were decreased by 43% and 52%, compared with those in Control group. Conclusion Ourresults suggest that the topical use of aprotinin can have better effects on the basis ofcomprehensive moderate blood conservation.展开更多
Objective To explore the efficacy of target positioning by preoperative CT/MRI image fusion technique in deep brain stimulation.Methods We retrospectively analyzed the clinical data and images of 79 cases(68 with Park...Objective To explore the efficacy of target positioning by preoperative CT/MRI image fusion technique in deep brain stimulation.Methods We retrospectively analyzed the clinical data and images of 79 cases(68 with Parkinson's disease,11 with dystonia) who received preoperative CT/MRI image fusion in target positioning of subthalamic nucleus in deep brain stimulation.Deviation of implanted electrodes from the target nucleus of each patient were measured.Neurological evaluations of each patient before and after the treatment were performed and compared.Complications of the positioning and treatment were recorded.Results The mean deviations of the electrodes implanted on X,Y,and Z axis were 0.5 mm,0.6 mm,and 0.6 mm,respectively.Postoperative neurologic evaluations scores of unified Parkinson's disease rating scale(UPDRS) for Parkinson's disease and Burke-Fahn-Marsden Dystonia Rating Scale(BFMDRS) for dystonia patients improved significantly compared to the preoperative scores(P<0.001); Complications occurred in 10.1%(8/79) patients,and main side effects were dysarthria and diplopia.Conclusion Target positioning by preoperative CT/MRI image fusion technique in deep brain stimulation has high accuracy and good clinical outcomes.展开更多
With the objective of establishing the necessary conditions for 3D seismic data from mountainous areas in western China, we compared the application results of wave impedance technology in the lithology and exploratio...With the objective of establishing the necessary conditions for 3D seismic data from mountainous areas in western China, we compared the application results of wave impedance technology in the lithology and exploration of coal fields. First, we introduce principles and features of three kinds of inversion methods. i.e., Model-Based Inversion, Constrained Sparse Spike Inversion (CSSI) and Geology-Seismic Feature Inversion. Secondly, these inversion methods are contrasted in their application to 3D seismic data from some coalfields in western China. The main information provided by the research includes: improving the vertical resolution of coal deposit strata, inferring lateral variation of the lithology and predicting coal seams and their roof lithology. Finally, the comparison between the three methods shows that the model-based inversion has the higher resolution, while CSSI inversion has better waveform continuity. The geology-seismic feature inversion requires information from a large number of wells and many types of logging curves of good quality. All three methods can meet the requirements of seismic exploration for lithological exploration in coal fields.展开更多
The coal mine roof rating(CMRR) is a measure of roof quality or structure competency for bedded roof types typically of underground coal mines. The CMRR has been used widely in the US, South Africa,Canada and Australi...The coal mine roof rating(CMRR) is a measure of roof quality or structure competency for bedded roof types typically of underground coal mines. The CMRR has been used widely in the US, South Africa,Canada and Australia. In order to investigate the application of the CMRR system in Chinese coal mines,two coal mines in China located in Panjiang Coal Field in Guizhou Province were investigated. Field data were collected which is required to calculate the CMRR value based on underground exposure. The CMRR values of 11 locations in two coal mines were calculated. The investigations demonstrated that the chance of mine roof failure is very low if the CMRR value is more than 50, given adequate support is installed in mine. It was found that the CMRR guideline are useful to preliminarily investigate stability in Panjiang Coal Field mines.展开更多
An element coupling model (ECM) method was proposed to simulate the global behavior and local damage of a structure.In order to reflect the local damage and improve the computational efficiency,three-dimensional (3D) ...An element coupling model (ECM) method was proposed to simulate the global behavior and local damage of a structure.In order to reflect the local damage and improve the computational efficiency,three-dimensional (3D) solid elements and one-dimensional (1D) beam element were coupled by the multi-point constraint equations.A reduced scale 1?8 model test was simulated by the ECM and a full three dimensional model (3DM) contrastively.The results show that the global behavior and local damages of ECM agree well with the test and 3DM.It is indicated that the proposed method can be used in the structural nonlinear analysis accurately and efficiently.展开更多
The configuration principles and functions of the non-contact three-dimensional (3D) body measurement system (BMS) developed by the Textile/Clothing Technology Corporation ([TC]^2) are described in this paper. T...The configuration principles and functions of the non-contact three-dimensional (3D) body measurement system (BMS) developed by the Textile/Clothing Technology Corporation ([TC]^2) are described in this paper. The advantages of this new system, compared with traditional contact body measurement instruments ( Martin instruments ) are discussed by selecting 40 female undergraduates of Donghna University as the scan objects. In the experiments both the Martin instruments and [TC]^2 BMS were used respectively. According to the data of different position (Bust Circumference, Full Waist, Full Hips, Bust Height, Front Waist Height and Back Waist Height) obtained from both of the methods we can get the correlation coefficient which is close to 1, indicating that the results of both methods have comparability. Finally some suggestions for the further applications of the non-contact BMS in the apparel development of China are given.展开更多
After the nuclear power plant accident in Japan, Korean government has set the national goal to produce the electricity by renewable energy sources up to 11% by 2035 which is not easy to achieve without ocean energy d...After the nuclear power plant accident in Japan, Korean government has set the national goal to produce the electricity by renewable energy sources up to 11% by 2035 which is not easy to achieve without ocean energy development. The demand on the clean energy supply has been increased recently and there are many renewable energy development projects and plans announced worldwide. The ocean energy can be produced from tidal current, wave, tidal barrage and ocean thermal sources. The first step is to estimate the resource assessment for each energy source. There are several assessment methods introduced from IEA (International Energy Agency), IRENA (International Renewable Energy Agency), NREL (National Renewable Energy Laboratory), EU ERENE (European Community for Renewable Energy), Bonn University, DLR (German Aerospace Center), etc.. Even these known methods have some sort of similarity; there are different definitions and classifications among them. In this paper, the four-step energy potentials are defined and introduced as theoretical, geographical, technical and market potentials. The theories for each step are presented for ocean energies together with clear definitions. As the tidal current energy research and development are active in Korea having very strong tidal current speed along the west and south coastal regions, the detail procedure for each step of energy potential assessment is introduced for tidal current energy. The paper will illustrate the case study of tidal current power assessment in western coastal region, South Korea with highlighting the key aspects in determining the resource potentials.展开更多
This study emphasizes the advantage of tectonic phase separation in determination of a tectonic evolution of complicated fault zones. The research focused on the Sudetic Marginal Fault Zone(SMFZ) –a 250 km long activ...This study emphasizes the advantage of tectonic phase separation in determination of a tectonic evolution of complicated fault zones. The research focused on the Sudetic Marginal Fault Zone(SMFZ) –a 250 km long active fault zone with documented intraplate seismicity situated on the NE margin of the Bohemian Massif(the Czech Republic). The tectonic history of the SMFZ as well as its kinematic development has been rather complicated and not quite understood. A field structural investigation was carried out in extensive surroundings of the fault zone. The fault-slip data were collected in a number of natural outcrops and quarries with the aim at establishing a robust and field-constrained model for local brittle structural evolution of the studied area. A paleostress analysis was calculated using the collected fault-slip data inversion. The T-Tecto software was utilized for semiautomatic separation of the paleostress phases. Simultaneously three methods of data separation were employed:(1) the Gauss inverse method,(2) the Visualization of Gauss object Function, and(3) the frequency analysis. Within the fault zone multiphase movements were observed on various types of faults as well as wide range of the kinematic indicators orientations. The frequency analysis confirmed the multiphase history of the SMFZ. The calculated tectonic phases were divided according to their relative age as constrained by cross cutting relationships and, where observed, multiple striations on a single fault plane and classified from the oldest to the younger. Data separation and inversion usingT-Tecto software with the Gauss inverse method revealed four different stress phases which are 3 strike-slip stress regimes and one compressional regime. The strike-slip regimes are characterized by σ1 trending NW-SE(43), NNE-SSW(18), ENE-WSW(76) and the compressional one by σ1 trending W-E(26). First, compression occurred parallel to the SMFZ supposedly during the Variscan period. Second, compression at an angle of 60° to general direction of the SMFZ yielded right-lateral movement along the fault zone. This is considered to have occurred during the late-Variscan and post-Variscan period. Third, compression in the W-E direction with almost vertical extension led to reverse movement along the fault zone. This is considered to have occurred during Cenozoic. Fourth, compression almost perpendicular to the SMFZ led to left-lateral transpression along the SMFZ. This is considered to have occurred during Quaternary.展开更多
As an alternative power source for hybrid electrical vehicle(HEV), electric generating system(EGS) driven by sphere cam engine(SCE) is said to own higher power density and integration. In this work, the structure and ...As an alternative power source for hybrid electrical vehicle(HEV), electric generating system(EGS) driven by sphere cam engine(SCE) is said to own higher power density and integration. In this work, the structure and working principle of EGS were introduced, based on which the advantages of EGS were displayed. The profile of sphere cam was achieved after the desired motion of piston was given. After establishing the dynamic model of power transmission mechanism, the characteristics of cam-roller mechanism were studied. The results show that the optimal cam profile of SCE is a sinusoid curve which has two peaks and two valleys and a mean pressure angle of 47.19°. Because of the special cam shape, the trace of end surface center of piston is an eight-shape curve on a specific sphere surface. SCE running at speed of 3000 r/min can generate the power of 33.81 kW, which could satisfy the need of HEVs. However, the force between cylinder and piston skirt caused by Coriolis acceleration can reach up to 1182 N, which leads to serious wear between cylinder liner and piston skirt and may shorten the lifespan of SCE.展开更多
Serious shaft lining failures often occur when shaft linings are constructed by passing them through the deep topsoil of Quaternary strata. This approach also leads to the formation of an aquifer at the bottom.Based o...Serious shaft lining failures often occur when shaft linings are constructed by passing them through the deep topsoil of Quaternary strata. This approach also leads to the formation of an aquifer at the bottom.Based on the theory of the additional stress which is the main reason for these failures, this study focuses on the treatment effect of underground continuous impervious curtain(UCIC) in terms of different factors, namely, the location, shape, range, and width, by using numerical simulation. Results show that the UCIC can reduce the stress concentration in the shaft lining formed in the bottom aquifer. The UCIC can also reinforce the shaft lining at different angles and can be applied in actual situations. The strength factors of the inner surface of the shaft lining increase after the UCIC are used. The material strength and width of the UCIC show an obvious effect on the stability of the shaft lining. Results proved that the UCIC could effectively strengthen the stability of the shaft lining when it was built in the aquifer or built in the aquifer and above and below the layer.展开更多
In soft sensor field, just-in-time learning(JITL) is an effective approach to model nonlinear and time varying processes. However, most similarity criterions in JITL are computed in the input space only while ignoring...In soft sensor field, just-in-time learning(JITL) is an effective approach to model nonlinear and time varying processes. However, most similarity criterions in JITL are computed in the input space only while ignoring important output information, which may lead to inaccurate construction of relevant sample set. To solve this problem, we propose a novel supervised feature extraction method suitable for the regression problem called supervised local and non-local structure preserving projections(SLNSPP), in which both input and output information can be easily and effectively incorporated through a newly defined similarity index. The SLNSPP can not only retain the virtue of locality preserving projections but also prevent faraway points from nearing after projection,which endues SLNSPP with powerful discriminating ability. Such two good properties of SLNSPP are desirable for JITL as they are expected to enhance the accuracy of similar sample selection. Consequently, we present a SLNSPP-JITL framework for developing adaptive soft sensor, including a sparse learning strategy to limit the scale and update the frequency of database. Finally, two case studies are conducted with benchmark datasets to evaluate the performance of the proposed schemes. The results demonstrate the effectiveness of LNSPP and SLNSPP.展开更多
The cylindrical shell is one of the main structural parts in ocean engineering structures.These cylinders are mostly of medium length,which means that the radius of the cross section is significantly smaller than the ...The cylindrical shell is one of the main structural parts in ocean engineering structures.These cylinders are mostly of medium length,which means that the radius of the cross section is significantly smaller than the length of the cylindrical shell.From the viewpoint of the shell theory,they belong to the mid-long cylindrical shell category.To solve mechanical problems on this kind of structure,especially a cracked cylindrical shell,analysis based on shell theory is necessary.At present the generally used solving system for the mid-long cylindrical shell is too complicated,difficult to solve,and inapplicable to engineering.This paper introduced the Sanders' mid-long cylindrical shell theory which reduces the difficulty of the solution process,and will be suitable for solving problems with complicated boundary conditions.On this basis,the engineering applications of this theory were discussed in conjunction with the problem of a mid-long cylindrical shell having a circumferential crack.The solution process is simple,and the closed form solution can usually be found.In practical engineering applications,it gives satisfactory precision.展开更多
基金Supported by the Jiangsu Health Bureau Grand (B9606)
文摘Objective To investigate the effects of the topical use of aprotinin on thebasis of comprehensive blood conservations in cardiopulmonary bypass (CPB). Methods In a prospectiveclinical trial, 20 patients were randomly divided into 2 groups. Control group: placebo was usedtopically. Aprotinin group: aprotinin was poured into the pericardial cavity before closure of thesternotomy. Before and 24h after surgery, hemoglobin (Hb), hematocrit (Hct), bleeding time (BT),clotting time (CT) and prothrombin time (PT) were measured. Meanwhile, amounts of the mediastinaldrainage and the hemoglobin loss were observed at 0, 2, 6 and 24h after operation. The samples fromthe mediastinal drainage were also collected to measure D-Dimer (D-D), tissue type plasminogenactivator (t-PA) activity, plasminogen activator inhibitor (PAI) activity and protein C (PC).Results In Aprotinin group, D-D, t-PA activity and PC were significantly reduced, compared withthose in Control group (P<0.05, P<0.05, P<0.01). On the contrary, PAI activity was significantlyincreased, compared with that in Control group. Amounts of the mediastinal drainage and thehemoglobin loss were decreased by 43% and 52%, compared with those in Control group. Conclusion Ourresults suggest that the topical use of aprotinin can have better effects on the basis ofcomprehensive moderate blood conservation.
文摘Objective To explore the efficacy of target positioning by preoperative CT/MRI image fusion technique in deep brain stimulation.Methods We retrospectively analyzed the clinical data and images of 79 cases(68 with Parkinson's disease,11 with dystonia) who received preoperative CT/MRI image fusion in target positioning of subthalamic nucleus in deep brain stimulation.Deviation of implanted electrodes from the target nucleus of each patient were measured.Neurological evaluations of each patient before and after the treatment were performed and compared.Complications of the positioning and treatment were recorded.Results The mean deviations of the electrodes implanted on X,Y,and Z axis were 0.5 mm,0.6 mm,and 0.6 mm,respectively.Postoperative neurologic evaluations scores of unified Parkinson's disease rating scale(UPDRS) for Parkinson's disease and Burke-Fahn-Marsden Dystonia Rating Scale(BFMDRS) for dystonia patients improved significantly compared to the preoperative scores(P<0.001); Complications occurred in 10.1%(8/79) patients,and main side effects were dysarthria and diplopia.Conclusion Target positioning by preoperative CT/MRI image fusion technique in deep brain stimulation has high accuracy and good clinical outcomes.
基金part of an ongoing project of the National Important Industry Technological Development Project (High Precision 3D Seismic Technology of Coal Resources of Western China)the financial support from the National Basic Research Program of China (No.2009CB 219603)the National Key Scientific and Technological Project of China (No.2008ZX05035-005-003HZ)
文摘With the objective of establishing the necessary conditions for 3D seismic data from mountainous areas in western China, we compared the application results of wave impedance technology in the lithology and exploration of coal fields. First, we introduce principles and features of three kinds of inversion methods. i.e., Model-Based Inversion, Constrained Sparse Spike Inversion (CSSI) and Geology-Seismic Feature Inversion. Secondly, these inversion methods are contrasted in their application to 3D seismic data from some coalfields in western China. The main information provided by the research includes: improving the vertical resolution of coal deposit strata, inferring lateral variation of the lithology and predicting coal seams and their roof lithology. Finally, the comparison between the three methods shows that the model-based inversion has the higher resolution, while CSSI inversion has better waveform continuity. The geology-seismic feature inversion requires information from a large number of wells and many types of logging curves of good quality. All three methods can meet the requirements of seismic exploration for lithological exploration in coal fields.
基金supported by the Science Foundation of Guizhou Province of China (No. 20177283)the Special Program for Academic Foster and Innovation research of Guizhou University of China (No. 20175788)
文摘The coal mine roof rating(CMRR) is a measure of roof quality or structure competency for bedded roof types typically of underground coal mines. The CMRR has been used widely in the US, South Africa,Canada and Australia. In order to investigate the application of the CMRR system in Chinese coal mines,two coal mines in China located in Panjiang Coal Field in Guizhou Province were investigated. Field data were collected which is required to calculate the CMRR value based on underground exposure. The CMRR values of 11 locations in two coal mines were calculated. The investigations demonstrated that the chance of mine roof failure is very low if the CMRR value is more than 50, given adequate support is installed in mine. It was found that the CMRR guideline are useful to preliminarily investigate stability in Panjiang Coal Field mines.
基金Project(2007CB714202) supported by the National Key Basic Research Program of ChinaProject(SLDRCE10-B-07) supported by theMinistry of Science and Technology of China
文摘An element coupling model (ECM) method was proposed to simulate the global behavior and local damage of a structure.In order to reflect the local damage and improve the computational efficiency,three-dimensional (3D) solid elements and one-dimensional (1D) beam element were coupled by the multi-point constraint equations.A reduced scale 1?8 model test was simulated by the ECM and a full three dimensional model (3DM) contrastively.The results show that the global behavior and local damages of ECM agree well with the test and 3DM.It is indicated that the proposed method can be used in the structural nonlinear analysis accurately and efficiently.
文摘The configuration principles and functions of the non-contact three-dimensional (3D) body measurement system (BMS) developed by the Textile/Clothing Technology Corporation ([TC]^2) are described in this paper. The advantages of this new system, compared with traditional contact body measurement instruments ( Martin instruments ) are discussed by selecting 40 female undergraduates of Donghna University as the scan objects. In the experiments both the Martin instruments and [TC]^2 BMS were used respectively. According to the data of different position (Bust Circumference, Full Waist, Full Hips, Bust Height, Front Waist Height and Back Waist Height) obtained from both of the methods we can get the correlation coefficient which is close to 1, indicating that the results of both methods have comparability. Finally some suggestions for the further applications of the non-contact BMS in the apparel development of China are given.
文摘After the nuclear power plant accident in Japan, Korean government has set the national goal to produce the electricity by renewable energy sources up to 11% by 2035 which is not easy to achieve without ocean energy development. The demand on the clean energy supply has been increased recently and there are many renewable energy development projects and plans announced worldwide. The ocean energy can be produced from tidal current, wave, tidal barrage and ocean thermal sources. The first step is to estimate the resource assessment for each energy source. There are several assessment methods introduced from IEA (International Energy Agency), IRENA (International Renewable Energy Agency), NREL (National Renewable Energy Laboratory), EU ERENE (European Community for Renewable Energy), Bonn University, DLR (German Aerospace Center), etc.. Even these known methods have some sort of similarity; there are different definitions and classifications among them. In this paper, the four-step energy potentials are defined and introduced as theoretical, geographical, technical and market potentials. The theories for each step are presented for ocean energies together with clear definitions. As the tidal current energy research and development are active in Korea having very strong tidal current speed along the west and south coastal regions, the detail procedure for each step of energy potential assessment is introduced for tidal current energy. The paper will illustrate the case study of tidal current power assessment in western coastal region, South Korea with highlighting the key aspects in determining the resource potentials.
基金supported by the Grant Agency of Charles University (43-258020)the Czech Science Foundation (250/09/1244)the Institute of Rock Structure and Mechanics AS CR, v.v.i. (A VOZ30460519)
文摘This study emphasizes the advantage of tectonic phase separation in determination of a tectonic evolution of complicated fault zones. The research focused on the Sudetic Marginal Fault Zone(SMFZ) –a 250 km long active fault zone with documented intraplate seismicity situated on the NE margin of the Bohemian Massif(the Czech Republic). The tectonic history of the SMFZ as well as its kinematic development has been rather complicated and not quite understood. A field structural investigation was carried out in extensive surroundings of the fault zone. The fault-slip data were collected in a number of natural outcrops and quarries with the aim at establishing a robust and field-constrained model for local brittle structural evolution of the studied area. A paleostress analysis was calculated using the collected fault-slip data inversion. The T-Tecto software was utilized for semiautomatic separation of the paleostress phases. Simultaneously three methods of data separation were employed:(1) the Gauss inverse method,(2) the Visualization of Gauss object Function, and(3) the frequency analysis. Within the fault zone multiphase movements were observed on various types of faults as well as wide range of the kinematic indicators orientations. The frequency analysis confirmed the multiphase history of the SMFZ. The calculated tectonic phases were divided according to their relative age as constrained by cross cutting relationships and, where observed, multiple striations on a single fault plane and classified from the oldest to the younger. Data separation and inversion usingT-Tecto software with the Gauss inverse method revealed four different stress phases which are 3 strike-slip stress regimes and one compressional regime. The strike-slip regimes are characterized by σ1 trending NW-SE(43), NNE-SSW(18), ENE-WSW(76) and the compressional one by σ1 trending W-E(26). First, compression occurred parallel to the SMFZ supposedly during the Variscan period. Second, compression at an angle of 60° to general direction of the SMFZ yielded right-lateral movement along the fault zone. This is considered to have occurred during the late-Variscan and post-Variscan period. Third, compression in the W-E direction with almost vertical extension led to reverse movement along the fault zone. This is considered to have occurred during Cenozoic. Fourth, compression almost perpendicular to the SMFZ led to left-lateral transpression along the SMFZ. This is considered to have occurred during Quaternary.
基金Projects(51475464,51175500,51575519)supported by the National Natural Science Foundation of China
文摘As an alternative power source for hybrid electrical vehicle(HEV), electric generating system(EGS) driven by sphere cam engine(SCE) is said to own higher power density and integration. In this work, the structure and working principle of EGS were introduced, based on which the advantages of EGS were displayed. The profile of sphere cam was achieved after the desired motion of piston was given. After establishing the dynamic model of power transmission mechanism, the characteristics of cam-roller mechanism were studied. The results show that the optimal cam profile of SCE is a sinusoid curve which has two peaks and two valleys and a mean pressure angle of 47.19°. Because of the special cam shape, the trace of end surface center of piston is an eight-shape curve on a specific sphere surface. SCE running at speed of 3000 r/min can generate the power of 33.81 kW, which could satisfy the need of HEVs. However, the force between cylinder and piston skirt caused by Coriolis acceleration can reach up to 1182 N, which leads to serious wear between cylinder liner and piston skirt and may shorten the lifespan of SCE.
基金the National Natural Science Foundation of China (No. 51304209)the Basic Research Program of Jiangsu Province (Natural Science Foundation) (No. BK20130179)
文摘Serious shaft lining failures often occur when shaft linings are constructed by passing them through the deep topsoil of Quaternary strata. This approach also leads to the formation of an aquifer at the bottom.Based on the theory of the additional stress which is the main reason for these failures, this study focuses on the treatment effect of underground continuous impervious curtain(UCIC) in terms of different factors, namely, the location, shape, range, and width, by using numerical simulation. Results show that the UCIC can reduce the stress concentration in the shaft lining formed in the bottom aquifer. The UCIC can also reinforce the shaft lining at different angles and can be applied in actual situations. The strength factors of the inner surface of the shaft lining increase after the UCIC are used. The material strength and width of the UCIC show an obvious effect on the stability of the shaft lining. Results proved that the UCIC could effectively strengthen the stability of the shaft lining when it was built in the aquifer or built in the aquifer and above and below the layer.
基金Supported by the National Natural Science Foundation of China(61273160)the Fundamental Research Funds for the Central Universities(14CX06067A,13CX05021A)
文摘In soft sensor field, just-in-time learning(JITL) is an effective approach to model nonlinear and time varying processes. However, most similarity criterions in JITL are computed in the input space only while ignoring important output information, which may lead to inaccurate construction of relevant sample set. To solve this problem, we propose a novel supervised feature extraction method suitable for the regression problem called supervised local and non-local structure preserving projections(SLNSPP), in which both input and output information can be easily and effectively incorporated through a newly defined similarity index. The SLNSPP can not only retain the virtue of locality preserving projections but also prevent faraway points from nearing after projection,which endues SLNSPP with powerful discriminating ability. Such two good properties of SLNSPP are desirable for JITL as they are expected to enhance the accuracy of similar sample selection. Consequently, we present a SLNSPP-JITL framework for developing adaptive soft sensor, including a sparse learning strategy to limit the scale and update the frequency of database. Finally, two case studies are conducted with benchmark datasets to evaluate the performance of the proposed schemes. The results demonstrate the effectiveness of LNSPP and SLNSPP.
基金Supported by the National Natural Science Foundation of China under Grant No.(50579023).
文摘The cylindrical shell is one of the main structural parts in ocean engineering structures.These cylinders are mostly of medium length,which means that the radius of the cross section is significantly smaller than the length of the cylindrical shell.From the viewpoint of the shell theory,they belong to the mid-long cylindrical shell category.To solve mechanical problems on this kind of structure,especially a cracked cylindrical shell,analysis based on shell theory is necessary.At present the generally used solving system for the mid-long cylindrical shell is too complicated,difficult to solve,and inapplicable to engineering.This paper introduced the Sanders' mid-long cylindrical shell theory which reduces the difficulty of the solution process,and will be suitable for solving problems with complicated boundary conditions.On this basis,the engineering applications of this theory were discussed in conjunction with the problem of a mid-long cylindrical shell having a circumferential crack.The solution process is simple,and the closed form solution can usually be found.In practical engineering applications,it gives satisfactory precision.