Currently,the link prediction algorithms primarily focus on studying the interaction between nodes based on chain structure and star structure,which predominantly rely on low-order structural information and do not ex...Currently,the link prediction algorithms primarily focus on studying the interaction between nodes based on chain structure and star structure,which predominantly rely on low-order structural information and do not explore the multivariate interactions between nodes from the perspective of higher-order structural information present in the network.The cycle structure is a higher-order structure that lies between the star and clique structures,where all nodes within the same cycle can interact with each other,even in the absence of direct edges.If a node is encompassed by multiple cycles,it indicates that the node interacts and associates with a greater number of nodes in the network,and it means the node is more important in the network to some extent.Furthermore,if two nodes are included in multiple cycles,it signifies the two nodes are more likely to be connected.Therefore,firstly,a multi-information fusion node importance algorithm based on the cycle structure information is proposed,which integrates both high-order and low-order structural information.Secondly,the obtained integrated structure information and node feature information is regarded as the input features,a two-channel graph neural network model is designed to learn the cycle structure information.Then,the cycle structure information is utilised for the task of link prediction,and a graph neural link predictor with multi-information interactions based on the cycle structure is developed.Finally,extensive experimental validation and analysis show that the node ranking result of the proposed node importance index is more consistent with the actual situation,the proposed graph neural network model can effectively learn the cycle structure information,and using higher-order structural information—cycle information proves to significantly enhance the overall link prediction performance.展开更多
A buckling-restrained steel plate shear wall(BRSPSW)structure with butterfly-shaped links on the lateral sides is introduced to improve the cooperative perfor-mance between the BRSPSW and the boundary frames.A one-spa...A buckling-restrained steel plate shear wall(BRSPSW)structure with butterfly-shaped links on the lateral sides is introduced to improve the cooperative perfor-mance between the BRSPSW and the boundary frames.A one-span two-story concrete-filled steel tube(CFT)column frame specimen equipped with lateral-side butterfly-shaped linked BRSPSWs(LBL-BRSPSWs)is evaluated under low-cycle reversed loading.A finite element(FE)model is developed and validated based on the test results.This FE model accurately simulates the failure modes and load-dis-placement curves.Parametric analyses are conducted on the butterfly-shaped links.The results show that the interactions between the CFT column frame and LBL-BRSPSWs are sig-nificantly influenced by the width ratio of the butterfly-shaped links,while the taper ratio and aspect ratio have relatively minor influences.Compared with traditional steel shear walls with four-sided connections,LBL-BRSPSWs reduce the additional axial forces and bending moments in the frame columns by 28%to 73%and 17%to 87%,respectively,with only a 9%to 30%decrease in the lateral resistance.The experimental and parametric analysis results indicate that setting butterfly-shaped links on the lateral sides of BRSPSWs can significantly enhance their cooperative performance with the boundary frame.The butterfly-shaped link width ratio has a linear relationship with the lateral-resistance performance of the specimens and the additional internal forces in the frame columns.To ensure that LBL-BRSPSW fails prior to the column frames,the link width ratio should be optimized.展开更多
A water soluble crude polysaccharide has been isolated from the fruiting body of cultivated Cordyceps militarvs(L.) Link. The GC analysis indicated that it contained the monosaccharides of Gal, Man, Glc and GlcA. Thei...A water soluble crude polysaccharide has been isolated from the fruiting body of cultivated Cordyceps militarvs(L.) Link. The GC analysis indicated that it contained the monosaccharides of Gal, Man, Glc and GlcA. Their molar ratio is 1 00∶1 58∶7 89∶0 19. The crude polysaccharide was fractionated with ethanol to get three fractions, which were CM Ⅰ, CM Ⅱ and CM Ⅲ. CM Ⅱ was further purified to get one homogeneous fraction named CMB. The molecular weight was estimated to be 60000 by means of gel filtration. CMB is a greyish white powder. The GC analysis indicated that it was composed of Gal, Man, Glc and the molar ratio is 1 00∶1 38∶5 10. Partial hydrolysis with an acid, periodate oxidation, Smith degradation, IR, GC and methylation analyses, GC/MS analyses were used for the structure analyses of CMB. The results reveal that CMB is of a lower branched structure. The main chain is composed of (1→6) linked Man, (1→6) linked Glc, (1→4) linked Glc and (1→4) linked Gal. Some of (1→4) linked Glc and all (1→4) linked Gal residues are substituted at 3 O and 6 O respectively. (1→4) Linked Glc residues without branch probably exist with other monosaccharides alternately. On an average, there is one branch every ten hexose residues. The side chain is composed of major (1→4) linked Glc and minor (1→6) linked Glc. The nonreduced end is composed of Gal and Glc. The main glycosidic link of CMB is α configuration.展开更多
The paper deals with the dynamic response prediction of the composite structure,which consists of two linear components coupled by some nonlinear vibration isolators. Based on the measured impulse response functions o...The paper deals with the dynamic response prediction of the composite structure,which consists of two linear components coupled by some nonlinear vibration isolators. Based on the measured impulse response functions of the linear components, three kinds of dynamic equations of interfacial integration are proposed and a procedure to transform the dynamic equations of integral type into a set of ordinary differential equations is suggested. Computer simulations and a real test are given to verify the effectiveness of the theoretical results.展开更多
Cross-linked polyethylene (PEX) pipes used in hot water supply are required for high mechanical strength and high creep resistance at high temperature. Especially PEX-a pipes which are made by peroxide cross-linking h...Cross-linked polyethylene (PEX) pipes used in hot water supply are required for high mechanical strength and high creep resistance at high temperature. Especially PEX-a pipes which are made by peroxide cross-linking have better performance, such as creep resistance and thermal shock resistance than the pipes made by the other cross-linking method. Because the PEX-a pipes indicate the higher cross-link degree as compared with the other PEX pipes. In this study, the PEX-a pipes which were mixed with several stabilizers were tested to evaluate the effects on cross-link degree and the oxygen induction time. And also they are evaluated with the chlorine aqueous solution by the performance of the long-term hydrostatic pressure test and the long-term hydro dynamic pressure test. As a result, it was found that the combination of antioxidants for PEX-a pipes plays an important role to prolong the oxygen induction time without inhibiting the cross-linking. From the results of the 1H pulsed NMR measurement over the melting point of polyethylene, it was found that each peroxide PEX pipe with different antioxidant combinations indicated the different proportion and crosslink density of cross-linked region, in addition, that these pipes had the effective structure of cross-linking for the hydrostatic and hydrodynamic pressure test with the chlorine aqueous solution. Therefore, it was considered to be useful results for studies of the stricture of cross-linking of polyethylene.展开更多
Reaction of dimers of (R) thionophosphine sulfide (R = P - C6H4OMe,SMe ) with Co, (CO), yields the novel hexacobalt cluster [Co'(μ3, -S)2, (CO) 14 (μ4 -μ4- and the trinuclear clusterPSCH,)J 2' In 1, tw0 Co3...Reaction of dimers of (R) thionophosphine sulfide (R = P - C6H4OMe,SMe ) with Co, (CO), yields the novel hexacobalt cluster [Co'(μ3, -S)2, (CO) 14 (μ4 -μ4- and the trinuclear clusterPSCH,)J 2' In 1, tw0 Co3S(C0)7 units linked by a novel phosphido-thio1ato bifunc-tiona1 bridging p'-SPR ligand as backbone.展开更多
This paper presents a new concept for enhancing the seismic ductility and damping capacity of diagrid structural frames by using shear-link fuse devices and its seismic performance is assessed through nonlinear static...This paper presents a new concept for enhancing the seismic ductility and damping capacity of diagrid structural frames by using shear-link fuse devices and its seismic performance is assessed through nonlinear static and dynamic analysis. The architectural elegancy of the diagrid structure attributed to its triangular leaning member configuration and high structural redundancy make this system a desirable choice for tall building design. However, forming a stable energy dissipation mechanism in diagrid framing remains to be investigated to expand its use in regions with high seismicity. To address this issue, a diagrid framing design is proposed here which provides a competitive design option in highly seismic regions through its increased ductility and improved energy dissipation capacity provided by replaceable shear links interconnecting the diagonal members at their ends.The structural characteristics and seismic behavior （capacity, stiffness, energy dissipation, ductility） of the diagrid structural frame are demonstrated with a 21-story building diagrid frame subjected to nonlinear static and dynamic analysis. The findings from the nonfinear time history analysis verify that satisfactory seismic performance can be achieved by the proposed diagrid frame subjected to design basis earthquakes in California. In particular, one appealing feature of the proposed diagrid building is its reduced residual displacement after strong earthquakes.展开更多
The reduction approaches are presented for vibration control of symmetric, cyclic periodic and linking structures. The condensation of generalized coordinates, the locations of sensors and actuators, and the relation ...The reduction approaches are presented for vibration control of symmetric, cyclic periodic and linking structures. The condensation of generalized coordinates, the locations of sensors and actuators, and the relation between system inputs and control forces are assumed to be set in a symmetric way so that the control system posses the same repetition as the structure considered. By employing proper transformations of condensed generalized coordinates and the system inputs, the vibration control of an entire system can be implemented by carrying out the control of a number of sub-structures, and thus the dimension of the control problem can be significantly reduced.展开更多
The shifting requirements as imposed on operations ma nagement require adjusting and tailoring the organisational structure to meet ma rket demands. However, translating these requirements directly into hierarchical s...The shifting requirements as imposed on operations ma nagement require adjusting and tailoring the organisational structure to meet ma rket demands. However, translating these requirements directly into hierarchical structure will not ensure the integration of processes across organisational un its and guarantee desirable performance. Therefore, management and management li terature wonders: · How should we connect processes to the external environment within a strategi c framework · Which organisational structures do meet performance requirements · Which choices and freedom do we have within organisational structures · How and when do we implement organisational structures That the hierarchical structure does not meet as such the performance requiremen ts nor did it relate to these became already clear during case studies performed in the ’70s. The conclusion was drawn that organisational changes should affect working processes before they proof to be viable. This required the development of new approach through empirical studies and base d on literature. This led to the development of the organelle structure. The org anelle structure should connect to the strategy and the product flow. Thereto, a decision model has been developed for revealing these relations and the practic al implication. During a number of case studies this methodology has been refined and includes t he strategic choice between variants for the organelle structure with their own performance capabilities; we distinguish about 20 variants ranging between the f unctional organisation and the product flow organisation. These ranges of choice s however can be connected to different order entry points, stemming from logist ic concepts. This extends the performance to improved lead-times and improved c ontrol. Strategic choices relate the organelle structure to external performance criteria dictated by product/market-combinations: · lead-time · quality · costs and internal choices for performance criteria: · flexibility · productivity · resource utilisation · innovative performance. Case studies reveal the drastic improvements of the performance of operations an d manufacturing. The paper will discuss a few of these implementations to demons trate the impact. They also show how one derives the hierarchical structure from the choice for the organelle structure. Organelle structures do bridge the link of an industrial company to its environm ent and the internal possibilities, dictated by characteristics of product flow and process execution. The link to the environment results in a strategic framew ork for assessment of alternatives and possibilities. Choices for organelle stru ctures depend strongly on choices on the order entry points of the hardware flow and the specification flow. The evaluation of the characteristics takes place a gainst the strategic framework ensuring competitive advantage as well as a high probability of factual implementation and performance improvement.展开更多
This paper reviews several recently-developed techniques for the minimum-cost optimal design of water-retaining structures (WRSs), which integrate the effects of seepage. These include the incorporation of uncertainty...This paper reviews several recently-developed techniques for the minimum-cost optimal design of water-retaining structures (WRSs), which integrate the effects of seepage. These include the incorporation of uncertainty in heterogeneous soil parameter estimates and quantification of reliability. This review is limited to methods based on coupled simulation-optimization (S-O) models. In this context, the design of WRSs is mainly affected by hydraulic design variables such as seepage quantities, which are difficult to determine from closed-form solutions or approximation theories. An S-O model is built by integrating numerical seepage modeling responses to an optimization algorithm based on efficient surrogate models. The surrogate models (meta-models) are trained on simulated data obtained from finite element numerical code solutions. The proposed methodology is applied using several machine learning techniques and optimization solvers to optimize the design of WRS by incorporating different design variables and boundary conditions. Additionally, the effects of several scenarios of flow domain hydraulic conductivity are integrated into the S-O model. Also, reliability based optimum design concepts are incorporated in the S-O model to quantify uncertainty in seepage quantities due to uncertainty in hydraulic conductivity estimates. We can conclude that the S-O model can efficiently optimize WRS designs. The ANN, SVM, and GPR machine learning technique-based surrogate models are efficiently and expeditiously incorporated into the S-O models to imitate the numerical responses of simulations of various problems.展开更多
A one dimensional bimetallic compound ｛〔CuCd(pba)(H 2O) 3〕·2H 2O｝ n in which pba was propylenebis (oxamic acid), was prepared. Crystal structure of the title compound was determined. It belongs to orthorhombi...A one dimensional bimetallic compound ｛〔CuCd(pba)(H 2O) 3〕·2H 2O｝ n in which pba was propylenebis (oxamic acid), was prepared. Crystal structure of the title compound was determined. It belongs to orthorhombic system, molecular formula CuCdC 7H 16 N 2O 11 , M r =480.17, space group Pnma(#62), a=12.953(2), b=21 626(6), c=5.253(3), V=1471(2) 3 and D x =2.17g/cm 3 for Z =4. The structure was solved by direct methods with final R =0.052 and R w =0.063 for 1055 observed reflections with I>3σ(I ). Two nitrogen atoms and two oxygen atoms from the oxamide and a water molecule coordinated to the Cu II ion forming a square pyramidal geometry. Four oxygen atoms from the oxamide and two water molecules coordinated to the Cd II ion forming an elongated octahedral geometry.展开更多
The present investigation is motivated by finding and developing an easily understandable solution in the context of unified quantum and gravitational theories. Model-based methods are applied, with emphasis on struct...The present investigation is motivated by finding and developing an easily understandable solution in the context of unified quantum and gravitational theories. Model-based methods are applied, with emphasis on structural descriptions by introducing some strong hypotheses. A subset of the introduced hypotheses led to a surprising understanding of the internal structure and construction of quarks, neutrons, protons and more complex atomic nuclei. The research work therefore focused mainly on the model-based interpretation of subatomic processes. The results obtained so far and presented in this paper are new. They consist of a generic description model for the structure of atomic nuclei. This model contains two important structural links that originate from the initial phase of the cosmological big bang. They hold atomic parts together and are involved in many known nuclear fusion and fission processes. Modifications of them, including the electron-positron annihilation process, are necessary and will be described. A new interpretation of the strong forces from the Standard Model is possible and will be given. In addition, the formation processes for electron and positron particles are considered. Based on the structural relationships, a deeper understanding of matter transformations (transmutations), early cosmological processes and dark matter has been achieved. All challenges of this work are the logical conclusions from the used hypotheses on two structural links. They need to be further investigated and verified by theoretical and experimental works. The postulated particle in this paper, as accompanying product in the electron-positron annihilation, will play a major role for the future investigations.展开更多
The topological structures of the vortex filaments and vortex tubes with an exact solution of a straight spiral vortex tube are discussed. It is found that there are some confusions about the calculation of the helic...The topological structures of the vortex filaments and vortex tubes with an exact solution of a straight spiral vortex tube are discussed. It is found that there are some confusions about the calculation of the helicity of a knotted vortex filament and some linked vortex filaments by using different methods. How to unify these methods is explained and the right results are given. (Edited author abstract) 5 Refs.展开更多
Network information mining is the study of the network topology,which may answer a large number of applicationbased questions towards the structural evolution and the function of a real system.The question can be rela...Network information mining is the study of the network topology,which may answer a large number of applicationbased questions towards the structural evolution and the function of a real system.The question can be related to how the real system evolves or how individuals interact with each other in social networks.Although the evolution of the real system may seem to be found regularly,capturing patterns on the whole process of evolution is not trivial.Link prediction is one of the most important technologies in network information mining,which can help us understand the evolution mechanism of real-life network.Link prediction aims to uncover missing links or quantify the likelihood of the emergence of nonexistent links from known network structures.Currently,widely existing methods of link prediction almost focus on short-path networks that usually have a myriad of close triangular structures.However,these algorithms on highly sparse or longpath networks have poor performance.Here,we propose a new index that is associated with the principles of structural equivalence and shortest path length(SESPL)to estimate the likelihood of link existence in long-path networks.Through a test of 548 real networks,we find that SESPL is more effective and efficient than other similarity-based predictors in long-path networks.Meanwhile,we also exploit the performance of SESPL predictor and of embedding-based approaches via machine learning techniques.The results show that the performance of SESPL can achieve a gain of 44.09%over GraphWave and 7.93%over Node2vec.Finally,according to the matrix of maximal information coefficient(MIC)between all the similarity-based predictors,SESPL is a new independent feature in the space of traditional similarity features.展开更多
Chitosan (CS) microparticles with and without cross-linking were prepared by a water-in-oil emulsion solvent diffusion method without any surfactants. Aqueous CS solution and ethyl ace- tate were used as water and oil...Chitosan (CS) microparticles with and without cross-linking were prepared by a water-in-oil emulsion solvent diffusion method without any surfactants. Aqueous CS solution and ethyl ace- tate were used as water and oil phases, respectively. Genipin was used as a cross-linker. Influ- ences of genipin ratios and cross-linking times on CS microparticle characteristics were investigated. Non-cross-linked and cross-linked CS microparticles were spherical in shape and rough in surface. Microparticle matrices showed porous structures. Surface roughness, mean par- ticle sizes and bulk density of CS microparticles increased and their dissolutions in acetic acid solution decreased when genipin ratio and cross- linking time increased.展开更多
The lsolobal displacement reaction between the dianion {M(CO)3[(h5-C5H4) C(O)C6H4C(O)(h5-C5H4)](CO)3M}2- and two molecules of [(m3-C)CO2Et]Co3(CO)9 gave rise to the formation of terephthaloyl(biscyclopentadienyl)-brid...The lsolobal displacement reaction between the dianion {M(CO)3[(h5-C5H4) C(O)C6H4C(O)(h5-C5H4)](CO)3M}2- and two molecules of [(m3-C)CO2Et]Co3(CO)9 gave rise to the formation of terephthaloyl(biscyclopentadienyl)-bridged double cluster complexes [(h5-C5H4)C(O)C6H4C(O)(h5-C5H4)]{[(m3-C)CO2Et]Co2M(CO)8}2 (M = Mo 1, M = W, 2). In the reaction, single cluster complexes[(m3-C)CO2Et]-Co2M(CO)8[h5-C5H4C(O)C6H4CO2CH3] ( M = Mo 3, M = W, 4) were yielded as by-products. All the cluster complexes were characterized by C/H analysis, IR and 1H NMR spectroscopy, and the structure of 3 has been determined by single-crystal X-ray diffraction method. Crystal data: Mr = 750.19, monoclinic, space group P21/c, a = 22.652(5), b = 8.954 (2), c = 14.530(3) ? b = 104.00(3), V = 2859.6(10) 懦, Z = 4, Dc = 1.743 mg/m? F(000) = 1488, m = 1.644 mm-1, the final R = 0.0555 and wR = 0.1353 for 5519 observations with I > 2s(I).展开更多
基金National Key Research and Development Program of China,Grant/Award Number:2020YFC1523300Construction of Innovation Platform Program of Qinghai Province of China,Grant/Award Number:2022-ZJ-T02。
文摘Currently,the link prediction algorithms primarily focus on studying the interaction between nodes based on chain structure and star structure,which predominantly rely on low-order structural information and do not explore the multivariate interactions between nodes from the perspective of higher-order structural information present in the network.The cycle structure is a higher-order structure that lies between the star and clique structures,where all nodes within the same cycle can interact with each other,even in the absence of direct edges.If a node is encompassed by multiple cycles,it indicates that the node interacts and associates with a greater number of nodes in the network,and it means the node is more important in the network to some extent.Furthermore,if two nodes are included in multiple cycles,it signifies the two nodes are more likely to be connected.Therefore,firstly,a multi-information fusion node importance algorithm based on the cycle structure information is proposed,which integrates both high-order and low-order structural information.Secondly,the obtained integrated structure information and node feature information is regarded as the input features,a two-channel graph neural network model is designed to learn the cycle structure information.Then,the cycle structure information is utilised for the task of link prediction,and a graph neural link predictor with multi-information interactions based on the cycle structure is developed.Finally,extensive experimental validation and analysis show that the node ranking result of the proposed node importance index is more consistent with the actual situation,the proposed graph neural network model can effectively learn the cycle structure information,and using higher-order structural information—cycle information proves to significantly enhance the overall link prediction performance.
基金The National Key Research and Development Program of China(No.2023YFC3805005)Shanghai Municipal Science and Technology Commission Research Program(No.22DZ1201404).
文摘A buckling-restrained steel plate shear wall(BRSPSW)structure with butterfly-shaped links on the lateral sides is introduced to improve the cooperative perfor-mance between the BRSPSW and the boundary frames.A one-span two-story concrete-filled steel tube(CFT)column frame specimen equipped with lateral-side butterfly-shaped linked BRSPSWs(LBL-BRSPSWs)is evaluated under low-cycle reversed loading.A finite element(FE)model is developed and validated based on the test results.This FE model accurately simulates the failure modes and load-dis-placement curves.Parametric analyses are conducted on the butterfly-shaped links.The results show that the interactions between the CFT column frame and LBL-BRSPSWs are sig-nificantly influenced by the width ratio of the butterfly-shaped links,while the taper ratio and aspect ratio have relatively minor influences.Compared with traditional steel shear walls with four-sided connections,LBL-BRSPSWs reduce the additional axial forces and bending moments in the frame columns by 28%to 73%and 17%to 87%,respectively,with only a 9%to 30%decrease in the lateral resistance.The experimental and parametric analysis results indicate that setting butterfly-shaped links on the lateral sides of BRSPSWs can significantly enhance their cooperative performance with the boundary frame.The butterfly-shaped link width ratio has a linear relationship with the lateral-resistance performance of the specimens and the additional internal forces in the frame columns.To ensure that LBL-BRSPSW fails prior to the column frames,the link width ratio should be optimized.
文摘A water soluble crude polysaccharide has been isolated from the fruiting body of cultivated Cordyceps militarvs(L.) Link. The GC analysis indicated that it contained the monosaccharides of Gal, Man, Glc and GlcA. Their molar ratio is 1 00∶1 58∶7 89∶0 19. The crude polysaccharide was fractionated with ethanol to get three fractions, which were CM Ⅰ, CM Ⅱ and CM Ⅲ. CM Ⅱ was further purified to get one homogeneous fraction named CMB. The molecular weight was estimated to be 60000 by means of gel filtration. CMB is a greyish white powder. The GC analysis indicated that it was composed of Gal, Man, Glc and the molar ratio is 1 00∶1 38∶5 10. Partial hydrolysis with an acid, periodate oxidation, Smith degradation, IR, GC and methylation analyses, GC/MS analyses were used for the structure analyses of CMB. The results reveal that CMB is of a lower branched structure. The main chain is composed of (1→6) linked Man, (1→6) linked Glc, (1→4) linked Glc and (1→4) linked Gal. Some of (1→4) linked Glc and all (1→4) linked Gal residues are substituted at 3 O and 6 O respectively. (1→4) Linked Glc residues without branch probably exist with other monosaccharides alternately. On an average, there is one branch every ten hexose residues. The side chain is composed of major (1→4) linked Glc and minor (1→6) linked Glc. The nonreduced end is composed of Gal and Glc. The main glycosidic link of CMB is α configuration.
文摘The paper deals with the dynamic response prediction of the composite structure,which consists of two linear components coupled by some nonlinear vibration isolators. Based on the measured impulse response functions of the linear components, three kinds of dynamic equations of interfacial integration are proposed and a procedure to transform the dynamic equations of integral type into a set of ordinary differential equations is suggested. Computer simulations and a real test are given to verify the effectiveness of the theoretical results.
文摘Cross-linked polyethylene (PEX) pipes used in hot water supply are required for high mechanical strength and high creep resistance at high temperature. Especially PEX-a pipes which are made by peroxide cross-linking have better performance, such as creep resistance and thermal shock resistance than the pipes made by the other cross-linking method. Because the PEX-a pipes indicate the higher cross-link degree as compared with the other PEX pipes. In this study, the PEX-a pipes which were mixed with several stabilizers were tested to evaluate the effects on cross-link degree and the oxygen induction time. And also they are evaluated with the chlorine aqueous solution by the performance of the long-term hydrostatic pressure test and the long-term hydro dynamic pressure test. As a result, it was found that the combination of antioxidants for PEX-a pipes plays an important role to prolong the oxygen induction time without inhibiting the cross-linking. From the results of the 1H pulsed NMR measurement over the melting point of polyethylene, it was found that each peroxide PEX pipe with different antioxidant combinations indicated the different proportion and crosslink density of cross-linked region, in addition, that these pipes had the effective structure of cross-linking for the hydrostatic and hydrodynamic pressure test with the chlorine aqueous solution. Therefore, it was considered to be useful results for studies of the stricture of cross-linking of polyethylene.
文摘Reaction of dimers of (R) thionophosphine sulfide (R = P - C6H4OMe,SMe ) with Co, (CO), yields the novel hexacobalt cluster [Co'(μ3, -S)2, (CO) 14 (μ4 -μ4- and the trinuclear clusterPSCH,)J 2' In 1, tw0 Co3S(C0)7 units linked by a novel phosphido-thio1ato bifunc-tiona1 bridging p'-SPR ligand as backbone.
基金the University of Maryland for providing partial financial support for this research project
文摘This paper presents a new concept for enhancing the seismic ductility and damping capacity of diagrid structural frames by using shear-link fuse devices and its seismic performance is assessed through nonlinear static and dynamic analysis. The architectural elegancy of the diagrid structure attributed to its triangular leaning member configuration and high structural redundancy make this system a desirable choice for tall building design. However, forming a stable energy dissipation mechanism in diagrid framing remains to be investigated to expand its use in regions with high seismicity. To address this issue, a diagrid framing design is proposed here which provides a competitive design option in highly seismic regions through its increased ductility and improved energy dissipation capacity provided by replaceable shear links interconnecting the diagonal members at their ends.The structural characteristics and seismic behavior （capacity, stiffness, energy dissipation, ductility） of the diagrid structural frame are demonstrated with a 21-story building diagrid frame subjected to nonlinear static and dynamic analysis. The findings from the nonfinear time history analysis verify that satisfactory seismic performance can be achieved by the proposed diagrid frame subjected to design basis earthquakes in California. In particular, one appealing feature of the proposed diagrid building is its reduced residual displacement after strong earthquakes.
基金Project supported by the National Natural Science Foundation of China (No.60034010) the Australia Research Council Discovery-Projects Grant (No.DP0210716)
文摘The reduction approaches are presented for vibration control of symmetric, cyclic periodic and linking structures. The condensation of generalized coordinates, the locations of sensors and actuators, and the relation between system inputs and control forces are assumed to be set in a symmetric way so that the control system posses the same repetition as the structure considered. By employing proper transformations of condensed generalized coordinates and the system inputs, the vibration control of an entire system can be implemented by carrying out the control of a number of sub-structures, and thus the dimension of the control problem can be significantly reduced.
文摘The shifting requirements as imposed on operations ma nagement require adjusting and tailoring the organisational structure to meet ma rket demands. However, translating these requirements directly into hierarchical structure will not ensure the integration of processes across organisational un its and guarantee desirable performance. Therefore, management and management li terature wonders: · How should we connect processes to the external environment within a strategi c framework · Which organisational structures do meet performance requirements · Which choices and freedom do we have within organisational structures · How and when do we implement organisational structures That the hierarchical structure does not meet as such the performance requiremen ts nor did it relate to these became already clear during case studies performed in the ’70s. The conclusion was drawn that organisational changes should affect working processes before they proof to be viable. This required the development of new approach through empirical studies and base d on literature. This led to the development of the organelle structure. The org anelle structure should connect to the strategy and the product flow. Thereto, a decision model has been developed for revealing these relations and the practic al implication. During a number of case studies this methodology has been refined and includes t he strategic choice between variants for the organelle structure with their own performance capabilities; we distinguish about 20 variants ranging between the f unctional organisation and the product flow organisation. These ranges of choice s however can be connected to different order entry points, stemming from logist ic concepts. This extends the performance to improved lead-times and improved c ontrol. Strategic choices relate the organelle structure to external performance criteria dictated by product/market-combinations: · lead-time · quality · costs and internal choices for performance criteria: · flexibility · productivity · resource utilisation · innovative performance. Case studies reveal the drastic improvements of the performance of operations an d manufacturing. The paper will discuss a few of these implementations to demons trate the impact. They also show how one derives the hierarchical structure from the choice for the organelle structure. Organelle structures do bridge the link of an industrial company to its environm ent and the internal possibilities, dictated by characteristics of product flow and process execution. The link to the environment results in a strategic framew ork for assessment of alternatives and possibilities. Choices for organelle stru ctures depend strongly on choices on the order entry points of the hardware flow and the specification flow. The evaluation of the characteristics takes place a gainst the strategic framework ensuring competitive advantage as well as a high probability of factual implementation and performance improvement.
文摘This paper reviews several recently-developed techniques for the minimum-cost optimal design of water-retaining structures (WRSs), which integrate the effects of seepage. These include the incorporation of uncertainty in heterogeneous soil parameter estimates and quantification of reliability. This review is limited to methods based on coupled simulation-optimization (S-O) models. In this context, the design of WRSs is mainly affected by hydraulic design variables such as seepage quantities, which are difficult to determine from closed-form solutions or approximation theories. An S-O model is built by integrating numerical seepage modeling responses to an optimization algorithm based on efficient surrogate models. The surrogate models (meta-models) are trained on simulated data obtained from finite element numerical code solutions. The proposed methodology is applied using several machine learning techniques and optimization solvers to optimize the design of WRS by incorporating different design variables and boundary conditions. Additionally, the effects of several scenarios of flow domain hydraulic conductivity are integrated into the S-O model. Also, reliability based optimum design concepts are incorporated in the S-O model to quantify uncertainty in seepage quantities due to uncertainty in hydraulic conductivity estimates. We can conclude that the S-O model can efficiently optimize WRS designs. The ANN, SVM, and GPR machine learning technique-based surrogate models are efficiently and expeditiously incorporated into the S-O models to imitate the numerical responses of simulations of various problems.
文摘A one dimensional bimetallic compound ｛〔CuCd(pba)(H 2O) 3〕·2H 2O｝ n in which pba was propylenebis (oxamic acid), was prepared. Crystal structure of the title compound was determined. It belongs to orthorhombic system, molecular formula CuCdC 7H 16 N 2O 11 , M r =480.17, space group Pnma(#62), a=12.953(2), b=21 626(6), c=5.253(3), V=1471(2) 3 and D x =2.17g/cm 3 for Z =4. The structure was solved by direct methods with final R =0.052 and R w =0.063 for 1055 observed reflections with I>3σ(I ). Two nitrogen atoms and two oxygen atoms from the oxamide and a water molecule coordinated to the Cu II ion forming a square pyramidal geometry. Four oxygen atoms from the oxamide and two water molecules coordinated to the Cd II ion forming an elongated octahedral geometry.
文摘The present investigation is motivated by finding and developing an easily understandable solution in the context of unified quantum and gravitational theories. Model-based methods are applied, with emphasis on structural descriptions by introducing some strong hypotheses. A subset of the introduced hypotheses led to a surprising understanding of the internal structure and construction of quarks, neutrons, protons and more complex atomic nuclei. The research work therefore focused mainly on the model-based interpretation of subatomic processes. The results obtained so far and presented in this paper are new. They consist of a generic description model for the structure of atomic nuclei. This model contains two important structural links that originate from the initial phase of the cosmological big bang. They hold atomic parts together and are involved in many known nuclear fusion and fission processes. Modifications of them, including the electron-positron annihilation process, are necessary and will be described. A new interpretation of the strong forces from the Standard Model is possible and will be given. In addition, the formation processes for electron and positron particles are considered. Based on the structural relationships, a deeper understanding of matter transformations (transmutations), early cosmological processes and dark matter has been achieved. All challenges of this work are the logical conclusions from the used hypotheses on two structural links. They need to be further investigated and verified by theoretical and experimental works. The postulated particle in this paper, as accompanying product in the electron-positron annihilation, will play a major role for the future investigations.
基金This work is supported by the National Basic Research Important Project"Nonlinear Science"
文摘The topological structures of the vortex filaments and vortex tubes with an exact solution of a straight spiral vortex tube are discussed. It is found that there are some confusions about the calculation of the helicity of a knotted vortex filament and some linked vortex filaments by using different methods. How to unify these methods is explained and the right results are given. (Edited author abstract) 5 Refs.
基金supported by the National Natural Science Foundation of China(Grant Nos.61773091 and 62173065)the Industry-University-Research Innovation Fund for Chinese Universities(Grant No.2021ALA03016)+2 种基金the Fund for University Innovation Research Group of Chongqing(Grant No.CXQT21005)the National Social Science Foundation of China(Grant No.20CTQ029)the Fundamental Research Funds for the Central Universities(Grant No.SWU119062).
文摘Network information mining is the study of the network topology,which may answer a large number of applicationbased questions towards the structural evolution and the function of a real system.The question can be related to how the real system evolves or how individuals interact with each other in social networks.Although the evolution of the real system may seem to be found regularly,capturing patterns on the whole process of evolution is not trivial.Link prediction is one of the most important technologies in network information mining,which can help us understand the evolution mechanism of real-life network.Link prediction aims to uncover missing links or quantify the likelihood of the emergence of nonexistent links from known network structures.Currently,widely existing methods of link prediction almost focus on short-path networks that usually have a myriad of close triangular structures.However,these algorithms on highly sparse or longpath networks have poor performance.Here,we propose a new index that is associated with the principles of structural equivalence and shortest path length(SESPL)to estimate the likelihood of link existence in long-path networks.Through a test of 548 real networks,we find that SESPL is more effective and efficient than other similarity-based predictors in long-path networks.Meanwhile,we also exploit the performance of SESPL predictor and of embedding-based approaches via machine learning techniques.The results show that the performance of SESPL can achieve a gain of 44.09%over GraphWave and 7.93%over Node2vec.Finally,according to the matrix of maximal information coefficient(MIC)between all the similarity-based predictors,SESPL is a new independent feature in the space of traditional similarity features.
文摘Chitosan (CS) microparticles with and without cross-linking were prepared by a water-in-oil emulsion solvent diffusion method without any surfactants. Aqueous CS solution and ethyl ace- tate were used as water and oil phases, respectively. Genipin was used as a cross-linker. Influ- ences of genipin ratios and cross-linking times on CS microparticle characteristics were investigated. Non-cross-linked and cross-linked CS microparticles were spherical in shape and rough in surface. Microparticle matrices showed porous structures. Surface roughness, mean par- ticle sizes and bulk density of CS microparticles increased and their dissolutions in acetic acid solution decreased when genipin ratio and cross- linking time increased.
基金This work is supported by Natural Science Foundation of China
文摘The lsolobal displacement reaction between the dianion {M(CO)3[(h5-C5H4) C(O)C6H4C(O)(h5-C5H4)](CO)3M}2- and two molecules of [(m3-C)CO2Et]Co3(CO)9 gave rise to the formation of terephthaloyl(biscyclopentadienyl)-bridged double cluster complexes [(h5-C5H4)C(O)C6H4C(O)(h5-C5H4)]{[(m3-C)CO2Et]Co2M(CO)8}2 (M = Mo 1, M = W, 2). In the reaction, single cluster complexes[(m3-C)CO2Et]-Co2M(CO)8[h5-C5H4C(O)C6H4CO2CH3] ( M = Mo 3, M = W, 4) were yielded as by-products. All the cluster complexes were characterized by C/H analysis, IR and 1H NMR spectroscopy, and the structure of 3 has been determined by single-crystal X-ray diffraction method. Crystal data: Mr = 750.19, monoclinic, space group P21/c, a = 22.652(5), b = 8.954 (2), c = 14.530(3) ? b = 104.00(3), V = 2859.6(10) 懦, Z = 4, Dc = 1.743 mg/m? F(000) = 1488, m = 1.644 mm-1, the final R = 0.0555 and wR = 0.1353 for 5519 observations with I > 2s(I).
