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Thermal Induced Periodic Phase Separation in Polymer Blends
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作者 孙喆 宋海华 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 北大核心 2006年第2期99-101,共3页
Simulations were carried out for studying the periodic phase separation of a symmetric binary polymer blend on the basis of Cahn-Hilliard-Cook theory. The time dependent interaction parameter x(τ) was assumed to un... Simulations were carried out for studying the periodic phase separation of a symmetric binary polymer blend on the basis of Cahn-Hilliard-Cook theory. The time dependent interaction parameter x(τ) was assumed to undergo a step-wise oscillation. The hierarchic structures composed of both large and small domains were obtained. The mechanism of the periodic formation of hierarchic structures was also demonstrated. 展开更多
关键词 Periodic spinodal decomposition Simulations Hierarchic structures
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Trajectory optimization of multiple quad-rotor UAVs in collaborative assembling task 被引量:8
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作者 Chen Yongbo Yu Jianqiao +3 位作者 Mei Yuesong Zhang Siyu Ai Xiaolin Jia Zhenyue 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2016年第1期184-201,共18页
A hierarchic optimization strategy based on the offline path planning process and online trajectory planning process is presented to solve the trajectory optimization problem of multiple quad-rotor unmanned aerial veh... A hierarchic optimization strategy based on the offline path planning process and online trajectory planning process is presented to solve the trajectory optimization problem of multiple quad-rotor unmanned aerial vehicles in the collaborative assembling task. Firstly, the path planning process is solved by a novel parallel intelligent optimization algorithm, the central force optimization-genetic algorithm (CFO-GA), which combines the central force optimization (CFO) algorithm with the genetic algorithm (GA). Because of the immaturity of the CFO, the convergence analysis of the CFO is completed by the stability theory of the linear time-variant discrete-time sys- tems. The results show that the parallel CFO-GA algorithm converges faster than the parallel CFO and the central force optimization-sequential quadratic programming (CFO-SQP) algorithm. Then, the trajectory planning problem is established based on the path planning results. In order to limit the range of the attitude angle and guarantee the fight stability, the optimized object is changed from the ordinary six-degree-of-freedom rigid-body dynamic model to the dynamic model with an inner-loop attitude controller. The results show that the trajectory planning process can be solved by the mature SQP algorithm easily. Finally, the discussion and analysis of the real-time per- formance of the hierarchic optimization strategy are presented around the group number of the wav^oints and the eoual interval time. 展开更多
关键词 Hierarchic optimizationstrategy Parallel CFO-GA algorithm Path planning Six degree-of-freedom rigid-body dynamic model Trajectory optimization Trajectory planning
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A hierarchically structured tin-cobalt composite with an enhanced electronic effect for high-performance CO_(2) electroreduction in a wide potential range 被引量:3
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作者 Xingxing Jiang Xuan Li +5 位作者 Yan Kong Chen Deng Xiaojie Li Qi Hu Hengpan Yang Chuanxin He 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第1期462-469,I0012,共9页
Earth-abundant and nontoxic Sn-based materials have been regarded as promising catalysts for the electrochemical conversion of CO_(2)to C1 products,e.g.,CO and formate.However,it is still difficult for Snbased materia... Earth-abundant and nontoxic Sn-based materials have been regarded as promising catalysts for the electrochemical conversion of CO_(2)to C1 products,e.g.,CO and formate.However,it is still difficult for Snbased materials to obtain satisfactory performance at low-to-moderate overpotentials.Herein,a simple and facile electrospinning technique is utilized to prepare a composite of a bimetallic Sn-Co oxide/carbon matrix with a hollow nanotube structure(Sn Co-HNT).Sn Co-HNT can maintain>90%faradaic efficiencies for C1 products within a wide potential range from-0.6 VRHE to-1.2 VRHE,and a highest 94.1%selectivity towards CO in an H-type cell.Moreover,a 91.2%faradaic efficiency with a 241.3 m A cm^(-2)partial current density for C1 products could be achieved using a flow cell.According to theoretical calculations,the fusing of Sn/Co oxides on the carbon matrix accelerates electron transfer at the atomic level,causing electron deficiency of Sn centers and reversible variation between Co^(2+)and Co^(3+)centers.The synergistic effect of the Sn/Co composition improves the electron affinity of the catalyst surface,which is conducive to the adsorption and stabilization of key intermediates and eventually increases the catalytic activity in CO_(2)electroreduction.This study could provide a new strategy for the construction of oxide-derived catalysts for CO_(2)electroreduction. 展开更多
关键词 Hierarchic structure Tin-cobalt bimetallic oxide Electronic effect CO_(2)electroreduction Wide potential range
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Soil Biological and Biochemical Responses to Cd Exposure 被引量:1
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作者 R. Ebhin Masto Rajkumar Ahirwar +2 位作者 Joshy George L. C. Ram V. A. Selvi 《Open Journal of Soil Science》 2011年第1期8-15,共8页
Heavy metals can stimulate the activity of soil enzymes in smaller amounts, but act as inhibitors if present in high concentrations. Natural and anthropogenic heavy metal contamination and its disturbances on soils ca... Heavy metals can stimulate the activity of soil enzymes in smaller amounts, but act as inhibitors if present in high concentrations. Natural and anthropogenic heavy metal contamination and its disturbances on soils can be evaluated by using enzymatic activities as sensors. To study the effects of Cd, soil added with known Cd concentrations (0, 10, 20, 50,100 and 200 mg/kg soil) were incubated for a period of 30 days at 28℃. At intervals of 0, 5, 10, 20 and 30 days samples were withdrawn for enzyme assays like dehydrogenase (DHA), catalase (CAT), phenol oxidase (PHE), and peroxidise (PER). In a separate experiment the effect of Cd on active microbial biomass carbon (AMBC), basal soil respiration (BSR), and metabolic quotient were studied. AMBC showed a reduction trend with increase in Cd concentration, and a maximum reduction of 47% was observed at 30th day for 200 mg/kg treatment. BSR also has got the same trend, with a maximum decrease of 42% at the 30th day. With the rate of Cd amendments and treatment period, DHA has shown an inhibition trend;whereas maximum decrease was observed for 200 mg/kg treatment at 30th day. CAT, PER, and PHE were found to be increased with Cd addition and remained at higher levels than in the control soil. These changes can be attributed to the effect of Cd on microbial activities. Based on cluster analysis, AMBC appears to be the sensitive indicators for the soil exposed to Cd contamination. 展开更多
关键词 Chemical Elements Dynamics Synergism ANTAGONISM Information Function Hierarchic Order Soil Formation MINERAL SUBSTRATUM
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Stochastic Model for Multiple Classes and Subclasses Simple Documents Processing 被引量:1
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作者 Pierre Moukeli Mbindzoukou Arsène Roland Moukoukou Marius Massala 《Intelligent Information Management》 2021年第2期124-140,共17页
The issue of document management has been raised for a long time, especially with the appearance of office automation in the 1980s, which led to dematerialization and Electronic Document Management (EDM). In the same ... The issue of document management has been raised for a long time, especially with the appearance of office automation in the 1980s, which led to dematerialization and Electronic Document Management (EDM). In the same period, workflow management has experienced significant development, but has become more focused on the industry. However, it seems to us that document workflows have not had the same interest for the scientific community. But nowadays, the emergence and supremacy of the Internet in electronic exchanges are leading to a massive dematerialization of documents;which requires a conceptual reconsideration of the organizational framework for the processing of said documents in both public and private administrations. This problem seems open to us and deserves the interest of the scientific community. Indeed, EDM has mainly focused on the storage (referencing) and circulation of documents (traceability). It paid little attention to the overall behavior of the system in processing documents. The purpose of our researches is to model document processing systems. In the previous works, we proposed a general model and its specialization in the case of small documents (any document processed by a single person at a time during its processing life cycle), which represent 70% of documents processed by administrations, according to our study. In this contribution, we extend the model for processing small documents to the case where they are managed in a system comprising document classes organized in subclasses;which is the case for most administrations. We have thus observed that this model is a Markovian <i>M<sup>L×K</sup>/M<sup>L×K</sup>/</i>1 queues network. We have analyzed the constraints of this model and deduced certain characteristics and metrics. <span style="white-space:normal;"><i></i></span><i>In fine<span style="white-space:normal;"></span></i>, the ultimate objective of our work is to design a document workflow management system, integrating a component of global behavior prediction. 展开更多
关键词 Document Processing WORKFLOW Hierarchic Chart Counting Processes Stochastic Models Waiting Lines Markov Processes Priority Queues Multiple Class and Subclass Queues
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Physical Quanta in Quasicrystal Diffraction 被引量:1
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作者 Antony J. Bourdillon 《Journal of Modern Physics》 2021年第12期1618-1632,共15页
Diffraction in quasicrystals is in irrational and geometric series with icosahedral point group symmetry. None of these features are allowed in Bragg diffraction, so a special theory is required. By means of a hierarc... Diffraction in quasicrystals is in irrational and geometric series with icosahedral point group symmetry. None of these features are allowed in Bragg diffraction, so a special theory is required. By means of a hierarchic model, the present work displays exact agreement between an <em>analytic</em> metric, with a <em>numeric </em>description of diffraction in quasicrystals—one that is founded on quasi-structure-factors that are completely indexed in 3-dimensions. At the quasi-Bragg condition, the steady state wave function of incident radiation is used to show how resonant response, in metrical space and time, enables coherent interaction between the periodic wave packet and hierarchic quasicrystal. The quasi-Bloch wave is invariant about all translations<em> <img src="Edit_ce7a6cbd-644e-4811-8416-a6f0c39eb4c3.png" alt="" /></em>, where <img src="Edit_f1f99a28-ba65-4079-aacc-c1b485bc7b16.png" alt="" /> is the quasi-lattice parameter. This is numerically derived, analyzed, measured, verified and complete. The hierarchic model is mapped in reverse density contrast, and matches the pattern and dimensions of phase-contrast, optimum-defocus images. Four tiers in the hierarchy of icosahedra are confirmed, along with randomization of higher order patterns when the specimen foil is oriented only degrees off the horizontal. This explains why images have been falsely described as having “no translational symmetry”. 展开更多
关键词 QUASICRYSTAL ICOSAHEDRA Hierarchic Resonant Response HARMONIC IRRATIONAL Geometric Series METRIC Diffraction Quanta
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Harmony Is Cause—Not Consequence—Of the Quantum 被引量:1
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作者 Antony J. Bourdillon 《Journal of Modern Physics》 2022年第6期918-931,共14页
Einstein claimed Bohr’s theory is incomplete: “the wave function does not provide a complete description of the physical reality” [1]. Their views represent two physics in schism [2] [3]. Quanta are fundamental. Th... Einstein claimed Bohr’s theory is incomplete: “the wave function does not provide a complete description of the physical reality” [1]. Their views represent two physics in schism [2] [3]. Quanta are fundamental. The theory of diffraction in quasicrystals, that is summarized here, is falsifiable and verified. The quanta are not only harmonic;but harmonic in dual series: geometric and linear. Many have believed the quantum is real;rather than conceptual and axiomatic. The quasicrystal proves its reality. 展开更多
关键词 QUASICRYSTAL ICOSAHEDRA Hierarchic Periodic Harmonic IRRATIONAL Geometric Series Metric Resonant Response Dispersion Dynamics
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A Two-Level Hierarchical Markov Decision Model with Considering Interaction between Levels
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作者 LIU Dan ZENG Wei ZHOU Hongtao 《Wuhan University Journal of Natural Sciences》 CAS 2013年第1期37-41,共5页
Decision in reality often have the characteristic of hierarchy because of the hierarchy of an organization's structure. In this paper, we propose a two-level hierarchic Markov decision model that considers the intera... Decision in reality often have the characteristic of hierarchy because of the hierarchy of an organization's structure. In this paper, we propose a two-level hierarchic Markov decision model that considers the interactions of agents in different levels and different time scales of levels. A backward induction algo- rithm is given for the model to solve the optimal policy of finite stage hierarchic decision problem. The proposed model and its algorithm are illustrated with an example about two-level hierar- chical decision problem of infrastructure maintenance. The opti- mal policy of the example is solved and the impacts of interactions between levels on decision making are analyzed. 展开更多
关键词 two-level hierarchic Markov decision processes multi-time scale backward induction
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APPLICATION OF NEURAL NETWORK WITH MULTI-HIERARCHIC STRUCTURE TO EVALUATE SUSTAINABLE DEVELOPMENT OF THE COAL MINES
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作者 李新春 陶学禹 《Journal of Coal Science & Engineering(China)》 2000年第2期92-96,共5页
The neural network with multi hierarchic structure is provided in this paper to evaluate sustainable development of the coal mines based on analyzing its effect factors. The whole evaluating system is composed of 5 ne... The neural network with multi hierarchic structure is provided in this paper to evaluate sustainable development of the coal mines based on analyzing its effect factors. The whole evaluating system is composed of 5 neural networks.The feasibility of this method has been proved by case study. This study will provide a scientfic and theoretic foundation for evaluating the sustainable development of coal mines. 展开更多
关键词 neural network multi hierarchic structure sustainable development coal mines
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Wave Harmonization in Hierarchic Quasicrystals by the Analytic Metric
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作者 Antony J. Bourdillon 《Journal of Modern Physics》 2019年第11期1364-1373,共10页
Thirty seven years after the discovery of quasicrystals, their diffraction is completely described by harmonization between the sine wave probe with hierarchic translational symmetry in a structure that is often calle... Thirty seven years after the discovery of quasicrystals, their diffraction is completely described by harmonization between the sine wave probe with hierarchic translational symmetry in a structure that is often called quasiperiodic. The diffraction occurs in geometric series that is a special case of the Fibonacci sequence. Its members are irrational. When substitution is made for the golden section τ by the semi-integral value 1.5, a coherent set of rational numbers maps the sequence. Then the square of corresponding ratios is a metric that harmonizes the sine wave probe with the hierarchic structure, and the quasi-Bragg angle adjusts accordingly. From this fact follows a consistent description of structure, diffraction and measurement. 展开更多
关键词 QUASICRYSTAL ICOSAHEDRA Hierarchic HARMONIZATION METRIC Geometric Series
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Accounting Hierarchical Heterogeneity of Rock Massif for Prediction of Mine Seismicity
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作者 Olga Hachay Andrey Khachay Oleg Khachay 《Open Journal of Geology》 2018年第3期187-200,共14页
Purpose: When producing mining operations in high-stress rock massive, technogenic seismicity is manifested. Forecasting and prevention of these events is given much attention in all countries with a developed mining ... Purpose: When producing mining operations in high-stress rock massive, technogenic seismicity is manifested. Forecasting and prevention of these events is given much attention in all countries with a developed mining industry. From the point of view of the paradigm of physical mesomechanics, which includes a synergetic approach to changing the state of rock massive of different material composition, this problem can be solved with the help of monitoring methods tuned to the study of hierarchical structural media. Changes in the environment, leading to short-term precursors of dynamic phenomena, are explained within the framework of hierarchical heterogeneity and nonlinearity from observations of wave fields and seismic catalog. For that purpose it is needed to develop new algorithms of modeling wave field propagation through the local objects with hierarchical structure. Design/Methodology/Approach: It had been constructed an algorithm for 3D modeling electromagnetic field for arbitrary type of source of excitation in N-layered medium with a hierarchic conductive and magnetic intrusion, located in the layer number J. It had been constructed algorithms for 2D modeling of sound diffraction and linear polarized transversal seismic wave on an anomaly elastic or dense intrusion of hierarchic structure, located in the layer number J of N-layered elastic medium. We used the method of integral and integral-differential equations for a space frequency presentation of wave field distribution. Findings: From the theory it is obvious that for such complicated medium each wave field contains its own information about the inner structure of the hierarchical inclusion. Therefore it is needed to interpret the monitoring data for each wave field apart, and not mixes the data base. Practical Value/Implications: These results will be the base for constructing new systems of monitoring observations of dynamical geological systems. Especially it is needed to prevent rock shocks in deep mines by their exploitation or natural hazards. 展开更多
关键词 Hierarchic Medium Electromagnetic FIELD Seismic FIELD Algorithms of Modeling New Monitoring Systems
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Interrelation of Chemical Elements Content in Plants underConditions of Primary Soil Formation
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作者 Vladimir Mukhomorov Liudmila Anikina 《Open Journal of Soil Science》 2011年第1期1-7,共7页
It is presented the results of a long-term and intensive experiment, which models the processes of primary soil formation under controlled agro-ecosystems. The influence of mineral substrate transformation is analyzed... It is presented the results of a long-term and intensive experiment, which models the processes of primary soil formation under controlled agro-ecosystems. The influence of mineral substrate transformation is analyzed on the content of chemical elements in plants tomato, and wheat. For the first time have been established dynamic synergistic and antagonistic interrelations between the chemical elements in a various bodies of the plant (roots, reproductive bodies, stems, and leaves). Using methods of the theory of information was revealed dynamics of collective state of chemical elements in the plants. It is shown that the collective states of the chemical elements which defined by the information function is strictly differentiated for different plant bodies, and have hierarchic order. We analyzed the following chemical elements Si, Al, Fe, Mg, Ca, K, P, S, Cl, Na, Mn, Zn. 展开更多
关键词 Chemical ELEMENTS Dynamics Synergism ANTAGONISM Information Function Hierarchic Order Soil Formation MINERAL SUBSTRATUM
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Analysis of the Metric in Quasicrystals—Linear Response in Logarithmically Periodic Solids
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作者 Antony J. Bourdillon 《Journal of Modern Physics》 2014年第12期1079-1084,共6页
The metric, that enables measurement of structural data from diffraction in quasicrystals, is analyzed. A modified compromise spacing effect is the consequence of scattering of periodic electromagnetic or electron wav... The metric, that enables measurement of structural data from diffraction in quasicrystals, is analyzed. A modified compromise spacing effect is the consequence of scattering of periodic electromagnetic or electron waves by atoms arranged on a geometric grid in an ideal hierarchic structure. This structure is infinitely extensive, uniquely aligned and uniquely icosahedral. The approximate analytic factor that converts the geometric terms base τ, into periodic terms modulo 2π, is . It matches the simulated metric cs=0.947, consistently used in second (Bragg) order, over a wide scale from atomic dimensions to sixth order superclusters. 展开更多
关键词 QUASICRYSTALS METRIC lin-log Response Measurement Logarithmic PERIODIC Hierarchic Structure
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Complete Solution for Quasicrystals
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作者 Antony J. Bourdillon 《Journal of Modern Physics》 2020年第4期581-592,共12页
A set of discoveries are described that complete the structural model and diffraction theory for quasicrystals. The irrational diffraction indices critically oppose Bragg diffraction. We analyze them as partly rationa... A set of discoveries are described that complete the structural model and diffraction theory for quasicrystals. The irrational diffraction indices critically oppose Bragg diffraction. We analyze them as partly rational;while the irrational part determines the metric that is necessary for measurement. The measurement is verified by consistency with the measured lattice parameter, now corrected with the metric and index. There is translational symmetry and it is hierarchic, as is demonstrated by phase-contrast, optimum-defocus imaging. In Bragg’s law, orders are integral, periodic and harmonic;we demonstrate harmonic quasi-Bloch waves despite the diffraction in irrational, geometric series. The harmonicity is both local and long range. A breakthrough in understanding came from a modified structure factor that features independence from scattering angle. Diffraction is found to occur at a given “quasi-Bragg condition” that depends on the special metric. This is now analyzed and measured and verified: the metric function is derived from the irrational part of the index in three dimensions. The inverse of the function is exactly equal to the metric that was first discovered independently by means of “quasi-structure factors”. These are consistent with all structural measurements, including diffraction by the quasicrystal, and with the measured lattice parameter. 展开更多
关键词 QUASICRYSTAL ICOSAHEDRA Hierarchic INTEGRAL Periodic Harmonic IRRATIONAL GEOMETRIC Series Metric
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Quasicrystals’ Resonant Response with Translational Symmetry
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作者 Antony J. Bourdillon 《Journal of Modern Physics》 2021年第7期1012-1026,共15页
Diffraction in quasicrystals is in logarithmic order and icosahedral point group symmetry. Neither of these features are allowed in Bragg diffraction, so a special theory is required. The present work displays exact a... Diffraction in quasicrystals is in logarithmic order and icosahedral point group symmetry. Neither of these features are allowed in Bragg diffraction, so a special theory is required. The present work displays exact agreement between the analytic metric with a numeric description of diffraction in quasicrystals that is based on quasi-structure factors. So far, we treated the hierarchic structure as ideal;now, we detail the theory by including two significant features: firstly, the steady state wave function of the incident radiation demonstrates how harmonics, in metrical space and time, enable coherent interaction between the periodic wave packet and hierarchic quasicrystal;secondly, mapping of the hierarchic structure for any influence of defects will allow estimation of possible error margins in the analysis. The hierarchic structure has the required logarithmic periodicity: superclusters, containing about 10<sup>3</sup> atoms, convincingly map phase contrast images;while higher orders leave space for subsidiary speculation. The diffraction is completely explained for the first time. 展开更多
关键词 QUASICRYSTAL ICOSAHEDRA Hierarchic INTEGRAL Periodic Resonant Response HARMONIC IRRATIONAL Geometric Series Metric
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Real Quanta and Continuous Reduction
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作者 Antony J. Bourdillon 《Journal of Modern Physics》 CAS 2022年第11期1369-1381,共13页
Previous theories of quasicrystal diffraction have called it “Bragg diffraction in Fibonacci sequence and 6 dimensions”. This is a misnomer, because quasicrystal diffraction is not in integral linear order n where n... Previous theories of quasicrystal diffraction have called it “Bragg diffraction in Fibonacci sequence and 6 dimensions”. This is a misnomer, because quasicrystal diffraction is not in integral linear order n where n&lambda;= 2dsin(&theta;) as in all crystal diffraction;but in irrational, geometric series τ<sup>m</sup>, that are now properly indexed, simulated and verified in 3 dimensions. The diffraction is due not to mathematical axiom, but to the physical property of dual harmony of the probe, scattering on the hierarchic structure in the scattering solid. By applying this property to the postulates of quantum theory, it emerges that the 3rd postulate (continuous and definite) contradicts the 4<sup>th</sup> (instantaneous and indefinite). The latter also contradicts Heisenberg’s “limit”. In fact, the implied postulates of probability amplitude describe hidden variables that are universally recognized, in all sensitive measurement, by records of error bars. The hidden variables include momentum quanta, in quasicrystal diffraction, that are continuous and definite. A revision of the 4<sup>th</sup> postulate is proposed. 展开更多
关键词 QUASICRYSTAL ICOSAHEDRA Hierarchic PERIODIC HARMONIC IRRATIONAL Geometric Series Metric Resonant Response Dispersion Dynamics
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Diffraction Line Width in Quasicrystals—Sharper than Crystals
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作者 Antony J. Bourdillon 《Journal of Modern Physics》 2016年第12期1558-1567,共11页
A quasicrystal has a structure intermediate between crystals and compound glasses. The disorder in glass makes its diffraction diffuse, so it is surprising that quasicrystals diffract more sharply than crystals. The g... A quasicrystal has a structure intermediate between crystals and compound glasses. The disorder in glass makes its diffraction diffuse, so it is surprising that quasicrystals diffract more sharply than crystals. The greater sharpness is computed to be due to the hierarchic structure with unit cell alignment in 3-dimensional space. Electron microscope phase contrast images map the comparatively heavy Mn atoms in icosahedral Al<sub>6</sub>Mn, where the transition metal locates the centers of unit cells inside clusters and superclusters. Because the solid is aperiodic, each diffracted beam is a product of multiple interplanar spacings combined, and this contrasts with the unique relationship between spacing and incident angle in Bragg diffraction from crystals. Simulated quasi-structure factors add the relative phase shifts that are in geometric series from cell to cluster to superclusters of increasing order. The scattering becomes coherent in best fit, angular configuration between the aperiodic solid and a longitudinally periodic X-ray or electron probe. The quasi-structure factors express angular divergence in each diffracted beam from its corresponding Bragg condition, and the divergence provides a special metric, essential for atomic measurement in the geometric solids. The fit is reinforced at all levels from the unit cell to cluster to high order superclusters. The optics operates under a new quasi-Bragg law in a new geometric space. In this paper, we proceed to examine the effect of specimen size on line resolution in diffraction, first analytically and secondly in simulation. The line resolution follows a power law on the supercluster order, matching its atomic population. 展开更多
关键词 QUASICRYSTAL Line Width Quasi-Structure Factor Geometric Space Hierarchic Metric
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Hierarchic Computations in Geometric Space—Showing Sharp Diffraction in Quasicrystals
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作者 Antony J. Bourdillon 《Journal of Modern Physics》 2016年第1期43-50,共8页
A quasi-structure factor method is used to show how sharp diffraction patterns are produced by aperiodic quasicrystals. Icosahedral symmetry is described for the tensor rank 3 solids with edge-sharing unit cells that ... A quasi-structure factor method is used to show how sharp diffraction patterns are produced by aperiodic quasicrystals. Icosahedral symmetry is described for the tensor rank 3 solids with edge-sharing unit cells that are pentagonally close packed in hierarchic structures having a geometric reciprocal lattice. The hierarchic symmetry replaces translational symmetry in crystal diffraction. Details in the calculation show how the symmetry is simulated in diffraction. 展开更多
关键词 QUASICRYSTALS Geometric Space Structure Factors Scattering Factors Hierarchic
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Mathematical Modeling Algorithms for Creating New Materials with Desired Properties Using Nano-Hierarchical Structures
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作者 Olga Hachay Andrey Khachay Oleg Khachay 《Advances in Materials Physics and Chemistry》 2019年第11期211-217,共7页
In the enormous and still poorly mastered gap between the macro level, where well developed continuum theories of continuous media and engineering methods of calculation and design operate, and atomic, subordinate to ... In the enormous and still poorly mastered gap between the macro level, where well developed continuum theories of continuous media and engineering methods of calculation and design operate, and atomic, subordinate to the laws of quantum mechanics, there is an extensive meso-hierarchical level of the structure of matter. At this level unprecedented previously products and technologies can be artificially created. Nano technology is a qualitatively new strategy in technology: it creates objects in exactly the opposite way—large objects are created from small ones [1]. We have developed a new method for modeling acoustic monitoring of a layered-block elastic medium with several inclusions of various physical and mechanical hierarchical structures [2]. An iterative process is developed for solving the direct problem for the case of three hierarchical inclusions of l, m, s-th ranks based on the use of 2D integro-differential equations. The degree of hierarchy of inclusions is determined by the values of their ranks, which may be different, while the first rank is associated with the atomic structure, the following ranks are associated with increasing geometric sizes, which contain inclusions of lower ranks and sizes. Hierarchical inclusions are located in different layers one above the other: the upper one is abnormally plastic, the second is abnormally elastic and the third is abnormally dense. The degree of filling with inclusions of each rank for all three hierarchical inclusions is different. Modeling is carried out from smaller sizes to large inclusions;as a result, it becomes possible to determine the necessary parameters of the formed material from acoustic monitoring data. 展开更多
关键词 Nano Hierarchic Objects Algorithms of Modeling Integral-Differential Equations Iterative Process Block Layered Medium Combined Hiererachical
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A Reexamination of Methods of Hierarchic Composition in the AHP 被引量:7
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作者 ZHANG Zhi-yong Economics and Management Department, Xi′an Petroleum University, Xi′an 710065, Shaanxi Province, China 《Systems Science and Systems Engineering》 CSCD 2002年第4期503-510,共8页
This paper demonstrates that we should use two different hierarchic composition methods for the two different types of levels in the AHP. The first method is using the weighted geometric mean to synthesize the judgmen... This paper demonstrates that we should use two different hierarchic composition methods for the two different types of levels in the AHP. The first method is using the weighted geometric mean to synthesize the judgments of alternative-type-level elements, which is the only hierarchic composition method for the alternative-type level in an AHP hierarchy, and the rank is preserved automatically. The second one is using the weighted arithmetic mean to synthesize the priorities of the criteria-type-level elements, which is the only hierarchic composition method for all the criteria-type levels, and rank reversals are allowed. 展开更多
关键词 analytic hierarchy process multicriteria analysis decision theory hierarchic composition priority synthesis rank preservation and reversal of the soil thermodynamic parameters such as the soil thermal conductivity soil heat capacity so
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