Covalent organic frameworks (COFs) are a class of crystalline porous polymers that allow the atomically precise integration of organic units to create predesigned skeletons and nano-pores. Since the seminal work of Yaghi on covalent organic frameworks, this subject has attracted extensive interest not only from chemists’ science and organic synthesis, but also from various researchers in the fields of gas storage, heterogeneous catalysis, semi-conduction and photoconduction. This review describes the building blocks of COFs and synthetic methods. The applications are also studied and evaluated. Concerning COFs for future research, some suggestions are proposed and conclusions are given.

How to acquire creative ideas of making new products and new items? This is a difficult problem for managers. The relationship of creative ideas and contradictory problems is introduced, and the mechanism for generating creative ideas and the methods of generating creative ideas for a new product from made products are explored. It is indicated that the theoretic foundation of generating creative ideas is extension theory and the methods of generating creative ideas are innovation methods. And then the progress of generating creative ideas making use of the basic thinking and method of Extenics for generating creative ideas using the advantage of computer's enormous storage and its high speed is introduced.

Complex contradiction often occurs in handling engineering contradictions. However, its definition and formalized description have not been studied, which make intelligent processing impossible. In order to solve the problem, complex contradiction and some key terms such as contradictory information unit and contradictory information unit set are defined and clarified. Also, the methods and steps expressing information units of complex contradiction are given. The results can provide theoretical basis for the analysis and solution of complex contradiction in intelligent processing on engineering contradiction.

Grey emergency command system that contains randomness, fuzziness, certainties, uncertainties and incompleteness. This paper, for the purpose of an optimal contingency plan, uses gray correlation analysis of the emergency response command system indexes for data analysis. It first defines the gray correlation analysis method to calculate the best assessment of each of emergency index vector sequence, then builds a system of gray correlation matrix to calculate the weight value of each index, and finally gets an effect level gray correlation and contingency plan through calculation to design an optimal contingency plan, which can play a decisionmaking role in planning a more objective and reasonable emergency command system.

This paper discusses the classification rules of chaos in 3-dimensional quadratic autonomous systems. The author develops a new effective classification and provides a basic classification framework. Based on regulatory network, the research first views a chaotic system as a regulatory network in which every node corresponds uniquely to a variable in the chaotic system. Then, it studies the relationship between regulatoy networks of 3 nodes and 3-dimensional autonomous chaotic system of polynomial type. Finally, the paper classifies 3-dimensional autonomous chaotic systems of polynomial type from the viewpiont of regulatory network.

How to allocate resources reasonably and effectively has been an important problem in the field of cloud computing. For traditional cloud resource allocation algorithms can not effectively shield the isomerization of underlying hardware resources, and they also can not neglect the categories of different layers' cloud service, this paper proposes a multi-parameter resource packing method, and constructs a cloud resource allocation control model based on discrete event system. Besides, it gives a reasonable resource allocation algorithm. By calculating the close degree of capacity parameters from each resource package over the servers and the resource demands of the clients, the algorithm defines the resource allocation events, and hierarchically controls the states’ occurrence or nonoccurrence. Finally, the entire resource allocation system will reach an acceptable state. The experiments show that the cloud resource allocation model based on the discrete event system can guarantee that under the acceptable state, not only each resource request can get a reasonable allocation, but also the resource can get a maximal utilization.

This article discusses the architecture design of DMA controller on high performance GPS receiver based on RTEMS which achieves the optimal integration of DMA IP and navigation baseband system. The authors designed the hardware architecture of DMA IP and made full use of hardware performance with the idea of multiplexing, then used register and FIFO buffer to achieve read-write control. Furthermore, the researchers designed the DMA controller with Verilog HDL and verified the design on Altera Cyclone4 FPGA. The result demonstrates that DMA controller can ease the CPU’s burden and shorten the acquisition & tracking time which improves the performance of the whole system.

Based on 3D CT image reconstruction system for analysis and other aspects of the jaw morphology, stability and aesthetic dental implanting depend on 3D position of the implanting in the jaw. Since that, this paper proposes a full-featured interactive positioning method and discusses three-dimensional model of the coordinate transformation and coordinate data extraction technology. Combined the function of extraction database in VTK with the characteristics of needle puncturing for points, it obtains three-dimensional image coordinates of mandible by interactive operations to achieve the implant positioning of three-dimensional jaw image. The researchers compare this with the coordinates of the intelligent positioning of the implant. And through minor adjustment, the latter reduces the errors such as in the direction of the implant and implanting length, which effectively improves the accuracy and security of the virtual dental implant navigation system.

A new algorithm aiming at improving the estimation accuracy of direction of arrival (DOA) based on uniform circular array (UCA) has been proposed in this paper. Compared with other algorithms, the new proposed one can make the most of the useful information hiding in the received signal by shifting virtually in two vertical direction. Firstly, it shifts the mathematical mode of array received signals at the z axis and x axis respectively with the method of mode excitation. And then, two new full rank Toeplitz matrices relating to the information of DOA estimation have been reconstructed so the purpose of decorrelation has been achieved. Through the different properties of rotation factor at z axis and x axis successively, the researchers obtain the estimation of pitch angle and then the estimation of azimuth angle. Result analysis of simulation shows the validity of the DOA estimation of coherent signal as well as the strong coherence and low SNR incoming signals.

As a typical representative of clustering algorithm, DBSCAN algorithm has the advantages of fast speed and helps to find the noise of data. However, in big data processing, there are problems of low clustering efficiency, high memory and I/O requirement, and poor clustering precision. With the support of cluster computer technology especially the development of cloud computing, the solutions to the problems of DBSCAN algorithm mentioned above can be provided and progressed significantly. This paper proposes a parallel PMDBSCAN algorithm based on data partition which can pre-process data partition before clustering, realize parallelization of DBSCAN algorithm by parallel programming model MapReduce, and reduce I/O consumption according to overlapping partition. The results show that in dealing with large-scale data the PMDBSCAN algorithm increases the speed of clustering, reduces I/O consumption and improves cluster quality significantly.

This paper proposes a gravitational search algorithm of adaptive chaos mutation. By introducing the average distance and the chaotic search variation, this paper improves local search ability of gravity algorithm, increases the diversity of substance population and treats the unfeasible materials after mutation by boundary variation constraint. The results show that the new algorithm has the advantages of high precision and fast rate in convergence which can effectively avoid premature convergence. And the variation of the material after not feasible material treated by boundary variationconstraint.

This paper takes the nonlinear delay differential equation as the research subject and uses the fixed point theorem to prove asymptotic stability of nonlinear differential equations with delays. Some sufficient conditions for asymptotic stability of the trivial solution are also established.

For the multi-objective optimization in real life，there are many preferences of decision makers. This paper proposes a new preference: the weight preference of objective function which derives and scores from its importance according to policy makers by Delphi method. This preference, expressive and facilitating, combines with M2M algorithm into a hybrid algorithm for solving multi-objective optimization problems. The experiments show that various preferences lead to different results in working out the multi-objective optimization problem, which coincides with the actual practice. Apart from its theoretical contribution, this preference also has its realistic significance.

This paper discusses the Lagrange convex functional and the duality property in non-reflexive Banach space. In the discussion, two concepts about generalized subdifferential have been introduced and their relationship has been studied. Also it is pointed out that the Lagrange convex functional has the B-self-dual property.

According to the huge market demand for the PWM dimming lamps of two-channel cold/warm LED lighting source and the existing problems in dimming technique, a lighting source system control algorithm based on time hybrid color mode is proposed in this paper and the independent modulation of hybrid lighting source luminance and color temperature are realized by this method. Experimental result shows that, in the process of color temperature adjustment, luminance keeps constant basically. And in the process of brightness adjustment, color temperature is also constant. This algorithm reduces the computing load of controller. At the same time, it improves the dimming control precision and eliminates the transient power overload phenomena for reliability of lighting system.

In this paper, the near infrared persistent luminescent material ZnGa₂O₄：Cr³⁺ is prepared by a high temperature solid state method and the photoluminescence, long persistent photoluminescence, photostimulated luminescence and thermoluminescence properties of ZnGa₂O₄：Cr³⁺ are studied in details. The persistent luminescence excitation spectra reveal that the persistent luminescence of ZnGa₂O₄：Cr³⁺ comes from the charge transfer transition from O^2-to Ga³⁺ instead of the intrinsic transition of Cr³⁺. The investigation in photo-stimulated persistent luminescence indicates that the sample can emit bright persistent luminescence again under infrared light excitation after the UV light excited persistent luminescence decays completely. The result shows that the UV light written information in ZnGa₂O₄：Cr³⁺can be read by infrared light. Moreover, in accordance with the result, the recombination luminescence model of conduction electrons is employed to elaborate the luminescence mechanism of the sample.

Combined with a project in Guangzhou, the whole model of two-dimensional finite element is established through the diaphragm wall, inner supporting and soil layer. The numerical simulation of deep foundation excavation under the construction process is carried through. Research shows that：With excavation depth increasing, the horizontal displacements of retaining structures increase and the location of the maximum values changes from the top to middle of the retaining structures. The horizontal displacement curves of the retaining structures have a “bow shape”. The monitoring results are compared with the measurement values. The supporting construction plays an important role on the decrease of the horizontal displacement of the pile. The maximum horizontal displacement is 24.6 mm without supporting constructions. And the elasticity modulus of soils has great impact on the foundation displacement. The result can provide valuable references for the design and construction of similar projects.