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The construction of DNA logic circuits is the basis of DNA computers. DNA origami has nanoscale spatial addressability, which provides an ideal framework for the construction of DNA logic circuits. Here, we propose a strategy for constructing DNA logic circuits based on a DNA origami substrate. First, hairpin DNA strands are anchored on a DNA origami substrate to form a DNA wire track. Then, we design three different output ends for different logic circuits (AND, OR and NAND). The operations of the logic circuits are completed on the DNA wire track through the proximal hairpin circuit cascade. Finally, the results of the logical operation are determined by fluorescence detection. We use this strategy to construct two-input AND, OR, and NAND gates on a DNA origami substrate, and then extend this strategy to the construction of large-scale logic circuits and functional combinational logic circuits.

In this work, we consider the optimal control problem of linear quadratic regulation for discrete time-variant systems with single input and multiple input delays. An innovative and simple method t...

In this case study, longitudinal cracking of the 37Mn5 continuous casting tube billets was investigated. The coarse columnar grains, ferrite nets, and ferritic WidmanStatten structures were observed by optically metallurgical microscope (OMM). The main crack was covered by a layer of oxidation products in dark black color, and the oxidation products were mainly composed of FeO and Fe3O4. The intergranular features were observed by OMM and field emission scanning electron microscope. By analyzing the experimental results, the failure cause of 37Mn5 tube billets was attributed to rapid cooling in the cooling bed after ejection. Higher superheat and higher withdrawal speed promoted the cracking of the continuous casting billets.

In this paper, without assuming balanced network topologies, we address the weighted average consensus problem for discrete-time single-integrator multi-agent systems with logarithmic quantized information communication. By incorporating generalized quadratic Lyapunov function with the discrete-time Bellman-Gronwall inequality, a new upper bound about the quantization precision parameter of the infinite-level logarithmic quantizer is derived to design quantized protocol, under which agents in strongly connected directed networks can attain weighted average consensus. The obtained new upper bound clearly characterizes the intimate relation between the quantization precision parameter and the directed network topology. The proposed quantized protocol is particularly applicable to digital networks where balanced message passing among agents is not available.

Bolt as a connecting device plays more and more important role in various types of industry equipment. According to the needs of the domestic industry and on the basis of the automatic screw tightening control system requirements, this paper describes the design of screw-Machine electrical control system based on IPC independently.The main work probes into the electrical control system’s hardware structure and software structure.

Multiple-valued logic is an extended form of Boolean logic. In daily life, people often encounter the problem about the multiple-valued logic. With further study on Boolean logic, multiple-valued logic has been paid more and more attention by researchers. This paper achieves the operation of AND gate in three-valued logic by using the DNA hairpin structure. The experiment makes the DNA hairpin structure as the basic structure, and the molecular beacon as the input signal, and at last judges the logical results according to the intensity of fluorescence and gel electrophoresis. This method has the advantages that it has high sensitivity, good feasibility, and it is easy to observe. In addition, this method reduces the hybrid competition to a certain extent, and it is a new attempt to the research on multiple-valued logic.

Under the condition of high temperature, steel basic mechanical property index such as strength, elastic modulus falls sharply. Once there is a fire, long-span reticulated shell has serious damage. This paper, taking Kiewitt reticulated spherical shell as an example, uses ISO - 834 standard temperature - time curve to simulate fire and analyze the distribution of temperature field calculation and mechanical. Analysis by using transient thermal analysis in ANSYS software. Through ANSYS software to analog fire resistant properties of reticulated shell under the action of local fire resistant properties, it is concluded that the fire in the different parts of the structure on the structural deformation and destruction of the structure form, to a certain extent, reflects the overall structure fire resistance of spatial reticulated shell.

The most of Long-span stadium roofs are complex surface, the load norms cannot put forward the design requirements clearly in frequently. Determine wind loads need to use other means for help, while the numerical wind tunnel is one of the commonly be used to research methods in recent years. This paper introduces about the numerical simulation method of a long-span stadium roof surface wind pressure distribution , and based on FLUENT platform, a gymnasium as an example, the shear stress transport k - ω model (referred to as the SST k - ω model) on the roof surface wind pressure distribution of numerical wind tunnel simulation, analysis stadium roof surface pressure distribution law based on different wind directions.

Open ended cantilevered roof is different from enclosed roof, because its change of wind pressure distribution is complex, and the wind directions have great influence on it. Up to now, for the characteristics of the structure are very complicated, there is no appropriate wind load model can be used in design, especially under typhoon, a specific wind field. So it is necessary to study the characteristics of wind load on open ended cantilevered roofs of typhoon. Using FLUENT and Computational Fluid Dynamics technology, based on the conventional, Tianpu’s and Shiyuan’s turbulence intensity of the typhoon scenario, a numerical simulation of wind flow around a large-span cantilevered roof was carried out. Analyzed different wind angles of the wind pressure distribution regularities on large-span cantilevered roof. The paper determined the distribution of the surface wind pressure coefficient for the cantilevered roofs, as well as the wind-sensitive parts of structures.

Plasmid DNA algorithm of the minimal vertex covering problem is proposed upon the basic idea and operation of plasmid DNA computing model. In the plasmid DNA algorithm, though an appropriate encoding and the basic biological operation, we finish the generation and separation of solution. On the basis of the molecular biology methods, the algorithm is feasible.

About thirty years ago, the concept of the complexity of the problem was proposed. The most important complex class is P and NP class. Fruitful results of this concept are the existence of the so-called complex class complete problem. If the other issues of this class once solved in polynomial time, then the problem must exist polynomial time algorithms. Therefore, the complete problem is most difficult to solve, but because of their presence, we can choose any of them improved algorithm for a problem, so this kind of problem to get a good solution. DNA computing is a novel method that solving a class of intractable computational problems, in which the computing speeds up exponentially with the problem size. Up to now, many accomplishments have been made to improve its performance and increase its reliability. Maximum Independent Set problem (MIS) is a well-known NP-complete problem. Maximum Clique and Minimum Vertex Covering problem is equivalent to Maximum Independent Set problem. In this paper, we explore solving Maximum Independent Set problem by transforming it into equivalent 0-1 programming problem, and utilizing the surface computing model of that. The proposed method demonstrates universal nature of NP-complete problem.

The influence of the wind coefficient distribution on coal reservoirs for coal gangue is very important to its wind-resistance design. Take a real coal reservoir in Ordos for example, the wind pressure is numerically simulated with the help of Fluent Software. Because of the coal gangue piples, the average wind coefficient absolute obviously reduced under most of the wind directions, but the local area on the surface and leeward side the average wind coefficient absolute will increase significantly under the certain wind directions. Anyhow, the coal gangue is important to the wind pressure distributions of the coal reservoir and can't ignore its effect in the actual engineering design and should be given more attention.

With the development of Web service theories and technologies, it has been an effective approach to satisfy users’ requirements by service composition. For independent global constraints Web services composition problem, the paper presents an optimization method of Web service composition with constraint using fuzzy Petri net(FPN), which can transforms solving the optimal service composition problem into locating the largest trust value of legal firing sequences in the FPN model. Then we use the cooperative algorithm including simulated annealing and genetic algorithm (SAGA) to find the optimal legal sequences. The experimental results show that the method can not only reduce the time cost, but also find more feasible solutions.

The nullity of a graph is defined as the multiplicity of the eigenvalue zero in the spectrum of the adjacency matrix of the graph. We investigate a class of graphs with pendant trees, and express the nullity of such graph in terms of that of its subgraphs. As an application of our results, we characterize unicyclic graphs with a given nullity.

Prestressing of lattice shell is realized by cable, and author put forward a new kind of layout: The prestressing has been brought to bear by hoop and radial element of single-layer lattice shell, which avoid cable's effect on architectural purpose. The element has been made to sleeve, and the magnitude of prestressing is dominated by bolt. Article shows an example of K6, K8 single-layer spherical lattice shell, and the prestressing have been exert on partial ribs and hoops. The prestressing has been calculated by element axial force under normal loading. Stability of shells have been studied, and show the deformation satisfy the criteria under normal loading; The ultimate capacity has been improved obviously, loads transfer is rational. The new layout of prestressing is a promising technique.

Sticker model is one of the main DNA computing models, whose features are that it does not require extension of DNA strands in the biological process, does not require biological enzyme action and also the DNA strands can be reused In this paper, we try to solve the general 0–1 programming problem by utilizing these features of the model and its four basic operations (merger, separation, setting and clear). The solution of DNA computing is put forward in [6] and [7], thus we use the method learning from [7]'s idea described in this article to go on solving.

Because of its low-cost low-volume and little power waste , The uncooled infrared detector has widely used in military and civil affairs. But the imaging quality of the uncooled infrared detector is degraded badly even the image is not identified when the ambient temperature of the uncooled infrared detector is above 60 or under 0.Aim at this problem, a method of the local temperature control of the detector was proposed to improve the imaging performance of the uncooled infrared detector when its ambient temperature had a large dynamic range. A heat insulation structure between the detector and the readout circuit and the temperature control circuit based on pettier effect are designed. The pettier is wrapped around the detector and the temperature sensor is set in the detector. When the ambient temperature of the detector is range from -40 to 20 or from 30 to 70 the control circuit work and It can keep the ambient temperature of the detector about 30±5 .When the temperature is range from 20 to 30the control circuit do not work. By this design the ambient temperature of the detector is controlled near 30,so the detector can operate in the optimal temperature point recommended by manufacturer and the image quality can be hold in well. Based on the Sofradir 320×240 microbolometer ,above-mentioned method is used and the test prototype is made. The interesting experiments are done and the experiment results indicate that the method is feasible, effective, and can obviously extend the ambient temperature dynamic range for the practiced application of the uncooled infrared detector. In this paper, firstly Relations between the performance of the uncooled infrared detector and the operating temperature were analyzed simply. Secondly the method of local temperature control and the principal on how to improve the performance are described in detail. Thirdly the test prototype is introduced. Lastly the experiment results are given and some conclusions are discussed. Keyword: uncooled infrared detector, pettier effect, microbolometer ,temperature control

After Adleman’s paper published in 1994, a few of scholars solved some noted NP-complete problems on DNA computing. And all these methods of DNA computing are based on conventional Watson-Crick hydrogen bond of double-helical DNA molecule. Here we show that triple-stranded DNA structure mediated by RecA protein can be used for solving working operation problem. During the computation,sequence-specific recognition of double-stranded DNA by homologous deoxyoligonucleotides was fulfilled in the presence of . Triple-stranded DNA were separated and the desirable double-stranded DNA strands were retained and extracted, after adsorbed by the magnetic particles coated with streptavidin. It is suggested that the methods used may decrease the errors in DNA computation and be adopted to solve several problems in graph and combinatorial optimization.

3-vertex-colourability problem is one of computationally hard problems in combination optimization. The paper presented an algorithm via the interaction of PNA molecules and DNA molecules. We initially synthesized DNA memory strands of single molecular variety, and then PNA stickers were gradually annealed to specified regions on DNA strands, followed by magnetic bead separation to separate those memory strands that were not solutions. The novelty of proposed method is that solution to the problem of interest was constructed during the course of computation instead of searched in pre-synthesized vast solution space.

DNA computing is a novel method of solving a class of intractable computational problem, in which the computing speeds up exponentially with problem size. Up to now, many accomplishments have been made to improve its performance and increase its reliability. The positive integer linear programming is an NP-complete problem, in the paper, we solved the positive integer linear programming problem with fluorescence labeling techniques based on surface chemistry by attempted to apply DNA computing to programming problem. Our method has some significant advantages such as simple encoding, low cost, and short operating time.

DNA computing is being applied to solve problems in combinatorial optimization, logic and Boolean circuits. Breakthrough solutions in combinatorial optimization are the most impressive area of success but, in order to solve combinatorial optimization problems, problems related to the reliability of biological operators, stable DNA expressions, processing speed, expandability and the universality of evaluation criteria must be solved. This study implements a DNA sequence generation system that minimizes errors using DNA coding based on evolutionary models and performs simulation using biological experiment operators. The usefulness of this system is evaluated by applying the Hamiltonian Path Problem (HPP) in the form of a genetic algorithm. The proposed system generates sequences with minimal errors, as compared to existing systems, and identifies optimal solutions for combinatorial optimization problems in significantly reduced processing times.

Biological chip technology and DNA computing are new research areas in biology science and information science separately. The essential characteristic of both is the massive parallel of obtaining and managing information. The integer linear programming problem is an important problem in opsearch and it is an NP-complete problem. But up to now, there does not exist any good algorithm yet. A new DNA computing model is provided to solve a integer linear programming problem based on Molecular Beacon chip. In the method, the integer linear programming problem is solved with molecular beacon by fluorescing upon hybridization to their complementary DNA targets. The method has some significant advantages such as simple encoding, excellent sensitivity, high selectivity, low cost, low error, short operating time, reusable surface and simple experimental steps. The result suggest s the potential of Molecular Beacon used as a DNA computer chip.

A novel double mode constant modulus algorithm (NDMCMA) is presented in this paper to compensate the defects of the least mean Kurtosis constant modulus algorithm (LMKCMA) and the sign algorithm (SA), to effectively utilize the underwater acoustic channel (UWAC) finite bandwidth, and to improve the underwater communication speed. The SA is applied to the LMKCMA and sign LMKCMA (SLMKCMA) is proposed. The SLMKCMA and the LMKCMA are fused to come into being the NDMCMA. Based on the decision of the equalizer's output, iteration process of the NDMCMA switches between the LMKCMA and the SLMKCMA automatically. The NDMCMA is more robust than the SLMKCMA, and more computationally efficient than the LMKCMA. Therefore, it is very suitable for the recovery of the underwater data transmission. The performance of the NDMCMA is proven by computer simulation for the equalization of the UWAC.

The computational complexity of fourth-order cumulants (FOC) estimation of quasi-stationary random process is high and it is very difficult to apply the FOC to solve the actual problem. For improving the practicability of the FOC, the FOC simplification calculation method is proposed based on its direct estimation formula and the relation between FOC recursive estimation and its computational complexity. The FOC simplification calculation based adaptive line enhancer (FOCSCBALE) is established. The FOCSCBALE has low computational load and ability to suppress Gaussian noise. Simulation tests with the real data of underwater target and theory analysis have proven the validity of the FOC simplification calculation method and the FOCSCBALE.

xperimenta1 simulation analysis of non-linear proble m----with regard to investigation into the mechanical and opticalbehaviour of silver chlorider of photoplastic materialZhixiang Yin Shikun 2hang Zongyan LiFuxin Mining Institute,Puxin Liao Ning,ChinaABSTRACTTo solve non-linear problem. by means of exprimental simulation,the polycrystalline photoplastic material-———Silver Chlorider(AGCL),has been systimaticlly investigated,including the determination ofthe mechanical and optical behaviour of AGCL.A number of experimentalresults has been presented in order to simulate experimentally non-—linear problems.Pinally,the problems in experimental technique arepointed