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The sideband amplification injection locking (SAIL) effect in the integrated mutual injection laser has been researched. Based on the SAIL effect in the integrated laser, the microwave photonics filter (MPF), the optoelectronic oscillator (OEO) and sideband modulation (SSB) in ROF link are proposed and experimentally realized. The SAIL effect expands the application of integrated optical injection laser in microwave photonics.

A new method for optical multiple-image encryption based on polarization-resolved diffraction imaging is proposed in this study. A linearly polarized beam is split into two beams of orthogonal polarization to illuminate different images to be encrypted, and these images are then encrypted into a single white-noise-like intensity image in a single shot. A multi-mode iterative phase-retrieval algorithm is used in the decryption to reconstruct the amplitudes and phases of the secret images simultaneously. Both computer simulations and optical experiments are performed to demonstrate the feasibility and effectiveness of the proposed method.

This paper introduces the design and implement of DDS based on FPGA. During the design process, the addressing way of ROM is proposed to improve the output frequency resolution. The optimization method called the compression method of ROM is advanced. The optimized design of NCO with different structures of accumulators (32 bits) including serial, parallel and pipelined is discussed. It is found that the pipeline (4 levels) accumulator has the biggest Fmax but consumes most LEs. There should be a balance between speed and resources during the design process. At last, DDS is implemented on ALTERA chip EP4CE15F17C8.

The feature vector mapping of process plant’s topology structure is one of the key problem in process plant topology similarity calculation. High quality feature vector does not only need to convert the expression from graph to length fixed vector, but also should mine and express the topology semantics that under the connective relationships. A novel method has been presented in this paper to solve this problem. We convert the topology graph to observation sequences according to the reacting processes with path extracting algorithm; then reference the state sequences from observation sequences with HMM, this can remove the node dependencies and mine the latent topology semantics; at last, reduce the state sequences to a length fixed vector with LDA model. The background and basis definitions has been introduced in this paper firstly, some related work has been also described; then we analyzed the characteristics of process plants’ topology structure and present the details of the mapping method; finally, the results have been evaluated. According to the manually judgement by process industry professionals, the method is proved to be practical and effective.

As more and more distributed generations existing in the grid, the directional overcurrent protection is required in the modern distribution network. The traditional method needs the voltage phasor as the reference that adds the cost. The current-only directional overcurrent protection can solve this problem to a certain extent. But, it can't recognize the fault direction when the direction of power flow is not fixed in the normal situation. This paper proposes a novel method that utilizes the information of the current flowing in the cable shield to overcome the drawbacks of previous current-only directional overcurrent protection.

Coke oven pushing optimization scheduling plays a important role in coke oven productions, especially in the abnormal operating conditions where sequences disorder problem often happens. In order to solve the sequences disorder problem, Firstly, we establish a coke oven pushing optimization scheduling model by means of the target of achieving the least punishment caused by distance, time and pushing coefficient in restoring normal order process. Secondly, in order to avoid the stagnation of the search in ant colony algorithm, adaptive ant colony optimization algorithm wais used to solve optimization scheduling model. Finally, through the simulation of actual production data, experimental results verified the effectiveness of the algorithm. It has a wide application prospect.

Aiming at the international engineering contractors' legal risk problem, based on the analysis of a large number of cases and literature review, we count the factors effecting legal risk from the contractor's perspective. And then we transform the existing legal risk management process by using the method of IDEF0 system. From the process planning, process design, process evaluation, process implementation angles, the system is modularized. Finally, we take a large Chinese international engineering contracting enterprise as an example and build the targeted supporting management mechanism.

Based on granular space, the hierarchical structure invariance and optimal approximation for proximity data are presented, and four results are obtained as follows. Firstly, an improved algorithm for computing the hierarchical structure and the related min-transitive closure of a fuzzy proximity relation are given, and the properties of key point sequence are studied by introducing the key points and key values of a fuzzy proximity relation. Secondly, two basic concepts, the hierarchical structure invariance and isomorphism of fuzzy proximity relations are introduced, and some examples are given to illustrate that the hierarchical structure of a fuzzy proximity relation is variant under three typical triangular norms. Thirdly, the hierarchical structure invariance theorem of fuzzy proximity relation under a mapping or transformation is given. Finally, for a given fuzzy proximity relation, a mathematical model for obtaining the optimal approximation in order to keep its hierarchical structure is established through the use of the linear combination of its minimum fuzzy proximity relation and min-transitive closure. These results help us understand the hierarchical structures, and provide theories and methodologies for the structural analysis and applications of proximity data.

The tecnnology of the coke oven heating up is complicated and difficult. The process of coke oven heating up is complicated and has many temperature measurement points, which supervision and control of the process is difficult. There were many factors which effect the change of the temperature .According to the change of temperature in the process, the supervision and control system of coke oven heating up was designed based on fuzzy control. The automatic supervision and control and data management were realized in the system. The system improved the production efficiency, and effectively ensured the process operations. The system has extremely practical value..

Generally, Performance Assessment (PA) of Construction Subject (CS) is based on “Post-Evaluation”. For one-time construction process, PA has limited ability to evaluate the process objectively. The Basic Model of the evaluation upon Process Performance (PP) in Construction Project (CP) was setup in this paper by AHP based on the Fuzzy Evaluation Method, and also by the study of comparison between the Process Performance (PP) concept definition in the construction project and its evaluation, In the mean time, the Model provides the specific guide-lines for evaluation during Construction Project (CP) Performance Assessment (PA) management process.

In order to evaluate a Quick Response Designing and Manufacturing System(QRDMS) roundly and objectively, a hierarchical and comprehensive evaluation index system for QRDMS is constructed, a multi-level fuzzy comprehensive evaluation approach based on analytic hierarchy process (AHP) is proposed in this paper. Then, an example is used to illustrate the proposed approach, and results indicate that the proposed approach is able to evaluation performances of QRDMS effectively and reasonably.

Instantaneous chip thickness during three typical end milling processes is analyzed in this paper. The tooth trajectory of a milling cutter is a combination of two motions, one is the rotation of the cutter spindle and the other is the feed motion of the cutter relative to work-piece. For simplification traditional chip thickness models always simplify the tooth trajectory as a circle to get approximate results. In this paper, modeling of true tooth trajectory in linear, arc and profile end milling processes is studied. And mathematical expresses for entry and exit angles of tooth, feed per tooth along cutter contact path are derived for undeformed chip thickness modeling. The instantaneous chip thickness of each process based on circular tooth trajectory model is analyzed as well for comparison. Cutting forces under different chip thickness models are also predicted to study the effect of tooth trajectory on milling process simulation.

the selection of reasonable machining parameters in numerical control milling process is the key issue to improve quality and productivity of product as well as save cost. In order to determine the optimal machining parameters instead of conservative ones used at present, a method of machining parameters management based on process planning knowledge was introduced in this paper. On the basis of analysis of process planning knowledge in milling process, an application mode was established, in which the storage, optimization, analysis and usage of machining parameters were considered. Finally, an application case was introduced to the optimization-usage program to validate the proposed system. The result shows that the application mode of machining parameters based process planning knowledge which were applied in NC milling process can shorten parameters selection time and increase productivity.

According to the randomness and self-correlation of individual demand, it is discussed in the necessity and feasibility of the introduction of fuzzy Markov chain model with weights to predict the future individual demand. The specific steps are explained: set up the classification by the standard deviation of sales series, and weighted by the standardized self-coefficients, calculated the transition probability matrix and the state probability. Then, a concrete forecasting value was obtained by using the level characteristics value of fuzzy sets. An example is presented on the sales forecasting of fast moving consumer goods in instant customerization, and it showed that the fuzzy Markov chain model with weights (FMCW) is more suitable for individual demand forecasting, compared with the Moving Average, Simple Exponential Smoothing, Linear Regression, and GM (1,1).

The effect of land reclamation on the water exchange of Tianjin coastal area in Bohai Bay was studied using an integrated hydrodynamic-dispersion numerical model. Based on the marine function regionalization, the whole Tianjin coastal area was divided into eleven sub-areas. The water exchange between each sub-area was calculated according to the numerical results and a matrix was introduced to represent the water exchange amongst the sub-areas. In particular, the effect of land reclamation on the water exchange in the two primary zones for sewage discharging was evaluated. Results show that: 1) The water exchange of southern Tianjin coastal area becomes weaker while the middle part of it becomes stronger due to the land reclamation. 2) Land reclamation makes the transport path of outlet sewage shifted.

Linear guideways, which are primary elements of ultra precision meso-machine tools, need reviewed considerations. Conceptual design of a ball bearing linear stage with limited dimensions is proposed. Evaluation of the table motion errors is worked based on the criteria that the balls always remain in elastic contact. Influences of the waviness of tracks, initial interference and resultant external load upon the perturbation displacement are taken into consideration.

According to asynchronous motor's complex fault characteristics, and the combination of wavelet transform technique, an improved wavelet neural network for fault diagnosis of asynchronous motor is proposed in this paper. Taking Wavelet transform technique as wavelet neural network(WNN) the input vector of picking up asynchronous motor's the characteristic signal, and wavelet neural network algorithm is ptimized, The self-adaptive wavelet neural network algorithm about adjusting momentum vector alter-learning rate is proposed and given the momentum coefficient and alter-learning rate adjustment method. Through the actual testified results show that the method is effective and feasible, and has a better diagnostic accuracy, fast and generalized performances.

Hotspots could degrade the performance of peer-to-peer (P2P) systems and add vulnerability to the system. This paper researches into the hotspots in P2P network, and present a new method to avoid generating the hotspots in the network by controlling the logical topology structure of P2P network. We firstly introduce the controlling ideas about seeking for spare nodes of the hotspots and distributing them into super-cube structure. Then, we disclose and interpret the controlling model, and give out the controlling algorithm. Finally, we validate our controlling model via simulations and the simulation results demonstrate that our work is effective to control the hotspots in P2P network. Thus, this model can improve the network competence to defend against coordinated attacks, promote the network robustness, and ensure the network would develop continually and healthily.

The work deal with the stabilization control of double inverted pendulum system. Inverted pendulum system is a complicated, nonlinear, unstable system of high order. Fuzzy control research for stabilization a double inverted pendulum at an upright position successfully is proposed based on weight variable fuzzy inputs. The weight variable fuzzy inputs is gained by combining the fuzzy control theory with the optimal control theory. The fuzzy control rules of a double inverted pendulum are given. In order to consider cart, the lower pendulum, the upper pendulum error information, three different fuzzy controller were designed in this paper. Simulation results show that the controller, which the upper pendulum is considered as main control variable, has higher accuracy and quicker convergence speed and higher precision, and simulation result is promising. The control result can be expanded the control of multilevel inverted pendulum, and have a guiding meaning in the control of other unstable system.

In this paper, a kind of fuzzy neural network based on hybrid genetic algorithms is proposed. Hybrid genetic algorithm is presented to train the fuzzy neural network. The hybrid genetic algorithm improved normal genetic algorithm. The BP algorithm is added to genetic algorithm. In particularly, the global convergent characteristic of the genetic algorithm is used to find the possible universal optimum, and the great feature of the BP algorithm, that is, error descend in the direction of grads, is used to fast search about the optimum. Thus, the fast learning capability and an accurate approximation ability are obtained. The fuzzy neural network is used to the control problem of truck backer-upper. The simulation results show that it achieves better control effect.

One of the most common artifacts for echo planar imaging is the ghost artifact, typically overcome with the aid of a reference scan preceding the actual image acquisition. In this work, we describe an automated free-scan-reference method for reducing ghost artifact using image-based correction. The two dimensional Fourier transformation of an entire data of image matrix is used to reconstruct two new images, one is reconstructed only by even rows, the other is only by odd rows, with the remaining ones zero-filled. Phase shift between even echoes and odd echoes can be computed by using the two images. Unwrapped phase shift gained by Marquardt-Levenber unlinear fitting can be used to suppress the ghost effectively.