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A signal processing method of passive bistatic radar using non-cooperative pulse radar illuminators is proposed. The proposed method estimates unknown parameters of transmitting radar signal from direct-path signal, and uses estimated parameters for coherent processing a series of pulses and positioning the detected maritime moving targets correctly in a 2D radar map, and to calculate the azimuth, bistatic range and Doppler frequency of targets. The experiments use the shore-based maritime surveillance radar as a non-cooperative transmitter and ships coming in and out from the seaport as the targets, which show that the proposed method can be applied to maritime moving target detection successfully.

Vertical rope-type recovery system is a new accurate recovery method for small fixed-wing unmanned aerial vehicles (UAV). This paper models the recovery system and finishes the simulation of recovery process. The recovery stand model of the recovery system is built by analyzing the physical essence, and the aircraft model is based on dynamics and kinematics equations as well as the mechanical characteristics of arresting rope. Finally the simulation analysis of the recovery process is completed. On the basis of the modeling simulation, the system parameters’ effect on recovery performance such as maximum resistance force, maximum overload and maximum radius has been discussed by varying each key parameter. Eventually, the pattern of how initial conditions when hitting the rope as well as the arresting rope’s stiffness and damping coefficient influence recovery performance has been researched, and the result could provide theoretical reference for the design of UAV using vertical rope-type recovery and the system in the future.

Buoyancy-lifting aerial vehicle is a new development direction of the near space vehicle. This paper presents two conceptual schemes of unmanned buoyancy-lifting aerial vehicle with different configurations. The general parameter design method is studied, and the general parameter calculation model is established. The general parameters of airship and the buoyancy-lifting aerial vehicle are compared and studied. Taking buoyancy-lifting aerial vehicle with single fuselage and dual wings as the research object, sensitivity analysis of parameters has been done. The results show that compared with the airship, the weight of the buoyancylifting aerial vehicle with single fuselage and dual wings is reduced by 23.0%. Weight of the buoyancy-lifting aerial vehicle with dual fuselages and dual wings is increased by 55.3% compared with the aircraft with single fuselage. Lift- buoyancy coefficient and cruise speed have important influence on the general parameters of the aircraft. With the energy density of the battery increasing from 400Wh/kg to 600Wh/kg, weight of the aircraft is reduced by 58.5%. Compared with the airship, weight of the buoyancy-lifting aerial vehicle is more sensitive to the propeller efficiency.

The capacitated lot-sizing and scheduling problem with sequence-dependent setup time and carryover setup state is a challenge problem in the semiconductor assembly and test manufacturing. For the problem, a new mixed integer programming model is proposed, followed by exploring its relative efficiency in obtaining optimal solutions and linearly relaxed optimal solutions. On account of the sequence-dependent setup time and the carryover of setup states, a per-machine Danzig Wolfe decomposition is proposed. We then build a statistical estimation model to describe correlation between the optimal solutions and two lower bounds including the linear relaxation solutions, and the pricing sub-problem solutions of Danzig Wolfe decomposition, which gives insight on the optimal values about information regarding whether or not the setup variables in the optimal solution take the value of 1, and the information is further used in the branch and select procedure. Numerical experiments are conducted to test the performance of the algorithm.

Migration of legacy systems to SOA has caught lots of attention in both academic and industry. People have proposed many methods, such as wrapping, reengineering etc. However, various characteristics of legacy systems can make the migration complicated, and different enterprises can afford different level migration cost. In this paper, the existing methods and options for evolving legacy systems are compared, and their advantages and disadvantages are identified respectively. Different adaptive situations are listed to assist in making migration decision.

In this paper, differences of the particle size between the pine smoke powders and lampblack powders were studied. The results showed that the particle spectrum of the pine smoke powders was unimodal distribution, while it was bimodal for the tung lampblack powders. The average particle size, volume of lampblack powders were about 1/3 and 3% of the pine smoke powders, respectively. But the specific surface area of lampblack particles was 5 times more than the pine smoke particles, which revealed the fact that the lampblack powders were more exquisite than the pine smoke powders .

PTT (Precipitate-Temperature-Time) curve of X80 pipeline steel was obtained by strain relaxation method. The evolution of precipitate particle size during holding process was simulated combined with kinetic calculation, and observed using TEM in the samples of industrial produced X80 steel with different holding time. It is revealed that the shape of PPT curve is typical “C” type with the nose temperature of 900°C and incubation time of about 5s. Kinetic calculation results show that the average particle size increases obviously with the increment of holding time. Meantime, after holding for 90s at 950°C, observation of industrial produced X80 steel reveals that the proportion of precipitate particles larger than 60nm increases dramatically, which basically agreed with the calculation results. Dissolved Nb can effectively reduce grain boundary mobility and retard recrystallization by solute drag effect. Therefore, it is strongly recommended to shorten the holding time without increasing holding temperature in industrial production, so that to reduce precipitate of Nb at high temperature, and increase the strength and toughness of steel.

The building sector is one of the highest energy consuming sectors in the world as well as in China, it is urgent to seek an energy efficiency way of sustainable architecture development. From the perspective of tradition, this paper focus on strategies of energy efficiency design that contained in excellent vernacular dwellings. On the basis of analyzing an example of Kangbaiwan Mansion, it illustrates the advantage of environment ecosystem, and summarizes the physical and cultural characteristic of its buildings, especially the climate-adapting overall arrangement and sustainable strategies of natural ventilation and passive solar gain, which can be a fertile source of modern energy efficiency architecture design as well as a proper way of inheriting the outstanding traditional culture.