Practical pattern-based design recovery approach

A practical approach is presented to enlarge the recoverable scope and improve the precision of pattern recovery. To specify both structural aspects and behavioral aspects of design patterns, we introduce traditional predicate logic combined with Alien's interval-based temporal logic as our theoretical foundation. Moreover, we take the Visitor pattern as an example to illustrate how to specify design patterns to support recovery of design patterns besides structural category. The experimental results show that the approach presented is practical for recovering design information of real world systems.

Scheduling method for single-arm cluster tools of wafer fabrications with residency and continuous reentrancy

In order to enhance the utilization of single-ann cluster tools and optimize the scheduling problems of dynamic reaching wafers with residency time and continuous reentrancy constraints, a structural heuristic scheduling algorithm is presented. A nonlinear programming scheduling model is built on the basis of bounding the scheduling problem domain. A feasible path search scheduling method of single-arm robotic operations is put forward with the objective of minimal makespan. Finally, simulation experiments are designed to analyze the scheduling algorithms. Results indicate that the proposed algorithm is feasible and valid to solve the scheduling problems of multiple wafer types and single-ann clusters with the conflicts and deadlocks generated by residency time and continuous reentrancy constraints.

Motion simulation and experiment of a novel modular self-reconfigurable robot

Based on the character of the modular self-reconfigurable （MSR） robot, a novel homogeneous and lattice MSR robot, M-Cubes, was designed. Each module unit of the robot has 12 freedoms and is composed of six rotary joints and one cubic link. An attached/detached mechanism was designed on the rotary joints. A novel space transmitting system was placed on the inner portion of the cubic link. A motor separately transmitted torque to the six joints which were distributed equally on six surfaces of the cubic link. The example of a basic motion for the module was demonstrated. The result shows that the robot is concise and compact in structure, highly efficient in transmission, credible in connecting, and simple in controlling. At the same time, a simulator is developed to graphically design the system configuration, the reconfiguration process and the motion of cluster modules. The character of local action for the cellular automata （CA） is utilized. Each module is simplified as a cell. The transition rules of the CA are developed to combine with the genetic algorithm （GA） and applied to each module to accomplish distributed control. Simulation proves that the method is effective and feasible.

Design of a novel modular self-reconfigurable robot capable of self-turning

To solve the problem of inaccurate angle adjustment in the self-assembly process, a new homogenous hybrid modular self-reconfigurable robot-Xmobot is designed. Each module has four rotary joints and a self-turning mechanism. With the proposed self-turning mechanism, the angle adjusting accuracy of the module is increased to 2°, and the relative position adjusting efficiency of the module in the self-assembly process is also improved. The measured maximum moving distance of the proposed module in a gait cycle is 11.0 cm. Aiming at the multiple degree of freedom （MDOF） feature of the proposed module, a motion controller based on the central pattern generator （CPG） is proposed. The control of five joints of the module only requires two CPG oscillators. The CPG-based motion controller has three basic output modes, i. e. the oscillation, the rotation, and the fixed modes. The serpentine and the wheeled movements of the H-shaped robot are simulated, respectively. The results show that the average velocities of the two movements are 15. 2 and 20. 1 m/min, respectively. The proposed CPG-based motion controller is evaluated to be effective.

Improved design of reconfigurable frequency response masking filters based on second-order cone programming

In order to improve the design results for the reconfigurable frequency response masking FRM filters an improved design method based on second-order cone programming SOCP is proposed.Unlike traditional methods that separately design the proposed method takes all the desired designing modes into consideration when designing all the subfilters. First an initial solution is obtained by separately designing the subfilters and then the initial solution is updated by iteratively solving a SOCP problem. The proposed method is evaluated on a design example and simulation results demonstrate that jointly designing all the subfilters can obtain significantly lower minimax approximation errors compared to the conventional design method.

Deformation Analysis and Stability Evaluation of the Main Shaft at Jinchuan Mine No.3

Unexpected, serious deformation failures have occurred during construction of a main shaft. A study of construction parameters of the main shaft is required. First, the stability of the shaft and wall-rock is investigated by numerical methods. The modeling results are as follows： The convergence of shaft liner is greater than 60 mm at a depth of 650 m; the maximum principal stress in the liner approaches 190 MPa, which exceeds the strength of the liner, so it is inevitable that the liner deform locally. Second, stability analysis of shafts with different liner thicknesses has been completed. The results have the following features： If the depth where the liner thickness is increases from 400 mm to 500 mm is 650 meters, the convergence deformation of the liner is reduced by 3.4 mm while the maximum principal stress is reduced by 5 MPa. At a depth of 250 m if the liner thickness is increased from 400 mm to 500 mm the convergence of the liner is reduced by 1.5 mm while the maximum principal stress is reduced by 10 MPa. Therefore, increasing the liner thickness has little effect on liner convergence but can reduce the maximum principal stress in the liner. The thickness of the liner can be increased to reduce the maximum principal stress and increase the capacity for shear deformation. Finally, construction techniques employing releasing-displacements have been numerically simulated. The conclusions are that as the releasing displacement is increased the convergence of the surrounding rock increases linearly while the convergence of the lining decreases linearly. The plastic zone in the surrounding rock mass at first increases linearly but then, at a release-displacement of 95 ram, expands rapidly. These conclusions show that use of suitable releasing displacement can increase the self-supporting capacity of the surrounding rock. But when the releasing displacement exceeds 95 nun the plastic zone rapidly enlarges and stability rapidly decreases. The maximum principal stress of the lining also decreases as the release-displacement increases. There is a definite inflection point in the relationships involving releasing displacement. When the releasing displacement passes this point the effect on principal stress decreases. In conclusion, a reasonable releasing displacement value when lining the shaft is 95 mm.

Coordinated control strategy for robotic-assisted gait training with partial body weight support

Walking is the most basic and essential part of the activities of daily living. To enable the elderly and non-ambulatory gait-impaired patients, the repetitive practice of this task, a novel gait training robot(GTR) was designed followed the end-effector principle, and an active partial body weight support(PBWS) system was introduced to facilitate successful gait training. For successful establishment of a walking gait on the GTR with PBWS, the motion laws of the GTR were planned to enable the phase distribution relationships of the cycle step, and the center of gravity(COG) trajectory of the human body during gait training on the GTR was measured. A coordinated control strategy was proposed based on the impedance control principle. A robotic prototype was developed as a platform for evaluating the design concepts and control strategies. Preliminary gait training with a healthy subject was implemented by the robotic-assisted gait training system and the experimental results are encouraging.

The computer-aided design method of cabinet based on style imagery

Due to the practical problems of the high costs and the long development cycle of China’s cabinet production,a computer-aided design method of the cabinet based on style imagery is proposed.According to the principle of the conjoint analysis method, the rough set theory and the weight coefficient of different components of the cabinet,a multi-dimensional model of style imagery to evaluate the cabinet is built. Then the related constants of style imagery are calculated and the cabinet components library is also built by the three-dimensional modeling.Finally,with recombinant technology and the mapping model between cabinet style and external characteristics,the prototype system based on Visual Studio is proposed.This system actualizes the bidirectional reasoning between product style imagery and the shape features,which can assist designers to produce more creative designs,greatly improve the efficiency of cabinet development and increase the profits of companies.

A new method to estimate wave height of specified return period

In this paper, we propose a new method to estimate the wave height of a specifi c return period based on the Hurst rule and a self-affi ne fractal formula. A detailed description of our proposed model is presented in this paper. We use the proposed model to analyze wave height data recorded along the coast of Chaolian Island from 1963 to 1989. The results show that the performance of our proposed model in estimating design wave heights is superior to traditional models.

Design and implementation of a modular self-reconfigurable robot

A novel modular self-reconfigurable robot called UBot is presented.This robot consists of severalstandard modules.The module is cubic structure based on double rotational DOF,and has four connect-ing surfaces that can connect to adjacent modules.A hook-type mechanism is designed,which can quick-ly and reliably connect to or disconnect from adjacent module.This mechanism is self-locking after con-nected,and energy-saving.To achieve small overall size and mass,compact mechanical structures andelectrical systems are adopted in modular design.The modules have embedded power supply and adoptwireless communication,which can avoid cable-winding and improve flexibility of locomotion and self-re-configuration.A group of UBot modules can adapt their configuration and function to the changing envi-ronment without external help by changing their connections and positions .The basic motion and self-re-configuration are proposed,and the experiments of worm-like locomotion are implemented.

Application of Refactoring and Design Pattern in Land Information System Development

The unceasing change problem of land information systems can be resolved through the refactoring and design pattern. To promote the implementation of design pattern and refactoring methods in developing land information systems reusing software design, applying refactoring methods to the abstract factory and decorator design patterns in land information system development is discussed.

Gastric electrical stimulation for gastroparesis:A goal greatly pursued,but not yet attained

The lack of an effective medical treatment for gastroparesis has pushed the research of new techniques of gastric electrical stimulation (GES) for nearly half a century of experimentation with a large variety of electrical stimuli delivered to the gastric wall of animals and patients with gastroparesis. Three principal methods are currently available: gastric low-frequency/high-energy GES with long pulse stimulation, high-frequency/low-energy GES with short pulse stimulation and neural sequential GES. The first method aims to reset a regular slow wave rhythm, but has variable effects on contractions and requires devices with large and heavy batteries unsuitable for implantation. High-frequency/low-energy GES, although inadequate to restore a normal gastric electro-mechanical activity, improves dyspeptic symptoms, such as nausea and vomiting, giving patients a better quality of life together with a more satisfactory nutritional status and is suitable for implantation. Unfortunately, the numerous clinical studies using this type of GES, with the exception of two, were not controlled and there is a need for definitive verification of the effectiveness of this technique to justify the cost and the risks of this procedure. The last method, which is neural sequential GES, consists of a microprocessor-controlled sequential activation of a series of annular electrodes along the distal two thirds of the stomach and is able to induce propagated contractions causing forceful emptying of the gastric content. The latter method is the most promising, but has been used only in animals and needs to be tested in patients with gastroparesis before it is regarded as a solution for this disease.

Application of H~∞ control in rudder/flap vector robust control of a ship's course

Given the uncertainty of parameters and the random nature of disturbances that effect a ships course, a robust course controller should be designed on the basis of rudder/flap vector control. This paper analyzes system uncertainty, and the choice of weighting functions is also discussed. When sea waves operate on a ship, the energy-concentrating frequency varies with the angle of encounter. For different angles of encounter, different weighting functions are designed. For the pole of a nominal model existing in an imaginary axis, the bilinear-transform method is used. The "2-Riccati" equation is adopted to solve the H∞ controller. A system simulation is given, and the results show that, compared with a PID controller, this system has higher course precision and more robust performance. This research has significant engineering value.

Combustion characteristics of Methanol-base fuel （MBF） made by coal

Profound experimental research was made on Methanol-base fuel （MBF） mainly consisting of methanol, and the results were compared with that of diesel oil. Their respective combustion characteristics of caloric value, combustion efficiency and components of smoke were synthetically analyzed by employing the electronic weighing devices, the rotor flow-meter, intelligent flue gas analyzer, advanced bomb calorimeter, etc., referring to the feasibility of taking it as a fuel for general use. Experiment results show that Methanol-base fuel not only has superiorities on combustion characteristics but also bears energy saving and environmental protection advantages.

Inherently safer reactors and procedures to prevent reaction runaway

Reaction runaway has longtime been an issue in chemical industry as it often leads to severe accidents if not controlled and inhibited properly.Herein we have reviewed several key considerations and procedures to prevent such phenomena,including inherently safer reactor design,thermal risk assessment and early warning detection of runaway,and pointed out that the basic principle underlying is necessary heat management and construction of resilient processes.For inherently safer reactor design,important factors such as heat removal,heat capacitance,flow behaviors and explosive behaviors have been investigated.The survey shows that heat exchanger(HEX) reactor and microreactor outperform traditional reactors.Meanwhile,we have looked into the effect of thermal risk ranking and safety operation region determining for thermal risk assessment,and the influence of runaway criteria and construction methods for early detection of reaction runaway as well.It shows that thermal risk assessment plays a key role on process design,and early warning detection system(EWDS) is preferable on prevention of reaction runaway.In the end,perspectives regarding inherently safer designs with the measures discussed above have been provided.

Research on the special lifting devices for steel box girders of Sutong Bridge

Sutong Bridge is a cable-stayed bridge with a steel box girder and a main span of 1 088 m.The steel box girder of main span includes five portions:back span large unit,large block of pylon,standard girder,back span closure girder and middle span closure girder.Each back span large unit is fabricated by welding several deck segments together in factory,and is erected by floating crane.As navigational clearance of the main bridge is high,the traditional truss lifting device can't satisfy the requirement of domestic lifting cranes for this kind of lifting height and weight.Hence,a kind of lighter lifting device for the erection of back span large units was accepted for this bridge.In this paper,the design and use of this lifting device is introduced.The upper structure used lifting gantry to install the standard girder segment by cantilever method.Because the bridge's navigation clearance is high,and the girder segment is wide and heavy,the meteorology and hydrology condition of the bridge district is abominable,and the requirements of long cable girder side pull-in,structure and performance propose high request to the lifting gantry.In this paper,the design and use key point of long cable pull-in angle adjustment device integrate into lifting gantry is introduced.

Environmental hazard and ecological infrastructure construction of hilly city:a case of metropolitan area of Chongqing Municipality

This paper takes metropolitan area of Chongqing Municipality as an example, Chongqing, located at the tail area of the Three Gorges Reservoir; is a typically in-land hilly city in China. A series of serious eco-environmental hazard affecting hilly city, have appeared： the forest landscape has been fragmented; the stability of ecological system has nat been maintained： soil erosion has been serionus; geological disasters have become more and more frequented; the phenomenon of city ＂heat islands＂ is obvious： and environmental pollution is worsened with Iow physical self-puri- fication. All of the hazards above will affect ecological security of the tail area of the Three Gorges Reservoir and sustainable development of Changqing. In order to guarantee ecological security and health of Chongqing and the Three Gorges Reservoir, the eountermeasures for ecological infrastructure construction are put forward： quickly drawing up ecological infrastructure planning of Chongqing Municipality, strengthening the integration and continuation of hilly-water spatial pattern, maintaining the diversity and stability of local ecosystem, establishing the green space system in-cluding suburban.forest, farmland and green space. recovering wetland ecosystem, optimizing industrial structure and urban spatial distribution, developing recycling economy; establishing ecological infrastructure monitoring network and information forecast system, carrying out ecological management for Chongqing Municipality and so on.

Empirical Studies of Ecological Civilization Education in Vocational Colleges--Take Chongqing Vocational Institute of Engineering as the Example

Vocational college students are an important force in the country＇s future socialist construction, and their concept of ecological civilization will directly affect the future of socialist construction. This article conducted a questionnaire survey by among 960 vocational college students, and it found that the presence of ecological civilization vocational colleges of education-related departments at all levels of ecological education vocational college students are lack of rational cognition, and the attention is not enough. Therefore, educators should explore effective ways of ecological civilization education colleges, the competent authorities in the school attaches great importance to play the main channel of the effectiveness of teachers and classrooms, and strengthen ecological civilization education; improving vocational college students initiative and practicality, strengthen ecological and environmental legal education to enable students to form a sense of ecological civilization and habits, in order to receive a good education results.

A study on TCP performance of crowdsourced live streaming

The prevalence of smart phone and improvement of wireless net promote the usage of crowdsourced live streaming,where individual users act as live streaming sources to broadcast themselves online. Characterizing the performance and identifying its bottleneck in such systems can shed light on the system design and performance optimization. TCP performance of a commercial crowdsourced live streaming system is examined by analyzing packet-level traces collected at streaming servers. TCP stalls that heavily hurt the Qo E of user have been identified. In particular,the TCP stalls account for as much as 31. 6% of the flow completion time for upload flows and result in abandonment of upload on the corresponding channels. Stalls caused by timeout retransmissions are further dissected and timeout retransmission characteristics are revealed to be dependent on the video encoding methods. These findings provide new insights in crowdsourced live streaming systems and can guide designers to improve the TCP efficiency.

Mechanism Design and Motion Analysis of Heavy⁃Load Transfer Robot with Parallel Four⁃Bar Mechanism

Heavy-load transfer robots are widely used in automobile production and machinery manufacturing to improve production efficiency.In order to meet the needs of large billet transfer,a 4-DOF transfer robot is designed in this paper,which consists of parallel four-bar mechanisms.The Jacobian matrix referring to the mapping matrix from the joint velocity to the operating space velocity of the transfer robot can be solved by the differential-vector method.The mean value of the Jacobian matrix condition number in the workspace is used as the global performance index of the robot velocity and the optimization goal.The constraint condition is established based on the actual working condition.Then the linkage length optimization is carried out to decrease the length of the linkage and to increase the global performance index of velocity.The total length of robot rods is reduced by 6.12%.The global performance index of velocity is improved by 45.15%.Taking the optimized rod length as the mechanism parameter,the distribution of the motion space of the transfer robot is obtained.Finally,the results show that the proposed method for establishing the Jacobian matrix of the lower-mobility robot and for the optimization of the rods based on the velocity global performance index is accurate and effective.The workspace distribution of the robot meets the design requirements.