Advanced Materials Research Vols. 314-316

Abstract: Two kinds of oligofluorenes containing acetylene units are synthesized by Sonogashira coupling reaction. naphthalene and anthracene are co-polymerized with ethynylfluorene, respectively. The structure and properties are characterized using NMR, UV-vis spectroscopy, elemental analysis, DSC and photoluminescence. The oligomers are soluble in common organic solvents such as benzene and easily spin-coated onto glass substrates. The products yield strong emission differing from blue to green-yellow, and red-shift are suppressed with the growth in size of co-monomers.

Abstract: This paper proposes a new algorithm of gravity-like mechanism and a multistage buffer for the car sequencing problem. The algorithm utilizes the principle of gravity and codes the cars as particles, which can achieve the ordering by the gravity of particles themselves in the sequencing buffer. The Petri net model of the Buffer is proposed and a car sequencing problem is analyzed as an example, the results prove that the algorithm and the buffer can perform well in car sequencing problem.

Abstract: Abstract: The evolution of the screening efficiency for the probability screen was given in this paper. Trispectrum based on AR model was estimated with the vibration signal obtained from the probability screen. The relevance between trispectral slices and screening efficiency was analyzed qualitatively. The evolution of screening efficiency was also discussed in detail with a statistical quantity, i.e., kurtosis(K); In addition, the relationship between the correlation dimension and screening efficiency was analyzed quantitatively. The results show that the relevance between the spectral characteristics and screening efficiency is consistent with the relationship between the correlation dimension and screening efficiency.

Abstract: A progressive damage and failure model for fiber reinforced laminated composites is developed in combination of finite element procedure and micromechanical model based on a unit cell. The micromechanical model can be used to evaluate failure criteria at the micro-level with fiber and matrix material properties. Once either of the constituents has damaged, the corresponding material properties are degraded by the damage factor. The micromechanical model and the damage theory are implemented in the finite software ABAQUS by using the user material subroutine UMAT and VUMAT, to model the damage progression and compute the ultimate strength of the composite laminates containing a hole. The predicted strengths for this model is compared with the experimental results, and a well agreement in the simulation and experimental resulted is revealed.

Abstract: The data processing and conversion plays an important role in RP processes in which the choice of data format determines data processing procedure and method. In this paper, the formats and features of commonly used interface standards such as STL, IGES and STEP are introduced, and the data conversion experiments of CAD models are carried out based on Pro/E system in which the conversion effects of different data formats are compared and analyzed, and the most reasonable data conversion format is proposed.

Abstract: As a new manufacturing paradigm, cloud manufacturing (CMfg) is proposed to realize the added-value and on-demand use of manufacturing resource and ability in the form of manufacturing services. Considering that there always exist correlations among cloud services (CS), which affect the cloud service composition (CSC). Hence, how to mine the correlations among CSs and apply them to CSC is a key issue for realizing the added-value. This paper presents a framework for correlation relationship mining for CSC. Four function modules for mining correlations among CSs are analyzed, and the involving key issues were preliminarily discussed as well.

Abstract: At present, gas disaster is one of the main problems for Chinese coal industry. The prevention and control of gas accident is an important part of coal mine enterprise production safety. This paper uses wireless sensor network to collect the coal mine gas concentration parameter, transmits and stores the data to the server of gas monitoring system by information fusion of sink, and synchronously displays the data to the client in the state of three-dimensional space. When the gas concentration of monitored coal mine roadway is greater than the limit, the sound and light alarm will be trigged and the alarm area will be displayed. In the meantime, the information of contingency plan will be provided. The system gives a strong technical support for the early warning and controlling of gas disaster and provides a reference for the prevention of gas accidents in coal enterprises.

Abstract: In this paper, the surface shapes of roller followers and spiral groove are researched. General surface equations of different types of roller follower are studied. According to the ordinary equation of spiral groove, the region shape between roller follower and spiral groove is discussed with the Hertz contact theory. By researching on the common mesh type, we can conclude that the gap shape function is elliptic equation.

Abstract: Because of the self-balancing and self-organizing properties of Bucket Brigades, it is well known by most scholars both at home and abroad. Ideally it is proved that higher productivity and production stability can be obtained through bucket brigade lines. However, return velocities must be considered in realistic conditions. We proved that bucket brigade lines with the same return velocities would be self-balanced, the task-delivering places approximates to the ideal balance point if the return velocity is large enough .At the same time the smaller return velocities will result in lower productivity.

Abstract: This paper aims to investigate the workgroup-based manpower planning for multi-type staff collaboration. For customization-based equipment making companies, multiple types of staffs which have different working efficiencies often exist. This situation is even complicated by the working groups which have master-apprentice constraints. Due to the complexity of the problem, this paper not only considers the staffs’ salaries and employment/unemployment costs, but also takes the technique inheriting and employee stableness into consideration. Through establishing the dynamic planning model which reflects staffs’ employing and working types, the configuration results of human resource are obtained and recommended to this kind of companies.