Advanced Materials Research Vols. 433-440

Abstract: A novel hybrid-stator bearingless switched reluctance motor (HSBSRM) was researched. After analyzing magnetic linkage characteristics, its mathematical model was built with finite element method, and a radial displacement self-sensing method was designed. This hybrid stator motor has unique advantages compared with those traditional bearingless switched reluctance motors, so radial displacement self-testing techniques have important research significance and practical value. Simulation and experimental results validated the proposed methods.

Abstract: In order to be compatible with the legacy 802.11, there are two major MAC behaviors, High-throughput (HT) and non-high throughput (non-HT) in the 802.11n. In this paper, we analyze and compare the energy efficiencies of different MAC behaviors in 802.11n based on the Bianchi model and our previous works [6] to evaluate the performance of the different MAC behaviors regarding HT and non-HT. Studies show that owing to the large power consumption in HT, it is not suitable for limited power devices to carry WWW traffics by MIMO transmissions. However, if large file transmissions by FTP are considered, the energy efficiency in HT MAC can be very high due to the large aggregated frame size. It is especially true when the number of active stations is large. Our works can indicate the mobile devices with limited battery endurance to reduce the energy consumption by the decision to enable HT mode or not for the transmission of data frames based on the cross-layer integration.

Abstract: A framework for determining optimal period and cost in extended warranty is proposed in this paper. The optimal period and cost is derived from two-dimensional delay time model. Two-dimensional delay time model is governed by age and mileage. Age and mileage gives effect for the rate of defect arrival λ. The steps for obtaining the model to estimate the optimal period cost of extended warranty is presented. It starts from modeling the defect arrival rate, the impact of preventive maintenance toward the defect arrival rate; determine the delay time distribution, data analyzing and the last optimal cost and period estimation for extended warranty.

Abstract: Presented is a multiple model soft sensing method based on extreme learning machine (MELM) algorithm, to solve the problem that single ELM model has lower predictive precision and over-fitting problems. The method adopts Gaussian process to choose secondary variable for soft sensor model. Then, samples data are divided into several groups of data by adaptive affinity propagation clustering, and the sub-models are estimated by ELM regression method. Finally, ELM is regarded as output synthesizer of sub-models. The proposed method has been applied to predict the end point of crude gasoline in delayed coking unit. Compared with single ELM modeling, the simulation results show that the algorithm has better predictive precision and good generalization performance.

Abstract: Aiming at the actual situation in case of high-rise student apartment fire, this paper sets an evacuation scene and evacuation parameters, applied BuildingExodus Evacuation Model software, and calculated the dynamic changes of evacuation time and evacuation amounts of people in each access of the building, which accords with the result of fire evacuation drill. It is concluded that it is reasonable and practicable using model software to simulate evacuation time for each floor, and the result can be a substantial reference for actual evacuation time in case of fire.

Abstract: Mobile racks are used broadly in warehouse, especially in those with low items and large stock-keeping unit (SKU). However, contraction between storage capacity and rack efficiency may restrict the usage of mobile racks. Such an example in medicine industry was offered in this paper. Using Witness simulation Software, a model has been developed for medicine warehouse with mobile rack system. Simulations have been executed to analyze rack efficiency in five different scenarios. All scenarios embodied more or less low efficiency and long line in front of buffers. Results indicated that efficiency relies on policies of order-picking and space allocation. It can also be concluded that the minority items of small quantities and low frequency may decide the performance of the whole system.

Abstract: In this paper we present the Multiple Sub-Filters (MSF) parallel structure, Least Mean Square (LMS) adaptive algorithm, for Stereophonic Acoustic Echo Cancellation (SAEC). The convergence performance of the MSF parallel structure has been studied for two types of algorithms namely; different error algorithm and common error algorithm and has been compared with conventional echo canceller via computer simulations. Simulation results show that MSF with both adaptation algorithm provide better convergence speed as compared to the conventional SAEC realized by a Single Long Filter (SLF).

Abstract: Microsoft word is widely used for word processing and document production. So the loss of the Word file would be great damages for their owner. File carving can reconstruct files based on their content and their own structure rather than using the metadata of the file system. The existing methods do not work very well on carving fragmented Word files. This paper presents a Microsoft Word documents carving method based on interior virtual streams. Firstly, we locate the header section and control streams-SAT to construct the framework for a Word file; then find its fragment regions by utilizing the framework information, and use the sequential hypothesis testing on the data streams in the fragment region to detect the fragment point. Based on DFRWS data sets and real data set, experiments show our method can automatically carve continuous and fragmented Microsoft word file. Moreover, the comparative experiments demonstrate that the proposed method is better than others’ in accurateness and effectiveness.

Abstract: This paper mainly introduces a new kind of adaptive control hexapod bionic rescue robot. From the angle of bionics, hexapod robot’s gait algorithm which is based on hexapod cockroach is studied. It uses the adaptive control algorithm to convert hexapod robot's gait algorithms under the different circumstances and sets up D-H coordinate of robot’ssingle leg to analyze the single leg’s kinematics.

Abstract: With the development of information technology for equipment investment, loss of large number of teaching support materials consumption experiments, the establishment of education system simulation, simulation laboratory teaching has become a hot issue. This article discusses the design of marine ships built control system and simulation platform. The platform can be used for ship turbines comprehensive experiment. It has integrated a variety of experimental features.