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In deep lunar soil sampling, the drilling mechanism is driven by the loading wire rope through a driving mechanism. This paper is aimed at establishing an accurate dynamic model of the removable loading wire rope and analyzing its influence on the drilling process. In the process of drilling, there exists material transportation at the boundaries, so the length and mass of the upper and lower wire...
Ensuring aircraft stay safely separated is the primary consideration in air traffic control. To achieve the required level of assurance for this safety-critical application, the Automated Airspace Concept (AAC) proposes a network of components providing multiple levels of separation assurance, including conflict detection and resolution. In our previous work, we conducted a formal study of this concept...
Gift cards are widely used by many enterprises nowadays for products promotion. Gift cards are used not only for a basket of goods, but also for some specific kinds of goods. In this paper, we characterize consumers' purchasing behavior according to descending consumers' reservation price, then develop a model to derive the optimal purchase amount threshold and gift card value. We find that offering...
E-commerce enterprises concentrate their efforts on the main business, and outsource their logistics business to the professional third-party logistics company by signing a contract. This paper analyzes the most of e-commerce enterprises why to outsource their logistics business in China and elaborates the advantages and disadvantages of logistics outsourcing in the e-commerce enterprises. Based on...
Nowadays, mesh-based live streaming on P2P network is becoming more and more popular because of its scalability, robustness and no additional infrastructure requirement (e.g. CoolStreaming, PPlive, PPstream, Gridmedia). How to design a high fluency and small delay system is a challenge task. In this paper we analyze the impact of playback lags between peers on the playback fluency via a simple stochastic...
This paper discusses the application of the time series AR (Auto Regressive) model in price forecast. It focuses on feasibility from the theoretical perspective and then proves the advantages of the application in price forecast by case studies. It shows that AR model is applicable in the forecasts of the trends in price statistics, the evaluation of physical conditions and the
In order to improve the structural performance of a five-axis gantry milling machine, a design idea of adopting parallel optimum design for key components and complete machine was investigated. Using CAE (Computer Aided Engineering) software, the finite element analysis model of the five-axis gantry milling machine key components and the complete machine were established. Then the static stiffness...
This paper, beginning with studying the characteristics of the war from a complex system, in accordance with discrete events system modeling and simulation, respectively, from the basic discrete event system specification, as well as the architecture of the models and simulation engine two aspects, researched on modeling method based on DEVS war simulation models of complex systems architecture. Contribute...
The volatility of stock price states the uncertainty of the future price movements, that is risk. By means of the ARCH and its modified models, this paper presents a verification analysis of the volatility heteroscedasticity and the resilience to external shocks for China stock market in the past three years based on the stock index of SSE180, SZSE40, Coal, Petroleum and Finance sectors. The study...
Nowadays, web portals have become a useful way for high-tech information centers providing information services for high-tech enterprises. The importance of evaluating the information service quality of these Web portals has been recognized by both information service researchers and practitioners. By applying an analytic hierarchy process (AHP) approach, a hierarchical structure evaluation criteria...
For research on the aerodynamic characteristics of structures undergoing the acting of the sudden-change flow, the wind tunnel experiment for simulating the sudden-change airflow was introduced in this paper. Firstly, a profile of downburst gust was simulated using an active control wind tunnel. Secondly, the approach of change-step change airflow was utilized to simulate the time history of sudden-change...
Modal analysis of satellite system is the basic requirement for the satellite structural design. The theory of normal modes is analysed rounded in this paper. And the finite element model of a small satellite, of which the monolithic structure is honeycomb sandwich plate, is established by using the finite element analysis software PATRAN/NASTRAN. Furthermore, the equivalent model for honeycomb sandwich...
Perceived predominant melody of music is the most convenient and memorable description and can be used for content-based music retrieval. However, including human voice and multiple musical instruments playing together, it is difficult to extract a predominant contour of pitches directly from MP3 music recordings. In order to build a similarity music melody model, several audio files, whose melody...
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