松景公司推出多款多功能MP3机——办公新宠“数位通”

松景公司近期将在国内市场推出一种价格千余元的被称为“数位通”的DAA。

A K-Median Facility Location Agent for Low-Cost Service Selection in Digital Community Network

With the increasing number of web services, it becomes a difficult task for an ordinary user to select an appropriate service. Hence, it is conventional that users in a digital community network take part in a collaborative mechanism for the purpose of service selection. The participation usually brings unnecessary burdens for users, such as giving opinions, storing service information. Extra communication overhead hinders the performance of the network. Thus, the community administrators are facing a problem of how to obtain an overall service selection result for the whole community readily and effectively. To address this problem, we present a k-median facility location agent model. The model analyzes the procedure of service selection through five entities and six types of messages. Two algorithms are elaborated in pursuit of a global optimization concerning connection costs between users and facilities where services are deployed. To evaluate our model, we conduct extensive simulations and present a detailed analysis of the simulation results.

Accounting for Differences： What Impact do Decile and Gender Have on NCEA Level Three Accounting Results？

This paper examines the effect on rates of achievement of the interaction of student gender and school socioeconomic status, using ordinary least squares and probit regressions. The data used is school achievement by students taking externally assessed accounting standards in their final year at New Zealand secondary schools, and covers the period 2004 to 2008. The paper concludes that the interaction of gender and school decile have a significant impact on achievement rates for Maori, Pacific Island and Asian girls relative to Maori, Pacific Island and Asian boys in low decile schools. A secondary contribution of this paper is to demonstrate that comparing the achievement of gender or socioeconomic status groups in isolation is insufficient when examining academic performance and evaluating subject curriculum. Interactions between variables need to be considered, whether they be gender and decile as this paper examines, or other variables not examined within this paper.

Improved estimation of rotor position for sensorless control of a PMSM based on a sliding mode observer

This work proposes a new strategy to improve the rotor position estimation of a permanent magnet synchronous motor(PMSM) over wide speed range. Rotor position estimation of a PMSM is performed by using sliding mode observer(SMO). An adaptive observer gain was designed based on Lyapunov function and applied to solve the chattering problem caused by the discontinuous function of the SMO in the wide speed range. The cascade low-pass filter(LPF) with variable cut-off frequency was proposed to reduce the chattering problem and to attenuate the filtering capability of the SMO. In addition, the phase shift caused by the filter was counterbalanced by applying the variable phase delay compensation for the whole speed area. High accuracy estimation result of the rotor position was obtained in the experiment by applying the proposed estimation strategy.

Simulation study of blast fume diffusion characters of driving face

Based on FLUENT software, studied the blast fume diffusion characteristics of a driving face under 8 situations, and analyzed the influence to fume diffusion of different drift length and different ventilation pipe outlet positions. Through regression analysis, functions of ventilation time to the drift length and ventilation pipe outlet position was obtained.

Ship Waste Management in the Port of Igoumenitsa, Greece

Port of Igoumenitsa in Greece is one of the most important Ports in European Union and enjoys a privileged position being located at the starting point of Egnatia Motorway The Port is one of the largest passenger ports in the East Mediterranean Sea basin, which, handles around 1,000,000 passengers per year for international destinations. The paper investigates current waste management and disposal options for ship generated waste and the associated impact of the waste for port. Data about the ship traffic were provided by the Port Authority and about the amount and characteristics of the wastes by the contractors for the disposal of the ship generated waste. It was concluded that all vessels should be encouraged to use the reception facilities and should pursue a waste reduction strategy and the port authority to provide adequate recycling facility. An electronic recording data system has to be adopted for better evaluation of the performance of the system. This system must record the deliveries for every ship in the port, the amount and the type of wastes are generated. Also must provide information about the maximum storage capacity of waste on board and about management of waste treatment options by the ships.