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Two line element (TLE) released by the North American Aerospace Defense Command (NORAD) is widely used by aerospace workers, and the matched SGP4/SDP4 (Simplified General Perturbation Version 4/Simplified Deep-space Perturbation Version 4) model is used to propagate it. Nevertheless, no corresponding information about its accuracy and covariance is clearly given, thus the application of the TLE data is greatly restricted. In this paper, the determined and predicted orbits are compared to generate the orbit error data, based on the historical TLE data obtained from the Space-Track website and the SGP4/SDP4 model. By dividing different time bins, the fitting coefficients of the variation of orbit prediction error with time are given for each space object, and the characteristics of the error evolution are further discussed for the different types of orbits. The mean analytic model of the orbit prediction error evolution with time is given respectively for the four orbit types of space objects, which provides a valuable reference for extending the application of the TLE data.

In this paper, methods of energy transformation to reduce OPEX for remote area are introduced which can be divided into efficiency improving and consumption reducing.

Real-time control of urban fire water supply system status, to ensure the safety and reliability of fire fighting and rescue is of great significance. This paper proposes a method of monitoring the status of urban firefighting water supply system based on water pressure mean. It theoretically analyzed the principle and realization method of sliding filter for hydraulic pressure sensor, and emphatically studied the time domain law of hydraulic pressure signal. The differences in the water pressure mean values in different states of water system were studied in detail. Finally, the effectiveness of the algorithm was verified by the actual leakage test. The results show that the method can obtain the status of the fire water supply system accurately, and monitor the abnormal state of the system in real time, which provide a reliable information guarantee for the fire rescue operation command.

This paper studies the characteristics and design concept of low-speed high-torque direct-driven PMSM with fractional-slot concentrated winding used in coal mine belt conveyor system. The fractional slot concentrated winding PMSM with high efficiency, high power density and simple windings type is used widely, and more attention is paid to the influence of cogging torque with different slots and poles, but less attention is paid to the effect of the different between different stator conductor turns loss on open-slots motor and rotor magnet loss caused by harmonic field. In this paper, taking a 500kW 60RPM 1140 V low speed permanent magnet direct-driven motor as an example, it presents that the difference between different stator conductor turns loss of multi-polar few slot motor and the rotor magnet loss by the EFA simulation and temperature field calculation, which are not uniform and easily overlooked, will be leaded to serious temperature rise problems. A new rotor topology structure design and some measures on how to reduce stator copper loss and rotor eddy current loss are propose. The prototype machine was developed and tested to validate the feasibility and correctness of design and analysis.

To reduce the resource consumption in traditional software IPv6 Internet protocols based on embedded system, a data transmission hardware scenario of reduced IPv6 protocol with optimized cache structures based on the FPGA is designed using Verilog HDL. This scenario implements the function of the Transport Layer and the Network Layer on FPGA and uses the function of the Data Link Layer and the Physical Layer on the DM9000A chip, which can perform stateless auto-configuration, address resolution, echo response and UDP transmission. To improve the transmission efficiency, a low-resource-consumption and self-managed cache structure is designed to manage the Neighbor Cache, the Prefix Table and the Default Router Table. In the IPv6 network test, the design can configure itself and its data rate exceeds 28Mbps, which can realize real-time video stream, audio stream and other data transmission in Network of Things applications in IPv6 network.

We investigate the molecular beam epitaxy growth of metamorphic InxGa(1-x)As materials (x up to 0.5) on GaAs substrates systematically. Optimization of structure design and growth parameters is aimed at obtaining smooth surface and high optical quality. The optimized structures have an average surface roughness of 0.9-1.8 nm. It is also proven by PL measurements that the optical properties of high indium content (55%) InGaAs quantum wells are improved apparently by defect reduction technique and by introducing Sb as a surfactant. These provide us new ways for growing device quality metamorphic structures on GaAs substrates with long-wavelength emissions.

Quality of service (QoS) of wireless sensor networks (WSNs) communications has become one research hotspot, especially for the emergency data transmission. Many researchers focused on developing WSN routing algorithms to guarantee the transmission QoS, but less research has been concerned in the mobile user equipment (UE) acting as a gateway for WSN data transmission. In this paper, we first propose that the system application requirement for WSN, where UEs of mobile cellular network (MCN) act as sensor nodes and gateways for WSN. And then, we investigate QoS key technical challenges in the convergent networks of MCN and WSN. Finally, based on an analysis of technical challenges, we discuss the research points of QoS for WSNs.

Interpreters are expected to have an advanced command of not only the vocabulary and grammar of their working languages, but also the pragmatic norms that speakers of their working languages employ in communicative interactions. The aim of this paper is to explore the perceptions and practices of interpreters in relation to intercultural pragmatics at work in healthcare interactions. The paper employs two theoretical frameworks: the first is based on interpretations of behavior according to speakers' discourse-pragmatic features as representative of “high” or “low” context cultures (cf. Hall 1976); the second applies Celce-Murcia's (2007) more refined notion of “communicative competence.” The data sample of this paper focuses on cultural-pragmatic features of two linguistic and cultural groups – 25 Chinese speakers and 24 English speakers – and contrasts their selected responses to five features of Chinese-English interpreted healthcare interactions. Responses from 33 Chinese-English interpreters are matched against those from speakers of the two groups to examine the degree of congruence that interpreters have with the self-reported (para-)linguistic behavior of the two groups of speakers, for whom they interpret. This study shows that the self-reported (para-)linguistic behavior of both groups is determined by their adoption of a particular approach (doctor- vs. patient-centered approach) and other micro-level features (perceived time constraints, different notions of “small talk”) that limit elaborate pragmatic enactments. Over-arching cultural-pragmatic models based on “high” (or “low”) context communication, or “vertical” (vs. “horizontal”) hierarchical perceptions of role and status appear to have limited application to the data. Instead, local features specific to the healthcare situation co-determine both English and Chinese speakers' responses to questions about their use of pragmatics. Findings indicate that interpreters attend to each group's enactment of pragmatic features and, as expert language users, are able to recognize features and components of interactions and their functions to a greater degree than the Chinese and English speakers.

A resonant-cavity enhanced reflective optical modulator is designed and frabricated, with three groups of three highly strained InGaAS/GaAs quantum wells in the cavity, for the low voltage and high contrast ratio operation. The quantum wells are positioned in antinodes of the optical standing wave. The modulator is grown in a single growth step in an molecular beam epitaxy system, using GaAs/AIAs distributed Bragg reflectors as both the top and bottom mirrors. Results show that the reflection device has a modulation extinction of 3 dB at -4.5 V bias.

GPS repetition measurement tbta in Qinghai-Xizatlg (Tibetan) area in 1992 and 1994 have been used to determine the change rates of seven bascline vectors of Lhasa-Wenquan, etc. It is the first time to obtain the direct observation results of the large-scale crustal horizontal motions in this area. Thesc preliminary results also for the first time provide the direct observation evidence for some important geophysical and geological viewpoints, such as the northward gradual reduce of the effect of the northward push-pressing to Eurasian continent by Indian Plate in the Qinghai-Xizang area, having a southward strike slip movement of the Chuan-Dian diamond block, etc.

The LCD devices exists motion blur problem, which is hard to resolve and occurs when render the motion images. This paper presents a novel method try to improve the LCD motion blur phenomenon from the view of system identification. The method adopts the Volterra nonlinear system based on the N-VSSLMS (Normalized Variable Step Size LMS) algorithm to approximate the sinc−1 system, in which we can construct a feasible inverse system of the LCD motion blurring system. Simulation results demonstrate the method can improve the LCD motion blur phenomenon obviously, the performance of the proposed method is better than the sinc−1 system, and it can be implemented in hardware easily.

With the rapid development of wireless communication technologies in recent years, there have been great advances in the test technology to meet with new communication systems. Cloud testing, as a new technology to integrate network, software, computers, and virtual instrument together, has emerged to be widely used for co-simulation and distributed testing. In this paper, we firstly introduce the current application situation of the wireless communications test technology and the architecture of “Cloud Testing”. And the key technologies for cloud testing are carefully discussed which lead to some useful conclusions. Finally, the application prospect of this new test technology is given.

A novel Through Silicon Via (TSV) structure to mitigate the high electrical loss at high frequency is presented here. At low frequency, the loss for the TSV is caused mainly by the material loss of the Silicon (Si) substrate due to its low resistivity. However, at millimetre wave (mmWave) frequency range, especially above 50GHz, in addition to the insertion loss, the return loss due to impedance mismatched becomes significant. These losses become a serious setback for the Si Interposer for the mmWave applications. To overcome these losses, polymer cavity formed in the Si substrate with TSV is developed. The polymer has lower loss tangent and lower dielectric constant than Si. These properties can help to reduce the insertion loss and the return loss. Depending on the requirement, multiple set of TSV can be formed on the polymer cavity to provide higher interconnect density. From the simulation results, the new polymer cavity TSV at 100GHz have an insertion loss and return loss of ∼0.2dB and less than −25dB, respectively. On the other hand, conventional high resistivity TSV has an insertion loss and return loss of ∼1.4dB and more than −10dB, respectively, at the same frequency. For higher frequency range, the performance of the polymer cavity TSV is approximately consistent, but the conventional TSV deteriorated drastically. In this paper, the design, fabrication process and the measurement results are presented. The prototype polymer cavity TSV via-line-via test vehicle has a measured insertion loss of less than 1dB and a return loss of better than −10dB through the frequency range up to 110Gz.

Based on a survey, this article made an empirical study on the determinants of job satisfaction from the angle of fit theory. The article mainly analyzed the extent to which job satisfaction might be determined by the person-organization fit, person-job fit and its sub-concept. The article also compared the result with related results. Finally, a satisfaction model based on the fit theory was established.

DFT-S-GMC (DFT-spread generalized multi-carrier) has been confirmed as one of the uplink transmission schemes of the broadband wireless multimedia (BWM) of China. In this paper, the PAPR of DFT-S-GMC is studied, and the theoretical analysis proves that it's not a pure single carrier system. A new pulse shaping filter is proposed for further reducing DFT-S-GMC PAPR. The simulation results show that the performance improvement attained by utilizing the new method.

A novel conceptual physical model is proposed for multilevel spiral inductors on silicon substrate where in the metal layers are connected in parallel through dense vias. The model takes into consideration the mutual inductance, and the inter-metal capacitance between different metal spirals. An excellent agreement between the simulated S-parameter from the extracted model and measured data is obtained. It is useful for optimization of multi metal inductor design.

In this paper, the thickness of silicon substrate with backside metallization effects on the inductor performance were investigated, the experimental results showed that thinner substrate with backside metallization resulted in smaller inductance and slightly higher resonant frequency. For circular spiral inductor with substrate thickness of 50mm, the inductance L with eight turns would be degraded 22% compared to the counterpart of substrate thickness of 150mm, correspondingly, the quality factor Q fallen down 16%. The measured results also showed that the inductor performance with substrate thickness of 150mm and above has not been affected by substrate thickness. Therefore, to optimize inductor performances involves trades-off between substrate skin effect and thermal conductivity in power applications. It is believed that the demonstrated results are useful for RF integrated circuits (RFICs) design and packaging.

We obtain low-density charged InAs quantum dots with an emission wavelength below 1 mu m using a low InAs growth rate. The quantum dots have a bimodal size distribution with an emission wavelength of around 1340 nm and 1000 nm, respectively. We observe the photoluminescence of the singly charged exciton in the modulation doped quantum dots in 77 K.

A bilayer stacked InAs/GaAs quantum dot structure grown by molecular beam epitaxy on an In0.05Ga0.95As metamorphic buffer is investigated. By introducing a InGaAs Sb cover layer on the upper InAs quantum dots (QDs) layers, the emission wavelength of the QDs is extended successfully to 1.533 mu m at room temperature, and the density of the QDs is in the range of 4 x 10(9) -8 x 10(9) cm(-2). Strong photoluminescence (PL) intensity with a full width at half maximum of 28.6 meV of the PL spectrum shows good optical quality of the bilayer QDs. The growth of bilayer QDs on metamorphic buffers offers a useful way to extend the wavelengths of GaAs-based materials for potential applications in optoelectronic and quantum functional devices.

Electrically driven single photon source based on single InAs quantum dot (QDs) is demonstrated. The device contains InAs QDs within a planar cavity formed between a bottom AlGaAs/GaAs distributed Bragg reflector (DBR) and a surface GaAs-air interface. The device is characterized by I-V curve and electroluminescence, and a single sharp exciton emission line at 966nm is observed. Hanbury Brown and Twiss (HBT) correlation measurements demonstrate single photon emission with suppression of multiphoton emission to below 45% at 80K

National Natural Science Foundation of China 60607016 60625405National Basic Research Programme of China National High Technology Research and Development Programme of China Supported partly by the National Natural Science Foundation of China under Grand Nos 60607016 and 60625405, the National Basic Research Programme of China and the National High Technology Research and Development Programme of China.