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To assess the nature of a spacecraft's dynamics, it is necessary to develop the simulator of it. However, most of the existing simulators belong to the 3-DOF or the 5-DOF. Until now, the development of the 6-DOF simulator is not satisfying. This paper puts forward a 6-DOF simulator's design which is based on the 5-DOF and uses two tiers to create the freedom in the vertical direction. The feasibility of the design is verified in the end which is composed of the control of the simulator's adjusting levelness system and the calculation of the air film's bearing ability.

Objectives: Premature ovarian failure (POF) has great negative influence on the reproductive ability of childbearing-aged women. Though acupuncture and moxibustion has been regarded as an effective therapy in POF treatment, there is much difference in acupoint selection and combination from different scholars. This research aims to improve acupuncture and moxibustion therapy and mine acupoint selection rules in POF treatment by sorting out and analyzing related clinical studies. Technology or Method: The literature of POF was gathered from databases of PubMed, CNKI, Cqvip and Wanfang. Then acupoint combinaiotn pattern and their correlation were analyzed by the software of TCMISS 2.0. After that, frequency analysis and variable cluster analysis were done by GraphPad Prism 6.0, SPSS 22.0 and HemI 1.0.3 respectively. Results: Study showed that Guanyuan (CV4) and Sanyinjiao (SP6) were the core acupoints in POF treatment with acupuncture and moxibustion and there were three key acupoint combinations: the combination of Guanyuan (CV4)-Zhongji (CV3)-uterus located in the hypogastric region; the combination of shenshu (BL23)Pishu (BL20)-Ganshu (BL18) located in the waist and back; the combinaiton of Sanyinjiao (SP6)-Zusanli (ST36)-Taixi (KI3)-Taichong (LR3) located in lower limbs. Clinical or Biological Impact: This research reveals that POF treatment with acupuncture and moxibustion therapy is characterized by regulation of conception vessel (CV) and thoroughfare vessel (TV), balance of yin and yang, menstruation promotion and blood activation, thus offering helpful reference and objective evidence for future acupoint combination-model construction.

Changes in water storage of the lakes at the Tibetan Plateau are regarded as one of the most critical indicators of regional hydrological response to climate change. Different to the conventional hydrological approaches, in this study, we investigate the storage change of four lakes basing on a conceptual lake storage model and the most recent (2001–2016) available satellite observation that cover the lakes. The water surface areas and water levels are derived from MODIS and LEGOS altimetry data, respectively. Based on the regression function between water level and lake area, the net water budgets of the four lakes are estimated for the period. The results show that the storage of Ziling Co rose the fastest at the rate of 8.24 billion m3/a in the past decades, and the rising rate of Qinghai lake has also reached 4.5billion m3/a. The Ngoring Lake which located in the same region with Qinghai Lake changed fluctuatingly, but the water storage has risen 4.9 billion m3 from 2001 to 2016. The water storage of Dogaicoring QC increased steadily at the rate of 1.2 billion m3/a.

The global maximum frequent itemsets need to be updated because of incremental distributed database. On the base of the fast mining algorithm for global maximum frequent itemsets, an incremental mining algorithm for global maximum frequent itemsets based on health big data was proposed, namely, IMAGMFI algorithm. Firstly, the global frequent items were got. Second, the FP-tree was reconstructed by incremental distributed database. Third, the global maximum frequent itemsets of incremental distributed database were mined. Last, the global maximum frequent itemsets were gained by the strategy of top-down. The experimental results show that IMAGMFI algorithm is effective.

Library personalized information recommendation of big data had becoming an important research task increasingly as the time goes by. The traditional library information recommendation could not satisfy library and users' needs. The paper divided the users into advanced users and ordinary users. The library personalized information recommendation methods and strategy of big data were presented. The experimental results show that the proposed methods and strategy are effective.

In this paper, a profust reliability health state estimation method of the component-level-equipment based on Kalman filter is present. First, the basic idea of state estimation based on Kalman filter is introduced. Secondly, it is deduced the Kalman filter state estimation algorithm. Thirdly, it is introduced to method of health status evaluation based on profust reliability. Finally, a profust reliability health state estimation algorithms of component-level-devices based on Kalman filter is proposed. Combined with gear oil pump application example of dangerous goods disposal system, the feasibility of the method is validated, to broaden the train of thought for health state estimation method of the component level devices.

In this paper, the Ulva prolifera bloom event in the Yellow Sea in summer 2010 is investigated by MODIS (Moderate Resolution Imaging Spectroradiometer) images. We use the FAI (Floating Algae Index) method to detect the distribution of the floating macroalgae from the images. Then we apply the GNOME (General NOAA Operational Modeling Environment) model to simulate the trajectories of the Ulva prolifera in the Yellow Sea. The model results agree well with satellite observations, indicating that the occurrence and movement of the floating macroalgae can be investigated with the combination of GNOME model and satellite data.

In this paper, we introduce a novel independent component analysis (ICA) algorithm, which does not require any preprocessing of the mixed signals (as opposed to most current ICA algorithms). Using a zero-forcing technique, the algorithm performs on-line diagonalization of a matrix whose entries are cross-cumulants of nonlinearly transformed mixtures of source signals. To our knowledge, the proposed approach is the only on-line ICA algorithm that separate mixed source signals without any frequently used preprocessing such as "centering" (subtracting the means from the mixtures) or "sphering" (decorrelation or whitening). Most other higher order cumulants based ICA algorithms involve complicated matrix algebra and lacks the desirable equivariant property which means these algorithms may fail to produce the desired source separation when the mixing matrix is ill-conditioned. The algorithm proposed in this paper, however, is equivariant and the separation performance of the algorithm is independent of the underlying mixing matrix.

The high-risk and complexity of highly dangerous goods destruction need urgently a deep analysis and judgment to the variety health status of destroyed equipment in operation to ensure the operations safety,so the health status monitoring model of destruction equipment was constructed. In this paper it determined the operating status monitoring parameters and equipment unit parameters by reliability and pre-risk analysis, studied the health trends judgment methods of operating status parameters by statistical process control (SPC) and equipment PLC combination, the health status analysis methods of the operating state parameters subsystem related equipment based on the Profust. Finally it composed both analysis methods to judge the health status of destroyed equipment. While it builds the health status monitoring network of destruction equipment, the hardware and software part of actual destruction system. The model provides a new way for the establishment of high-risk operations equipment health status monitoring systems based on PHM.

As for quality problems of automobile punching parts, an inspection method based on Geomagic reversing engineering software is established; basic principle thereof is scanning an automobile punching part by means of a photographic 3D scanner so as to acquire point cloud data and comparing processed point cloud data with standard digitalized samples by means of 3D alignment technology so as to acquire a processing error of the punching part.

This paper provides an exact diversity gain analysis for transmit antenna selection in MIMO-OFDM systems with linear receivers, a topic scarcely addressed in prior literature. In a frequency-selective fading (as opposed to a frequency-flat fading) channel one of either two methods of antenna selection may be applied. We name these methods bulk selection and per-tone selection. From an implementation perspective each method presents a different complexity-performance tradeoff. Through rigorous mathematical derivation, we demonstrate that both methods realize the same diversity order. Moreover, the coding gain realized by the two selection methods is also analyzed and compared through simulation. Overall, this paper confirms the advantage of antenna selection technology in MIMO-OFDM systems, and provides comprehensive guidelines for antenna selection strategies in realistic scenarios, from both the performance and complexity perspectives.

Cooperative transmission by base stations can significantly improve the spectral efficiency of multiuser, multi-cell multiple input multiple output systems. We show that in such systems the multiuser interference is asynchronous by nature, even when perfect timing-advance mechanisms ensure that the desired signal components arrive synchronously. We establish an accurate mathematical model for the asynchronism, and use it to show that the asynchronism leads to a significant performance degradation of existing linear preceding designs that assumed synchronous interference. We consider three different previously proposed precoding designs, and show how to modify them to effectively mitigate asynchronous interference.

Antenna selection is a promising technique for reducing complexity of multiple-antenna (MIMO) systems. In antenna selection, more antenna elements than RF transceiver chains are available for up-conversion and down-conversion. A subset of the available antenna elements is selected and connected to the RF chains. The reduction in the number of RF chains helps to reduce the implementation cost of multi-antenna systems. This paper considers a number of "practical" issues in the implementation of such systems. We discuss schemes for the channel estimation for all all antenna elements, and show that antenna selection is robust to channel estimation errors. RF preprocessing can be used to enhance the array gain of antenna selection schemes; the performance is robust to errors in the RF elements used for the preprocessing Finally, we analyze both bulk selection and per-tone selection in MIMO-OFDM systems, and show that the former is usually preferable. Results from simulations with 802.11n-compliant systems, and capacity results in measured channels show that SNR and capacity gains can be achieved with antenna selection in practical situations.

In this paper, we propose a crosslayer approach that explores Tomlinson-Harashima precoding (THP) at the physical layer to reduce the multiuser scheduling burden at the MAC layer, and improves the sum rate of the downlink multiuser MIMO system. Our proposed scheme is further evaluated with imperfect feedback, obtained by the long range prediction (LRP) technique. Compared to some existing scheduling schemes, the proposed scheme approaches the performance upper bound in certain scenarios, while incurring much less computation complexity. Significant gains are still maintained with imperfect channel state information (CSI), fed back at a rate much lower than the data rate

The diversity-multiplexing tradeoff for MIMO point-to-point channels and multiple access channels are first proposed and studied in [4][5]. While the optimal tradeoff curves for MIMO channels have been explicitly explored, those corresponding to some practical MIMO schemes are still open. One such example, as mentioned in [4][5], is the diversity-multiplexing tradeoff problem for ordered successive interference cancellation (SIC) receivers, which is the focus of this paper. In literature, the impact of the optimal ordering on the diversity order for V-BLAST SIC receivers is analyzed for 2-layer scenarios [2][3][6], but only conjectured for larger number of layers through numerical results [2][7]. In this paper, based on a novel geometrical analysis, we prove that under general settings, any ordering rule for a V-BLAST SIC receiver will not improve its performance regarding diversity-multiplexing tradeoff. Furthermore, extending the study to multiple access channels, we show that the two extreme points of the tradeoff curve remain unchanged regardless of ordering, which motivates us to predict that the whole tradeoff curve is the same as that of fixed-order detectors.

Different from conventional multiuser scheduling schemes targeting on optimizing the physical layer performance criteria such as Shannon capacity and error probability, in this paper we propose a family of new scheduling methods that take the packet throughput in upper-layer protocols into considerations. This new performance metric appears to be an elegant combination of spectral efficiency and channel reliability, which are two usually competitive performance indicators for practical transmitters and receivers. Our results show that regarding the packet throughput, the proposed schedulers may result in great performance advantage over conventional schemes, especially at low to intermediate SNR. Furthermore, the amount of system delay for each user is investigated together with packet throughput for scheduling algorithm designs. A novel scheduler, considering both system performance and user delays, is then proposed, and the corresponding delay-throughput tradeoff curve is drawn, which actually provides a useful and flexible platform to evaluate any scheduling schemes, if both factors are under concern

Motivated by some properties of the determinant of Hermitian positive definite matrices, this paper develops some fast transmit antenna selection algorithms for MIMO systems, based on instantaneous channel information or channel statistics for a correlated fading channel. The performance of these algorithms is evaluated in terms of both the resulting system capacity and error rate. The novel G-circles method can achieve many advantages over other existing algorithms.

In the context of antenna selection for MIMO diversity systems, the problem of optimal diversity order is well addressed. On the other hand, the diversity order achieved by antenna selection in spatial multiplexing systems, especially those exploiting practical coding and decoding schemes, has not been rigorously analyzed thus far. In Zhang, H, et al. (2005), we propose a new geometrical framework for theoretically analyzing the achievable diversity order when L = 2 transmit antennas are selected for an N/sub R/ /spl times/ N/sub T/ SM system with linear receivers. In this paper, we extend it to the general scenarios with 2 /spl les/ L /spl les/ N/sub T/, and both linear and decision feedback receivers are considered. A diversity order of (N/sub T/-L+1)(N/sub R/-L+1) are rigorously shown to be achievable by the optimal selection, which was previously partly conjectured by other researchers through simulation results.

A new conceptual spaceborne radar altimeter is introduced, which can be used not only for oceanic observation as a conventional altimeter but also for ice and land topography mapping. This new sensor is different from the recently proposed scanning altimeter and SAR altimeter. The basic principle of this sensor can be concluded as: (1) off-nadir looking, (2) model-free tracker based on off-set center of gravity (OCOG) algorithm, (3) synthesize the aperture along azimuthal direction, (4) Interferometric information obtained through two antennae and height value corresponding to pixel can be derived. The authors introduce the system design and data processing. They propose a small satellite constellation for global topography mapping.