基于SIR-1000W的多测点同时基鱼雷噪声测量系统

结合实际科研课题基础研究项目鱼雷噪声数据（含振动噪声、流噪声、螺旋桨噪声、辐射噪声等）获取需求。建立了基于SONYSIR-1000W数字记录仪的多测点、同时基的鱼雷噪声测量系统．介绍了系统的主要功能、设备组成、工作原理等。并给出了系统达到的主要技术指标及实航试验结果．

潜艇噪声振动同时基测量与噪声源分析技术

本文介绍了潜艇噪声振动同时基数据采集的测量技术 ,通过潜艇噪声振动同时基数据分析 。

Analysis of Gene Expression of Seven Isoforms of ADP-glucose Pyrophosphorylase in Rice Endosperm under Different Temperature Conditions

[Objective] This study aimed to analyze the effects of temperature on the expression of AGPase isoform genes in rice endosperm during milk stage. [Method] Different temperature treatments （33 and 25 ℃ of daily mean temperature for high and normal temperature treatments, respectively） and the real-time fluorescence quantitative PCR （ FQPCR） were used to analyze the expression patterns of seven isoforms （AGPS1, AGPS2a, AGPS2b, AGPL1, AGPL2, AGPL3 and AGPL4） of ADPglucose pyrophosphorylase （AGPase） which was the key enzyme in starch synthesis and metabolism in rice endosperm of two rice varieties Teqing and Thai Fragrant Rice. [Result] The AGPase isoforms AGPS2b, AGPL2 and AGPL3 had much higher expression than the other four isoforms, thus they were thought to be the main expression patterns of AGPase in rice endosperm. The relative expressions of AGPL2 was the highest among all the isoforms. The relative expressions of AGPS2b, AGPL2 and AGPL3 were higher in the normal temperature treatment than in the high temperature treatment in both rice varieties. The relative expression of the three enzyme genes in milk stages in Teqing was higher than those in Thai Fragrant Rice under different temperature treatments. [Conclusion] This study provides a theoretical basis for further use of molecular biology techniques to cultivate stable high-quality rice varieties.

Optimal Time and Bandwidth Allocation Based on Nash Bargaining Solution for Cooperative Cognitive Systems

In this paper,we propose a cooperative spectrum sharing strategy based on the Nash bargaining solution.Specifically,the primary system leases a fraction of its transmission time to the secondary system in exchange for cooperation to improve its transmission performance.To gain access to the spectrum of the primary system,the secondary system needs to split a fraction of its transmission bandwidth to help to forward the primary signal.As a reward,the secondary system can use the remaining bandwidth to transmit its own signal.We find a unique solution for this time and bandwidth allocation using the Nash bargaining solution.Simulation results demonstrate that the performance of the primary and secondary systems can both be improved by the proposed spectrum sharing strategy.

基于UKF的雷达和机载ESM扩维跟踪

为有效提高异类传感器融合跟踪的效果,提出了一种基于UKF的雷达和机载ESM扩维跟踪算法。首先将目标和机载ESM的状态信息组合起来,形成一个高维的状态向量,从而有效抑制滤波中GPS定位误差所带来的影响;接着在此基础上采用UKF来实现目标的定位跟踪,以求进一步减小扩维后线性化误差加大等问题的影响。仿真结果表明,该算法可更好地实现对目标的定位跟踪。

Simultaneous determination mercury species of Su-He-Xiang-Wan in rat tissues by HPLC-CVG-AFS

A simple and sensitive high performance liquid chromatography-chemical vapour generation-atom fluorescent spectrometry （HPLC-CVG-AFS） method was developed and validated for simultaneous determination mercury species in Su-He-Xiang-Wan （SHXW） and in tissues of rats, respectively. The species of mercury were separated by a Venusil MP-C 18 （5μm, 150 mm×4.6 ram） column with the optimized mobile phase containing 5% （w/v） acetonitrile, 0.01 mol/L L-cysteine and 0.06 moL/L ammonium acetate. The tissues of rats were freeze-dried after giving the medicine for 10 d, and then added into the solution containing 10% （w/v） HC1, 1% （w/v） sulfocarbamide and 0.15% （w/v） KC1 for increasing extraction rate. The resolutions of Hg2＋, MeHg and EtHg were 1.5 and 2.9, respectively. The detection limits of Hg2＋, MeHg and EtHg were 2.0, 1.0 and 0.9 ng/mL, respectively. The relative standard deviation （RSD） of inter- and intra-day precisions ranged from 1.56% to 2.86%. The recovery rates of three different adding level were 87%-101% （n=6）, and the RSDs were smaller than 8.2%. The results show that no MeHg and EtHg were detected in rat tissues. Only soluble mercury （Hg2＋） was determined for the mercury species of SHXW in rat tissues.

Simultaneous Expression of Vitreoscilla Globin Gene and Lytic Genes of Phage A in a Novel Recombinant Escherichia Coli Used for Production of PHB

Exogenous Vitreoscilla globin gene (vgb), lytic genes of phage A with S amber mutation (S-RRz) and poly(B-hydroxybutyrate) (PHB) biosynthetic genes (phbCAB) were cloned into a same Escherichia coli cell, simultaneously or respectively. Six novel strains containing phbCAB and vgb with or without lytic genes were constructed. Strain VG1 (pTU14), in which vgb, phbCAB and S-RRz could all be successfully expressed, has superior characteristics in cell growth and PHB accumulation, while the results of strains containing vgb and phbCAB without S- RRz were not better than that of strains harbored ph&CAB only. The simultaneous expression of vgb and S- RRz in the recombinant VG1 (pTU14) showed a great potential for low-cost production of PHB.

Development and evaluation of a DNA microarray assay for the simultaneous detection of nine harmful algal species in ship ballast and seaport waters

Rapid,high-throughput and reliable methods are urgently required to accurately detect and monitor harmful algae,which are responsible for algal blooms,such as red and green tides. In this study,we successfully developed a multiplex PCR-based DNA microarray method capable of detecting nine harmful algal species simultaneously,namely A lexandrium tamarense,Gyrodinium instriatum,Heterosigma akashiwo,Karenia mikimotoi,Prorocentrum donghaiense,Prorocentrum minimum,Ulva compressa,Ulva ohnoi and Ulva prolifera. This method achieved a limit of detection(LOD) of 0.5 ng of genomic DNA(orders of magnitude of the deci-nanogram range) in the tested algae cultures. Altogether,230 field samples from ship ballast waters and seaport waters were used to evaluate the DNA microarray. The clinical sensitivity and specificity of the DNA microarray assay in detecting field samples were 96.4% and 90.9%,respectively,relative to conventional morphological methods. This indicated that this high-throughput,automatic,and specific method is well suited for the detection of algae in water samples.

A timeslot assignment scheme for cluster-tree based wireless sensor network

Many efforts have been made to develop time division multiple access （TDMA） slots allocation in a multi-hop converge-cast wireless sensor network （WSN）, however, most of them either use complex algorithm or concern frames only without simultaneous transmission in a single slot. In this paper, we present a timeslot assignment scheme for cluster-tree-based TDMA WSN, co：＇ering three frequently used working modes in practical applications. The shortest frame formed can guarantee real-time conununication and is also facilitated for message and slot integration, since timeslots allocated to a single node are continuous. During allocation processes, the algorithms are distributed and light-weighted. The experiment resulted from a WSN prototype system shows that our scheme can achieve a good reliability.

Puff-by-puff Transfer Ratios of Some Added Flavors in Cigarettes

[Objecdve] The aim was to observe the puff-by-puff transfer ratios of some flavors in cigarettes. [Method] Based on national stand- ards, the puff-by-puff transfer of tobacco of carbonyl flavors was analyzed. In the meantime, by dint of simultaneous distillation and extraction equip- ment coupled to GC and GC/MS, the puff-by-puff transfer ratios to TPM of smoke were expounded and compared. [ Result] The puff-by-puff deliv- ery profiles of NFDPT,nicotine and carbon monoxide increased with increasing puff number. This trend was similar to that of particulate matters. The transfer ratio of flavored tobacco was increasing in general, but partial flavors augmented to the maximum value and then decreased slowly. [ Conclusion] The study provided reference for the application of carbonyl compounds in tobacco.

Reducing neighbor discovery latency in docking applications

Neighbor discovery is important for docking applications,where mobile nodes communicate with static nodes situated at various rendezvous points.Among the existing neighbor discovery protocols,the probabilistic methods perform well in average cases but they have aperiodic,unpredictable,and unbounded discovery latency.Yet,deterministic protocols can provide bounded worst-case discovery latency by sacrificing the average-case performance.In this study,we propose a mobility-assisted slot index synchronization(MASS),which is a new synchronization technique that can improve the average-case performance of deterministic neighbor discovery protocols via slot index synchronization without incurring additional energy consumption.Furthermore,we propose an optimized beacon strategy in MASS to mitigate beaconing collisions,which can lead to discovery failures in situations where multiple neighbors are in the vicinity.We evaluate MASS with theoretical analysis and simulations using real traces from a tourist tracking system deployed at the Mogao Grottoes,which is a famous cultural heritage site in China.We show that MASS can reduce the average discovery latency of state-of-the-art deterministic neighbor discovery protocols by up to two orders of magnitude.

Homogenization of climate series:The basis for assessing climate changes

Long-term meteorological observation series are fundamental for reflecting climate changes.However,almost all meteorological stations inevitably undergo relocation or changes in observation instruments,rules,and methods,which can result in systematic biases in the observation series for corresponding periods.Homogenization is a technique for adjusting these biases in order to assess the true trends in the time series.In recent years,homogenization has shifted its focus from the adjustments to climate mean status to the adjustments to information about climate extremes or extreme weather.Using case analyses of ideal and actual climate series,here we demonstrate the basic idea of homogenization,introduce new understanding obtained from recent studies of homogenization of climate series in China,and raise issues for further studies in this field,especially with regards to climate extremes,uncertainty of the statistical adjustments,and biased physical relationships among different climate variables due to adjustments in single variable series.

Time synchronization in communication networks based on the Beidou foundation enhancement system

Communication networks rely on time synchronization information generated by base station equipment(either the Global Navigation Satellite System receiver or rubidium atomic clock) to enable wireless networking and communications. Meanwhile, the time synchronization among base stations depends on the Network Time Protocol. With the development of mobile communication systems, the corresponding time synchronization accuracy has increased as well. In this case, the use of sparsely distributed-high-precision synchronization points to synchronize time for an entire network with high precision is a key problem and is the foundation of the enhanced network communication. The current receiver equipment for China's digital synchronous network typically includes dedicated multi-channel GPS receivers for communication; however, with the development of GPS by the USA, network security has been destabilized and reliability is low. Nonetheless, network time synchronization based on Beidou satellite navigation system timing devices is an inevitable development trend for China's digital communications network with the establishment of the independently developed BDS, especially the implementation and improvement of the Beidou foundation enhancement system.