潜艇快速性模型试验分析及实艇预报新方法研究

本文在研究二向度实效伴流理论的基础上,建立了新的潜艇快速性模型试验分析方法,将该方法系统地应用于各类潜艇快速性模型试验分析,结果表明它适用于所有单轴潜艇快速性模型试验分析,特别是尾部有较强旋转流动的情形;本文还基于二向度方法,并引入摩擦形状因子的概念,提出了新的潜艇快速性预报方法,结果表明,新方法的最终预报结果与传统方法相同,但推进效率的分量不同。

远洋鱿鱼钓船阻力图谱研究

在船型概念设计阶段,基于船舶阻力图谱进行船舶快速性分析是一种高效便捷的方式.由于远洋鱿鱼钓船船型方案设计缺少专用船舶阻力图谱,研究了适用于远洋鱿鱼钓船的阻力图谱开发方法、步骤和基于图谱的航速预报.以66 m远洋鱿鱼钓船为母型船,基于宽度和吃水比将变换船型分成两大系列,再根据排水体积长度比,将每个大系列进一步细化成3个小系列作为目标船型进行研究,建立了母型船三维模型及其系列派生船型.基于Star-CCM+软件的重叠网格方法,对系列船型阻力进行数值模拟,将阻力计算结果通过二因次法换算为15℃海水下实船阻力及对应有效功率系数,绘制远洋鱿鱼钓船阻力图谱.利用该图谱估算母型船阻力并与船模试验结果进行对比,证明了远洋鱿鱼钓船阻力图谱具有较高精度,可用于远洋鱿鱼钓船概念设计和方案优化设计.

Soluble Expression and Rapid Quantification of GFP-hepA Fusion Protein in Recombinant Escherichia coli

To establish a rapid quantification method for heparinase I during its production in recombinant Escherichia coli, a translational fusion vector was constructed by fusing the N terminus of heparinase I to the C terminus of a green fluorescent protein mutant （GFPmutl）. As a result, not only was the functional recombinant expression of heparinase I in E. coli accomplished, but also a linear correlation was obtained between the GFP fluorescence intensity and heparinase I activity, allowing enzyme activity to be quantified rapidly during the fermentation.

Effects of rapid solidification process and 0.1%Pr/Nd addition on characteristics of Sn-9Zn solder alloy and interfacial properties of Cu/solder/Cu joints

Rapidly solidified Sn-9Zn-0.1Pr(/Nd) alloy foils were prepared by melt-spinning method. Through comparison, the effects of rapid solidification process and 0.1%Pr/Nd(mass fraction) addition on the microstructure, thermodynamic characteristic of Sn-9Zn solder alloy were analyzed. The tensile-shear tests were used to evaluate the mechanical properties of solder/Cu joints. The results show that the rapid solidification process can greatly refine the microstructure of Sn-9Zn-0.1Pr(/Nd) alloys. After rapid solidification, the effects of Pr/Nd addition on microstructure are depressed. The pasty range of the rapidly solidified Sn-Zn-RE solders is also reduced significantly. The mechanical properties of solder/Cu joints are obviously improved using the rapidly solidified Sn-9Zn-0.1Pr(/Nd) solder alloy, which results in the formation of uniform interface. The promotion effect of Nd addition in Sn-9Zn alloy on the interfacial reaction of solder/Cu joint is more remarkable than that of Pr.

Quality of Service Improvement for High-Speed Railway Communications

With the fast development of highspeed railways,a call for fulfilling the notion of communication at "anytime,anywhere" for high-speed train passengers in the Train Operating Control System is on the way.In order to make a realization of that,new railway wireless communication networks are needed.The most promising one is the Long Term Evolution for Railway which will provide broadband access,fast handover,and reliable communication for high mobility users.However,with the increase of speed,the system is subjected to high bit error rate,Doppler frequency shift and handover failure just like other system does.This paper is trying to solve these problems by employing MIMO technique.Specifically,the goal is to provide higher data rate,higher reliability,less delay,and other relative quality of services for passengers.MIMO performance analysis,resource allocation,and access control for handover and various services in a two-hop model are proposed in this paper.Analytical results and simulation results show that the proposed model and schemes perform well in improving the system performances.

Isolation and rapid genetic characterization of a novel T4-like bacteriophage

Ubiquitous on earth,bacteriophages are the most abundant entities in every ecosystem,but human knowledge about them is still limited compared with that about other forms of organisms.To enrich human knowledge and promote the utilization of bacteriophages,it is necessary to isolate and characterize as many as possible different bacteriophages.Here we describe the isolation of a T4-like bacteriophage IME08 and a rapid method for its genetic characterization.With this method we easily cloned a few random fragments of the bacteriophage genome.Sequence analysis of these random clones showed that bacteriophage IME08 shared the highest sequence similarity with T4-like Enterobacteria phage T4（94%identity）,JS98（95% identity）,JS10（95%identity） and RB14（94%identity） respectively,which suggested that IME08 belonged to T4-like bacteriophage genus.

A way finding r（k,I） and r（3,10）=41

On basis of two definitions that 1. an induced subgraph by a vertex vi E G and its neighbors in G is defined a vertex adjacent closed subgraph denoted by Qi （=G[V（Nvi）]）, with the vertex vi called the hub; 2. A r（k,1）-1 vertices connected graph is called a （k,l）-Ramsey graph denoted by RG（k,l）,if and only if 1. RG（k,l） contains only cliques of degree k-1, and its complement contains only cliques of degree l-l; 2. the intersect Qi∩Qj of any two nonadjacent vertices vi and vj of RG（k,1） contains Kk.2, and the intersect Qi∩Qj of any two nonadjacent vertices vi and vj of its complement RG（l,k） contains KI.2. Two theorems that theoreml ： the biggest clique in G is contained in some Qi of G, and theorem2： r（k,l）= [ V（RG（k,I）） I ＋1 are put forward and proved in this paper. With those definitions and theorems as well as analysis of property of chords a method for quick inspection and building RG（k,I） is proposed. Accordingly, RG（10,3） and its complement are built, which are respectively the strongly 29-regular graph and the strongly 10-regular graph on orders 40. We have tested RG（10,3） and its complement RG（3,10）,and gotten r（3,10）=41.

A Way Finding the Classical Ramsey Number and r（4,6）=36

Two definitions are given that Definitionl： an induced subgraph by a vertex vie G and its neighbors in G is defined as a vertex adjacent closed subgraph, and denoted by Qi （=G[V（Nvi）]）, with the vertex vi called the hub; and Definition2： A r（k,I）-I vertices graph is called the （k,l）-Ramsey graph, denoted by RG（k,1）, if RG（k,1） only contains cliques Kk.1 and the intersect QiNQj of any two nonadjacent vertices vi and vj of RG（k,I） contains only Kk-2. Meanwhile, the RG（k,l）＇s complement RG（I,k） contains only cliques Kl.l, and the intersect QiNQj of any two nonadjacent vertices vi and vj of RG（I,k） contains only Ki.2. On the basis of those definitions, two theorems are put forward and proved in this paper. They are Theoreml： the biggest clique in G is contained in some Qi of G, and Theorem 2： r（k,1） = [V（RG（k,I））I ＋ 1. With those definitions and theorems as well as analysis of chord property, a method for quick inspection and building RG（k,1） is proposed. Accordingly, RG（4,6） is built, it is a strongly 14-regular graph on order 35. We have tested RG（4,6） and its complement, as a result, they meet the defintion2, so we proclaim that r（4,6）=36.

Robust Digital Audio Watermarking Scheme Using Blind Source Separation with Global Optimal Property

The paper proposes a robust digital audio watermarking scheme using blind source separation(BSS) based on the global optimization of independency metric(IM),which is formulated as a generalized eigenvalue(GE) problem.Compared with traditional information-theoretical approaches used in digital audio watermarking,such as fast independent component analysis(FastICA),the proposed scheme has lower complexity without timeconsuming iteration steps used in FastICA.To make full use of the multiresolution characteristic of discrete wavelet transform(DWT) and the energy compression characteristic of discrete cosine transform(DCT),the watermark is embedded in the middle DWT-DCT coefficients and the independent component analysis(ICA) approach based on IM is used in the detecting scheme.Simulation results based on Stirmark for Audio v02 show that the proposed scheme has strong robustness as well as the imperceptibility and security.