Decoding Technique of Concatenated HadamardCodes and Its Performance

The decoding technique of concatenated Hadamard codes and its performance are studied. Efficient soft in soft out decoding algorithms based on the fast Hadamard transform are developed. Performance required by CDMA mobile or PCS speech services, e.g. , BER=10 -3 , can be achieved at Eb/No =0.9 dB using short interleaving length of 192 bits.

Modelling of the behavior of marine oil spills: applications based on random walk techniques

A numerical model has been developed to simulate the transport and fate of oil spilled at sea. The model combines the transport and fate processes of spilled oil with the random walk technique. Oil movement under the influence of tidal currents, wind driven currents, and turbulent eddies is simulated by the PLUME RW dispersion model developed by HR Wallingford. The weathering processes in the model represent physical and chemical changes of soil slicks with time, and comprise mechanical spreading, dispersion, evaporation and emulsification. Shoreline stranding is determined approximately using a capacity method for different shoreline types. This paper presents details of the model, and describe the results of various sensitivity tests. The model is suitable for oil spill contingency planning.

Maximum two-dimensional (u×v,4,1,3)-OOCs

Let Ф（u ×v, k, Aa, Ac） be the largest possible number of codewords among all two- dimensional （u ×v, k, λa, λc） optical orthogonal codes. A 2-D （u× v, k, λa, λ）-OOC with Ф（u× v, k, λa, λc） codewords is said to be maximum. In this paper, the number of codewords of a maximum 2-D （u × v, 4, 1, 3）-OOC has been determined.

UPLINK PERFORMANCE OF CWP-MC-CDMA WITH SPACE DIVERSITY COMBINING TECHNIQUE OVER RAYLEIGH FADING CHANNEL

In this paper, a Complex Wavelet Packet （CWP-MC-CDMA） system uplink model is proposed, based Multi-Carrier Code Division Multiple Access based on the analysis of the principle of MC-CDMA and the use of the optimized complex wavelet packet. Considering that the base station can adopt multiple re- ceiver antennas in the uplink, we employ the Space Diversity Combining （SDC） technique to improve the sys- tem pertbrmance via multiple antennas. The uplink performance of proposed CWP-MC-CDMA system with SDC technique is investigated over Rayleigh lading channel, and corresponding bit error rate analysis is given in detail. The system can avoid the decrease of spectrum efficiency of conventional MC-CDMA due to inserting cyclic prefix. Theoretical analysis and simulation result show that the application of SDC technique can improve the CWP-MC-CDMA system ability to combat spatial lading and various interferences effectively. Moreover, the proposed system based on SDC technique has superior Bit Error Rate （BER） performance over the Discrete Fourier Transform （DFT） and SDC based MC-CDMA system and the real wavelet packet and SDC based MC-CDMA system.

The Adaptive Long-Distance HF Broadcasting System Based on Backscatter Technique

We put forth a project, that is: using the backscatter technique to realize adaptive long-distance HF broadcasting system in order to improve the quality of HF broadcasting. Then, we analyze errors of the system due to the deviation of the ionospheric parameters' prediction. From the analysis, we draw the conclusion that our project is feasible. In addition, we point out that we can use frequency-spreading and information-coding technique to acquire more clear ionograms. We also offer a judgment on how to choose the control propagation mode on condition of multihop and the existence of more than one propagation mode on the signals' path.

LDAP Injection Techniques

The increase in the number of databases accessed only by some applications has made code injection attacks an important threat to almost any current system. If one of these applications accepts inputs from a client and executes these inputs without first validating them, the attackers are free to execute their own queries and therefore, to extract, modify or delete the content of the database associated to the application. In this paper a deep analysis of the LDAP injection techniques is presented. Furthermore, a clear distinction between classic and blind injection techniques is made.

Multiplexing Technique Applied in the Optically Powered Oil-tank Detection System

The method of using multiplexing technique to realize the optically powered multiple detection system is presented. As this system adopted novel time and pulse width multiplexing techniques, reliable separation and error code correcting techniques, it realizes optically powered multiple channel and parameters detection, and successfully applied in the oil tanks for temperature, pressure, liquid level and reserve measurings.

Static response of functionally graded multilayered two-dimensional quasicrystal plates with mixed boundary conditions

The unusual properties of quasicrystals(QCs)have attracted tremendous attention from researchers.In this paper,a semi-analytical solution is presented for the static response of a functionally graded(FG)multilayered two-dimensional(2 D)decagonal QC rectangular plate with mixed boundary conditions.Based on the elastic theory of FG 2 D QCs,the state-space method is used to derive the state equations composed of partial differential along the thickness direction.Besides,the Fourier series expansion and the differential quadrature technique are utilized to simulate the simply supported boundary conditions and the mixed boundary conditions,respectively.Then,the propagator matrix which connects the field variables at the upper interface to those at the lower interface of any homogeneous layer can be derived based on the state equations.Combined with the interface continuity condition,the static response can be obtained by imposing the sinusoidal load on the top surfaces of laminates.Finally,the numerical examples are presented to verify the effectiveness of this method,and the results are very useful for the design and understanding of the characterization of FG QC materials in their applications to multilayered systems.

Arc-length technique for nonlinear finite element analysis

Nonlinear solution of reinforced concrete structures, particularly complete load-deflection response, requires tracing of the equilibrium path and proper treatment of the limit and bifurcation points. In this regard, ordinary solution techniques lead to instability near the limit points and also have problems in case of snap-through and snap-back. Thus they fail to predict the complete load-displacement response. The arc-length method serves the purpose well in principle, received wide acceptance in finite element analysis, and has been used extensively. However modifications to the basic idea are vital to meet the particular needs of the analysis. This paper reviews some of the recent developments of the method in the last two decades, with particular emphasis on nonlinear finite element analysis of reinforced concrete structures.

Multiple bit upsets mitigation in memory by using improved hamming codes and parity codes

This paper combines improved Hamming codes and parity codes to assure the reliability of memory in presence of multiple bit upsets with low cost overhead.The redundancy bits of improved Hamming codes will be appended at the end of data bits,which eliminates the overhead of interspersing the redundancy bits at the encoder and decoder.The reliability of memory is further enhanced by the layout architecture of redundancy bits and data bits.The proposed scheme has been implemented in Verilog and synthesized using the Synopsys tools.The results reveal that the proposed method has about 19% less area penalties and 13% less power consumption comparing with the current two-dimensional error codes,and its latency of encoder and decoder is 63% less than that of Hamming codes.

Performance of MIMO Systems Using Space Time Block Codes (STBC)

Digital Communications, in relation to wireless networks, have taken off in recent years due to the expanding need to communicate faster and more efficiently. A popular way to achieve this is by using wireless Multiple Input Multiple Output (MIMO) communication systems. MIMO systems utilize Space Time Block Codes (STBC) as one of the leading ways to obtain higher data rates with limited bandwidth and power. With several STBC methods currently available, this paper analyzes simulations using Orthogonal Space Time Block Codes (OSTBC) in Rayleigh fading channels to evaluate the performance of MIMO systems. The selection to use a Rayleigh fading channel as a model for a non-line-of-sight (nLOS) environment is selected to mimic installations where a large number of signal paths and reflections are expected. All simulations are coded, generated and plotted using MATLAB resulting in graphical data representing the bit-error rate (BER) to signal-to-noise ratio (Eb/N0) or SNR. Each simulation captures how different configurations of key variables including code rate, diversity and antenna count can impact system performance. Four modulation schemes (BPSK, QPSK, 16-QAM and 64-QAM) are included in each simulation. Conclusive evidence based upon these simulations suggests higher diversity gains were achieved with a greater number of antennas. The most significant factor for increasing system performance was using a lower count of transmit antennas with a higher count of receive antennas.

Totally Coded Algorithm for Switched-Current Network Analysis in Frequency Domain

Based on mirror-blocks, a totally coded algorithm （TCA） for switched-current （SI） network analysis in frequency domain is presented. The algorithm is simple, available, and suitable for any swltched-current networks. A basis of analysis and design for switched-current networks via this algorithm is provided.

Emergence of Plastidial Intergenic Spacers as Suitable DNA Barcodes for Arid Medicinal Plant <i>Rhazya stricta</i>

The desert plant Rhazya stricta has anticancer and antimicrobial properties, and is widely used in indigenous medicines of Saudi Arabia. However, the therapeutic benefits rely on an accurate identification of this species. The authenticity of R. stricta and other medicinal plants and herbs procured from local markets can be questionable due to a lack of clear phenotypic traits. DNA barcoding is an emerging technology for rapid and accurate species identification. In this study, six candidate chloroplastid barcodes were investigated for the authentication of R. stricta. We compared the DNA sequences from fifty locally collected and five market samples of R. stricta with database sequences of R. stricta and seven closely related species. We found that the coding regions matK, rbcL, rpoB, and rpoC1 were highly similar among the taxa. By contrast, the intergenic spacers psbK-psbI and atpF-atpH were variable loci distinct for the medicinal plant R. stricta. psbK-psbI clearly discriminated R. stricta samples as an efficient single locus marker, whereas a two-locus marker combination comprising psbK-psbI + atpF-atpH was also promising according to results from the Basic Local Alignment Search Tool and a maximum likelihood gene tree generated using PHyML. Two-dimensional DNA barcodes (i.e., QR codes) for the psbK-psbI and psbK-psbI + atpF-atpH regions were created for the validation of fresh or dried R. stricta samples.

Research on Recognition Technology of 2-Dimensional Barcode

This paper briefly introduces the characteristics and structure of symbol QR two-dimensional code, a detailed analysis of the image processing method to identify QR code of the whole process, and the bilinear mapping method is applied to image correction, the final steps of decoding are given. The actual test results show that, the design algorithm has theoretical and practical, this recognition system can correctly read QR code, and has high recognition rate and recognition speed, has practical value and application prospect.

Improving the Angular Resolution of Coded-Mask Telescopes by Direct Demodulation

We develop a new procedure to improve the angular resolution of coded-mask telescopes by the Direct Demodulation Method （DDM）. DDM has been applied to both real and simulated data of INTEGRAL/IBIS. The angular resolution of IBIS/ISGRI has been improved from about 13＇ to 2＇.

论中国传统法典立法技术的发展——以唐明律计亩论罪为中心的考察

中国传统立法沿革表明,其法典立法技术在不断进步,而唐明律计亩论罪量刑方式则较为明显地反映出这种变化。其立法技术沿革模式可以分为两类:一类是侵犯他人田土使用权和所有权的犯罪,罪刑虽然有所改动、整合,但传承关系明显;另一类与土地分配、赋役征派等基本国策相关联,因政策调整,犯罪类型差异大,但其部分刑等设计却随刑罚体系传承下来。计亩论罪与计赃论罪的原理不同,不能简单视为实物计赃,其行用与犯罪不符合盗罪构成有关,也是国家财政方针在法律中的如实反映。唐明两朝计亩论罪呈现出量刑从公私不分到区分官民、刑罚偏轻且具备体系性的鲜明特点。与唐代相较,明代更加重视官有财产保护以及体系内各罪刑罚间的联系,其立法技术更趋完善。

教育法典立法目的条款的规范构造

基于教育法典的基础性地位、体系化目标以及教育立法传统,设置教育法典立法目的条款具有必要性。该条款的构造,分为实质和形式两部分。构造实质内容时,应从个人、社会、国家三个层面出发,分别考虑人民大众的利益诉求、社会发展的现实需要以及党和国家的方针政策,从而确定立法目的条款的内在价值体系。构造形式内容时,应以“为了+机能目的(价值目的)+制定本法”为规范结构,在价值目的的指引下,首先通过提取公因式的方式从现有教育法律法规中提炼机能目的,然后从中确立符合内在价值体系的机能目的,最后按照价值位阶和形式逻辑规则确定各目的间的排序。如此,方可构造出内容正确、形式合理,能够促成法典体系化的立法目的条款。

教育法典编纂的“公因式元素”及其逻辑主线

编纂契合新时代需求的教育法典,需要运用提取公因式的立法技术。运用该技术提取“公因式元素”,契合法典总分模式的体例要求,符合司法裁判的规范适用要求,得到国内外法典编纂的有效验证,符合中国教育国情的实际需求。教育法典提取“公因式元素”的过程分为三步:首先确定提取范围,其次通过因式分解法以相似性确定提取类别,最后通过逻辑涵摄方法以共有性提取特定“公因式元素”。教育法基本原则具有天然“公因式元素”属性;以法律效果和构成要件为双重标准,可进一步提取其他“公因式元素”,大致包含受教育权、教育主体、教育客体、教育内容等。基于逆向逻辑检视,可以洞察教育法典的各“公因式元素”之间存在一条以“权力-权利”为核心紧密联结的逻辑主线,其以保障受教育权为逻辑起点,保障教育主体权利、规范教育活动和呈现合理教育内容为联结中介,以国家教育权为外部保障,最终指向人的全面发展这一终极目标。

Quantitative Comparative Study of the Performance of Lossless Compression Methods Based on a Text Data Model

Data compression plays a key role in optimizing the use of memory storage space and also reducing latency in data transmission. In this paper, we are interested in lossless compression techniques because their performance is exploited with lossy compression techniques for images and videos generally using a mixed approach. To achieve our intended objective, which is to study the performance of lossless compression methods, we first carried out a literature review, a summary of which enabled us to select the most relevant, namely the following: arithmetic coding, LZW, Tunstall’s algorithm, RLE, BWT, Huffman coding and Shannon-Fano. Secondly, we designed a purposive text dataset with a repeating pattern in order to test the behavior and effectiveness of the selected compression techniques. Thirdly, we designed the compression algorithms and developed the programs (scripts) in Matlab in order to test their performance. Finally, following the tests conducted on relevant data that we constructed according to a deliberate model, the results show that these methods presented in order of performance are very satisfactory:- LZW- Arithmetic coding- Tunstall algorithm- BWT + RLELikewise, it appears that on the one hand, the performance of certain techniques relative to others is strongly linked to the sequencing and/or recurrence of symbols that make up the message, and on the other hand, to the cumulative time of encoding and decoding.

环境法典编纂中“提取公因式”立法技术适用性及限度

在“总分结构”的结果导向下,提取公因式立法技术迎合了改善当前环境法自身体系性问题以及“适度化”环境法典的体系格局的迫切期待,从而形成了价值上的迷思。提取公因式作为从数学中援引的方法,必然受制于其数学逻辑,并继承其局限性。提取公因式的功能本质是恒等变形,作为技术结果的公因式具有既定的正当性、天然的固定性、客观的独立性,无益于环境法典这一法律改革的目的。法律通过语句来表达规范意义,这决定了提取公因式的应用离不开对法律文本的分析。具有任意性、线性等特征的环境法律文本区别于具有独立意义的数理符号,同时环境法律文本中不完整法条、代词的使用以及非语言因素等语境也无法被纳入因式集合作为拟提取公因式的对象。通过分析这一技术的合目的性,最终得出提取公因式立法技术无法满足环境法典编纂的目的和价值需要。