二维条码技术在数字水印中的应用

将二维条码作为数字水印嵌入到DCT域数字图像中,结合密码技术在二维条码中的应用,使二维条码数字水印在图像传输过程中保密性更强.     

信息识别技术与物流信息化在航空器材管理中的应用

本文介绍了条码识别技术及其在航空器材管理系统中的应用，并把物流信息化引入到航空器材管理。     

条码技术在飞机制造中的应用研究

条码自动识别技术是以计算机、光电技术和通信技术的发展为基础的一项综合科学技术,是信息数据自动识别、输入的重要方法和手段.经过多年的研究与应用,包括条码打印机、扫描器、远程数据采集器、各类耗材在内的条码硬件技术已经日趋成熟.条码是由一组规则排列的条、空及其对应字符组成的识别标记,由条码符号和对应字符（包括数字、字母及特殊或专用字符集等）组成,用以表示一定的信息.     

自动行李处理系统中条码识别子系统的多条码处理技术探讨

本文较详细地介绍了在行李自动处理系统中多条码处理的实现方法、处理过程。同时简要介绍行李自动处理系统中条码识别子系统的组成、工作原理和行李条码的产生。     

二维条码技术及其在产品质量数据管理中的应用

系统阐述了条码技术,重点介绍了二维条码的特点、常用码制、编码技术、识别方法以及与磁卡、IC卡等自动化识别系统的对比,并介绍了二维条码技术在质量数据追踪方面的应用.     

二维条码技术简析

全面阐述二维条码技术,分析二维条码符号的生成技术、识读技术以及制成技术,对二维条码核心技术进行了剖析,最后对二维条码技术的应用进行了总结.     

信息隐藏技术中二维条码的实现

介绍了二维条码符号表示及纠错码生成,给出二维条码用于信息隐藏技术的方法和途径,实现了用 PDF417码传送信息,使通信信息更安全。     

一种基于天水线的红外舰船图像目标识别方法

针对海天背景下红外舰船目标的识别,提出了一种基于天水线的目标识别方法.利用被识别目标相对天水线的空间位置目标红外特征量和图像帧间信息识别目标,在强干扰环境下,利用该方法进行了仿真实验,得到了很好的效果.     

二维条码技术及其在军械装备器材管理中的应用

随着条码技术的发展,二维条码PDF417因其具有数据量大、纠错能力强、信息保密性高等特性,在我国经济建设和国防建设的诸多领域将有广阔的应用前景.     

在制品管理中条码技术的应用

针对面向订单的单件、小批量生产制造企业,设计了一套条码数据采集系统,分析了主要运作流程和功能模块.在在制品的管理中提出了基于不同级别的工件生产状态定义,并给出了相应的加工、检验判定准则.经实际使用证明条码技术运用于工业现场是可行的.     

Joint TNT and RDX detection via quadrupole resonance

Quadrupole resonance (QR) technology has been receiving increasing attention for explosive detection in applications including landmine detection. It can be used as a confirming sensor for buried plastic landmine detection by detecting the explosives within the mine. Since a single mine can contain more than one type of explosives (e.g., trinitrotoluene (TNT) and (RDX) compound), a detector designed to detect only one type of explosive may not provide the best detection. We focus herein on the joint detection of TNT and RDX explosives for the landmine detection via the QR sensor. To mitigate the RF interferences (RFIs) associated with the QR measurements, we apply a doubly constrained robust Capon beamformer (DCRCB) to perform the spatial beamforming by exploiting the spatial correlation of the RFIs. Based on the output of the spatial DCRCB, we devise a generalized likelihood ratio test (GLRT) for the joint TNT/RDX detection, which is referred to as the DCRCB-GLRT detector. We show that our detector has the constant false alarm rate (CFAR) property and that the detection variable obeys a x² -mixture distribution in the mine-free scenario. The effectiveness of the proposed DCRCB-GLRT detector is demonstrated with the experimental data collected by Quantum Magnetics, Inc.     

低轨卫星可控式冗余分包遥测技术

随着卫星功能日趋复杂,遥测参数越来越多,处理要求越来越快,遥测设计面临越来越大的压力,必须拓展新的设计思路.本文讨论了一种低轨卫星可控式冗余分包遥测技术,更好地缓解遥测信道“瓶颈”,满足用户多样化的遥测需求,提高卫星遥测能力.该设计采用PCM（Pulse Code Modulation,脉冲编码调制）遥测和分包遥测相结合的方案,在信道资源有限,遥测参数庞大、用户需求多样的约束条件下,通过星载软件模式控制的方法实现了动态可编程遥测处理和遥测数传通道的冗余处理,提高了遥测信道的资源利用率、遥测设计的灵活性和系统的可靠性,该技术已成功应用于某在轨卫星,并被多颗在研卫星所采用.     

末制导DBS图像匹配方法研究

提出了一种适于工程应用的末制导DBS图像匹配方法,采用DBS成像,结合目标场景中强散射点的空间位置关系实现基于模板的目标场景匹配,快速定位及打击目标,较好地解决了末制导成像识别及定位问题。实测数据仿真结果表明,基于模板的DBS图像匹配算法可抑制多种图像畸变,具有较高的匹配可靠性和匹配精度,满足了雷达导引头DBS图像识别的工程使用要求,具有较强的实用价值。     

Ultra-high performance, low-power, data parallel radar implementations

Radar involves similar operations applied to large amounts of data. It is thus well suited to data parallel (SEMD) hardware. In the past, large data-parallel machines have been applied to radar with limited success. This has been due to such reasons as programming issues, cost, and the hardware being too big for most embedded applications. Most SBVED machines went away a decade ago. There is now a new generation of SIMD COTS technology with powerful processing elements (PEs) and floating-point hardware. WorldScape is applying these chips to radar processing, and has demonstrated significantly more performance with much lower power dissipation (GFLOPS/Watt). These implementations provide attractive alternatives to traditional FPGA and DSP solutions. Lockheed-Martin has provided benchmark validation testing and support for these implementations. The current implementation is based on a 64 PE, 25 GFLOP CS-301 chip supplied by ClearSpeed Technology PLC. WorldScape has demonstrated FFT, Pulse Compression, a form of QR factorization, and other applications on this generation of hardware using a mix of C-level programming and optimized assembly. The next generation chip is compatible, but also has several improvements that will significantly enhance I/O performance as well as raw GFLOP throughput. An updated demonstration and discussion of a scalable processing platform for embedded radar processing which significantly improves I/O performance and provides a roadmap to government-qualified hardware for technology insertion. Architectures, data parallel coding approaches, additional functionality of the scalable processing platform, and relevance to embedded defense radar applications will be discussed.     

基于LAS码的星群多目标测控技术研究

针对星群多目标同时测控问题,基于星群轨道根数的时延特性和多普勒频移特性分析可得,星群多目标测控的上行链路遥控与测距信号可实现S CDMA（Synchronous Code Division Multiple Access,同步码分多址）,由于星间距离较小,下行链路遥测与测距信号满足QS CDMA（Quasi synchronous code division multiple access,准同步码分多址）.上行链路遥控和测距信号形式设计为PCM BPSK CDMA（Pulse Code Modulation Binary Phase Shift Keying Code Division Multiple Access,脉冲编码调制二进制相移键控码分多址）,上行链路信号采用Gold序列扩频;下行链路遥测和测距信号形式设计为PCM BPSK CDMA,根据总的时延差,提出下行链路采用基于等长脉冲间隔法构造的LAS（Large Area Synchronous,大区域同步）码扩频.结果表明：比特信噪比Eb/N0为10.5 dB时,遥控误码率为1＆#215;10 6;Eb/N0为9.6 dB时,遥测误码率为1×10^5——与达到相同误码性能的Gold序列相比有1 dB改善,因此,LAS码相比于Gold码能够获得更好的误码性能.     

Atomic Power Engineering under Falsified Safety Standards

In July 1970 the United States Department of Justice accused the American Society of Mechanical Engineers (ASME) of violating the Sherman Antitrust Act and of acting in restraint of trade by restricting the ASME Certificate of Authorization and the use of the Code Symbol Stamps to boilers and pressure vessels manufactured in the United States and Canada. During the succeeding two years attorneys for the parties in the case formulated a Consent Decree without a public confrontation in the Court. Furthermore, the membership of ASME was kept uninformed until October of 1972, after the Consent and Final Judgment had become effective and new procedures had been developed for allowing foreign manufacturers to apply the ASME Code Symbol Stamps to their products. As a consequence, a breakdown in engineered safety standards has been sanctioned and this is undermining the engineering profession's overriding responsibility to protect the public health and safety. This breakdown of professional responsibility is especially serious in the new technology of atomic power. American insurance companies, which have traditionally written 100% insurance coverage for property damage and third party liability against explosions of high pressure steam boilers bearing the ASME Code Stamp, have refused to write such insurance coverage on nuclear reactors. In the author's opinion there is evidence that the Consent was formulated under collusive proceedings and he calls on the members and the Council of ASME to appeal for dismissal of the Consent Decree.     

Lovász条件下LLL算法最简复Givens矩阵形式的研究

为了解决复数域下基于QR分解的LLL（A．K．Lenstra,H．W．Lenstraand L．Lovasz）算法中复Gives旋转矩形式不统一的问题,文章从复数域下原始LLL算法中Gram—Schmidt系数与QR分解的上三角矩阵胄中元素之间的关系出发,证明了上三角矩阵R的元素与Gram—Schmidt系数以及Lovasz条件之间的等价的关系;从复数的指数形式出发,推导出2种适合LLL算法的复Givens旋转矩阵形式,并证明只有其中一种符合Lovasz条件下复Givens旋转矩阵形式。仿真结果表明,采用基于QR分解的复数域LLL算法的MIMO系统相比采用基于Gram—Schmidt正交化LLL算法的MIMO系统具有更好的误比特率性能。     

State-of-the-art in speaker recognition

Recent advances in speech technologies have produced new tools that can be used to improve the performance and flexibility of speaker recognition. While there are few degrees of freedom or alternative methods when using fingerprint or iris identification techniques, speech offers much more flexibility and different levels to perform recognition: the system can force the user to speak in a particular manner, different for each attempt to enter. Also, with voice input, the system has other degrees of freedom, such as the use of knowledge/codes that only the user knows, or dialectical/semantical traits that are difficult to forge. This paper offers an overview of the state-of-the-art in speaker recognition, with special emphasis on the pros and cons, and the current research lines. The current research lines include improved classification systems, and the use of high level information by means of probabilistic grammars. In conclusion, speaker recognition is far away from being a technology where all the possibilities have already been explored.     

Safety testing of lithium ion batteries for navy devices

Lithium ion battery technology is being introduced into power supplies used by our armed forces for a variety of applications. In many cases, the same cells and design parameters that support commercial battery packs are being used in military battery packs. This approach is expected to result in a major decrease in the total life cycle cost of the equipment these batteries support. On June 13, 1991, NAVSEA issued INST9310.1B1, which states that all lithium battery powered equipment must undergo safety evaluation and approval prior to fleet use. This safety program governs a process whereby approvals are issued for lithium batteries to be used in specific equipment on ground facilities, surface combatants, air combatants, and/or submarines. The Naval Ordnance Safety and Security Activity (NOSSA) manages the program. The chief technical advisors are Code 644 at NSWC Carderock Division and Code 609A at NSWC Crane Division. This paper describes three battery designs that incorporate lithium ion technology, and the results of battery safety tests conducted in accordance with navy requirements.     

双转子系统临界转速的有限元分析

利用有限元软件ANSYS建立简易双转子系统的有限元模型,分别用QR阻尼法和同步响应法计算该双转子系统的临界转速以及主振型。用该软件自带的参数化设计语言（APDL）编制该双转子系统临界转速和不平衡响应的计算程序,分别求出内转子和外转子为主激励的临界转速及主振型。对比结果发现采用QR阻尼法和同步响应法计算双转子系统前三阶临界转速的误差均在1％以内,结果吻合很好。用这2种方法计算双转子系统的临界转速都能得到满足工程精度要求的结果。