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51.
Luke B. L. Pace P. E. 《IEEE transactions on information theory / Professional Technical Group on Information Theory》2007,53(5):1759-1766
The robust symmetrical number system (RSNS) is a modular system formed using Nges2 integer sequences and ensures that two successive RSNS vectors (paired terms from all N sequences) differ by only one integer. This integer Gray-code property reduces the possibility of encoding errors and makes the RSNS useful in applications such as folding analog-to-digital converters (ADCs), direction finding antenna architectures, and photonic processors. This paper determines the length of combined sequences that contain no vector ambiguities. This length or longest run of distinct vectors we call the RSNS dynamic range (Mcirc). The position of Mcirc which is the starting point in the sequence is also derived. Computing Mcirc and the position of Mcirc allows the integer Gray-code properties of the RSNS to be used in practical applications. We first extend our two-sequence results to develop a closed-form expression for Mcirc for a three-sequence RSNS with moduli of the form 2r-1,2r,2r+1. We then extend the results to solving the N-sequence RSNS ambiguity locations in general 相似文献
52.
Brett Jack Fontana Raymond P. Walsh Peter J. Thouret Wolfgang E. Gerber Max Kaufman Rudolph Thorington Luke 《Industry Applications, IEEE Transactions on》1981,(2):210-216
The design considerations for filaments in energy conserving incandescent lamps are described. Such lamps require compact high emissivity filaments to absorb infrared radiation reflected from heat mirrored focusing envelopes. The relationships between the electrical parameters in the radiation returning environment and in the clear surroundings are developed. Efficiency experiments with filaments of various geometries under conditions of radiation return were performed. A highly compact coiled coil filament seems most promising for development. A calculation is presented of the filament emissivity as a function of spacing of the windings in a coil. Measurements of the emissivity as a function of the pitch of a coiled coil filament agree with the calculation. 相似文献
53.
The origins of the sampling theorem 总被引:1,自引:0,他引:1
The publications of Claude E. Shannon brought the sampling theorem to the broad attention of communication engineers. This article demonstrates how practicians, theoreticians, and mathematicians discovered the implications of the sampling theorem almost independent of one another 相似文献
54.
Luke RobertsAuthor Vitae Robert LinesAuthor VitaeSub ReddyAuthor Vitae John HayAuthor Vitae 《Sensors and actuators. B, Chemical》2011,152(1):63-67
A triggered oxygen indicator, formulated from a combination of electrochrome, titanium dioxide and EDTA, was evaluated for use in modified atmosphere packaging. Methylene blue was not an ideal electrochrome due to its slow reduction to the leuco form and fast subsequent oxidation by oxygen present at low concentrations, >0.1%. Polyviologen electrochromes showed much faster reduction after exposure to UV light. Thionine and 2,2′-dicyano-1,1′-dimethylviologen dimesylate, which have more anodic reduction potentials compared to methylene blue, can be used to produce oxygen indicators with decreased sensitivity to oxygen. These indicators can be used to detect oxygen even when levels increase up to 4.0%. 相似文献
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57.
Shanju Zhang Lingbo Zhu Marilyn L. Minus Han Gi Chae Sudhakar Jagannathan Ching-Ping Wong Janusz Kowalik Luke B. Roberson Satish Kumar 《Journal of Materials Science》2008,43(13):4356-4362
We report continuous carbon nanotube (CNT) fibers and yarns dry-drawn directly from water-assisted chemical vapor deposition
(CVD) grown forests with about 1-mm height. As-drawn CNT fibers exist as aerogel and can be transformed into more compact
fibers through twisting or densification with a volatile organic liquid. CNT fibers are characterized by scanning electron
microscopy, X-ray photoelectron spectroscopy, Raman microscopy, and wide-angle X-ray diffraction. Mechanical properties and
electrical conductivity of the post-treated CNT fibers are investigated. The resulting fibers show the work of rupture of
30 J/g and DC electrical conductivity of 5.0 × 104 S/m. 相似文献
58.
北京智化寺藏殿建筑梁架、斗栱、彩画、雕饰与造像完整,是一处难得的完整保留了明代空间特色的建筑遗存。本文以智化寺藏殿及其经藏为主要研究对象,首先通过文字史料与遗迹现象互证,廓清智化寺营造史与藏殿形制中的两大“反常”之处:“快速建造”与“不能转的转轮经藏”,并指出后者可能为明正统年间的新创形式。其次,通过对相关图像与实物的比较及对历史环境的分析,探讨新形式可能的来源。最后,尝试重建明正统年间智化寺藏殿的空间意象,并解析这些意象背后的四种突破“常规”的形式操作方法:一,功能的集约化;二,意义的整合与渗透; 三,空间的轴线、比例与分层;四,装饰表皮与结构骨架分离。通过对营造意图与操作方法的双重解读,得以更加深入地认识古代营造者面对特定问题时展现的设计智慧。 相似文献
59.
Back Cover: Lipopeptide Nanoparticles: Development of Vaccines against Hookworm Parasite (ChemMedChem 10/2015) 下载免费PDF全文
60.
Discovery of Quinoline‐Derived Trifluoromethyl Alcohols,Determination of Their in vivo Toxicity and Anticancer Activity in a Zebrafish Embryo Model 下载免费PDF全文
Prof. Dr. Vinoth Sittaramane Jihan Padgett Philip Salter Ashley Williams Shauntelle Luke Rebecca McCall Prof. Dr. Jonathan F. Arambula Vincent B. Graves Mark Blocker David Van Leuven Keturah Bowe Julia Heimberger Hannah C. Cade Supriya Immaneni Prof. Dr. Abid Shaikh 《ChemMedChem》2015,10(11):1802-1807
In this study the rational design, synthesis, and anticancer activity of quinoline‐derived trifluoromethyl alcohols were evaluated. Members of this novel class of trifluoromethyl alcohols were identified as potent growth inhibitors in a zebrafish embryo model. Synthesis of these compounds was carried out with an sp3‐C?H functionalization strategy of methyl quinolines with trifluoromethyl ketones. A zebrafish embryo model was also used to explore the toxicity of ethyl 4,4,4‐trifluoro‐3‐hydroxy‐3‐(quinolin‐2‐ylmethyl)butanoate ( 1 ), 2‐benzyl‐1,1,1‐trifluoro‐3‐(quinolin‐2‐yl)propan‐2‐ol ( 2 ), and trifluoro‐3‐(isoquinolin‐1‐yl)‐2‐(thiophen‐2‐yl)propan‐2‐ol ( 3 ). Compounds 2 and 3 were found to be more toxic than compound 1 ; apoptotic staining assays indicated that compound 3 causes increased cell death. In vitro cell proliferation assays showed that compound 2 , with an LC50 value of 14.14 μm , has more potent anticancer activity than cisplatin. This novel class of inhibitors provides a new direction in the discovery of effective anticancer agents. 相似文献