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A UWB communication system based on dechirp pulse compression and OOK modulation

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High Technology Letters 2013年第2期19卷 190-196页

作者：赵亮 Jin Liang Huang Kaizhi Zhang Jian Chen Jinyu National Digital Switching System Engineering & technological R&D center

In this paper,a novel UWB communication system structure is *** transmitted signal uses OOK modulation and chirp spread *** received signal first goes through a dechirp pulse compression process,and then is processed with a two-level sliding correlation algorithm for coarse timing synchronization and fine timing *** the SNR estimation,the signal is demodulated by an energy detection *** integrated system level simulation model is established,and the performance of this system is evaluated over the AWGN channel,IEEE 802.15.3a CM1 and CM4 *** theoretical analysis and simulation results show that this UWB communication system can effectively reduce the sampling rate and signal processing speed at the receiver,and it is more suitable for long-distance and low-rate UWB communications with high spreading gain.

关键词： uhra wide band (UWB) dechirp pulse compression on-off keying (OOK) sliding correlation BER

Secret Key Generation Based on Two-Way Randomness for TDD-SISO System

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China Communications 2018年第7期15卷 202-216页

作者： Shengjun Zhang Liang Jin Yangming Lou Zhou Zhong National Digital Switching System Engineering&technological Research center Zhengzhou 450002China

A novel secret key generation(SKG)method based on two-way randomness is proposed for TDD-SISO *** legitimate transceivers mutually transmit their own random signal via reciprocal wireless channel,then the multiplication of transmitted and received signal is used as common randomness to generate secret *** quasi-static channel,the theoretical SKG rates(SKGRs)of the three SKG methods,namely wireless channel based,one-way randomness and two-way randomness,are derived and ***,two practical SKG schemes based on twoway randomness,Scheme-1bit and Scheme-3bit,are completely designed and ***,Scheme-1bit applies to low signal to noise ratio(SNR)scenarios and achieves 0.13~0.86bit/T_s SKGR and 10^(-2)~10^(-5) level secret key outage probability(SKOP),while Scheme-3bit fits high SNR situation and obtains 0.93~1.35bit/T_s SKGR and 10^(-3)~10^(-4) level *** last,the national institute of standards and technology(NIST)test is conducted to evaluate the secret key randomness(SKRD)and the test results show that both of the proposed schemes have passed the test.

关键词： secret key generation physical layer security information reconciliation information theory

Endoscopic ultrasound guided radiofrequency ablation for pancreatic tumors: A critical review focusing on safety, efficacy and controversies

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World Journal of Gastroenterology 2023年第1期29卷 157-170页

作者： Tawfik Khoury Wisam Sbeit Bertrand Napoléon Department of Gastroenterology Galilee Medical CenterNahariya 2210001Israel Department of Endoscopy Unit Private Hospital Jean MermozLyon 69008France

The role of endoscopic ultrasound(EUS)in the last two decades has shifted from a diagnostic tool to an important therapeutic tool treating mainly pancreatobiliary *** recent years,its applications for treating pancreatic diseases have broadened,including the implementation of radiofrequency ablation(RFA),which has been traditionally used for treating solid *** this critical indepth review,we summarized all the papers throughout the literature regarding EUS-RFA for pancreatic neuroendocrine neoplasms,adenocarcinoma,and pancreatic cystic ***,for pancreatic neuroendocrine neoplasms we identified 16 papers that reported 96 patients who underwent EUS-RFA,with acceptable adverse events that were rated mild to moderate and a high complete radiological resolution rate of 90%.For pancreatic adenocarcinoma,we identified 8 papers with 121 *** events occurred in 13%of patients,mostly rated ***,no clear survival benefit was *** pancreatic cystic lesions,we identified 4 papers with 38 *** adverse events were mostly mild and occurred in 9.1%of patients,and complete or partial radiological resolution of the cysts was reported in 36.8%.Notably,the procedure was technically feasible for most of the ***,a long road remains before this technique finds its definite place in guidelines due to several ***-RFA for pancreatic tumors seems to be safe and effective,especially for pancreatic neuroendocrine neoplasms,but multicenter prospective trials are needed to consider this treatment as a gold standard.

关键词： Endoscopic ultrasound Radiofrequency ablation Efficacy Safety Pancreas Tumors

Constitutive expression of feedback-insensitive cystathionine γ-synthase increases methionine levels in soybean leaves and seeds

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Journal of Integrative Agriculture 2018年第1期17卷 54-62页

作者： YU Yang HOU Wen-sheng Yael Hacham SUN Shi WU Cun-xiang Ifat Matityahu SONG Shi-kui Rachel Amir HAN Tian-fu Key Laboratory of Soybean Biology (Beijing) Ministry of Agriculture/Institute of Crop Sciences Chinese Academy of Agricultural Sciences Beijing 100081 P.R.China Laboratory of Plant Science Migal Galilee Technology Center Kiryat Shmona 12100 Israel TeI-Hai College Upper Galilee 11016 Israel

Soybean （Glycine max （L.） Merr.） is a major crop that provides plant-origin protein and oil for humans and livestock. Al- though the soybean vegetative tissues and seeds provide a major source of high-quality protein, they suffer from low con- centration of an essential sulfur-containing amino acid, methionine, which significantly limits their nutritional quality. The level of methionine is mainly controlled by the first unique enzyme of methionine synthesis, cystathione y-synthase （CGS）. Aiming to elevate methionine level in vegetative tissues and seeds, we constitutively over-expressed a feedback-insensitive Arabidopsis CGS （AtD-CGS） in soybean cultivars, Zigongdongdou （ZD） and Jilinxiaoli 1 （JX）. The levels of soluble methionine increased remarkably in leaves of transgenic soybeans compared to wild-type plants （6.6- and 7.3-fold in two transgenic ZD lines, and 3.7-fold in one transgenic JX line）. Furthermore, the total methionine contents were significantly increased in seeds of the transgenic ZD lines （1.5- to 4.8-fold increase） and the transgenic JX lines （1.3- to 2.3-fold increase） than in the wild type. The protein contents of the transgenic soybean seeds were significantly elevated compared to the wild type, suggesting that the scarcity of methionine in soybeans may limit protein accumulation in soybean seeds. The increased protein content did not alter the profile of major storage proteins in the seeds. Generally, this study provides a promising strategy to increase the levels of methionine and protein in soybean through the breeding programs.

关键词： soybean (Glycine max (L.) Merr.) constitutive expression cystathionine y-synthase (CGS) methionine contentstorage protein

Analysis of Nonlinear Directional Couplers

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光学学报 2003年第S1期23卷 102-103页

作者： M. Liu P. Shum N. Q. Ngo Network Technology Research center Nanyang Technological University Singapore 639798Network Technology Research Center Nanyang Technological University Singapore 639798Network Technology Research Center Nanyang Technological University Singapore 639798

1 IntroductionSince the coupled-mode theory in cylindrical optical-fiber systems was proposed in 1972, the optical coupling between parallel optical waveguides has been a matter of scientific concern. Two-core fiber couplers, especially, have been studied extensively since the success of producing a two-core fiber functioning as a directional coupler in 1980. The wavelength and polarization selectivity of two-core fibers can find many applications. The nonlinear properties of the two-core fiber coupler ...

关键词： of on as been have Analysis of Nonlinear Directional Couplers that

Private Proximity Detection for Convex Polygons

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Tsinghua Science and Technology 2016年第3期21卷 270-280页

作者： Bin Mu Spiridon Bakiras Department of Computer Science Graduate Center City University of New York Department of Computer Science Michigan Technological University

Proximity detection is an emerging technology in Geo-Social Networks that notifies mobile users when they are in proximity. Nevertheless, users may be unwilling to participate in such applications if they are required to disclose their exact locations to a centralized server and/or their social friends. To this end, private proximity detection protocols allow any two parties to test for proximity while maintaining their locations secret. In particular, a private proximity detection query returns only a boolean result to the querier and, in addition, it guarantees that no party can derive any information regarding the other party＇s location. However, most of the existing protocols rely on simple grid decompositions of the space and assume that two users are in proximity when they are located inside the same grid cell. In this paper, we extend the notion of private proximity detection, and propose a novel approach that allows a mobile user to define an arbitrary convex polygon on the map and test whether his friends are located therein. Our solution employs a secure two-party computation protocol and is provably secure. We implemented our method on handheld devices and illustrate its efficiency in terms of both computational and communication costs.

关键词： proximity detection secure computations location privacy

Olive oil consumption and non-alcoholic fatty liver disease

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World Journal of Gastroenterology 2009年第15期15卷 1809-1815页

作者： Nimer Assy Faris Nassar Gattas Nasser Maria Grosovski Liver Unit Ziv Medical CenterSafedIsrael Faculty of Medicine Technion Institute Department of Medicine Western Galilee Hospital Department of Biotechnology Ort-Braude College

The clinical implications of non-alcoholic fatty liver diseases(NAFLD)derive from their potential to progress to fibrosis and *** dietary fat intake,excessive intake of soft drinks,insulin resistance and increased oxidative stress results in increased free fatty acid delivery to the liver and increased hepatic triglyceride(TG)*** olive oil-rich diet decreases accumulation of TGs in the liver,improves postprandial TGs,glucose and glucagonlike peptide-1 responses in insulin-resistant subjects, and upregulates glucose transporter-2 expression in the *** principal mechanisms include:decreased nuclear factor-kappaB activation,decreased lowdensity lipoprotein oxidation,and improved insulin resistance by reduced production of inflammatory cytokines(tumor necrosis factor,interleukin-6)and improvement of jun N-terminal kinase-mediated phosphorylation of insulin receptor *** beneficial effect of the Mediterranean diet is derived from monounsaturated fatty acids,mainly from olive *** this review,we describe the dietary sources of the monounsaturated fatty acids,the composition of olive oil,dietary fats and their relationship to insulin resistance and postprandial lipid and glucose responses in non-alcoholic steatohepatitis,clinical and experimental studies that assess the relationship between olive oil and NAFLD,and the mechanism by which olive oil ameliorates fatty liver,and we discuss future perspectives.

关键词： Liver steatosis Fatty liver Olive oil Fatty acids Monounsaturated Non-alcoholic steatohepatitis Lipids Oleic acid Non-alcoholic fatty liver disease

An Efficient Algebraic Solution for Moving Source Localization from Quadruple Hybrid Measurements

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Chinese Journal of Electronics 2022年第2期31卷 255-265页

作者： DING Ting ZHAO Yongsheng ZHAO Yongjun Henan High-Speed Railway Operation and technological Research center PLA Strategic Support Force Information Engineering University

This paper deals with the 3-D moving source localization using time difference of arrival(TDOA), frequency difference of arrival(FDOA), angle of arrival(AOA) and AOA rate measurements, gathered from a set of spatially distributed receivers. The TDOA,FDOA, AOA and AOA rate measurement equations were firstly established according to the space geometric relationship of the source relative to the receivers. Then an efficient closed-form algorithm for source position and velocity estimation from the quadruple hybrid measurements was proposed. The proposed algorithm converts the nonlinear measurement equations into a linear set of equations, which can then be used to estimate the source position and velocity applying weighted least square(WLS) minimization. In contrast to existing two-stage WLS algorithms, the proposed algorithm does not introduce any nuisance parameters and requires merely onestage, which enables for source localization with the fewest receivers necessary. Theoretical accuracy analysis shows that the proposed algorithm reaches the CramerRao lower bound, and simulation studies corroborate the efficiency and superiority of the proposed algorithm over other algorithms.

关键词： algebraic solution AOA rate measurement equations position measurement velocity estimation angle of arrival spatially distributed receivers Cramer-Rao lower bound source separation least squares approximations closed-form algorithm time difference of arrival two-stage WLS algorithms quadruple hybrid measurements time-of-arrival estimation source position weighted least square minimization frequency difference of arrival TDOA nonlinear measurement equations 3D moving source localization minimisation velocity measurement space geometric relationship direction-of-arrival estimation

Design by Analogy:Achieving More Patentable Ideas from One Creative Design

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Chinese Journal of Mechanical Engineering 2018年第2期31卷 25-34页

作者： Li-Zhen Jia Chun-Long Wu Xue-Hong Zhu Run-Hua Tan Civil Aviation University of China Hebei University of Technology National Engineering Research center for technological Innovation Method and Tool

A patent is a kind of technical document to protect intellectual property for individuals or enterprises. Patentable idea generation is a crucial step for patent application and analogy is confirmed to be an effective technique to inspire creative ideas. Analogy?based design usually starts from representation of an analogy source and is followed by the retrieval of appropriate analogs, mapping of design knowledge and adaptation of target solution. To diffuse one core idea into other new contexts and achieve more patentable ideas, this paper mainly centered on the first two stages of analogy?based design and proposed a patentable ideation framework. The analogical information of the source system, including source design problems and solution, was mined comprehensively through International Patent Classification analysis and represented in the form of function, behavior and structure. Three heuristics were suggested for searching the set of candidate target systems with a similar design problem, where the source design could be transferred. To systematize the process of source representation, analogs retrieval, idea transfer, and solution generation, an ideation model was put forward. Finally, the bladeless fan was selected as a source design to illustrate the application of this work. The design output shows that the representation and heuristics are beneficial, and this systematic ideation method can help the engineer or designer enhance creativity and discover more patentable opportunities.

关键词： Design by analogy Patentable idea generation IPC analysis Idea transfer heuristics Bladeless fan