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雷达频率综合器综述

航空兵器 1992年第1期 43-52页

作者： zvi galani Richard A.Campbell 曹旭东 IEE IEE 高级会员高级会员

本文综述了适用于雷达系统的频率综合技术和雷达系统对频率综合器的要求——这对于选择频率综合方法和选用频综器器件有着直接的影响;讨论了直接频率综合方案和间接频率综合方案以及它们各自的优缺点,并提供了具有代表性的实例。本文还... 详细信息

本文综述了适用于雷达系统的频率综合技术和雷达系统对频率综合器的要求——这对于选择频率综合方法和选用频综器器件有着直接的影响;讨论了直接频率综合方案和间接频率综合方案以及它们各自的优缺点,并提供了具有代表性的实例。本文还对分析步骤进行了简要的讨论,并对频综器的关键器件及其发展趋势进行了评述。

关键词：雷达频率综合器

What If I Told You Camouflage is a Myth? Animal Coloration is Mainly A-biotic and not Biotic (Camouflage)

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Research in Ecology 2024年第1期6卷 14-27页

作者： zvi Sever Formerly Biology Department University of IndianapolisIndiana46227USA

In the present article,the author posits that the perception that animals apparently display a strategy of avoiding detection by means of camouflage—i.e.,by disguising themselves in the natural colours of their environment—is not the actual case in nature but,rather,merely *** coloration is mainly a-biotic(eco-physiological)and not biotic(camouflage).The contention regarding the absence of the phenomenon of camouflage among animals as a common evolutionary response is based on three arguments:(1)that reflecting the natural colours of the environment is linked to ecophysiology;(2)that predator and prey constitute“an evolutionary pair”and,accordingly,they know how to identify one another(in order to survive they employ different strategies,of which camouflage is not one of them);and (3)that the approach of relating animal camouflage to reflecting the colours of the environment is an anthropocentric *** than the accepted biotic-ethological approach(colour camouflage),the present article suggests the recognition of a-biotic and eco-physiological conditions as a distinct research field,whose title“Reflection of environmental colours by animals”,along with this article,calls for eco-physiologists to demonstrate that this approach indeed offers a special contribution to the understanding of colouration in animals.

关键词： A-biotic Anthropocentrism Camouflage Eco-physiology Ethology Evolution Reflection

Determination of creatinine level in patient blood samples by Fourier NIR spectroscopy and multivariate analysis in comparison with biochemical assay

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Journal of Innovative Optical Health Sciences 2019年第6期12卷 46-55页

作者： zvi Hai Barnea(Burbea) David Abookasis Nephrology Department Edith Wolfson Hospital Holon 5822012Israel Sackler Faculty of Medicine Tel Aviv University Ramat Aviv 6997801Israel Department of Electrical and Electronics Engineering Ariel University Ariel 4070000Israel

In this paper,in vivo spectra from 23 patients'blood samples with various Creatinine(Cr)concentration levels ranging from 0.96 to 12.5 mg/dL were measured using Fourier transform near-infrared spectrometer(FT-NIRS)and spectrum quantitative analysis *** Cr undergoes passive filtration,it serves as a key biomarker of kidneys function via the estimation of glomerular filtration ***,increased blood Cr concentration reflects impaired renal *** spectra pre processing and outlier exclusion,a spectral model was developed based on partial least squares regression(PLSR)method,wherein Cr concentrations correlated with filtered NIR spectra across several peaks,where Cr is know n to absorb NIR *** statistical metrics were applied to estimate the model efficiency during data *** of spectra-derived concentrations to reference Cr measurements by the current gold-standard Jaffe's method held in hospital lab revealed a Cr prediction accuracy of 1.64 mg/dL with good corre-lation of R=***-Altman plots were used to compare between our calculations and ref-erence lab values and reveal minimal bias between the *** finding presented the potential of FT-NIRS coupled with PLSR technique for Cr determination.

关键词： Creatinine Fourier transform near infrared spectroscopy blood samples chemo metrics statistical analysis

The energy transfer mechanism of a perturbed solid-body rotation flow in a rotating pipe

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Acta Mechanica Sinica 2017年第2期33卷 274-283页

作者： Chunjuan Feng Feng Liu zvi Rusak Shixiao Wang School of Aeronautics Northwestern Polytecrhnical University Department of Mechanical and Aerospace Engineering University of California Department of Mechanical Aerospaceand Nuclear EngineeringRensselaer Polytechnic Institute Department of Mathematics University of Auckland

Three-dimensional direct numerical simulations of a solid-body rotation superposed on a uniform axial flow entering a rotating constant-area pipe of finite length are presented. Steady in time profiles of the radial, axial, and circumferential velocities are imposed at the pipe inlet. Convective boundary conditions are imposed at the pipe outlet. The Wang and Rusak (Phys. Fluids 8:1007-1016, 1996.) axisymmetric instability mechanism is retrieved at certain operational conditions in terms of incoming flow swirl levels and the Reynolds number. However, at other operational conditions there exists a dominant, three-dimensional spiral type of instability mode that is consistent with the linear stability theory of Wang et al. (J. Fluid Mech. 797: 284-321, 2016). The growth of this mode leads to a spiral type of flow roll-up that subsequently nonlinearly saturates on a large amplitude rotating spiral wave. The energy transfer mechanism between the bulk of the flow and the perturbations is studied by the Reynolds-Orr equation. The production or loss of the perturbation kinetic energy is combined of three components: the viscous loss, the convective loss at the pipe outlet, and the gain of energy at the outlet through the work done by the pressure perturbation. The energy transfer in the nonlinear stage is shown to be a natural extension of the linear stage with a nonlinear saturated process.

关键词： Vortex instability Incompressible viscous flow Cylindrical coordinates

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Post-pyloric feeding

World Journal of Gastroenterology 2009年第11期15卷 1281-1288页

作者： Eva Niv zvi Fireman Nachum Vaisman Department of Gastroenterology Hillel Yaffe Medical Center Hadera 38100 Israel The Unit of Clinical Nutrition Tel Aviv Sourasky Medical Center Tel Aviv 6974444 Israel

Postpyloric feeding is an important and promising alternative to parenteral nutrition. The indications for this kind of feeding are increasing and include a variety of clinical conditions, such as gastroparesis, acute pancreatitis, gastric outlet stenosis, hyperemesis (including gravida), recurrent aspiration, tracheoesophageal fistula and stenosis in gastroenterostomy. This review discusses the differences between pre- and postpyloric feeding, indications and contraindications, advantages and disadvantages, and provides an overview of the techniques of placement of various postpyloric devices.

关键词： Postpyloric feeding Nasojejunal feeding Nasojejunal tube Jejunostomy Nasoenteric tube Percutaneous endoscopic gastrostomy-jejunostomytube Percutaneous endoscopic jejunostomy

Diffuse transmitted spectroscopy in conjunction with spectral peak averaging as a potential tool for noninvasive creatinine screening

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Journal of Innovative Optical Health Sciences 2020年第6期3卷 71-80页

作者： zvi Hai Barnea(Burbea) Shmuel Zimlichman David Abookasis Nephrology Department Edith Wolfson HospitalHolon 5822012Israel Sackler Faculty of Medicine Tel Aviv University P.O.Box 39040Tel Aviv 6997801Israel Department of Electrical and Electronics Engineering Ariel University Ariel 4070000Israel

Creatinine(Cr)is a biochemical waste molecule generated from muscle metabolism and primarily cleared from the bloodstream by the *** kidney function declines,Cr levels in the blood tend to ***,Cr serves as an indicator of kidney *** this work,we present a simple method for the rapid screening for impaired renal function based on the subject's Cr *** our setup,broadband white light is delivered to a finger clamp through a fiber-optic cable to illuminate the patient's *** light is transmitted through the finger and collected by a second optical fiber coupled to a visible-near-infrared(VisNIR)spectrometer which covers the spectral range from 400nm to *** the calibration process,the transmitted spectra acquired from 60 patients were *** average was calculated using the peak level of the transmitted,diffused intensity at three different wavelengths to create a"Cr intensity index".Patients were divided into five groups according to their Cr concentration levels,ranging from 1 mg/dL to 13 mg/*** observations indicated that each group featured a unique spectral ***,we tested the index on 20 patients not included in the cali-bration procedure(unknown samples).We were able to classify patients into groups according to their Cr level with moderate prediction accuracy(R^(2)=0.55)and mean screening error of up to 16%.Future efforts will evaluate the accuracy of this approach with larger patient populations representing a broad range of Cr ***,this preliminary work is an essential step toward developing this useful noninvasive Cr screening platform using NIR light spectroscopy.

关键词： Creatinine near-infrared spectroscopy spectral peak averaging patient finger prediction

Sesame response to nitrogen management under contrasting water availabilities

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Oil Crop Science 2022年第4期7卷 166-173页

作者： Elnatan Golan zvi Peleg Zipora Tietel Ran Erel Gilat Research Center Agricultural Research OrganizationIsrael The Robert H.Smith Faculty of Agriculture Food and EnvironmentThe Hebrew University of JerusalemIsrael

Sesame is mainly cultivated under traditional,low-input *** breeding developments promoted the modernization and mechanization of sesame ***,only a few articles have been published concerning fertilization requirements for both modern and traditional *** field trials at two locations,we determined the response of irrigated sesame to nitrogen(N).Three promising sesame lines were tested combining two irrigation levels with four N *** a high irrigation level,N had a significant effect on growth,branching,and consequently,seed yield exceeding two-ton ha^(-1).A high N doze was accompanied by a decrease in the photosynthetic rate and leaf water *** δ^(13)C confirmed lower stomatal conductance under high N *** deficit irrigation,the N level had a minor effect on the monitored parameters,indicating N fertilization was not *** oil content was negatively correlated with seed N *** results question the necessity of N application when water is limited,as N fertilization promotes vigorous development that rapidly depletes soil ***,water availability should be considered when developing an N management *** high-yielding agro-systems,roughly 80–120 kg ha^(-1)N is required for optimal yield,bearing in mind the negative association between seed-N and oil content.

关键词： Nitrogen-use efficiency Seed-oil Irrigation Fertigation

Hairy cell leukemia presenting as multiple discrete hepatic lesions

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World Journal of Gastroenterology 2009年第35期15卷 4453-4456页

作者： Nadav Sahar Ginette Schiby Tima Davidson Abraham Kneller Sara Apter zvi Farfel Department of Medicine E Sheba Medical CenterTel Hashomer 52621and Sackler Faculty of MedicineTel Aviv UniversityTel AvivIsrael Department of Pathology Sheba Medical CenterTel Hashomer 52621and Sackler Faculty of MedicineTel Aviv UniversityTel AvivIsrael Department of Nuclear Medicine Sheba Medical CenterTel Hashomer 52621and Sackler Faculty of MedicineTel Aviv UniversityTel AvivIsrael Department of Hematology Sheba Medical CenterTel Hashomer 52621and Sackler Faculty of MedicineTel Aviv UniversityTel AvivIsrael Departments of Diagnostic Radiology Sheba Medical CenterTel Hashomer 52621and Sackler Faculty of MedicineTel Aviv UniversityTel AvivIsrael

The involvement of hairy cell leukemia in the liver is in the form of portal and sinusoidal cellular infiltration. Here we describe the first case of hepatic hairy cell leukemia presenting as multiple discrete lesions,which was treated *** suggest that in the inves- tigation of discrete hepatic lesions in cases of cancer of unknown primary,hairy cell leukemia should be consid- *** excellent response of hairy cell leukemia to therapy highlights the need for such a consideration.

关键词： Cancer of unknown primary Hairy cell leukemia Hepatic lesions

FATTY ACIDS PROFILE IN A HIGH CELL DENSITY CULTURE OF ARACHIDONIC ACID-RICH PARIETOCHLORIS INCISA (TREBOUXIOPHYCEAE,CHLOROPHYTA) EXPOSED TO HIGH PFD

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Chinese Journal of Oceanology and Limnology 2002年第2期20卷 149-156页

作者：刘建国 zvi Cohen 等 ResearchandDevelopmentCenterofMarineBIotechnolgy InstituteofOceanologyChineseAcademyofSciencesQingdao266071China MicroalgalBiotechnology TheJacobBlausteinInstituteforDesertResea

The changes in arachidonic acid (AA) and fatty acids profiles along the growth curve of Parietochloris incisa, a coccoid snow green alga, were studied in a 2.8 cm light-path flat photobioreactor, exposed to strong photon flux density [PFD, 2400 μEmol/(m 2·s)]. Sixteen fatty acids were identified by gas chromatography showing that AA was the dominant fatty acid (33%-41%) followed by linoleic acid (17%-21%). AA content was closely investigated with respect to total fatty acids (TFA), ash free dry weight (AFDW) of cell mass as well as total culture content. These parameters were influenced significantly in a similar manner by culture growth phase, i.e., slightly decreasing in the lag period, gradually increasing in the logarithmic phase, becoming maximal at the early stationary phase, starting to decrease at the late stationary phase, sharply dropping at the decline phase. The increase in AA per culture volume during the logarithmic phase was not only associated with the increase in AFDW but also connected with a corresponding increase in AA/TFA, TFA/AFDW as well as AA/AFDW. The sharp decrease in AA content of the culture during the decline phase was mainly due to the decrease in AA/TFA, TFA/AFDW and AA/AFDW, although AFDW declined only a small extent. Maximal AA concentration, obtained at the early stationary phase, was 900 mg/L culture volume, and the average daily net increase of AA during 9 days logarithmic growth was 1.7 g/(m 2·day). Therefore, harvesting prior to the decline phase in a batch culture, or at steady state in continuous culture mode seems best for high AA production. The latter possibility was also further confirmed by continuous culture with 5 gradients of harvesting rate.

关键词： arachidonic acid Parietochloris incisa growth high cell density culture