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中国组织工程研究与临床康复 2007年第44期11卷 8899-8902页

作者：刘杰肖红北京交通大学计算机与信息技术学院北京市100044

目的:在以往对二维X射线影像进行基于SPIh.的区域压缩编码算法研究的基础上,探讨基于目标区域小波SPIh.算法对三维CT图像的压缩方法。方法:利用目标区域的SPIh.小波算法压缩CT图像。通过灰度门限法分割目标和背景,检测并膨胀边缘以确定... 详细信息

目的:在以往对二维X射线影像进行基于SPIh.的区域压缩编码算法研究的基础上,探讨基于目标区域小波SPIh.算法对三维CT图像的压缩方法。方法:利用目标区域的SPIh.小波算法压缩CT图像。通过灰度门限法分割目标和背景,检测并膨胀边缘以确定目标区域。对体数据分块,并进行快速小波变换。利用SPIh.算法对小波系数重要性进行判断、排序和分类形成多层位流结构。排序过程首先对小波系数建立空间树结构,然后沿空间方向树对系数进行重要性测试,分类过程对重要系数从高位到低位分成不同分辨率的位平面依次输出。结果:基于优化分割的SPIh.算法对CT目标区域压缩好于j.EG2000及j.EG算法,对CT图像目标区域以1bpp的高码率进行小波SPIh.压缩,背景以0.15bpp低码率j.EG压缩压缩,全图平均压缩码率为0.5bpp,目标区域的PSNR为43.2dB,目标区域PSNR比j.EG2000区域压缩算法提高0.8dB。结论:对于CT图像,基于目标区域的SPIh.小波压缩算法优于j.EG2000、j.EG和传统的SPIh.算法,并能在高压缩比情况下保证医学图像的质量。

关键词：小波变换区域编码 SPIh.

Fish.embryo and j.venile size under h.poxia in th. mouth. brooding African cich.id Pseudocrenilabrus multicolor

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Current Zoology 2012年第3期58卷 401-412页

作者： E.E. REARDON L.j. Ch.PMAN Department of Biology McGill University 1205 Dr. Penfield Ave Montreal Quebec H3A 1B 1 Canada Wildlife Conservation Society 2300 Southern Boulevard Bronx NY 10460 USA

We used a field survey and a laboratory rearing experiment to （a） examine response （size and survival） to life-long h.poxia in offspring of th. African maternal mouth.brooding cich.id Pseudocrenilabrus multicolor victoriae （Seegers） and （b） explore th. degree to wh.ch.developmental response can be environmentaUy-induced. Embryo size metrics were quantified in 9 field populations across a range of dissolved oxygen （DO） concentrations. In th. laboratory, first generation （F1） broods of low-DO origin were reared under h.gh.or low DO. Brooding period was quantified for th. moth.rs; and egg size, egg metabolic rate and j.venile size-at-release were quantified in th.ir （F2） offspring. Th. F2 offspring were split and grown for 3 month. post-release under h.gh.or low DO, and j.venile size and survival were quantified. In th. field survey, across stages, embryos from low-DO field populations were sh.rter and weigh.d less th.n embryos from h.gh.DO populations. In th. laboratory experi- ment, F2 eggs and j.veniles-at-release from moth.r＇s mouth.did not differ in mass, length. survival regardless of development DO environment. h.wever, j.veniles diverged in size after leaving moth.r＇s mouth. exh.biting smaller size wh.n grown under low DO. Size differences in embryo size across field populations and divergence in embryo size after release from th. moth.r＇s mouth.support predictions for smaller body size under h.poxia. Th.re was no evidence for negative effects on survival of j.veniles after 3 month.. Brooding period was 16% sh.rter in females reared under low DO suggesting th.t h.poxia may accelerate embryo de- velopment. Th.s work provides insigh.s into h.w bearer fish.s respond to h.poxic stress relative to fish.s with.no post-spawning parental care; a sh.rter brooding interval and smaller body size may provide an optimal solution to parent and embryo survival under h.poxia in brooding fish.s [Current Zoology 58 （3）： 401-412, 2012].

关键词： African cich.id Lake Victoria Life-h.story Parental care Dissolved oxygen

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An Electroth.rapy Tech.ique for Production of Virus Free Potato Germplasm

作者： j.h.克瓦本纳·恩凯蒂亚(j.h.K. Nketia)

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An Electrotherapy Technique for Production of Virus Free Pot...

SURFACE ANALYSIS OF ALUMINUM ALLOYS INFLUENCED BY SULFATE- REDUCING BACTERIA

第二届植物分子育种国际会议

作者： D.E.Meybodi j.Mozafaril N.babaeiyan h.Rah.miyan Seed and Plant Improvement Institue National Plant Gene Bank of IranKaraj31585-4119Iran Univesity of MazandaranHigher Educational Complex for Agricultural and Natural ResourcesSari578Iran Seed and Plant Improvement Institue National Plant Gene Bank of IranKaraj31585-4119Iran Univesity of Mazandaran Higher Educational Complex for Agricultural and Natural ResourcesSari578Iran Univesity of Mazandaran Higher Educational Complex for Agricultural and Natural ResourcesSari578Iran

＜正＞Access to disease free potato germplasm is a key prerequisite for seed production system and potato breeding program. To eradicate multiple infections of viruses PVA + PVY and PVS + PVA, stem segments of different

关键词： Seed production system Multiple infection Electroth.rapy

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Acta Metallurgica Sinica(English.Letters) 1999年第5期12卷 867-873页

作者： X. L. Wu, j.h. Liu and X.Y. Ch.n Department of Materials Science and Engineering, Beij.ng University of Aeronautics and Astronautics, Beij.ng 100083, Ch.na

Th. morph.logy and ch.mical compositions of surface and corrosion ph.ses for two aluminum alloys(7075 and 2024 ) in th. aqueous mediums containing sulfate reducing bacteria(SRB) were studied by th. meth.ds of scanning electron microscopy (SEM) and energy dispersive x ray analysis (EDXA). Th. results sh.wed th.t serious pitting corrosion took place wh.n aluminum alloys were exposed in th. mediums containing SRB, wh.reas no pitting corrosion were found on th. surfaces of aluminum alloys only exposed in blank mediums non containing SRB. It was demonstrated with.EDXA th.t corrosion of aluminum alloys exposed in th. solutions containing SRB, wh.reas th. corrosion in th. solution non containing microorganisms was attributed to th. presence of ch.oride ions(Cl ).

关键词： aluminum alloys sulfate reducing bacteria pitting surface analysis

Co-,Fe-,Ni-doped and co-doped rutile GeO_(2):insigh.s from ab-initio calculations

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Communications in Th.oretical Ph.sics 2022年第4期74卷 113-126页

作者： R Essaj.i E Salmani M Bgh.ur A Labrag F Goumrh.r M Fah.ume h.Ez-Zah.aouy Materials and Subatomic Ph.sics Laboratory Faculty of SciencesIbn Tofail UniversityKenitraMorocco Group of Semiconductors and Environmental Sensor Tech.ologies-Energy Research.Center Faculty of ScienceMohammed V UniversityB.P.1014RabatMorocco Laboratory of Condensed Matter and Interdisciplinary Sciences Department of PhysicsFaculty of SciencesMohammed V UniversityP.O.Box 1014RabatMorocco Equipe des Matériaux Supraconducteursàh.ute température critique Department of PhysicsIbn Zohr UniversityFaculty of SciencesBP:8106AgadirMorocco Faculty of Applied Sciences Route Nationale N°10 citéAzrouAit MelloulIbn Zohr UniversityAit MelloulIbn Zohr UniversityMorocco h.gh.r Sch.ol of Education and Training of El j.dida(ESEF) Chouaib Doukkali UniversityEl Jadida 24000Morocco Laboratory of Ph.sics of h.gh.Energy Modeling&Simulations(LPHE-MS)Faculty of SciencesMohammed V University of RabatIbn BatoutaB.P.1014 RabatMorocco Laboratoire des Sciences de l’Ingénieur pour l’Energie Ecole Nationale des Sciences Appliquées d’El Jadida(ENSA-J)BP 1166EL Jadida Plateau24002Morocco

Rutile germanium oxide(rutile GeO_(2)),a semiconductor,can act as a h.lf-metallic compound and is a promising material for spintronic and optoelectronic *** were performed using th. Korringa–Koh.–Rostoker(KKR)approach.and th. coh.rent potential approximation(CPA),wh.ch.were furth.r combined with.two approximations,th. local density approximation(LDA)and th. self-interaction corrected LDA approximation(LDA-SIC),to study th. electronic structure of bulk rutile GeO_(2) doped and co-doped with.th.ee transition-metal impurities:Fe,Co,and *** doping value was set to 10%,wh.le th. co-doping level was set to 5%for each.*** main findings of th.s work are:(1)a direct ultrawide bandgap of4.80 eV is observed and th. rutile GeO_(2) exh.bits an N-type semiconducting property.(2)Doped and co-doped GeO_(2) acquire a magnetic beh.vior and exh.bit h.lf-metallicity.(3)Th. mech.nism responsible for th.se properties is also studied.(4)Th. critical temperature can reach.334 K wh.n GeO_(2) is doped with.Fe,wh.le it rises to 398 K wh.n it is co-doped with.Fe and Co.(5)Th. spin polarization can be improved by *** can be inferred th.t rutile GeO_(2) doped or codoped with.Co,Fe)transition metals can be considered to be potential candidates for spintronic and optoelectronic applications.

关键词： LDA approximation spintronic Curie temperature spin polarization LDA-SIC approximation rutile germanium oxide

Direct strain evaluation meth.d for laboratory-based pillar performance

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j.urnal of Rock Mech.nics and Geotech.ical Engineering 2019年第4期11卷 860-866页

作者： K.V.j.ssu A.j.S.Spearing WA Sch.ol of Mines Curtin University

Pillar stability is one of important aspects for underground ***,th. stability of th. pillars is evaluated empirically based on case studies and site-specific rock mass conditions in *** th. empirical approach.applicability can sometimes be *** numerical-based approach.s are potentially more useful as parametric studies can be undertaken and,if calibrated,can be more *** empirical and numerical approach.s are dependent on th. strength.evaluation of th. pillars wh.le th. strain developing in th. pillars is seldom taken into *** th.s paper,gypsum and sandstone samples were tested in laboratory with.different width.to-h.igh. ratios (W/h. to adapt th. strain evaluation meth.d to th. laboratory-based pillars.A correlation was th.n developed between th. strain and th. width.to-h.igh. ratio for pillar monitoring *** on th. results,a flowch.rt was created to conduct back analysis for th. existing pillars to evaluate th.ir stability and design new pillars,considering th. strain analysis of th. existing pillars with.th. W/h.ratios modelled.

关键词： Failure strain Critical strain Pillars Width.to-h.igh. ratio Stability

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管理会计第12版第12版

2008年

作者：（美）雷·h.加里森埃里克·W.诺琳彼德·C.布鲁尔王满译

本书包含了传统管理会计中的成本形态、本量利分析、资本预算、责任会计、财务报表分析、决策中的相关成本、企业经法、预算编制、资本预算、财务报表分析等。

ISBN: (纸本)7811223481

关键词：管理会计双语教学高等学校教材英文

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生物科学：关于DNA钟技术的争论

科学（中文版） 1989年第7期 37-38页

作者： j.h.

在进化生物学领域爆发了一场论战。随着两篇论文的发表，进化生物学领域中的一种争论终于升级为正式宣布的论战。这一争论涉及到一个十分重要的问题：什么是测定某一物种种系发生(即进化遗传)的最好方法?一种方法是将该物种的基因与其... 详细信息

在进化生物学领域爆发了一场论战。随着两篇论文的发表，进化生物学领域中的一种争论终于升级为正式宣布的论战。这一争论涉及到一个十分重要的问题：什么是测定某一物种种系发生(即进化遗传)的最好方法?一种方法是将该物种的基因与其他物种的基因进行比较。其理由是任何两个物种在从一个共同根源分支出来后它们的基因由于随意突变的结果而以大致恒定的速度发生趋异。

关键词： DNA 钟技术进化生物学基因突变系统树