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A comparison study of image segmentation by clustering techniques

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A comparison study of image segmentation by clustering techn...

1996 3rd International Conference on Signal Processing(ICSP’96)

作者： f.Z Kettaf D.BI J.P.Asselin de Beauville Laboratoire d’Informatique Ecole d’Ingnicurs en Informatique pour I’Industric 64 avenue Jean PortalisBoe n°4 37913 Tours Cedex 09France Laboratoire d’Informatique Ecole d’Ingnicurs en Informatique pour I’Industric 64 avenue Jean PortalisBoe n°4 37913 Tours Cedex 09France

＜正＞Many image segmentation based on clustering techniques are available in the *** of these techniques use classical clustering,some use fuzzy sets *** most of these techniques are not suitable for noisy *** works have been done using possibilist clustering approach which is robust to noise,but require the knowledge of the number of *** probabilistic approach can be used to assess the number of *** paper reviews and summarizes some of these *** have been made to cover hard,fuzzy and possibilist approaches as well as the mixture model *** attention is paid to possibilist clustering in discarding noisy pixels and to entropic criteria in assessing the number of clusters,we also propose a quantitative evaluation of segmentation results.

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从磷酸中同时萃取稀土元素和铀

湿法冶金 1993年第2期12卷 53-57页

作者： f.Bunus 张重铭

在有或无三-n-辛基磷氧化物(TOPO)存在的情况下,用二(2-乙基己基)磷酸(DEPA)溶剂萃取法从膦酸中提取铀时,稀土元素(REEs)得到萃取。对此,至今还没有引起人们注意.REEs是在有和无U(Ⅳ)的情况下以氟化物形式提取出来的。本研究是对引入磷... 详细信息

在有或无三-n-辛基磷氧化物(TOPO)存在的情况下,用二(2-乙基己基)磷酸(DEPA)溶剂萃取法从膦酸中提取铀时,稀土元素(REEs)得到萃取。对此,至今还没有引起人们注意.REEs是在有和无U(Ⅳ)的情况下以氟化物形式提取出来的。本研究是对引入磷酸介质中的REEs系列的每一元素采用放射性同位素来进行的.REEs的回收过程,制得含稀土元素浓缩物的产品。试验研究中,所采用的两种工业萃取剂为DEPA和苯基膦酸。还用磷氮溶液进行了类似试验研究.试验证明,从磷酸介质中萃取对钇有利;而从磷氮溶液中萃取,则对铈和钇有利.因此,在回收过程中,REEs可得到优先分离。

关键词：稀土族铀磷酸萃取

低剂量儿童冠状动脉CT检查有效辐射剂量与影像质量的评估

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国际医学放射学杂志 2016年第5期 581-581页

作者： B.H.Geryes R.Calmon D.Khraiche n.Boddaert *** f.Raimondi 李玲 Service de Radiologie pédiatrique Hpital Universitaire Necker Enfants Malades

摘要目的评估儿童冠状动脉CT(c CT)不同扫描方案对辐射剂量以及成像质量的影响。方法纳入2012年1月—2014年6月采用64层CT行c CT的140例儿童。扫描中均采用以下2个参数:自适应统计迭代重建技术(ASIR);对采集参数进行优化。根据有关剂量... 详细信息

摘要目的评估儿童冠状动脉CT(c CT)不同扫描方案对辐射剂量以及成像质量的影响。方法纳入2012年1月—2014年6月采用64层CT行c CT的140例儿童。扫描中均采用以下2个参数:自适应统计迭代重建技术(ASIR);对采集参数进行优化。根据有关剂量长度积(DLP)计算有效剂量

关键词：影像质量辐射剂量冠状动脉儿童 CT

整形对密植苹果树生长、产量、水分消耗和营养吸收的影响

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国外农学（果树） 1990年第2期 1-3页

作者： Leuz.f. 程瑞平

以一年生金冠/M9和乔纳金/M9苹果树为试材,采用渗漏试验和田间试验,比较4种树形,即荷兰纺锤形、细长纺锤形、不修剪并经PP333处理和不修剪对照树对水分、矿质营养的吸收和分布及叶片、产量、干物质分配等影响。5年所得结果表明,金冠苹... 详细信息

以一年生金冠/M9和乔纳金/M9苹果树为试材,采用渗漏试验和田间试验,比较4种树形,即荷兰纺锤形、细长纺锤形、不修剪并经PP333处理和不修剪对照树对水分、矿质营养的吸收和分布及叶片、产量、干物质分配等影响。5年所得结果表明,金冠苹果不修剪的叶面积和产量均最高,以下是细长纺锤形和PP333处理树。荷兰纺锤形的叶面积虽小,但单个叶片最大。单株的干物质含量也以不修剪树为最高,荷兰纺锤形最低。不同整形方法树体的n、P、K含量和分布也各异。

关键词：苹果树密植整枝水分营养产量

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鸟类褪黑激素及其受体研究进展

国外畜牧科技 1997年第6期24卷 37-41页

作者： S.f.Pang 王娜

鸟类褪黑激素及其受体研究进展Ｓ．Ｆ．Ｐａｎｇ（香港）等著王娜摘译贾志海校１引言褪黑激素（Ｍｅｌａｔｏｎｉｎ，ＭＬＴ），即Ｎ－乙酰－５－甲氧基色胺，最初是从牛松果体中分离出来的（Ｌｅｒｎｅｒ等，１９５８）。鸟类和哺乳动... 详细信息

鸟类褪黑激素及其受体研究进展Ｓ．Ｆ．Ｐａｎｇ（香港）等著王娜摘译贾志海校１引言褪黑激素（Ｍｅｌａｔｏｎｉｎ，ＭＬＴ），即Ｎ－乙酰－５－甲氧基色胺，最初是从牛松果体中分离出来的（Ｌｅｒｎｅｒ等，１９５８）。鸟类和哺乳动物的松果体都分泌这种激素。在大鼠的...

关键词：鸟类褪黑激素受体

ZEOLITE SYnTHESIS fROM A HIGH SI-AL-fLY ASH fROM EAST CHInA

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ZEOLITE SYNTHESIS FROM A HIGH SI-AL-FLY ASH FROM EAST CHINA

中国科学院地质与地球物理研究所2002学术年会

作者： J.C.Umaa X.Querol A.Lopez-Soler f.Plana Instittute of Earth Sciences CSICLluis Sole i Sabaris s/n.08028-Barcelona Spain

A high Al-Si Chinese fly ash from Dou He power plant(Tangshan city,Hebei Province, Eastern China) was selected as starting material of the zeolitization *** material was obtained by conventional alkaline activation by using naOH and KOH *** synthesis process was optimized by applying a wide ranges of reaction temperature,time and activation agent concentrations.A high solution / fly ash ratio was used in order to allow dissolution of highly resistant Al-Si phases such as *** synthesis yields were obtained by using both KOH and naOH *** products reached a cation exchange capacity(CEC) up to 2.3 meq *** zeolites obtained with a high CEC were:naP1,KM and f linde *** low contents of major impurities of this fly ash enhance the potential application.f.r the synthesis of zeolites for waste water treatment.

关键词： fly ash zeolite synthesis coal-fired power plant China

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匈牙利铝土矿的最佳化勘探

轻金属 1982年第7期 7-9+14页

作者： Antal füst 袁成荣

用分析法确定最佳钻孔数如果单个观测散布σ~2是已知的,并且平均值散布σ~2也是已知的或预先确定的,则所需要的观测次数n可用下式表达:

关键词：铝土矿床铝矿床网格稀疏钻孔间距双曲线关系参数变化匈牙利

Controllable synthesis of na P zeolite and its application in calcium adsorption

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Science China Materials 2015年第8期58卷 621-633,593页

作者： Ibraheem O.Ali Said M.El-Sheikh Tarek M.Salama Mostafa f.Bakr Mohamed H.fodial Department of Chemistry Faculty of Science Al-Azhar University nanostructured Materials Lab Advanced Materials Department Central Metallurgical R&D Institute (CMRDI)

naP zeolite particles were prepared through a template-free hydrothermal condition at 100oC. Parameters like na2O/Si O2 and Si O2/Al2O3 molar ratios, gel aging time and aging temperature were investigated for regulating the crystallization of the final product. The samples at different synthesis stages were characterized with n2 adsorption at-196oC, field emission scanning electron microscopy(fE-SEM), temperature programmed desorption of ammonia adsorption, X-ray diffraction, thermogravimetric and differential scanning calorimetry analysis and fourier tran.f.rm infrared spectroscopy. The experimental results evidenced that a high ordering crystallinity of na P zeolite was obtained at na2O/Si O2 and Si O2/Al2O3 molar ratios of 1.10 and 1.40, respectively, and a temperature of 100°C for 4 days of aging. fE-SEM image exhibited polycrystalline aggregates of na P zeolite with crystallite sizes ranging up to 5.04 μm with cactus/cabbage like structures. The quantitative analysis of the total number of acid sites was found to increase as na2 O increases. The na P zeolite sample with a na2O/Si O2 molar ratio of 1.13 exhibited a large fraction of the acid sites on its external surface, contrary to that synthesized with a relevant ratio of 1.10. The optimized na P zeolite could be successfully bestowed with excellent sorption properties of Ca(II) in aqueous solution. The kinetic parameters for Ca(II) adsorption were thoroughly investigated.

关键词：分子筛钙离子合成泡沸石凝血因子Ⅳ naP Al 摩尔比 Si

The Relationship between Dimensions of Emerging Adulthood and Behavioral Problems among Chinese Emerging Adults: The Mediating Role of Physical Activity and Self- Control

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International Journal of Mental Health Promotion 2023年第8期25卷 937-948页

作者： Jin Kuang Jeffrey Jensen Arnett Erle Chen Zsolt Demetrovics fabian Herold Rebecca Y.M.Cheung Daniel L.Hall Michaela Markwart Markus Gerber Sebastian Ludyga Arthur f.Kramer Liye Zou Body-Brain-Mind Laboratory School of PsychologyShenzhen UniversityShenzhen518060China Department of Psychology Clark UniversityWorcesterMA 01610USA Shenzhen College of International Education Shenzhen518172China Centre of Excellence in Responsible Gaming University of GibraltarGX111AAGibraltar Institute of Psychology ELTE Eötvös Loránd UniversityBudapest1239Hungary Research Group Degenerative and Chronic Diseases MovementFaculty of Health Sciences BrandenburgUniversity of PotsdamPotsdam14476Germany School of Psychology and Clinical Language Sciences University of ReadingReadingRG1UK Massachusetts General Hospital and Harvard Medical School Boston02115USA Department of Sport Exercise&HealthUniversity of BaselBasel4091Switzerland Center for Cognitive&Brain Health Northeastern UniversityBoston02115USA Beckman Institute University of IllinoisIllinois60001USA

Emerging adulthood(EA)is a critical stage of life to develop and sustain a healthy lifestyle,which is also a time of vulnerability to poor physical and mental health *** this study,we conducted a path analysis(n=1326)to examine associations among four dimensions of EA,levels of regular physical activity(PA),self-control,MPA tendency and irrational *** found:1)higher levels of PA predicted both MPA tendency(β=−0.08,95%CI:−0.11 to−0.06,pnd irrational procrastination(β=−0.01,95%CI:−0.17 to−0.008,pndirectly via self-control;2)Instability(β=0.13,95%CI:0.08 to 0.18,pnd Responsibility(β=−0.06,95%CI:−0.10 to−0.08,p=0.03)exerted direct effects on irrational procrastination and Instability also indirectly predicted irrational procrastination via MPA tendency(β=0.03,95%CI:0.02 to 0.05,pfindings proved that perceived features of EA are linked to behavioral problems and supported that regular PA plays a crucial role to protect mental health.

关键词： Emerging adulthood Chinese culture physical activity mobile phone addiction irrational procrastination self-control