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Optics and Photonics Journal 2019年第12期9卷 219-234页

作者： Pedro E. D. Cruz Tiago M. f. Alves Adolf. V. T. Cartaxo Instituto de Telecomunicações Lisboa Portugal Instituto Universitário de Lisboa (ISCTE-IUL) Lisboa Portugal

The perf.rmance of.the wavelength division multiplexing (WDM) photonic analogue-to-digital converter (ADC) used f.r digitization of.high-resolution radar systems is evaluated numerically by using the peak signal-to-noise ratio (SNR) metric. Two dif.erent WDM photonic ADC architectures are considered f.r the digitization of.radar signals with 5 GHz of.bandwidth (spatial resolution of.3 cm), in order to provide a comprehensive study of.the compromises present when deploying radar signals with high-resolution: 1) a f.ur-channel architecture with each channel employing an ADC with 5 GSamples/s, and 2) an eight-channel architecture with each channel employing an ADC with 2.5 GSamples/s. f.r peak powers of.the pulsed source between 10 and 20 dBm and a distance between the radar antenna and the sensing object of.2.4 meters, peak SNR levels between 29 and 39 dB are achieved with the eight-channel architecture, which shows higher peak SNR levels when compared with the f.ur-channel architecture. f.r the eight-channel architecture and f.r the same peak powers of.the pulsed source, peak SNR levels between 11 and 16 dB are obtained when the distance increases to 13.5 meters. With this evaluation using the peak SNR, it is possible to assess the perf.rmance limits when choosing a specif.c radar range, while keeping the same resolution.

关键词： Analogue-to-Digital Converter Radar Signal-to-Noise Ratio Wavelength Division Multiplexing

The Use of.PBL （Problem-Based Learning） in Improving the Student Perf.rmance in Navigation 3 （Terrestrial and Coastal Navigation）

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Journal of.Shipping and Ocean Engineering 2017年第4期7卷 161-167页

作者： Ma. Corazon S. NavallaseaI 2/M Mario B. Dumaicos 2/M Narciso f. Atanacio Bachelor of.Science in Marine Transportation (BSMT) Department John B. Lacson Foundation Maritime University-Arevalo Sto.Niho Sur Arevalo 1loilo City 5000 Philippines

这伪试验性的研究瞄准了调查 PBL 的有效性(基于问题的学习) 在改善 BSMT (在海洋的交通的理学士) 的在航行 3 的表演(陆上、沿海的航行) 在 JBLf.U-Arevalo 的第二个年学生在学年 2016-2017 的第一个学期期间。这研究的回答者是与在题... 详细信息

这伪试验性的研究瞄准了调查 PBL 的有效性(基于问题的学习) 在改善 BSMT (在海洋的交通的理学士) 的在航行 3 的表演(陆上、沿海的航行) 在 JBLf.U-Arevalo 的第二个年学生在学年 2016-2017 的第一个学期期间。这研究的回答者是与在题目航行 3 被注册的对方一起可比较的二节。有回答者们在试验性的组 30 使镇定下来的 60 学生， 30 在控制组织。A 验证了有 10 的做教师的解决问题测试削尖的三个项目因为每个正确答案被用作一台仪器。依赖变量是在航行 3 的分数，独立变量是 PBL 途径。使用的统计工具是平均数，标准差， Mann-Whitney 测试，和在意义的 0.05 水平设置的签名 Wilcoxon 的等级测试。效果尺寸被计算在航行 3 以学生性能决定 PBL 途径的有效性。尽管试验性的组比控制组，有一个更高的平均数，结果在预告测验显示出那因为重要价值比 0.05 大， Mann-Whitney 测试证明二个组的吝啬的分数是可比较的。当处理被介绍时，调查结果证明在在预告测验和 posttest 的航行 3 性能有重要差别试验性并且象在两个组的 posttests 一样的控制组。试验性的组的更好的表演能被归因于学生活跃地涉及学习过程的干预，这能被推断。

关键词：基于问题的学习陆上的航行沿海的航行伪试验性 JBLf.U-Arevalo。

Application of.Aquatic Plants f.r the Treatment of.Selenium-Rich Mining Wastewater and Production of.Renewable f.els and Petrochemicals

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Journal of.Sustainable Bioenergy Systems 2014年第1期4卷 97-112页

作者： Ana f. Miranda Nazim Muradov Amit Gujar Trevor Stevenson Dayanthi Nugegoda Andrew S. Ball Aidyn Mouradov Royal Melbourne Institute of.Technology University Melbourne Australia University of.Central f.orida Florida Solar Energy Centre Cocoa USA

Aquatic plants aggressively colonising wetlands are widely used f.r the biosorption of.the soluble contaminants f.om wastewater and represent an attractive f.edstock f.r biof.el production. Three common Australian aquatic plants, duckweed (Landoltia punctata), elodea, (Elodea canadensis) and water clover (Marsilea quadrif.lia), colonizing dif.erent depths of.wetlands were tested f.r their ability to treat the selenium-rich mining wastewater and f.r their potential f.r production of.petrochemicals. The results showed that these plants could be ef.ective at biof.ltration of.selenium and heavy metals f.om mining wastewater accumulating them in their f.st growing biomass. Along with production of.bio-gas and bio-solid components, pyrolysis of.these plants produced a range of.liquid petrochemicals including straight-chain C14-C20 alkanes, which can be directly used as a diesel f.el supplement or as a glycerine-f.ee component of.biodiesel. Other identif.ed bio-oil components can be converted into petrochemicals using existing techniques such as catalytic hydrodeoxygenation. A dual application of.aquatic plants f.r wastewater treatment and production of.value-added chemicals of.ers an ecologically f.iendly and cost-ef.ective solution f.r water pollution problems and renewable energy production.

关键词： Biof.el Bioremediation Pyrolysis Mining Wastewater Thermochemical Conversion

Updates in Orbital Tumors

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眼科学报 1993年第1期9卷 40-44页

作者： Nila f.Moeloek Department of.Ophthalmology University of.Indonesia Jakarta Indonesia

Orbital anatomy, the clinical f.atures of.orbital tumors, the recent development of.the diagnosis and management of.orbital tumors were described. The incidence of.orbital tumors in Dr. Cipto Mangunkusumo Hospital in ... 详细信息

关键词： diagnosis management orbital tumor

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Relationship between Cerebral Imaging and Executive f.nctions in Egyptian Elderly

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Advances in Aging Research 2014年第2期3卷 95-101页

作者： Motassem S. Amer Nagia A. f.hmy Sarah A. Hamza Eman f. Tash Mohammmad A. A. Allaboudy Department of.Geriatrics and Gerontology Faculty of Medicine Ain Shams University Cairo Egypt Department of.Neuropsychiatry Faculty of Medicine Ain Shams University Cairo Egypt

This study aimed at assessing the relationship between executive f.nctions and lef. sided hemiplegia due to non hemorrhagic supratentorial inf.rction in elderly Egyptians. It is considered a case control study which was conducted among 90 elderly participants, who were divided into two groups: a case group, 45 cases with cerebral inf.rctions of.6 months duration or more, and a control group who did not have previous cerebral inf.rctions. Both groups were selected f.om Ain shams University Hospital. Each participant was subjected to comprehensive geriatric assessment, executive f.nctions assessment using, block design test, digit span, letter verbal f.uency test, animal verbal f.uency test and clock drawing test, and then a Computed Tomography (CT) brain was perf.rmed. It was f.und that cases were suf.ering f.om more f.nctional impairment than controls, and have had signif.cant lower scores in Mini Mental Status Examination (MMSE) (P f.cant dif.erence was f.und between both groups as regards perf.rmance of.executive f.nction tests (P f.cant ef.ect of.Parietal lobe inf.rctions was f.und on Block Design Test, Digit Span Test, Animal Verbal f.uency and Clock Drawing Test (P value f.cant dif.erence between cases and controls as regards their perf.rmance in cognitive and executive f.nction tests.

关键词： Executive f.nctions Cerebral Inf.rctions Elderly

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近场测试中的计算机模拟方法

国外舰船技术.雷达与对抗类 1981年第5期 14-17页

作者： f.杰逊邵东

前言对天线性能的要求越来越高,相应地使得对天线测试的要求也越来越高。对于大型天线结构,近场测试技术是很有吸引力的,它比用一般远场测试所得到的精度要高一些。对设备容许误差的要求也更为严格。因此,重要的是能够设计出一种合理的... 详细信息

前言对天线性能的要求越来越高,相应地使得对天线测试的要求也越来越高。对于大型天线结构,近场测试技术是很有吸引力的,它比用一般远场测试所得到的精度要高一些。对设备容许误差的要求也更为严格。因此,重要的是能够设计出一种合理的测试设备,在设计中能

关键词：精度近场测试对数模式测试设备试验设备远场测试指数曲线机械系统线性模式

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卢卡奇遗著述评

世界哲学 1980年第3期 27-31页

作者： f.特克尔鸿雁匈牙利科学院教授哲学博士

当卢卡奇最后在1955年开始写作他的伟大著作《美学》时,他已经七十岁了。1962年他完成了第一部分。根据这位哲学家的计划,这一部分是从辩证唯物主义立场出发写成的,是他的《美学》的整个基础。实际上,这部著作不仅仅是对马克思主义认识... 详细信息

当卢卡奇最后在1955年开始写作他的伟大著作《美学》时,他已经七十岁了。1962年他完成了第一部分。根据这位哲学家的计划,这一部分是从辩证唯物主义立场出发写成的,是他的《美学》的整个基础。实际上,这部著作不仅仅是对马克思主义认识论的全新改造。卢卡奇把《美学》看成是他一生的主要著作,而它的读者也承认它是这样一部著作,把它看作是一位伟大思想家终生著作的最高荣誉。这部著作一下子结束了许多过去的讨论,并给这部书的作者带来了一种他从未得到过的承认。在他写完《美学》的其他部分之前,他下决心首先试图对社会存在的本体论作出马克思主义的改造。根据这部伟大的认识论著作,他已经深刻考虑到对认识论的研究不够充分,并试

关键词：卢卡奇社会存在本体论无机界辩证唯物主义辩证唯物论马克思主义哲学辩证法

Ef.ect of.natural organic matter on thallium and silver speciation

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Journal of.Environmental Sciences 2020年第7期32卷 185-192页

作者： Loïc A.Martin Caroline Simonucci Sétareh Rad Marc f.Benedetti Universitéde Paris Institut de physique du globe de ParisCNRSF-75005 ParisFrance IRSN PSE-ENV/SIRSE/LER-NordBP 1792262 Fontenay-aux-Roses CedexFrance Catchment and Eco-Hydrology Research Group Luxembourg Institute of Science and TechnologyL-4422 BelvauxLuxembourg BRGM Unitéde Géomicrobiologie et Monitoring Environnemental45060 Orléans Cedex 2France

Natural organic matter(NOM)is known to play an important role in the transport and binding of.trace metal elements in aquatic and soil *** is a pollutant f.r which the extent of.the role played by NOM is poorly ***,this study investigates thallium(Ⅰ)and its complexation to a purif.ed humic substance as proxy f.r *** were perf.rmed with the Donnan Membrane Technique to separate,f.r the f.rst time,the f.ee Tl^+ion f.om its complexed f.rm in the bulk *** pH and concentrations were investigated at constant ionic strength and constant NOM proxy concentrations in *** results were described with NICA-Donnan *** complexation was compared to silver complexation using literature data and using the same NICA-Donnan *** f.r these two cations(Tl^+and Ag^+)are reported in this article,f.r the f.rst *** display low thallium complexation to the NOM proxy while silver competes with divalent cations f.r the NOM binding *** speciation f.r dissolved thallium highlights the dominance of.f.ee thallium(Tl^+)in solution whereas Tl-NOM complexes contribute roughly 15%to total Tl(Ⅰ)species in river and lake type *** results are obtained f.r soil solutions,Tl-bound to NOMf.total,f.om UK soils with dif.erent land use and geochemistry.

关键词： Thallium Organic matter Speciation NICA-Donnan model Soil Water

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Trends of.Population Growth in China:Maximum Number Will Exceed 1.5 Billion

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China Population Today 1996年第1期13卷 16-17页

作者： f.Lin J Liu

ＴｒｅｎｄｓｏｆＰｏｐｕｌａｔｉｏｎＧｒｏｗｔｈｉｎＣｈｉｎａ：ＭａｘｉｍｕｍＮｕｍｂｅｒＷｉｌｌＥｘｃｅｅｄ１．５ＢｉｌｌｉｏｎⅠ．ＴｈｅＴｒｅｎｄｏｆＣｈｉｎａ＇ｓＰｏｐｕｌａｔｉｏｎＧｒｏｗｔｈａｔａＬｏｗＦｅ... 详细信息

ＴｒｅｎｄｓｏｆＰｏｐｕｌａｔｉｏｎＧｒｏｗｔｈｉｎＣｈｉｎａ：ＭａｘｉｍｕｍＮｕｍｂｅｒＷｉｌｌＥｘｃｅｅｄ１．５ＢｉｌｌｉｏｎⅠ．ＴｈｅＴｒｅｎｄｏｆＣｈｉｎａ＇ｓＰｏｐｕｌａｔｉｏｎＧｒｏｗｔｈａｔａＬｏｗＦｅｒｔｉｌｉｔｙＲａｔｅＴｈｅｍｏｓ...

关键词： Trends of.Population Growth in China

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Crambe (<i>Crambe abyssinica</i>) Cultivation under Dif.erent Levels of.f.rtilization with Nitrogen, Phosphorus and Potassium

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American Journal of.Plant Sciences 2017年第9期8卷 2031-2039页

作者： Ana Carolina f. de Vasconcelos Lúcia Helena G. Chaves Josely Dantas f.rnandes Gilvanise Alves Tito Department of.Agricultural Engineering Federal University of Campina Grande Paraiba State Brazil Department of.Agroecology and Agropecuaria State University of Paraiba Paraiba State Brazil

The ef.ects of.f.rtilization on crambe are poorly understood;in this sense, this study aimed to evaluate the crambe growth under dif.erent levels of.nitrogen (0, 40, 80, 120 kg·ha-1), phosphorus (0, 50, 100, 150 kg·ha-1), and potassium (0, 30, 60, 90 kg·ha-1) in a greenhouse. The height of.the plants, the production of.dried biomass and that of.1000 grains of.crambe were evaluated. The height of.the plants was impaired as a f.nction of.increasing doses of.nitrogen. The interaction of.nitrogen and phosphorus in the crambe crop increased the number of.grains and dry shoot biomass. The growth and yield of.the crop were not inf.uenced by the use of.potassium in mineral f.rtilization.

关键词： Biodiesel Semiarid Region Mineral f.rtilization Crambe Growth