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中国电化教育 2007年第1期 8-14页

作者： Mark van't Hooft 夏天美国肯特州立大学教育技术研究中心美国俄亥俄州44242 华东师范大学教育信息技术系上海200062

本文介绍了普适计算(Ubiquitous Computing)及其在教育中的定位,同时回顾了普适计算的历史,介绍了普适计算的发展现状,探讨了当前对教育中普适计算的理解及其对教学的影响。本研究阐述了范在学习条件下,教学、学习、学习环境和师生交互... 详细信息

本文介绍了普适计算(Ubiquitous Computing)及其在教育中的定位,同时回顾了普适计算的历史,介绍了普适计算的发展现状,探讨了当前对教育中普适计算的理解及其对教学的影响。本研究阐述了范在学习条件下,教学、学习、学习环境和师生交互发生的变化,也总结了普适计算在教育应用中的一些不足,并展望普适计算教育应用的未来。

关键词：普适计算移动设备因特网社会性软件工具教学学习

Reproductive performance of the Mesa silverside(Chirostoma jordani Woolman,1894)under natural and controlled photoperiods

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BIOCELL 2012年第3期36卷 105-111页

作者： JOSÉLUIS ARREDONDO-FIGUEROA LAURA GEORGINA NÚÑEZ-GARCÍA PALOMA ADRIANA HEREDIA-GUZMÁN JESÚS t.PONCE-PALAFOX Posta Zootécnica Departamento de ZootecniaCentro de Ciencias AgropecuariasUniversidad Autónoma de AguascalientesJesús MaríaAguascalientesMéxico Planta Experimental de Producción Acuícola Departamento de HidrobiologíaCBSUniversidad Autónoma Metropolitana IztapalapaMéxicoD.F Facultad de Estudios Superiores Iztacala Universidad Nacional Autónoma de MéxicoEstado de MéxicoMéxico Centro de Innovación y transferencia tecnológica CENItt Posgrado CBAPEscuela Nacional de Ingeniería PesqueraUniversidad Autónoma de NayaritTepicNayaritMéxico

Chirostoma jordani is a native annual species inhabiting lacustrine waters of the Central Mexico *** is widely distributed and is currently facing high environmental *** experi-ments were performed to study the reproductive performance of this *** of the experiments were conducted in 270-L indoor recirculation *** males and one female at the first stage of reproduction were included in each test.A photoperiod of 14 light hours and 10 dark hours was *** a fifth experiment,10 females and 15 males were kept in an outdoor 3,000-L recirculation tank under natural *** number of spawns,fertilised eggs and 30-day-old juveniles were counted and the survival rate was *** results indicated significant differences(Ptween *** spawn numbers and greater egg production were observed under controlled photoperiod,and higher numbers of juveniles and a higher survival rate were observed under natural *** trials exhibited different patterns of egg produc-tion during the *** egg production in the natural-photoperiod trials followed a polynomial curve *** contrast,the trials under the controlled photoperiod showed an irregular pattern of increases and decreases in egg production.

关键词： breeding Atherinopsidae eggs juveniles survival rate

Microstructure Investigation of (Y,Ce)-tZP-Al_(2)O_(3) Composite Materials

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Chemical Research in Chinese Universities 1993年第4期9卷 273-281页

作者： MENG Guang-yao YANG Ping-hua XU Qin-lun WANG Wei ZHANG Shu-yuan PENG Ding-kun Nakeda t. Department of Materials Science and Engineering Structure Research LaboratoryUniversity of Science&.Technology of ChinaHefei230026 Ibaraki Research Laboratory Hitachi Chemicals Co Ltd Japan

the microstructure of selected specimens in the(Y,Ce)-tZP-Al_(2)O_(3) composite systems was *** investigation techniques used in this work included X-ray diffractometry(XRD),Scanning Electroscope(SEM),transmission Electroscope(tEM),X-ray Energy Dispersion Analysis(EDAX)and High Resolution Electron Microscopy(HREM).Based on the experimental results,the relationship between microstructure and mechanical properties of the specimens was discussed.

关键词： Composite materials Mechanical properties Microstructure

Rare long-term survivors of pancreatic adenocarcinoma without curative resection

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World Journal of Gastroenterology 2015年第48期21卷 13574-13581页

作者： Stephen Y Oh Alicia Edwards Margaret t Mandelson Bruce Lin Russell Dorer W Scott Helton Richard A Kozarek Vincent J Picozzi Digestive Disease Institute Virginia Mason Medical Center Cancer Institute Virginia Mason Medical Center Department of Medical Oncology Virginia Mason Medical Center Department of Pathology Virginia Mason Medical Center Department of General Surgery Virginia Mason Medical Center

Long-term outcome data in pancreatic adenocarcinoma are predominantly based on surgical series, as resection is currently considered essential for longterm survival. In contrast, five-year survival in nonresected patients has rarely been reported. In this report, we examined the incidence and natural history of ≥ 5-year survivors with non-resected pancreatic adenocarcinoma. All patients with pancreatic adenocarcinoma who received oncologic therapy alone without surgery at our institution between 1995 and 2009 were identified. Non-resected ≥ 5-year survivors represented 2%(11/544) of all non-resected patients undergoing treatment for pancreatic adenocarcinoma, and 11%(11/98) of ≥ 5-year survivors. Nine patients had localized tumor and 2 metastatic disease at initial diagnosis. Disease progression occurred in 6 patients, and the local tumor bed was the most common site of progression. Six patients suffered from significant morbidities including recurrent cholangitis, second malignancy, malnutrition and bowel perforation. A rare subset of patients with pancreatic cancer achieve longterm survival without resection. Despite prolonged survival, morbidities unrelated to the primary cancer were frequently encountered and a close follow-up is warranted in these patients. Factors such as tumor biology and host immunity may play a key role in disease progression and survival.

关键词： Non-resected pancreatic cancer Long-termsurvival 5-year survival Chemotherapy Cholangitis Second malignancy Malnutrition

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华南上扬子区早-中奥陶世疑源类古环境意义

地层学杂志 2003年第4期27卷 298-305页

作者：李军 t.Servais 燕夔中国科学院南京地质古生物研究所江苏南京210008 法国里尔科技大学地球科学系

对上扬子区 7个剖面早—中奥陶世疑源类研究表明 ,这些疑源类组合在分异度及属种组成上呈现有规律的变化 ,这种变化是上扬子区古环境变化的反映。在上扬子区西部 ,近岸碎屑岩相沉积的滇东红石崖组所产疑源类组合分异度低 ,为个体较小、... 详细信息

对上扬子区 7个剖面早—中奥陶世疑源类研究表明 ,这些疑源类组合在分异度及属种组成上呈现有规律的变化 ,这种变化是上扬子区古环境变化的反映。在上扬子区西部 ,近岸碎屑岩相沉积的滇东红石崖组所产疑源类组合分异度低 ,为个体较小、壳饰较简单的分子 ;上扬子区中部 ,以黔北湄潭组为代表的浅海相碎屑岩和灰岩沉积中 ,疑源类分异度较高 ,并出现许多个体较大、壳饰较复杂的分子 ;而在上扬子区东部鄂西宜昌大湾组陆棚相灰岩与泥岩中 ,疑源类分异度继续增高 ,其中个体大、具粗大、长而复杂突起的分子占优势。

关键词：奥陶世疑源类古环境华南地区

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二十一世纪的逻辑与哲学

北京大学学报（哲学社会科学版） 2009年第1期46卷 45-54页

作者： t.威廉姆森牛津大学哲学系

冯赖特于1991年写道,逻辑学中大多数具有哲学意义的技术性工作似乎均已完成。本文作者以二阶逻辑、直觉主义逻辑、连续统值逻辑、一阶模态逻辑,以及关于绝对无限一般性的逻辑等等为例,说明逻辑学中大量具有哲学意义的技术性工作才刚刚... 详细信息

冯赖特于1991年写道,逻辑学中大多数具有哲学意义的技术性工作似乎均已完成。本文作者以二阶逻辑、直觉主义逻辑、连续统值逻辑、一阶模态逻辑,以及关于绝对无限一般性的逻辑等等为例,说明逻辑学中大量具有哲学意义的技术性工作才刚刚开始。对象语言中的非正统只有通过元语言的非正统才能得以充分探究与公正评价,这种非正统有时是关于逻辑的演绎力的,有时是关于语言的表达力的。两种类型的非正统导致在元逻辑研究方式上的争论。由于这方面工作的动机主要是哲学上的,而且所需要的技术常常具有哲学意味,这项工作必须由哲学家自己去完成。因此,在21世纪,逻辑学将继续受到哲学家的关注,哲学家也将继续对它的进一步发展做出贡献。

关键词：冯赖特元逻辑择代逻辑哲学争论

雅斯贝尔斯与海德格尔:关于哲学与政治的关系

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世界哲学 2013年第4期 125-138页

作者： t.罗克莫尔金寿铁美国匹兹堡杜肯大学哲学系吉林师范大学马克思主义学院吉林省社会科学院哲学与文化研究所

海德格尔与纳粹主义的关系一直是国际学术界争论的焦点话题。本文作者围绕雅斯贝尔斯《关于马丁·海德格尔的笔记》等著作,重新探讨了海德格尔前后思想与纳粹主义的内在关系。海德格尔与纳粹主义的亲合性并非是他校长任期以后就放弃了... 详细信息

海德格尔与纳粹主义的关系一直是国际学术界争论的焦点话题。本文作者围绕雅斯贝尔斯《关于马丁·海德格尔的笔记》等著作,重新探讨了海德格尔前后思想与纳粹主义的内在关系。海德格尔与纳粹主义的亲合性并非是他校长任期以后就放弃了的暂时的亲合性,而是自始至终都与其自身的哲学思想联系在一起的恒久的亲合性。不仅他的早期思想就坚信纳粹主义代表德意志民族的未来,他的后期思想也坚信想象中的纳粹主义代表德意志民族的未来。在与纳粹主义的深远而持续的联系中,海德格尔扮演了一种出卖理性、不负责任的角色。

关键词：雅斯贝尔斯海德格尔关于马丁·海德格尔的笔记海德格尔与纳粹的关系

Furrow design for improving crop establishment of two-wheel tractor operated strip tillage planters in loam and clay loam soils

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International Journal of Agricultural and Biological Engineering 2021年第3期14卷 130-139页

作者： M.Arshadul Hoque M.M.Hossain A.t.M.Ziauddin timothy J.Krupnik Mahesh K.Gathala Senior Scientific Officer FMP Engineering DivisionBangladesh Agricultural Research InstituteGazipur-1701Bangladesh Department of Farm Power and Machinery Bangladesh Agricultural UniversityMymensingh-2202Bangladesh International Maize and Wheat Improvement Center-Bangladesh Dhaka-1213Bangladesh

Conservation agriculture(CA)based production systems may help in achieving more sustainable intensification of cropping systems that use less labour and energy and have higher profit margins,in addition to soil conservation and environmental impact mitigation *** these objectives can only be achieved when the right mechanization options,including appropriate crop establishment equipment,are in place to assist in timely field *** urgent need exists,therefore,to fine tune and re-adjust the existing two-wheel tractor(2Wt)operated seed drills,with specific reference to the design of blade and furrow openers,while at the same time considering performance in different soil types and *** this end,experiments were conducted during 2013-2014 and 2014-2015 at two BARI Regional Agricultural Research Stations in Jamalpur and Barisal,Bangladesh,on a loam and clay loam soil,respectively,to evaluate five types of furrow opener for strip *** and modified shoe-type furrow openers were tested and compared with three inverted-t furrow openers with rake angles of 75°,65°and 55°.the newly designed inverted-t furrow openers were narrower than the shoe-type openers;they also had a longer,hollow shanks and provided better options for adjustment to achieve the desired seeding depth and line *** to shoe-type openers,better seeding depth,uniformity and higher degree of seed coverage were recorded with use of the inverted-t furrow opener with a 65°rake *** resulted in better seed coverage in the furrow,a higher emergence rate index,and the highest emergence percentage of maize and mung *** research findings can be generalized to smallholder production systems on loam and clay loam soils where farmers utilize 2Wt operated seed drills for crop establishment in both traditional and conservation agriculture-based planting systems.

关键词： two-wheel tractor strip tillage planter inverted-t furrow opener rake angle conservation agriculture emergence percentage

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偶次中立型泛函微分方程解的振荡性

应用数学和力学 2006年第10期27卷 1150-1158页

作者： t.卡丹海治尼代大学艺术和科学学院数学系

研究偶次中立型泛函微分方程,给出了该微分方程解的振荡性的充分条件.得到了一些新的结果并给出了一些示例.

关键词：中立型微分方程振荡分布偏差变量