美国超级房车赛新秀Kahne感到压力

2004赛季的新秀Kahne日前承认，他对自己在2005赛季最后几场的表现不很满意。当然，他在Richmond赢得了他的首个分站优胜，但是他描述他的上赛季似乎有些惨。

Wells评分、Kahn评分、St. André评分、Constans评分对下肢深静脉血栓的诊断价值研究

目的评价Wells评分、Kahn评分、St.André评分、Constans评分对下肢深静脉血栓(DVT)的诊断价值。方法选择2006年7月—2009年3月在宁夏医科大学总医院行直接CT静脉造影(CTV)、间接CTV、下肢B超检查的疑诊DVT的住院患者278例,分别行下肢Wells评分、Kahn评分、St.André评分、Constans评分。以各评分低度可能DVT作为阴性结果,中度可能DVT和高度可能DVT作为阳性结果;以CTV检查和/或下肢B超作为诊断DVT的金标准,分别计算各评分诊断DVT的灵敏度、特异度、阳性预测值、阴性预测值和ROC曲线下面积(AUC)。结果各评分诊断DVT的灵敏度、特异度、阳性预测值、阴性预测值、AUC,Wells评分为92.3%、48.9%、65.7%、85.7%、0.845;Kahn评分为64.3%、29.6%、49.2%、44.0%、0.526;St.André评分为90.2%、51.8%、66.5%、83.3%、0.761;Constans评分为95.8%、23.0%、56.8%、83.8%、0.755。Z检验结果显示,除St.André评分与Constans评分诊断DVT的AUC差异无统计学意义外,其他评分两两比较,差异均有统计学意义(P<0.05)。结论通过比较Wells评分、Kahn评分、St.André评分、Constans评分对DVT的诊断价值发现,Wells评分在4种评分中诊断效能最高,比较适用于中国人群。

固溶处理对7A55铝合金断裂韧性的影响

采用金相组织观察、拉伸实验、Kahn撕裂试验、扫描电镜、透射电镜等方法研究固溶处理对7A55铝合金断裂韧性的影响。研究结果表明:固溶温度对7A55铝合金断裂韧性影响显著,7A55铝合金在450～490℃时固溶,随着温度上升,可溶性粒子减少,断裂韧性增加,到480℃时断裂韧性达到最大值;当温度超过480℃时,由于晶粒的长大,断裂韧性又开始下降;7A55铝合金有很大的淬火敏感性,当以慢速淬火时,晶界非共格析出物尺寸粗大,对断裂韧性不利。

7055铝合金二次时效特征研究——(I)力学性能

利用维氏硬度和拉伸力学性能测试、Kahn撕裂试验等方法,研究二次时效对7055铝合金力学性能的影响。结果表明,经过120℃,150℃和180℃高温欠时效,甚至峰值时效处理后,再进行60℃和100℃低温二次时效,可以获得超过相应单级峰值时效的硬度和强度。Kahn撕裂试验表明,二次时效温度从60℃提高到100℃,可以缩短二次峰值硬化时间,但不利于7055铝合金断裂韧性的改善。在相同预时效温度下,缩短预时效时间比峰值时效状态更有利于断裂韧性的改善。较低预时效和二次时效温度以及较短预时效时间有利于获得强度和断裂韧性的良好配合。

高强度热冲压钢板强韧性工艺优化研究

为改善强韧性，本文基于热冲压高强度钢板强度、塑性和韧性指标，选取加热温度、保温时间和开始淬火温度为设计因子，引入Kahn试验获得高强度热冲压硼钢撕裂强度和单位面积裂纹形核功来表征材料断裂韧性，进行多指标综合评分的L9（3^4）正交试验设计，以研究不同淬火工艺参数对热冲压高强钢强韧性的影响规律．结果表明：在加热温度为920～950℃、保温时间1min、开始淬火温度为650～700℃条件下，热冲压硼钢SPFH具有优良的成形性能和强韧化指标．采用优化后工艺进行典型车身结构件热冲压试验，其撕裂强度、单位面积裂纹形核功和强韧比分别提升10．91％、20．32％和22．17％，在保证强度的基础上韧性得到了大幅度提高．

轧制变形量对Al-5Zn-3Mg-1Cu合金显微组织和力学性能的影响

采用室温拉伸试验、Kahn撕裂试验,结合光学显微镜、透射电子显微镜等方法,研究了Al-5Zn-3Mg-1Cu铝合金厚板在热轧过程中随轧制变形量增大其合金组织和力学性能的演变过程.结果表明:热轧变形过程中,变形量从56%增大至91%时,合金的再结晶分数由0.49%增大至43.30%,晶粒尺寸从83μm减小至10μm以下,合金的抗拉强度和屈服强度分别从542.3和520.0 MPa提升到593.4和564.9 MPa,延伸率从8.0%左右提高到11.2%;随轧制变形量的增大,合金撕裂强度和单位面积裂纹形核功呈增大的趋势.

中国资本管制有效性动态研究:1982-2008

文章综合利用储蓄—投资相关性检验法、Edwards-Kahn模型法、资本管制强度测度以及抵补利率平价4种方法分别从实体经济、货币经济、法律框架以及短期资本套利动机等角度对1982-2008年期间我国资本管制的有效性进行了评估,并侧重讨论了现阶段我国资本管制是否失效的问题。研究结论显示:自1982年以来,我国的资本管制政策短期内基本有效,但随着国内经济的进一步开放和管制政策的逐步放开,资本流动性逐渐提高,资本管制的有效性呈下降趋势;2007年以来虽然存在大量短期资本流入流出的现象,但我国的资本管制仍然对国际资本流动具有明显的抑制作用。

分布式Kahn处理网络的一种集群调度算法

研究并提出一种采用分布式Kahn处理网络表达的并行程序在多处理器集群环境下的任务———处理器动态分配算法。由于Kahn处理网络的不可判定性,静态作业调度算法不能适用,而忽略其显式数据依赖关系的动态负载均衡策略存在很大的随机性,往往带来不必要的进程迁移。基于运行时动态生成的离散事件序列,预测Kahn处理网络在不同分配方案下的执行效率(处理器资源利用率),迭代寻求最优动态分配方案,仿真效果良好。

CSCE:一个协同的服务组装支持环境

呈现了一个基于KPN(kahn process network)的服务协同组装支持环境(CSCE)。KPN是一个基于数据流的协同计算模型,用于描述通过数据流进行通信的一系列协作过程。在CSCE协同组装环境中,KPN用于建模服务及服务之间的动态交互,为应用系统的组装提供可视化的用户接口。将KPN应用于服务组装,目的是减少服务组装的不可预见性,提高服务组装的成功率。介绍了基于KPN的服务组装基本思想,给出了CSCE的体系结构,详细描述了CSCE各协作部件的基本功能。

T6I6时效对7050铝合金性能的影响

采用维氏硬度测试、电导率测试和拉伸、Kahn撕裂试验及扫描电镜断口形貌观察等方法,研究了T6I6时效对7050铝合金的性能与断口形貌的影响。结果表明,与T6峰值时效相比,经T6I6时效,7050铝合金的强度、硬度和电导率基本保持不变;经120℃×15min+60℃×720h+120℃×23.75h处理,伸长率提高53.2%;经120℃×30min+60℃×24h+120℃×23.5h处理,撕裂强度和单位形核功较T6峰值时效分别提高21.3%和57.8%;T6I6时效的撕裂试样断口为韧窝型穿晶断口,而经T6处理后,合金断口为沿晶脆性断裂和少量穿晶韧窝混合型断口。

Simon Kahn:多屏移动营销大趋势

在亚洲,包括中国,消费者现在都生活在移动连接的世界里,日复一日地使用移动终端购买商品,移动互联网趋势越来越明显。例如,两年前的中国,桌面终端和移动终端使用数字的差距还没有显现出来;现在,无论是欧美还是包括中国在内的亚洲国家,消费者通过移动终端购买的比例已超过桌面终端。从消费者的角度看,购物行为的最大变化就是通过移动终端购买;从商家的角度看,他们要考虑消费者使用移动终端对他们的业务产生什么影响,对消费者的购买决策有什么影响。Google的数据表明,91%的中国消费者通过各种移动终端搜索要买的东西,至少超过一半的消费者通过移动终端购买。由此可见,移动终端蕴含着巨大的商机。

私有化并购下商业判断规则的创新适用——以Kahn v.M&F Worldwide Corp案为例

案件源于2011年的一起公司收购案,收购方为MacAndrews&Forbes Holdings公司(以下简称M&F公司),其拥有被收购方M&F Worldwide公司(以下简称MFW公司)43%的普通股份。2011年6月,Schwartz(Schwartz同时为MFW公司的总裁和首席执行官和M&F公司的副总裁和首席行政官)向MFW发出了收购要约.

Ned Kahn：以景观设计展现自然的力量

Ned Kahn是一位景观设计师，他的设计灵感源自各种自然现象，如风、水、火、雾、沙等，他运用大胆而细致的设计手法，将这些元素，通过雕塑和大型的装置艺术，带到公众面前。他的景观设计作品非常直观，有时亦很平实，相信读者看过之后，都能从中感受到自然的力量。正如Ned Kahn本人所说，“我希望我的艺术品，能让人们记起大自然的美丽与神秘，希望人们在看到这些自然现象发生时，能产生一种对自然的敬畏之感，同时也点燃他们对大自然的热爱之情。”

Exploring the Far Side of Glycosyl Sulfoxide Activation Process

The discovery of Kahne glycosylation forwards a big step in the carbohydrate chemistry.Despite an extensive series of studies,the precise mechanism of this powerful glycosylation is still not fully understood.To address these 30-year puzzles,the far side of Kahne glycosylation is explored in this study.After a series of control and tracking experiments,a number of important intermediates including glycosyl oxo-sulfonium ion and sulfenic anhydride(Crich's intermediate)are suggested to be responsible for the complex reaction pathway.It also reveals that in addition to the conventional ionic glycosylation pathway,a novel free radical pathway is very likely to contribute to the various side-and co-products.This study provides further understanding of Kahne glycosylation,and it also sheds light on how to improve the efficiency of sulfoxide-based glycosylation reactions.

Ce对Al-Li-Cu-Mg-Ag-Zr合金断裂性能的影响

通过拉伸力学性能测试、Kahn撕裂法研究了Ce对Al-Li-Cu-Mg-Ag-Zr合金力学性能的影响,同时利用金相显微镜(OM)、扫描电镜(SEM)、透射电镜(TEM)对合金组织和断口形貌进行了分析,结果表明:合金在180℃下时效后,Ce元素的加入显著提高了合金的强度、塑性及Kahn撕裂韧性.金相显微观察发现:含Ce合金中铸态晶粒细化明显,固溶处理过程中,Ce原子明显抑制了再结晶晶粒的长大,同时在长横方向保留了大量冷加工的纤维组织.Ce的加入使晶界无析出带变窄.并促使了韧窝断裂的发生.

Optimization Evaluation Test of Strength and Toughness Parameters for Hot-Stamped High Strength Steels

Use of hot-stamped high strength steels （HSHSS） not only reduces the vehicle weight, but also improves the crash safety, therefore more and more mentioned steels are used to produce automobile parts. However, there are several problems especially the low ductility and toughness, which have restricted the application of HSHSS in automobile body. Suitable process parameters are very crucial to improve strength and toughness. In order to study the effect of austenization temperature, soaking time and start deformation temperature on strength and toughness of boron steel 22MnB5, an L9 （34） orthogonal experiment which was analyzed by means of comprehensive evaluation was carried out based on Kahn tear method to obtain the value of fracture toughness. The results indicate that the ex- cellent formability, high strength and toughness of boron steel 22MnB5 with 1.6 mm in thickness are obtained when the austenization temperature is in the range of 920- 950 ℃, the soaking time is 1 min and the start deformation temperature is in the range of 650- 700 ℃. The optimal parameters were used for typical hot stamping structural parts tests. Properties of samples such as tear strength, unit initiation energy and ratio of strength to toughness （RST） were improved by 10.91%, 20.32% and 22.17%, respectively. Toughness was increased substantially on the basis of a small decrease of strength.

Reinforced concrete in Louis Kahn＇s National Assembly, Dhaka： Modernity and modernism in Bangladeshi architecture

Louis Kahn is often credited with having in his introduced modern architecture to Bangladesh. In construction as any he employed was already in National Assembly in Dhaka （1962-1983） fact at least as technologically advanced use there. Nor was he the first to use a sophisticated abstract esthetic in what was from 1947 to 1971 East Pakistan. The importance and originality of the National Assembly instead resides in the care with which he built in reinforced concrete and the forms into which he required that it be cast. These were esthetic decisions rooted in a particular theoretical position; they were located outside established modernist practice of the time in both South Asia and the United States. Indeed operating at such a great remove from home may have heightened Kahn＇s authority to implement these forms even as it substantially complicated their execution.

Kahn’s light:The measurable and the unmeasurable of the Bangladesh National Assembly Building

To incline and unfold the constituent elements of Louis I.Kahn’s architecture and philosophy,a precise attention must lie on the fundamental objectives that he vigorously pursued and mastered,especially in his latest works.This work focuses attention on Louis Kahn’s idiosyncratic approach to light manipulation which he used to shape his architecture.That’s due to the constant coherence of his approach even today.As we are merged in the plurality of fonts that haul our discipline,we constantly question the real sense of architecture and what makes it intelligible.Kahn’s method drew conclusions and seeked for this sense through precise fonts:lessons from the past,current modernist flow,and the context.He combined and transformed these inspirations distinctively through his own sensitivity to achieve that spiritual value and its own true sense that architecture should retain in its form.Thus,it is considered of utmost interest to rethink his approach and particularly to reflect today on the pertinence of his main architectural parameter:Light.

Two Studies Carried out in the SPURS Program

The SPURS program in MIT provides an encouraging environment for fellows to carry out studies on a wide range of topics. In this essay, I briefly describe the two research works I finished as part of SPURS in 2016. One of them originated from the shared interest in affordable housing among SPURS fellows. The other one came from a combination of urban study with my previous study on architectural history and theory. Besides a short description of the contents and conclusions of these projects, this essay also illustrates the positive impacts the SPURS program made on my current work and studies.

C．Ronald Kahn访谈 胰岛素与糖尿病

自1921年一个位于多伦多（Toronto）的实验室发现胰岛素以来的大半个世纪过去了，医学研究领域对胰岛素的认识曾仅限于它是糖尿病中缺少的激素。但实际上胰岛素的作用是很多的，研究人员一直试图了解这一切。胰岛素是脂肪和碳水化合物代谢的主要调节者，并且还控制着这些营养物质的储存。在人体细胞中，它刺激与细胞功能和生长有关的分子的合成，以及细胞内蛋白质甚至RNA和DNA分子的合成。