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ONGs brasileiras em Boston
Teresa, Sales;
Estudos Avan?ados , 2006, DOI: 10.1590/S0103-40142006000200007
Abstract: this essay examines how brazilian immigrants in the metropolitan region of boston, usa, are becoming increasingly organized. based on an october 2005 survey, it lists the various organizations created by brazilian immigrants from 1995 to 2005 in framingham, boston, somerville, and cambridge. the conclusion is that brazilians have advanced more in terms of political organization (because of the cultural baggage some leaders brought from brazil) than in the service industry.
The Naive versus the Adaptive Boston Mechanism  [PDF]
Timo Mennle,Sven Seuken
Computer Science , 2014,
Abstract: The Boston mechanism is often criticized for its manipulability and the resulting negative implications for welfare and fairness. Nonetheless, it is one of the most popular school choice mechanisms used in practice. In this paper, we first study the traditional (naive) Boston mechanism (NBM) in a setting with no priority structure and single uniform tie-breaking. We show that it imperfectly rank dominates the strategyproof Random Serial Dictatorship (RSD). We then formalize an adaptive variant of the Boston mechanism (ABM), which is also sometimes used in practice. We show that ABM has significantly better incentive properties than NBM (it is partially strategyproof), while it shares most of NBM's efficiency advantages over RSD as markets get large. However, while a direct efficiency comparison of NBM and ABM via imperfect dominance is inconclusive, numerical simulations suggest that NBM is still somewhat more efficient than ABM, which can be interpreted as the cost of partial strategyproofness one pays when choosing ABM over NBM. Our results highlight the subtle trade-off between efficiency and strategyproofness a market designer must make when choosing between the two Boston mechanisms and RSD.
Completing the Results of the 2013 Boston Marathon  [PDF]
Dorit Hammerling, Matthew Cefalu, Jessi Cisewski, Francesca Dominici, Giovanni Parmigiani, Charles Paulson, Richard L. Smith
PLOS ONE , 2014, DOI: 10.1371/journal.pone.0093800
Abstract: The 2013 Boston marathon was disrupted by two bombs placed near the finish line. The bombs resulted in three deaths and several hundred injuries. Of lesser concern, in the immediate aftermath, was the fact that nearly 6,000 runners failed to finish the race. We were approached by the marathon's organizers, the Boston Athletic Association (BAA), and asked to recommend a procedure for projecting finish times for the runners who could not complete the race. With assistance from the BAA, we created a dataset consisting of all the runners in the 2013 race who reached the halfway point but failed to finish, as well as all runners from the 2010 and 2011 Boston marathons. The data consist of split times from each of the 5 km sections of the course, as well as the final 2.2 km (from 40 km to the finish). The statistical objective is to predict the missing split times for the runners who failed to finish in 2013. We set this problem in the context of the matrix completion problem, examples of which include imputing missing data in DNA microarray experiments, and the Netflix prize problem. We propose five prediction methods and create a validation dataset to measure their performance by mean squared error and other measures. The best method used local regression based on a K-nearest-neighbors algorithm (KNN method), though several other methods produced results of similar quality. We show how the results were used to create projected times for the 2013 runners and discuss potential for future application of the same methodology. We present the whole project as an example of reproducible research, in that we are able to make the full data and all the algorithms we have used publicly available, which may facilitate future research extending the methods or proposing completely different approaches.
Infectious keratitis in patients undergoing Boston Type 1 keratoprosthesis (Boston KPro) procedure: case series
Nascimento, Heloisa Moraes do;Oliveira, Lauro Augusto de;H?fling-Lima, Ana Luisa;
Arquivos Brasileiros de Oftalmologia , 2011, DOI: 10.1590/S0004-27492011000200012
Abstract: description of two cases of infectious keratitis in patients after boston type 1 keratoprosthesis (boston kpro) implantation. the first case refers to a patient that had the device indicated due to limbal deficiency secondary to severe dry eye who presented a fungal infection by aerobasidium pullulans that was successfully treated with amphotericin b eye drops. the second case reports a patient with boston kpro implantation due to previous corneal transplant rejection showing bacterial keratitis in the fourth postoperative month. the etiologic agent was identified asstreptococcus sp and topical treatment with vancomycin was effective. the importance of postoperative surveillance in boston kpro eyes is discussed.
响叶杨(populusadenopoda)种子的形成及其寿命  [PDF]
吴琼美,樊汝汶
南京林业大学学报(自然科学版) , 1984, DOI: 10.3969/j.jssn.1000-2006.1984.01.014
Abstract: <正>用显微技术及软x射线摄影,定位观察响叶杨种子发育过程中的形态变化与胚胎发育的对应关系。根据观察、试验的结果,讨论了环境条件与种子寿命的关系;还测定了响叶杨种子寿命的变化规律及其影响因素,探索延长这种子寿命的方法。
响蜜Lie科的新记录
杨岚
动物学研究 , 1995,
Abstract: 1994年10月15日马中翼等人在云南省泸水县的老窝捕获到1只雄鸟,经中国科学院昆明动物研究所鉴定为黄腰响蜜lie,为我国鸟类科的新记录。标本保存在中国科学院昆明动物研究所鸟类标本室。科的特征体形较小。嘴形似雀,短而粗实,上嘴稍弯曲;尾羽12枚;翅形长而尖,仅具9枚初级飞羽;脚呈对趾型,第2、3趾向前,第1、4趾向后,似啄木鸟。
响蜜lie科的新记录  [PDF]
动物学研究 , 1995,
Abstract: 1994年10月15日马中翼等人在云南省泸水县的老窝捕获到1只雄鸟,经中国科学院昆明动物研究所鉴定为黄腰响蜜lie,为我国鸟类科的新记录。标本保存在中国科学院昆明动物研究所鸟类标本室。科的特征体形较小。嘴形似雀,短而粗实,上嘴稍弯曲;尾羽12枚;翅形长而尖,仅具9枚初级飞羽;脚呈对趾型,第2、3趾向前,第1、4趾向后,似啄木鸟。
乳牛房的清晨  [PDF]
华南农业大学学报 , 1959,
Abstract: 清晨,大阳刚Nl]东升,乳牛粗的工友和同学,就在牛房内外忙开了。夜班的同志忙了一整夜,依旧要和日班的战友多干一会儿。你拿扫帚,我洒洒石灰,一会儿功夫,牛栏里再没有阂料的竣渣和粪尿。地板复卜乳白色的灰浆。坡璃窗和物壁显得光亮耀眼。夙填的蛛网一扫而光。乳牛嘟着新添的甸料,摇头摆尾威谢它的主人。…||以乳牛房的清晨@包世增~~
液压减振器液压模型与气穴异响研究  [PDF]
罗天洪,金锐超,江礁,胡启国,朱孙科
重庆交通大学学报(自然科学版) , 2014, DOI: 10.3969/j.issn.1674-0696.2014.01.34
Abstract: :?为了降低液压减振器气穴异响,分析了压缩和复原过程中液压油的运动状态和气穴的生成过程,建立了气穴系数与节流孔直径之间的关系模型,以及双筒液压减振器的参数模型;通过Simulink对液压减振器压缩和复原过程的仿真分析,确定了减振器气穴异响与节流孔直径和油液运动黏度的关系。结果表明:减振器的异响可以通过增加节流阀的有效节流直径和降低油液运动黏度来减轻。
汽车发动机异响模糊诊断  [PDF]
闵永军,黄银娣,万茂松,黄?先
南京林业大学学报(自然科学版) , 1998, DOI: 10.3969/j.jssn.1000-2006.1998.02.005
Abstract: <正>论述了基于模糊数学理论的汽车发动机异响模糊诊断方法,提出了模糊诊断数学模型、模糊关系矩阵的建立方法及模糊推理诊断过程。据此建立的汽车故障诊断专家系统,提高了对发动机异响故障诊断的准确性和可信度。
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