简介：随着电子元器件的小型化，高集成度的发展，电子组装技术也经历了以下几个发展阶段，手工（50年代）——》半自动插装浸焊（60年代）——》全自动插装波峰焊（70年代）——》SMT（80年代）一》窄间距SMT（90年代）——》如今的超窄间距SMT。

简介：面对节省燃油和减排的要求．以及适应城市窄路的需要，哥斯达黎加设计师LuisVelazquez设计了一款城市汽车,命名为“RaptorV1（猛禽V1）”。

简介：Theproblemsoftheearth'sgravityfields'visualizationarebothfocusandpuzzlecurrently.Aimingatmultiresolutionrendering,modelingoftheEarth'sgravityfields'dataisdiscussedinthepaperbyusingLODalgorithmbasedonQuadTree.First,thispaperemployedthemethodofLODbasedonQuadTreetodivideuptheregionalgravityanomalydata,introducedthecombinednodeevaluationsystemthatwascomposedofviewpointrelatedandroughnessrelatedsystems,andtheneliminatedtheT-cracksthatappearedamongthegravityanomalydatagridswithdifferentresolutions.Thetestresultsdemonstratedthatthegravityanomalydatagrids'renderingeffectswereliving,andthecomputationalpowerwaslow.Therefore,theproposedalgorithmwasasuitablemethodformodelingthegravityanomalydataandhaspotentialapplicationsinvisualizationoftheearth'sgravityfields.

简介：AnewmethodisproposedforsurfaceconstructiononirregularquadmeshesasextensionstouniformB-splinesurfaces.Givenanumberofcontrolpoints,whichformaregularorirregularquadmesh,aweightfunctionisconstructedforeachcontrolpoint.TheweightfunctionisdefinedonalocaldomainandisC1continuous.Thenthewholesurfaceisconstructedbytheweightedcombinationofallthecontrolpoints.ThepropertyofthenewmethodisthatthesurfaceisdefinedbypiecewiseC1bi-cubicrationalparametricpolynomialwitheachquadface.ItisanextensiontouniformB-splinesurfacesinthesensethatitsdefinitionisananalogyoftheB-splinesurface,anditproducesauniformbi-cubicB-splinesurfaceifthecontrolmeshisaregularquadmesh.Examplesproducedbythenewmethodarealsoincluded.

简介：Inthispaper,anonlineardynamicMIMOmodelofa6-DOFunderactuatedquadrotorrotorcraftisderivedbasedonNewton-Eulerformalism.Thederivationcomprisesdeterminingequationsofmotionofthequadrotorinthreedimensionsandseekingtoapproximatetheactuationforcesthroughmodelingoftheaerodynamiccoefficientsandelectricmotordynamics.Thederivedmodelisdynamicallyunstable,soasequentialnonlinearcontrolstrategyisimplementedforthequadrotor.Thecontrolstrategyincludesexactfeedbacklinearizationtechnique,usingthegeometricmethodsofnonlinearcontrol.Theperformanceofthenonlinearcontrolalgorithmisevaluatedusingsimulationandtheresultsshowtheeffectivenessoftheproposedcontrolstrategyforthequadrotorrotorcraftnearquasi-stationaryflight.

简介：9月11—13日期间，英国老牌Hi—Fi厂商QUAD带了一系列最新型号器材和顶级旗舰现场开声展示，包括ESL静电系列扬声器，最新一体机Vena，S系列新音箱等，从外观到内部配置都有很大变化，表示QUAD紧跟潮流持续发展。

简介：AbstractPurpose:There are many infectious and inflammatory causes for elevated core-body temperatures, though they rarely pass 40 ℃ (104 ℉). The term "quad fever" is used for extreme hyperpyrexia in the setting of acute cervical spinal cord injuries (SCIs). The traditional methods of treating hyperpyrexia are often ineffective and reported morbidity and mortality rates approach 100%. This study aims to identify the incidence of elevated temperatures in SCIs at our institution and assess the effectiveness of using a non-invasive dry water temperature management system as a treatment modality with mortality.Methods:A retrospective analysis of acute SCI patients requiring surgical intensive care unit admission who experienced fevers ≥ 40 ℃ (104 ℉) were compared to patients with maximum temperatures < 40 ℃. Patients ≥18 years old who sustained an acute traumatic SCI were included in this study. Patients who expired in the emergency department; had a SCI without radiologic abnormality; had neuropraxia; were admitted to any location other than the surgical intensive care unit; or had positive blood cultures were excluded. SAS 9.4 was used to conduct statistical analysis.Results:Over the 9-year study period, 35 patients were admitted to the surgical intensive care unit with a verified SCI. Seven patients experienced maximum temperatures of ≥ 40 ℃. Six of those patients were treated with the dry water temperature management system with an overall mortality of 57.1% in this subgroup. The mortality rate for the 28 patients who experienced a maximum temperature of ≤ 40 ℃ was 21.4% (p = 0.16).Conclusion:The diagnosis of quad fever should be considered in patients with cervical SCI in the presence of hyperthermia. In this study, there was no significant difference in mortality between quad fever patients treated with a dry water temperature management system versus SCI patients without quad fever. The early use of a dry water temperature management system appears to decrease the mortality rate of quad fever.

简介：平均深度的流动污染物质联合了的A2D模型基于空铅树网孔被建立精确地在这篇论文与不规则的自然边界在水区域模仿流动。格子被递归的分关于播种点产生。一个发现newneighbor算法被介绍。管理方程是在由越过在房间之间的接口使用有限的卷方法，和质量，动量和污染物质的正常流动的并置的保守变量的discretized被一个Godunov类型流动DifferenceSplitting(FDS)计划计算。模型被使用在一条腹股沟附近模仿流动地。计算的值与观察数据一致。结果显示空铅树网孔有好本地分辨率，高效率和容易的本地精炼。当适用于复杂流动领域时，空铅树格子模型能在效率提供获得，是清楚的或强壮砍流动。最后，模型在江苏HaizhouBay被用于流动地和集中地模拟。模仿的弄脏的区域与观察被匹配很好。因此，这个模型能被用来与不规则的自然土地边界预言实际的水区域的流动和集中地。

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简介：在英国伦敦，每当夜幕降临，约近十万人会来到音乐厅、歌舞厅，就一座城市而言，这个数字意味着什么样的概念呢，我想，绝对不是一个量的关系，它代表了一个民族整体的文化素质、音乐涵养、艺术情操。那么，在这样一个国度设计生产的音响器械，必然隐藏着原始积累的元素，厚积而薄发，这种与生俱来的气质就是他们产品的价值。当我们今天接触英国许多音响器材：君子、莲、音乐传真、英国之宝的产品，诚然体会到一种博大而深厚的文化底蕴和格调高雅的美。近期，依然来自英伦的QCAD99系列，更是带着多姿的人文色彩进入我们的视野，亦是本文将要介绍的主角。

简介：今年是英国Wharfedale（乐富豪）建厂75周年，Wharfedale的中国总代理深圳“沃夫德尔公司”于12月初广州白天鹅“2007广州音响唱片展”结束后，将假座深圳“IAG乡村俱乐部”和“聚豪高尔夫俱乐部”

简介：在北方大雪纷飞的时候，广州也好不到哪里去，据说体感温度都赶上北京了。没有暖气的广州，抗寒只能靠抖，严寒之下人的思维仿佛就要停滞，工作效率只能呵呵。遇到寒冷的冬天，音Ⅱ向发烧友第一时间肯定会想到胆机，虽然没有实际的御寒效果，但看着都暖。说到御寒好去处，笔者一下子就想到音响店，那里不但温暖，还有音乐可以欣赏，碰上热情的商家，还给你奉上热茶，前提是你跟店家很熟。