微笑住宅

由BIG建筑事务所设计的"微笑住宅"坐落于纽约市哈林街.它毗邻城市活跃街区,是一座可提供经济适用房的多功能混合型住宅. 1912年,曼哈顿下城的Equitable大楼以极度贴合街区的范围和尺度被建造.其笔直的形态高耸入天,给人以强大的压迫感.自那时起,该栋建筑便被视为开发商的建造典范,并促使美国首部建筑法规诞生.这一具有地标地位的建筑于1916年被当地建筑法案强制以"阶梯形立面"形式进行改造,以满足街区生活对于光照和通风的需求.此次BIG建筑事务所以曲面设计诠释了对该栋建筑的全新理解,通过悬挑搭建和弯曲避让,微笑住宅得以用谦让的姿态栖息于场地,令哈莱姆街区焕然新生.     

打造"梦想城市"——丹麦馆

1工程概况 2010年上海世博会丹麦馆以"梦想城市"为主题,著名的小美人鱼雕像倚坐在代表哥本哈根海湾的展馆水池中央.围绕着水池的是一个上下盘旋的环状箱体建筑物,建筑物的楼面和屋面,分别构成了室内、室外两个互相连通且绵延不断的连续螺旋形通道,建筑面积约为3000m2.参观者既可漫步其中,观赏展示丹麦人民生活的展览,也可骑着绿色交通工具--自行车穿梭其间,体会丹麦馆"梦想城市"的感觉.     

Direct digital-RF amplitude modulator in CMOS 90nm

Two different wireless transmitter topologies based on an direct digital-RF amplitude modulator (DAM) are presented: a polar modulator and a direct digital-RF IQ modulator prototype. The DAM consists of 255 basic cells digitally activated by an 8-bit amplitude code to shape a non-constant envelope RF output. The cells are segment-addressed resulting in a very compact 0.007 mm² chip area in CMOS 90nm. In order to reduce the spectral images due to the discrete-time to continuous-time conversion a 2-fold interpolation has been implemented. The DAM reaches a peak output power of 5 dBm at 2.45 GHz with 23% drain efficiency. Both direct digital modulator architectures fulfill WLAN 802.11g linearity constrains at 2.45 GHz.     

Design strategies and decoupling techniques for reducing theeffects of electrical interference in mixed-mode IC's

A key issue in the successful integration of analog circuits is a stable analog power supply. Traditional on-chip decoupling methods exhibit transients in the supply or voltage drops and power losses. This paper introduces the RLC decoupling method that features an enhanced transient response while being especially suited for low-power, low voltage applications. Both a theoretical and a practical approach are presented together with measurement results. As the benefits of a stable local power supply can be lost by the inadequate connection of two subcircuits with relative variations on the local grounds, a differential approach of signal transfer is proposed. Furthermore, the effect of a good local decoupling can be deteriorated by substrate noise, so some attention is given to this problem too     

Complete unloading alone may not adequately protect the left ventricle

BACKGROUND: The benefit of left ventricular (LV) unloading for preserving LV function is commonly accepted, but its efficacy remains incompletely defined. METHODS: We studied the influence of complete LV unloading on LV systolic and diastolic mechanics using an in situ isovolumic preparation with two different coronary perfusion pressures (CPPs) in 12 dogs during prolonged normothermic cardiopulmonary bypass. RESULTS: Multivariate analysis of covariance with time as a covariate revealed that a high CPP (143 +/- 36 mm Hg; n = 6) was associated with better preservation of systolic LV function over time as assessed by LV end-systolic elastance (p < 0.001) and the end-systolic pressure-volume relation physiologic intercept (p < 0.001) compared with a moderate CPP (107 +/- 18 mm Hg; p < 0.005 versus a high CPP by t-test; n = 6). Dobutamine (2 micrograms.kg-1.min-1) improved LV end-systolic elastance (p < 0.005) and LV physiologic intercept (p < 0.01) only in the high-CPP group. Conversely, impaired LV diastolic function (as measured by LV stiffness) was observed (p < 0.001) with a high CPP, but did not change with a moderate CPP. CONCLUSIONS: These observations in canine hearts suggest that complete LV unloading may not preserve LV systolic function adequately over time when CPP is maintained in the accepted clinical range. A higher CPP is required to prevent deterioration over prolonged cardiopulmonary bypass times, but diastolic dysfunction still occurs.     

A 1-Gb/s, 0.7-μm CMOS optical receiver with full rail-to-railoutput swing

This paper presents a 1-Gb/s optical receiver with full rail-to-rail output swing realized in a standard 0.7-μm CMOS technology. The receiver consists of a 1-kΩ transimpedance preamplifier followed by a postamplifier based on a biased inverter chain. The latter performs both a linear and a limiting amplification. The automatic biasing of the chain is provided through an offset tolerant replica circuit. The receiver requires no external components or biasing voltages. It is designed for a relatively large 0.8-pF input capacitance and is fed from a single 5-V power supply. These properties make the circuit suitable for a commercial environment. A sensitivity of 10 μA was measured at 1 Gb/s. The complete receiver, including all biasing and replicas, consumes approximately 100 mW from the 5-V supply. When powered from a 3.3-V supply, a maximal bit rate of 600 Mb/s is achieved, while the power consumption is reduced to approximately 26.5 mW     

Otoneurological manifestations in Chiari-I malformation

The type I Chiari malformation consists of a caudal displacement of the cerebellar tonsils through the foramen magnum into the cervical spinal canal. The most common presenting symptoms, such as pain, weakness and headache, are frequently preceded by otoneurological symptoms. Sensorineural hearing loss, vertigo, nystagmus, dysequilibrium, tinnitus and other cranial nerve involvement have been reported in Chiari-I malformation. A case report is presented and the clinical features of the disease are discussed with emphasis on the otoneurological aspects.     

丹麦城市集合住宅3例

BIG建筑师事务所是近年来崛起的丹麦年轻事务所之一,设计充满创意,常常令人耳目一新,上海世博会丹麦馆即出自其手笔。除了丹麦馆这样特殊的文化项目外,BIG事务所同样能将其独特的创意运用到要求较复杂的住宅项目中。虽然丹麦的居住习惯等现实条件与我国有异,但其设计中的巧思妙想,对我们亦可能有所启发。有鉴于此,特选刊其设计完成的3个居住项目(8住宅、vm住宅、山之宅),以飨读者。     

Employee substitutability as a tool to improve the robustness in personnel scheduling

OR Spectrum - Organisations usually construct personnel rosters under the assumption of a deterministic operating environment. In the short term, however, organisations operate in a stochastic...     

CMOS LED driver and PIN receiver for fiber optical communication at 150 mbit/sec

A test chip for an integrated full CMOS LED driver has been realized with a modulation current of 60 mA at a maximum bit rate of 155 Mb/s. A CMOS receiver is evaluated to amplify PIN diode photocurrents less than 10 µA at the same bit rate of 155 Mb/s. Both circuits are integrated on one chip. The circuit has been developed in a 0.8-µm digital CMOS process.