The Dr. Chi capstone project team created the mobile application Dr. Chi. This application contains a program on the iOS platform and a sensor gadget which implements pulse reading as in Chinese medicine. Through measuring, storing and analyzing the heart pulse data, this application can give users instructive suggestions on stress management. We selected and optimized the sensor component for the sensor gadget by studying numbers of different kinds of sensors to improve the sensor precision.

关键词：智能手机；监测和诊断；应用程序；心脏脉冲；嵌入式传感器；脉冲；医疗器械

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We examine in detail the impact of passivating ligands (i.e., amines, phosphines, phosphine oxides and pyridines) on the electronic and optical spectra of Cd(sub 33)Se(sub 33) quantum dots (QDs) using density functional theory (DFT) and time-dependent DFT (TDDFT) quantum-chemical methodologies. Most ligand orbitals are found deep inside in the valence and conduction bands of the QD, with pyridine being an exception by introducing new states close to the conduction band edge. Importantly, all ligands contribute states which are highly delocalized over both the QD surface and ligands, forming hybridized orbitals rather than ligand-localized trap states. In contrast, the states close to the band gap are delocalized over the QD atoms only and define the lower energy absorption spectra. The random detachment of one of ligands from the QD surface results in the appearance of a highly localized unoccupied state inside the energy gap of the QD. Such changes in the electronic structure are correlated with the respective QD-ligand binding energy and steric ligand-ligand interactions. Polar solvent significantly reduces both effects leading to delocalization and stabilization of the surface states. Thus, trap and surface states are substantially eliminated by the solvent. Polar solvent also blue-shifts (e.g., 0.3-0.4 eV in acetonitrile) the calculated absorption spectra. This shift increases with an increase of the dielectric constant of the solvent. We also found that the approximate single-particle Kohn-Sham (KS) approach is adequate for calculating the absorption spectra of the ligated QDs. Besides a systematic blue-shift, the KS spectra are in very good agreement with their respective counterparts calculated with the more accurate TDDFT method.

关键词：电子信息；半导体；纳米晶体；电子性质

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Bulk magnetoresistance quantum oscillations are observed in high quality single crystal samples of BiTeI. This compound shows an extremely large internal spin-orbit coupling, associated with the polarity of the alternating Bi, Te, and I layers perpendicular to the c-axis. The corresponding areas of the inner and outer Fermi surfaces around the A-point show good agreement with theoretical calculations, demonstrating that the intrinsic bulk Rashba-type splitting is nearly 360 meV, comparable to the largest spin-orbit coupling generated in heterostructures and at surfaces.

关键词：电子信息；半导体；舒勃尼科夫—德哈斯振荡

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A combination of rising energy costs, a desire for national energy independence, and a growing awareness of the dangers of global climate change is pushing Americans to do what they can to save energy. Consumers now buy more fuel-efficient cars and appliances and are growing more aware of their use habits. While it is easy to see how much gas your car uses, beyond the labeling on major appliances at the point of sale, most consumers are unaware of how much electricity these devices actually use. In this Masters of Engineering Capstone Project we designed and implemented a wireless power monitor which sits on a conventional power outlet and is thin enough that an appliance plugs throughs. The power of the appliance being plugged through our device is monitored. The monitor is powered by either making direct contact with the prongs of the plug or by inductively harvesting through a contactless transformer. The latter case puts severe power restrictions on the mote which we overcame by using low-power hardware and OpenWSN, a network stack intended for low power, low data-rate applications such as ours.

关键词：能量收集；无线电力监控；无线网络；无线传感器网络基础平台

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This paper focuses on the design and implementation of one of the applications for HydraScope. The wall search application enables users to have a big picture of the search results and automatically open the links for users. A user study with ten participants reveals that the searching becomes more efficient by using HydraScope’s search application.

关键词：高分辨率的墙大小的显示屏；智能手机；微软体感控制器；触摸屏设备；远程控制；搜索服务器；应用程序

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We present the results of a two-year early career LDRD that focused on defect localization in deep green and deep ultraviolet (UV) light-emitting diodes (LEDs). We describe the laser-based techniques (TIVA/LIVA) used to localize the defects and interpre.

关键词：电子信息；半导体；LED；失效模式

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Electronics designed for use in NASA space missions are required to work efficiently and reliably under harsh environment conditions. These Include radiation, extreme temperatures, thermal cycling, to name a few. Preliminary data obtained on new Gallium Nitride and Silicon Carbide power devices under exposure to radiation followed by long term thermal cycling are presented. This work was done in collaboration with GSFC and JPL in support of the NASA Electronic Parts and Packaging (NEPP) Program.

关键词：电子信息；半导体；热循环；航天

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We have investigated for the first time the electrical properties of metal-semiconductor-metal (MSM) photodectors fabricated using black silicon- germanium on silicon substrate (Si1-xGex/Si) for I-V, optical response, external quantum efficiency (EQE), internal quantum efficiency (IQE), and responsivity and reflectivity. Silicon-germanium (Si1-xGex)/Si with variations of Ge were blackened by metal enhanced chemical etching (MECE) using nanometer- scale gold particles as catalyst and HF:H2O2:CH3COOH solution as etchant. The etched surface was black, textured, and showed strong suppression of reflectivity. These properties are consistent with Si1-xGex becoming highly micro-structured due to metal catalysis and wet etching. Using the blackened SiGe/Si, MSM photodiodes were fabricated and tested. The lowering of reflection using a U.S. Army Research Laboratory (ARL)-developed technique has helped the enhancement of absorption in Si1-xGex to provide increased optical response, which is an important milestone towards practical, extended wavelength (approximately 2 microns) electro-optical applications.

关键词：电子信息；半导体；光电探测器；锗硅

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We present the LU decomposition with panel rank revealing pivoting (LU PRRP), an LU factorization algorithm based on strong rank revealing QR panel factorization. Our extensive numerical experiments show that the new factorization scheme is as numerically stable as GEPP in practice, but it is more resistant to pathological cases and easily solves the Wilkinson matrix and the Foster matrix. The LU PRRP factorization does onlyO(n2b) additional floating point operations compared to GEPP.We also present CALU PRRP, a communication avoiding version of LU PRRP that minimizes communication. CALU PRRP is based on tournament pivoting, with the selection of the pivots at each step of the tournament being performed via strong rank revealing QR factorization.

关键词：LU分解；QR分解；数值实验；GEPP

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Performant execution of data-parallel jobs needs good executionplans. Certain properties of the code, the data, and the interaction between them are crucial to generate these plans. Yet, these propertiesare dicult to estimate due to the highly distributed nature of theseframeworks, the freedom that allows users to specify arbitrary code，as operations on the data, and since jobs in modern clusters haveevolved beyond single map and reduce phases to logical graphs ofoperations. Using xed apriori estimates of these properties to chooseexecution plans, as modern systems do, leads to poor performance inseveral instances. We present RoPE, a rst step towards re-optimizingdata-parallel jobs. RoPE collects certain code and data properties bypiggybacking on job execution. It adapts execution plans by feedingthese properties to a query optimizer. We show how this improves thefuture invocations of the same (and similar) jobs and characterize thescenarios of benet. Experiments on Bing's production clusters showup to 2 improvement across response time for production jobs at the75th percentile while using 1:5 fewer resources.

关键词：优化数据并行计算；查询优化器；高效执行

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