2,047 research outputs found
Electron Delocalization in Gate-Tunable Gapless Silicene
The application of a perpendicular electric field can drive silicene into a
gapless state, characterized by two nearly fully spin-polarized Dirac cones
owing to both relatively large spin-orbital interactions and inversion symmetry
breaking. Here we argue that since inter-valley scattering from non-magnetic
impurities is highly suppressed by time reversal symmetry, the physics should
be effectively single-Dirac-cone like. Through numerical calculations, we
demonstrate that there is no significant backscattering from a single impurity
that is non-magnetic and unit-cell uniform, indicating a stable delocalized
state. This conjecture is then further confirmed from a scaling of conductance
for disordered systems using the same type of impurities.Comment: 6 pages, 3 figures, published versio
Nonsurjective zero product preservers between matrices over an arbitrary field
In this paper, we give concrete descriptions of additive or linear
disjointness preservers between matrix algebras over an arbitrary field
of different sizes. In particular, we show that a linear map
preserving zero products
carries the form for some invertible matrices in
, in and a zero product preserving
linear map with
range consisting of nilpotent matrices. Here, either or can be
vacuous. The structure of could be quite arbitrary. We classify
with some additional assumption. When has a zero nilpotent
part, especially when is diagonalizable, we have
for all in , and we give more
information about in this case. Similar results for double zero
product preservers and orthogonality preservers are obtained.Comment: 29 page
Design And Fabrication of Condenser Microphone Using Wafer Transfer And Micro-electroplating Technique
A novel fabrication process, which uses wafer transfer and
micro-electroplating technique, has been proposed and tested. In this paper,
the effects of the diaphragm thickness and stress, the air-gap thickness, and
the area ratio of acoustic holes to backplate on the sensitivity of the
condenser microphone have been demonstrated since the performance of the
microphone depends on these parameters. The microphone diaphragm has been
designed with a diameter and thickness of 1.9 mm and 0.6 m, respectively,
an air-gap thickness of 10 m, and a 24% area ratio of acoustic holes to
backplate. To obtain a lower initial stress, the material used for the
diaphragm is polyimide. The measured sensitivities of the microphone at the
bias voltages of 24 V and 12 V are -45.3 and -50.2 dB/Pa (at 1 kHz),
respectively. The fabricated microphone shows a flat frequency response
extending to 20 kHz.Comment: Submitted on behalf of EDA Publishing Association
(http://irevues.inist.fr/handle/2042/16838
Fever Screening at Airports and Imported Dengue
Airport fever screening in Taiwan, July 2003–June 2004, identified 40 confirmed dengue cases. Results obtained by capture immunoglobulin (Ig) M and IgG enzyme-linked immunoassay, real time 1-step polymerase chain reaction, and virus isolation showed that 33 (82.5%) of 40 patients were viremic. Airport fever screening can thus quickly identify imported dengue cases
Invited; CMOS inverters and circuits based on oxide thin-film transistors
Thin-film transistors (TFTs) based on oxide semiconductors have the advantage of promising carrier mobilities and good switching characteristics, and they can be fabricated by low-temperature and scalable processes. Complementary metal-oxide-semiconductor (CMOS) technology employing oxide TFTs shows great potential in enabling flexible electronics with versatile functionalities and low-static power consumptions. Here flexible CMOS inverters comprising p-type SnO TFTs and n-type ZnO or IGZO TFTs integrated in three different configurations were implemented and compared, as shown in Fig. 1. First, the planar inverter comprising bottom-gated SnO and ZnO TFTs with a geometric aspect ratio, (W/L)p / (W/L)n, of 5 had a static voltage gain of ~ 10 V/V at a supplied voltage (VDD) of 10 V [1]. However, the gain decreased as the inverter was subjected to a mechanical tensile strain, which may be ascribed to the degradation of TFT mobilities.
Please click Download on the upper right corner to see the full abstract
Intraclass reliability for assessing how well Taiwan constrained hospital-provided medical services using statistical process control chart techniques
BACKGROUND: Few studies discuss the indicators used to assess the effect on cost containment in healthcare across hospitals in a single-payer national healthcare system with constrained medical resources. We present the intraclass correlation coefficient (ICC) to assess how well Taiwan constrained hospital-provided medical services in such a system. METHODS: A custom Excel-VBA routine to record the distances of standard deviations (SDs) from the central line (the mean over the previous 12 months) of a control chart was used to construct and scale annual medical expenditures sequentially from 2000 to 2009 for 421 hospitals in Taiwan to generate the ICC. The ICC was then used to evaluate Taiwan’s year-based convergent power to remain unchanged in hospital-provided constrained medical services. A bubble chart of SDs for a specific month was generated to present the effects of using control charts in a national healthcare system. RESULTS: ICCs were generated for Taiwan’s year-based convergent power to constrain its medical services from 2000 to 2009. All hospital groups showed a gradually well-controlled supply of services that decreased from 0.772 to 0.415. The bubble chart identified outlier hospitals that required investigation of possible excessive reimbursements in a specific time period. CONCLUSION: We recommend using the ICC to annually assess a nation’s year-based convergent power to constrain medical services across hospitals. Using sequential control charts to regularly monitor hospital reimbursements is required to achieve financial control in a single-payer nationwide healthcare system
Antipsychotic Prescription Trends, Patterns and Associated Factors in Taiwanese Children and Adolescents
This study evaluated the prescription trends, patterns and associated factors of antipsychotic medication in children and adolescents. We conducted a retrospective study by using the database of outpatient health insurance files of a psychiatric center in Northern Taiwan from 2004 to 2013. A total of 173,209 outpatient health insurance files were included. The average age of the study patients was 11.3 (±3.9) years. Of all visits of the patients, 13.4% were prescribed antipsychotics. The prescription rate of all antipsychotic medication types in all the outpatients aged ≤18 years increased yearly by 0.6%. The prescription rate of first-generation antipsychotics decreased with an estimated average annual percent change of 5.6% (p < .001). By contrast, the prescription rate of second-generation antipsychotics increased with an estimated average annual percent change of 3.4% (p <.001). Multiple logistic regression analysis was performed to examine clinical factors (age, sex and diagnosis) associated with antipsychotic prescription. After adjusting for other variables, antipsychotic prescription was found to be increased by 1.31 times every year with age and by 1.06 times in the male patients. The patients with diagnoses other than schizophrenia appeared less likely to be prescribed antipsychotics. Antipsychotic medications are being increasingly prescribed to children and adolescents in recent years. T he efficacy and safety of antipsychotics in children and adolescents warrant clinical attention
- …