37 research outputs found
Restructuring TCAD System: Teaching Traditional TCAD New Tricks
Traditional TCAD simulation has succeeded in predicting and optimizing the
device performance; however, it still faces a massive challenge - a high
computational cost. There have been many attempts to replace TCAD with deep
learning, but it has not yet been completely replaced. This paper presents a
novel algorithm restructuring the traditional TCAD system. The proposed
algorithm predicts three-dimensional (3-D) TCAD simulation in real-time while
capturing a variance, enables deep learning and TCAD to complement each other,
and fully resolves convergence errors.Comment: In Proceedings of 2021 IEEE International Electron Devices Meeting
(IEDM
Statement on chronotherapy for the treatment of hypertension: consensus document from the Korean society of hypertension
Nocturnal blood pressure (BP) has been shown to have a significant predictive value for cardiovascular disease. In some cases, it has a superior predictive value for future cardiovascular outcomes than daytime BP. As efficacy of BP medications wanes during nighttime and early morning, control of nocturnal hypertension and morning hypertension can be difficult. As such, chronotherapy, the dosing of BP medication in the evening, has been an ongoing topic of interest in the field of hypertension. Some studies have shown that chronotherapy is effective in reducing nocturnal BP, improving non dipping and rising patterns to dipping patterns, and improving cardiovascular prognosis. However, criticism and concerns have been raised regarding the design of these studies, such as the Hygia study, and the implausible clinical benefits in cardiovascular outcomes considering the degree of BP lowering from bedtime dosing. Studies have shown that there is no consistent evidence to suggest that routine administration of antihypertensive medications at bedtime can improve nocturnal BP and early morning BP control. However, in some cases of uncontrolled nocturnal hypertension and morning hypertension, such as in those with diabetes mellitus, chronic kidney disease, and obstructive sleep apnea, bedtime dosing has shown efficacy in reducing evening and early morning BP. The recently published the Treatment in Morning versus Evening (TIME) study failed to demonstrate benefit of bedtime dosing in reducing cardiovascular outcomes in patients with hypertension. With issues of the Hygia study and negative results from the TIME study, it is unclear at this time whether routine bedtime dosing is beneficial for reducing cardiovascular outcomes
Cache-assisted Mobile Edge Computing over Space-Air-Ground Integrated Networks for Extended Reality Applications
Extended reality-enabled Internet of Things (XRI) provides the new user
experience and the sense of immersion by adding virtual elements to the real
world through Internet of Things (IoT) devices and emerging 6G technologies.
However, the computational-intensive XRI tasks are challenging for the
energy-constrained small-size XRI devices to cope with, and moreover certain
data requires centralized computing that needs to be shared among users. To
this end, we propose a cache-assisted space-air-ground integrated network
mobile edge computing (SAGIN-MEC) system for XRI applications, consisting of
two types of edge servers mounted on an unmanned aerial vehicle (UAV) and low
Earth orbit (LEO) equipped with cache and the multiple ground XRI devices. For
system efficiency, the four different offloading procedures of the XRI data are
considered according to the type of information, i.e., shared data and private
data, as well as the offloading decision and the caching status. Specifically,
the private data can be offloaded to either UAV or LEO, while the offloading
decision of the shared data to the LEO can be determined by the caching status.
With the aim of maximizing the energy efficiency of the overall system, we
jointly optimize UAV trajectory, resource allocation and offloading decisions
under latency constraints and UAV's operational limitations by using the
alternating optimization (AO)-based method along with Dinkelbach algorithm and
successive convex optimization (SCA). Via numerical results, the proposed
algorithm is verified to have the superior performance compared to conventional
partial optimizations or without cache
Diagnosis of Eosinophilic Otitis Media Using Blood Eosinophil Levels
Eosinophilic otitis media (EOM) is a rare middle ear disease with unfavorable outcomes. Under the current diagnostic criteria of EOM, it is challenging to suspect EOM before tympanostomy. Therefore, this study attempted to use blood eosinophil levels for the differential diagnosis of EOM from other conditions. Three disease groups with features of recurrent otorrhea were categorized, which included the following: EOM (n = 9), granulomatosis with polyangiitis (GPA, n = 12), and primary ciliary dyskinesia (PCD, n = 6). Clinical and radiological characteristics were analyzed in the three groups. Patients who underwent ventilation tube insertion due to serous otitis media were enrolled as the control group (n = 225) to evaluate the diagnostic validity of blood eosinophilia. The EOM group showed a significantly higher blood eosinophil concentration (p p < 0.001) compared to the GPA and PCD groups. The estimated sensitivity and specificity for diagnosing EOM from OME patients who underwent ventilation tube insertion were 100% and 95.6%, respectively. In addition, EOM tended to have protympanic space soft tissue density and a relatively clear retrotympanic space in temporal bone computerized tomography. Blood eosinophil evaluation is a significant clinical indicator of EOM. Furthermore, the assessment of exclusive protympanic soft tissue density can provide an additional diagnostic clue
Investigation of the Probe-Factor Deconvolution Methods for Dynamic ESD Fields Measurements
Accurate measurements of electromagnetic fields are essential to analyze the radiated noise due to unwanted electrostatic discharge (ESD) events at electronic devices. Usually, to know the radiated noise by ESD events, the voltages induced at field probes are measured, and the fields are obtained from the voltage by de-convolving the probe factor. In this paper, the two probe-factor deconvolution methods are investigated and compared in the measurements of the fields induced by system-level ESD events
Development of clinical application program for radiotherapy induced cancer risk calculation using Monte Carlo engine in volumetric-modulated arc therapy
Abstract Background The purpose of this study is to develop a clinical application program that automatically calculates the effect for secondary cancer risk (SCR) of individual patient. The program was designed based on accurate dose calculations using patient computed tomography (CT) data and Monte Carlo engine. Automated patient-specific evaluation program was configured to calculate SCR. Methods The application program is designed to re-calculate the beam sequence of treatment plan using the Monte Carlo engine and patient CT data, so it is possible to accurately calculate and evaluate scatter and leakage radiation, difficult to calculate in TPS. The Monte Carlo dose calculation system was performed through stoichiometric calibration using patient CT data. The automatic SCR evaluation program in application program created with a MATLAB was set to analyze the results to calculate SCR. The SCR for organ of patient was calculated based on Biological Effects of Ionizing Radiation (BEIR) VII models. The program is designed to sequentially calculate organ equivalent dose (OED), excess absolute risk (EAR), excess relative risk (ERR), and the lifetime attributable risk (LAR) in consideration of 3D dose distribution analysis. In order to confirm the usefulness of the developed clinical application program, the result values from clinical application program were compared with the manual calculation method used in the previous study. Results The OED values calculated in program were calculated to be at most approximately 13.3% higher than results in TPS. The SCR result calculated by the developed clinical application program showed a maximum difference of 1.24% compared to the result of the conventional manual calculation method. And it was confirmed that EAR, ERR and LAR values can be easily calculated by changing the biological parameters. Conclusions We have developed a patient-specific SCR evaluation program that can be used conveniently in the clinic. The program consists of a Monte Carlo dose calculation system for accurate calculation of scatter and leakage radiation and a patient-specific automatic SCR evaluation program using 3D dose distribution. The clinical application program that improved the disadvantages of the existing process can be used as an index for evaluating a patient treatment plan
Measurement and Analysis of Statistical IC Operation Errors in a Memory Module Due to System-Level ESD Noise
Voltage noise and operation errors in an integrated circuit (IC) due to electrostatic discharge (ESD) events were measured, validated, and analyzed in this paper. A simplified structure of a laptop personal computer and an IC with a D-type flip-flop were designed and manufactured for the experimental tests. Every signal input to the IC was simultaneously measured during the ESD tests, and validated with the simulated results using a full-wave solver and a simple circuit model. Next, SPICE simulations were conducted using the measured voltages with ESD tests. The output waveforms and the statistical occurrence ratios of the operation failures found from the SPICE simulations were compared with measured values. Furthermore, the effects of decoupling capacitors on the IC operation failures due to ESD were investigated