Connected vehicles are at risk of exposing their location history when using potentially untrusted location-based services (LBSs) in the driving process. We propose a method called mutually ...obfuscating paths (MOP) that enables vehicles to provide highly accurate realtime location updates to LBS while preventing the LBS from tracking vehicles. The instrument is to leverage connected vehicles' two network interfaces: in-car LTE Internet (for accessing LBS) and car-to-car Dedicated short-range communications (DSRC)-communication (for obfuscating their paths). The main idea of MOP is that vehicles, when appropriate, generate made-up but plausible location updates for each other, making their paths continuously branching off from the LBS' viewpoint. We evaluations show that MOP provides strong privacy protection even under continuous and highly accurate location updates.
Abstract
Colloidal Ag(In,Ga)S
2
nanocrystals (AIGS NCs) with the band gap tunability by their size and composition within visible range have garnered surging interest. High absorption cross-section ...and narrow emission linewidth of AIGS NCs make them ideally suited to address the challenges of Cd-free NCs in wide-ranging photonic applications. However, AIGS NCs have shown relatively underwhelming photoluminescence quantum yield (PL QY) to date, primarily because coherent heteroepitaxy has not been realized. Here, we report the heteroepitaxy for AIGS-AgGaS
2
(AIGS-AGS) core-shell NCs bearing near-unity PL QYs in almost full visible range (460 to 620 nm) and enhanced photochemical stability. Key to the successful growth of AIGS-AGS NCs is the use of the Ag-S-Ga(OA)
2
complex, which complements the reactivities among cations for both homogeneous AIGS cores in various compositions and uniform AGS shell growth. The heteroepitaxy between AIGS and AGS results in the Type I heterojunction that effectively confines charge carriers within the emissive core without optically active interfacial defects. AIGS-AGS NCs show higher extinction coefficient and narrower spectral linewidth compared to state-of-the-art heavy metal-free NCs, prompting their immediate use in practicable applications including displays and luminescent solar concentrators (LSCs).
The composite cathode of an all-solid-state battery composed of various solid-state components requires a dense microstructure and a highly percolated solid-state interface different from that of a ...conventional liquid-electrolyte-based Li-ion battery. Indeed, the preparation of such a system is particularly challenging. In this study, quantitative analyses of composite cathodes by three-dimensional reconstruction analysis were performed beyond the existing qualitative analysis, and their microstructures and reaction interfaces were successfully analyzed. Interestingly, various quantitative values of structure properties (such as the volume ratio, connectivity, tortuosity, and pore formation) associated with material optimization and process development were predicted, and they were found to result in limited electrochemical charge/discharge performances. We also verified that the effective two-phase boundaries were significantly suppressed to ∼23% of the total volume because of component dispersion and packing issues.
Full text
Available for:
IJS, KILJ, NUK, PNG, UL, UM
The structure and electrochemical properties of epitaxial thin film LiNi0.5Mn1.5O4 electrodes are investigated for lithium ion secondary batteries applications. The orientation and thickness of the ...LiNi0.5Mn1.5O4 films are controlled by changing the substrate orientation and the pulse laser deposition time, respectively. The lattice parameters of the films increase with film thickness and the manganese valence decreases without any change in the nickel valence. Regardless of their orientation, all the films exhibit reversible capacities of 80a130 mAh ga1. The dependence of the discharge capacity on film thickness indicates a nanosize effect. The electrochemical properties of the high voltage spinel system are significantly dependent on their electronic properties, lattice orientations, and film thicknesses of the electrodes.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
This article shows potential of using DSRC radios for vehicle tracking protection. We focus on traffic data collection as our target application where vehicles send their locations to a server while ...driving. Such vehicles are easily trackable-revealing location history-as the application often requires frequent and accurate location updates. This article presents PathCloak, a method that enables vehicles to report their locations while preventing the server from properly tracking the vehicles. PathCloak leverages vehicles' two network interfaces: in-car Internet (for accessing the server) and car-to-car DSRC (for creating path confusion). PathCloak-enabled vehicles exchange their kinematic information via DSRC radios, and use it to generate plausible path segments for each other, making their paths indistinguishable each other from the server's viewpoint. We demonstrate its feasibility via field experiments on real roads using our DSRC testbeds. Our evaluation shows that PathCloak offers strong privacy (tracking success ratio< 1%), while maintaining high utility for various traffic statistics.
In this paper, we first propose an efficient crosstalk-included eye-diagram estimation method for high-speed interposer channel on 2.5-D and three-dimensional (3-D) IC. The proposed method includes ...crosstalk effects from adjacent channels, which can considerably degrade the transmitted signal on a victim channel. This method enables to estimate worst and statistical eye-diagrams in a short time with high accuracy. While 3-D EM simulation has been widely used for accurate estimation of the channel performance, it requires substantial amount of computational time and resources. Therefore, in order to reduce the eye-diagram estimation time, the coupled microstrip channels are modeled using resistance, inductance, conductance, and capacitance components, whose values are derived from the physical dimensions. The equivalent circuit model can also enhance physical insight of the coupled channels. The proposed method is verified by time-domain simulations and measurements at data rates of up to 4 Gb/s. According to the estimated crosstalk-included eye-diagrams, the proposed method reduces simulation time over 99% and shows a high accuracy of approximately 93%. The proposed method is applied to the high-bandwidth memory channels on silicon, organic, and glass interposer.
Abstract Introduction This study evaluates the association between the Eastern Cooperative Oncology Group Performance Status (ECOG-PS) and hospital mortality in general critically ill patients. ...Materials and Methods This is a retrospective cohort study that analyzes prospective collected data from the Validation of Simplified acute physiology score 3 in Korean Intensive care unit study. The study population comprised patients who were consecutively admitted to participating intensive care units from July 1, 2010, to January 31, 2011. Univariate and multivariate logistic regression models were used to evaluate the effect of ECOG-PS on hospital mortality. Results A total of 3868 patients were included in the analysis. There was a significant trend for increasing hospital mortality as the ECOG-PS grade became higher ( P < .001). There was a trend of increasing adjusted odds ratio for hospital mortality, with grade 1 of PS 1.4 (95% confidence intervals CIs, 1.0-1.8), grade 2 of PS 2.0 (95% CIs, 1.5-2.7), grade 3 of PS 2.9 (95% CIs, 2.1-4.1), and grade 4 of PS 2.5 (95% CIs, 1.6-3.9). Also, there was a significant difference in all grades. Subgroup analysis showed a trend of increasing hospital mortality regardless of the presence of cancer. Conclusion Preadmission PS, assessed with ECOG-PS in critically ill patients, has prognostic value in general critically ill patients.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
A novel epitaxial thin-film electrode for lithium batteries, with a composition of Li sub(0.92)Co sub(0.65)Mn sub(1.35)O sub(4) and a cubic spinel structure, is fabricated on a SrTiO sub(3)(111) ...single-crystal substrate. Fabrication is carried out by layer-by-layer pulsed laser deposition of LiCoO sub(2) with a layered rock-salt structure and LiMn sub(2)O sub(4) with a spinel structure. The electrode is found to exhibit unique disordering of the lithium (8a) and transition-metal (16d) sites, leading to a higher rate capability and cycle retention ratio than those for a thin-film electrode with the same composition prepared by a conventional single-step deposition process. The proposed layer-by-layer deposition method allows an expanded range of compositional and structural variations for lithium battery electrode materials.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
As the data rate of Low Power Double Data Rate 4 (LPDDR4) memory now exceeds 3.2 Gb/s, it is becoming more difficult to meet the target specifications. While testing has become of utmost importance, ...it is not viable to have a direct access to the signal pins in a package on package configuration due to the densely located array of solder balls; instead, a test interposer with an excellent electrical performance needs to be adopted to provide test access. In this paper, we first propose a novel test interposer scheme for testing LPDDR4 memory packages. For accurate testing without significant influence on the intrinsic signal path, the proposed test interposer is designed considering a number of signal integrity issues such as intersymbol interference, jitter, impedance matching, and crosstalk. Furthermore, by adopting silicone rubber sheet in place of soldering, the proposed test interposer enhances reusability of the packages with a fast setup time. Moreover, a reconstruction method is proposed that can reconstruct the voltage at application processor using the waveform captured on the test interposer, instead of probing at the ball gray array directly. Through a series of simulations and measurements, we experimentally verified the proposed test interposer. The proposed test interposer scheme can be widely adopted for testing of high-performance packages with its high accuracy and practicality.
PDF
