김병조 교수

In the IEEE Wireless Access in Vehicular Environment (WAVE), the periodic broadcast of the basic safety message (BSM) enables proximity awareness in the vehicle-to-vehicle (V2V) context. To maximize the level of awareness and consequently the driving safety, the BSM transmission at the highest allowed rate is desired in principle. A caveat, however, is controlling the BSM traffic within the given channel capacity because otherwise it can actually lower the delivery probability due to message col

The use of implantable medical devices (IMDs) are on the rise. Heart pacemakers, brain neurostimulators, cochlear implants, gastric stimulators, cardiac defibrillators, foot drop implants, and insulin pumps have been widely used, and more are on the horizon. Wireless communication capability for these devices is considered essential for these devices, for convenient monitoring and configuration [1]. But there also has been privacy and even safety concerns on the use of wireless medium due to the

Hydrogen plasma treatment (HPT) is commonly employed to enhance the interface quality of high-k metal-oxide gate stacks in semiconductor, but the plasma process is highly sensitive to variations in process parameters. The modulation of processing conditions to meet the increasing demand for atomic-precision in device feature is severely challenging without a proper understanding of the plasma-facing surface. This study aimed to provide atomistic insights on HPT to improve the quality of high-k m

Abstract With the advent of complex and sophisticated architectures in semiconductor device manufacturing, atomic-resolution accuracy and precision are commonly required for industrial plasma processing. This demands a comprehensive understanding of the plasma–material interactions—particularly for forming fine high-aspect ratio (HAR) feature patterns with sufficiently high yield in wafer-level processes. In particular, because the shape distortion in HAR pattern etching is attributed to the dev

Recently, eMMC is widely being used in mobile devices because of its characteristics such as low cost, small size, and low power consumption. In this paper, we analyze features of eMMC based on commands such as Trim, Discard, and Background to investigate how do commands affect the random write performance and lifetime of the NAND flash memory. Also, we propose a method that uses the Background command to improve the random write performance of eMMC. Our experimental results clearly show that ou

In this paper, we propose an energy-efficient transmission scheme for wireless powered communication networks with harvest-then-transmit protocol. Specifically, considering fairness among users, we present time resource allocation scheme to maximize the individual energy efficiency(EE) of each user, defined as a ratio of the user throughput to its harvested energy,based on the max-min criterion. EE optimization problem is highly non-convex and difficult to directly tackle. To solve this difficul

A multiscale modeling approach is proposed to account for the interfacial load transfer characteristics of epoxy nanocomposites. The localized stress evolutions in nanocomposites are examined with molecular dynamics (MD) simulations: the particle phase stress and the regional stress evolution in matrix medium. Plus, detailed atomic motions in the matrix phase are thoroughly studied with respect to the crosslink conversion. The distinct structural features in a highly crosslinked system induce a

This paper proposes QoS-constrained energy-efficiency (EE) maximization scheme in a multi-antenna wireless powered network. Specifically, considering full CSI at the users, we optimize energy transmit covariance at the power transmitter, the power allocation at the users and the time allocation for energy and information transfer. The EE optimization problem is first converted into its equivalent parameterized subtractive form and, then, the corresponding optimal solution is determined via the L

In this letter, we develop a novel scheme for joint channel estimation, training design, transmit (Tx) power allocation, and receive (Rx) power splitting in multiple-input multiple-output (MIMO) simultaneous wireless information and power transfer (SWIPT) systems, which maximizes the average signal-to-error-plus-noise ratio (SENR) with average harvested energy constraints at the receiver. To solve this challenging design problem, we first convert it into a more tractable form, which enables to d