Jong-Ho Park

A high-performance CMOS image sensor (CIS) with 13-b column-parallel single-ended cyclic ADCs is presented. The simplified single-ended circuits for the cyclic ADC are squeezed into a 5.6-mum-pitch single-side column. The proposed internal reference generation and return-to-zero digital signal feedback techniques enhance the ADC to have low read noise, a high resolution of 13 b, and a resulting dynamic range of 71 dB. An ultralow vertical fixed pattern noise of 0.1 e <sub xmlns:mml="http://www.w

In RFID systems, tag collision resolution is significantly important for fast tag identification. In this letter, we propose an accurate and robust tag estimation method and an effective tag anti-collision protocol. Performance analysis and simulation results show that the proposed estimation and anti-collision algorithm consumes 10-15% less time slots than the binary tree protocol and dynamic framed slotted ALOHA (DFSA). The proposed algorithm has also tolerance to the inaccuracy of tag estimat

As one of the most attractive large-capacity energy storage systems, vanadium redox flow batteries have many advantages such as a rapid response, long service life, environment-friendliness, and non-flammability. However, the high cost of the vanadium electrolyte has hindered the broad market penetration. The price of the vanadium electrolyte can be significantly reduced if a cost-competitive technology for producing the electrolyte from recycled V2O5 may be used. Accordingly, the effects of the

Capacity decay in vanadium redox flow batteries during charge-discharge cycling has become an important issue because it lowers the practical energy density of the battery. The battery capacity tends to drop rapidly within the first tens of cycles and then drops more gradually over subsequent cycles during long-term operation. This paper analyzes and discusses the reasons for this early capacity decay. The imbalanced crossover rate of vanadium species was found to remain high until the total dif

An enhanced search algorithm of a landing site on unknown terrain using stereo vision information for a quadrotor unmanned aerial vehicle is developed. For the development, a quadrotor dynamic model, including nonlinear actuator dynamics, is constructed and guidance and control system is designed based on feedback linearization and linear quadratic tracker. Stereo vision sensor is used to acquire depth map information of the terrain and flatness information of the topography is obtained by extra

In far field RFID systems, tag collision resolution is significantly important for fast tag identification. In this paper, we propose an accurate tag estimation method and an effective tag anti-collision protocol. Performance evaluation that the proposed estimation and anti-collision algorithm consumes 10-15% less time slots than the binary tree protocol and DFSA. The proposed algorithm has the tolerance to inaccuracy of tag estimation.

The use of precast concrete modular construction in the replacement and rebuilding of old structures has recently increased. However, the joints between modules in this type of construction exhibit special behavior that should be considered when analyzing the behavior of modular members. Both stability and serviceability should be studied; however, existing research has only addressed the former. Research regarding serviceability, involving deflection and crack development and propagation, is la

Achieving a deep molecular response (DMR) to tyrosine kinase inhibitor (TKI) therapy for chronic myeloid leukemia (CML) remains challenging and at present, there is no biomarker to predict DMR in this setting. Herein, we report that an HMGCLL1 genetic variant located in 6p12.1 can be used as a predictive genetic biomarker for intrinsic sensitivity to imatinib (IM) therapy. We measured DMR rate according to HMGCLL1 variant in a discovery set of CML patients (n = 201) and successfully replicated i

In this paper, collision avoidance of a quadrotor unmanned aerial vehicle using stereo vision sensor is proposed. Quadrotor dynamic modeling is performed, and under-actuated problem of the quadrotor is dealt by introducing virtual inputs. Waypoint guidance and controller are designed using feedback linearization and linear quadratic tracker. Stereo vision is used to acquire depth map, and an obstacle is detected by the computed depth map. Then, collision cone approach is adopted to perform colli

The performance requirements of next-generation CMOS image sensors (CIS) have been increasing in terms of frame rate, read noise, dynamic range, as well as pixel resolution. In order to satisfy strict specifications, a column-parallel ADC is a key element in a state-of-the-art CIS. However, this architecture leads to side-effects such as vertical fixed pattern noise (VFPN) and read noise. In order to reduce these non-idealities, several techniques can be applied such as digital CDS using a singl

This paper gives a unified convergence analysis of additive Schwarz methods for general convex optimization problems. Resembling the fact that additive Schwarz methods for linear problems are preconditioned Richardson methods, we prove that additive Schwarz methods for general convex optimization are in fact gradient methods. Then an abstract framework for convergence analysis of additive Schwarz methods is proposed. The proposed framework applied to linear elliptic problems agrees with the clas