Amplitude death in a ring of nonidentical nonlinear oscillators with unidirectional coupling

We study the collective behaviors in a ring of coupled nonidentical nonlinear oscillators with unidirectional coupling, of which natural frequencies are distributed in a random way. We find the amplitude death phenomena in the case of unidirectional couplings and discuss the differences between the cases of bidirectional and unidirectional couplings. There are three main differences; there exists neither partial amplitude death nor local clustering behavior but oblique line structure which represents directional signal flow on the spatio-temporal patterns in the unidirectional coupling case. The unidirectional coupling has the advantage of easily obtaining global amplitude death in a ring of coupled oscillators with randomly distributed natural frequency. Finally, we explain the results using the eigenvalue analysis of Jacobian matrix at the origin and also discuss the transition of dynamical behavior coming from connection structure as coupling strength increases.Comment: 14 pages, 11 figure

Ultra-wideband CMOS signal generator using tunable linear superposition

Department of Electrical EngineeringWireless communication frequency bandwidth and center frequency are have been widening for high speed transmission of data. But the frequency bandwidth a transceiver can cover is severely limited. The circuit designed in the paper, called "signal generator", can offer a variety of wireless bandwidths. In this paper, a ultra wideband signal generator, based in 65nm CMOS technology, is designed after proposing and verifying two different types of signal generator design. The first version design of the signal generator is proposed, which is composed of a four-stage LC-ring voltagecontrolled oscillator (VCO) and a frequency synthesis circuit. A new concept of tunable linear superposition is proposed for wideband frequency synthesis and implemented to provide VCO core (1X)/ twofold (2X)/ quadruple (4X) programmable frequency multiplication function. In order to expand frequency coverage further, the LCring VCO adopted the tunable inductors which are composed of switchable bondwire pairs. A ultra-wideband operation from 4.3GHz to 27.4GHz was experimentally verified. The second version design of the signal generator using a reconfigurable phase selection process is proposed, which is proposed and consists of a multi-phase signal generation and a programmable frequency multiplication. This chip is proposed for wideband frequency synthesis and implemented to provide VCO core (1X)/ twofold (2X)/ quadruple (4X) and octuplet (8X) programmable frequency multiplication function. An LC-ring oscillator and a selective rectifying combiner are reconstructed adaptively for various frequency synthesis modes, minimizing their power consumption. A fully-integrated prototype verified to have very wide frequency characteristic from 6.3GHz to 59.4GHz.ope

Genome-wide functional analysis using the barcode sequence alignment and statistical analysis (Barcas) tool

Pipelines of pooled library screen analysis. Table S1. Public library sets of shRNA, sgRNA and deletion mutant strains. Figure S2. A list of wrong barcodes from 1,230 shRNAs of TRC library. Table S2. Sequences of 25 barcodes with abnormally increased mapping counts by imperfect matching. Table S3. A list of the used options for each tool. Table S4. Comparison of mapping results and speed by three tools. (PDF 7691 kb

Experimental Study on Coordinated Heading Control of Four Vessels Moored Side by Side

A floating type liquefied natural gas (LNG) bunkering terminal has been under development in Korea since 2014; the terminal is designed to receive LNG from an LNG carrier (LNGC) and transfer it to two other LNG bunkering shuttles (LNGBS) simultaneously. The operational feasibility of the LNG loading and unloading processes has been confirmed. When four vessels are moored side by side with mooring ropes and fenders, their positions must be maintained within the designed allowable criteria. In addition, the floating bunkering terminal (FLBT) has its own mooring system, an internal turret with catenary mooring lines and stern tunnel thrusters to maintain its own position and control the vessel heading. In this study, we investigated the operational feasibility of the FLBT during the LNG loading and unloading operations with four vessel mooring configurations and heading controls. A series of model tests was done in the ocean engineering basin of the Korea Research Institute of Ships and Ocean engineering. The motion responses of the four vessels were determined using an optical measurement system, and the tensile loads on ship-to-ship mooring ropes and the compressive loads on ship-to-ship fenders were measured using one-axis load cells. A white noise test was done and the results were compared with the numerical results for the purpose of validation. Then, four combined environmental conditions were presented both without heading control and with several heading control cases. Finally, we determined the available safe bunkering heading ranges taking into account the tensile loads on the mooring ropes

Isolated Shoulder Weakness due to a Small Cortical Infarction

Small cortical infarctions can produce isolated motor paresis in the upper extremities. Several cases of isolated hand or finger paresis have been reported, but isolated shoulder weakness is extremely rare. We report here a patient who developed isolated shoulder weakness due to a small cortical infarction in the medial precentral gyrus