Barriers of digital transformation: The case of small indigenous businesses in Indonesia during COVID-19

An indigenous craft, Batik permeates the lives of Indonesians and represents national pride. Often established as a female-headed family enterprise, small Batik businesses in Indonesia’s Madura region are handed down from one generation to another and operate on a traditional brick-and-mortar retail channel, relying heavily on tourism to attract customers. COVID-19 lockdown has crippled that trading chain. E-commerce trading through digital platforms, such as e-marketplaces and social media, seems to be the only viable solution. A study of 12 small Batik businesses in Madura prior to, and after, the COVID-19 lockdown suggests significant barriers exist to digitally transform these businesses. Besides the usual environment, and socio-economic barriers to digital innovation such as illiteracy and lack of digital skills, reliance on younger family members and community support, indigeneity aspects such as ecological condition, socio-culture value and local wisdom, have been found to deter the transformation. We discuss the implications of these findings and suggest avenues for further exploration

Anti-phase locking in a two-dimensional Josephson junction array

We consider theoretically phase locking in a simple two-dimensional Josephson junction array consisting of two loops coupled via a joint line transverse to the bias current. Ring inductances are supposed to be small, and special emphasis is taken on the influence of external flux. Is is shown, that in the stable oscillation regime both cells oscillate with a phase shift equal to $\pi$ (i.e. anti-phase). This result may explain the low radiation output obtained so far in two-dimensional Josephson junction arrays experimentally.Comment: 11 pages, REVTeX, 1 Postscript figure, Subm. to Appl. Phys. Let

Diagnosing Cysts With Correlation Coefficient Images From 2‐Dimensional Freehand Elastography

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/135592/1/jum20072691201.pd

Theory of phase-locking in generalized hybrid Josephson junction arrays

A recently proposed scheme for the analytical treatment of the dynamics of two-dimensional hybrid Josephson junction arrays is extended to a class of generalized hybrid arrays with ''horizontal'' shunts involving a capacitive as well as an inductive component. This class of arrays is of special interest, because the internal cell coupling has been shown numerically to favor in-phase synchronization for certain parameter values. As a result, we derive limits on the circuit design parameters for realizing this state. In addition, we obtain formulas for the flux-dependent frequency including flux-induced switching processes between the in-phase and anti-phase oscillation regime. The treatment covers unloaded arrays as well as arrays shunted via an external load.Comment: 24 pages, REVTeX, 5 Postscript figures, Subm. to Phys. Rev.

27. New echocardiogram index alternatives to MAPSE and TAPSE z-scores in children

BackgroundMitral annular plane systolic excursion (MAPSE), and tricuspid annular plane systolic excursion (TAPSE) are relatively load independent longitudinal left ventricle (LV) and right ventricle (RV) measurement in both adults and children. Normal paediatric values of MAPSE and TAPSE unlike adults are based on inconvenient z-scores. We hypothesize novel indexes of (LSI) LV longitudinal systolic index and (RSI) RV longitudinal systolic index are BSA, age, gender independent and nullifies the need for MAPSE and TAPSE z-scores.MethodsNormal echocardiograms were retrospectively reviewed from 2009 to 2011. Ejection fraction, LV dimensions, MAPSE, and TAPSE were determined. LSI and RSI were calculated using MAPSE and TAPSE divided by LV length. Echocardiogram indices were correlated. Regression analysis was done for BSA, age, and gender.ResultsTwo hundred and one patients had normal ejection fractions (67.3;±5.1%). Mean MAPSE 10.4;±3.3mm, z-score −0.07;±1.2, and LSI 0.20;±0.03; Mean TAPSE 17.4;±5.4mm, z-score 0.74;±1.7, and RSI 0.34;±0.06. LSI and MAPSE z-scores correlated, r=0.73, p<0.001. Age, gender, and BSA did not correlate with LSI. RSI and TAPSE z-scores correlated with r=0.76, p<0.001. Age influences RSI, R2=0.58, p value <0.001, BSA and gender does not. RSI, with age stratification, is significantly decreased less than 2months.ConclusionLSI obviates need for-MAPSE z scores. RSI offers an additional non TAPSE z-score method to evaluate RV function, but does not nullify age effect. RSI, especially in the first two months is decreased

Automated Ultrasound Scanning on a Dual‐Modality Breast Imaging System

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/135219/1/jum2007265645.pd

Resonant-Cavity-Induced Phase Locking and Voltage Steps in a Josephson Array

We describe a simple dynamical model for an underdamped Josephson junction array coupled to a resonant cavity. From numerical solutions of the model in one dimension, we find that (i) current-voltage characteristics of the array have self-induced resonant steps (SIRS), (ii) at fixed disorder and coupling strength, the array locks into a coherent, periodic state above a critical number of active Josephson junctions, and (iii) when $N_a$ active junctions are synchronized on an SIRS, the energy emitted into the resonant cavity is quadratic with $N_a$. All three features are in agreement with a recent experiment [Barbara {\it et al}, Phys. Rev. Lett. {\bf 82}, 1963 (1999)]}.Comment: 4 pages, 3 eps figures included. Submitted to PRB Rapid Com

THEORY OF PHASE-LOCKING IN SMALL JOSEPHSON JUNCTION CELLS

Within the RSJ model, we performed a theoretical analysis of phase-locking in elementary strongly coupled Josephson junction cells. For this purpose, we developed a systematic method allowing the investigation of phase-locking in cells with small but non-vanishing loop inductance.The voltages across the junctions are found to be locked with very small phase difference for almost all values of external flux. However, the general behavior of phase-locking is found to be just contrary to that according to weak coupling. In case of strong coupling there is nearly no influence of external magnetic flux on the phases, but the locking-frequency becomes flux-dependent. The influence of parameter splitting is considered as well as the effect of small capacitive shunting of the junctions. Strongly coupled cells show synchronization even for large parameter splitting. Finally, a study of the behavior under external microwave radiation shows that the frequency locking-range becomes strongly flux-dependent, whereas the locking frequency itself turns out to be flux-independent.Comment: 26 pages, REVTEX, 9 PS figures appended in uuencoded form at the end, submitted to Phys. Rev. B

Full capacitance-matrix effects in driven Josephson-junction arrays

We study the dynamic response to external currents of periodic arrays of Josephson junctions, in a resistively capacitively shunted junction (RCSJ) model, including full capacitance-matrix effects}. We define and study three different models of the capacitance matrix $C_{\vec{r},\vec{r}'}$: Model A includes only mutual capacitances; Model B includes mutual and self capacitances, leading to exponential screening of the electrostatic fields; Model C includes a dense matrix $C_{\vec{r},\vec{r}'}$ that is constructed approximately from superposition of an exact analytic solution for the capacitance between two disks of finite radius and thickness. In the latter case the electrostatic fields decay algebraically. For comparison, we have also evaluated the full capacitance matrix using the MIT fastcap algorithm, good for small lattices, as well as a corresponding continuum effective-medium analytic evaluation of a finite voltage disk inside a zero-potential plane. In all cases the effective $C_{\vec{r},\vec{r}'}$ decays algebraically with distance, with different powers. We have then calculated current voltage characteristics for DC+AC currents for all models. We find that there are novel giant capacitive fractional steps in the I-V's for Models B and C, strongly dependent on the amount of screening involved. We find that these fractional steps are quantized in units inversely proportional to the lattice sizes and depend on the properties of $C_{\vec{r},\vec{r}'}$. We also show that the capacitive steps are not related to vortex oscillations but to localized screened phase-locking of a few rows in the lattice. The possible experimental relevance of these results is also discussed.Comment: 12 pages 18 Postscript figures, REVTEX style. Paper to appear in July 1, Vol. 58, Phys. Rev. B 1998 All PS figures include

Superconducting states and depinning transitions of Josephson ladders

We present analytical and numerical studies of pinned superconducting states of open-ended Josephson ladder arrays, neglecting inductances but taking edge effects into account. Treating the edge effects perturbatively, we find analytical approximations for three of these superconducting states -- the no-vortex, fully-frustrated and single-vortex states -- as functions of the dc bias current $I$ and the frustration $f$. Bifurcation theory is used to derive formulas for the depinning currents and critical frustrations at which the superconducting states disappear or lose dynamical stability as $I$ and $f$ are varied. These results are combined to yield a zero-temperature stability diagram of the system with respect to $I$ and $f$. To highlight the effects of the edges, we compare this dynamical stability diagram to the thermodynamic phase diagram for the infinite system where edges have been neglected. We briefly indicate how to extend our methods to include self-inductances.Comment: RevTeX, 22 pages, 17 figures included; Errata added, 1 page, 1 corrected figur