University of California, Santa Barbara

About: University of California, Santa Barbara is a education organization based out in Santa Barbara, California, United States. It is known for research contribution in the topics: Population & Galaxy. The organization has 30281 authors who have published 80852 publications receiving 4626827 citations. The organization is also known as: UC Santa Barbara & UCSB.

Technology Adaptation: The Case of a Computer-Supported Inter-Organizational Virtual Team

Abstract: The adaptation process for new technology is not yet well understood. This study analyzes how an inter-organizational virtual team, tasked with creating a highly innovative product over a 10 month period, adapted the use of a collaborative technology and successfully achieved its challenging objectives. The study of such a virtual team is especially useful for extending our understanding of the adaptation process as virtual teams have more malleable structures than typical organizational units and controlled group experiments. Data were obtained from observations of weekly virtual meetings, electronic log files, interviews, and weekly questionnaires administered to team members. We found that the team initially experienced significant misalignments among the pre-existing organizational environment, group, and technology structures. To resolve these misalignments, the team modified the organizational environment and group structures, leaving the technology structure intact. However, as the team proceeded, a series of events unfolded that caused the team to re-evaluate and further modify its structures. This final set of modifications involved reverting back to the pre-existing organizational environment, while new technology and group structures emerged as different from both the pre-existing and the initial ones. A new model of the adaptation process - one that integrates these findings and those of several previous models - is proposed.

Linear systems theory

Abstract: Joao P Hespanha February 4, 2015 Comments and information about typos are very welcome Please contact the author at hespanha@eceucsbedu Errata 1) In page 7, the MATLAB R © command should read sys_ss=ss(A,B,C,D, ’InputName’, {’input1’, ’input2’,}, ’OutputName’,{’output1’,’output2’,}, ’StateName’, {’state1’, ’state2’,}); 2) In page 15 in Figure 23, the angle θ2 is incorrectly drawn, it should be drawn as follows:

Floquet Time Crystals.

Abstract: Time-translation symmetry can be spontaneously broken in driven quantum systems opening the door to time crystals, according to new theoretical predictions.

Enterprise Social Media: Definition, History, and Prospects for the Study of Social Technologies in Organizations

Abstract: Social media are increasingly implemented in work organizations as tools for communication among employees. As these technologies begin to proliferate across the enterprise, it is important that we develop an understanding of how they enable and constrain the communicative activities through which work is accomplished because it is these very dynamics that constitute and perpetuate organizations. We begin by offering a definition of enterprise social media and providing a rough historical account of the various avenues through which these technologies have entered and continue to enter the workplace. We also review areas of research covered by papers in this special issue and papers on enterprise social media published elsewhere to take stock of the current state of out knowledge and to propose directions for future research.

A subthermionic tunnel field-effect transistor with an atomically thin channel.

Abstract: A new type of device, the band-to-band tunnel transistor, which has atomically thin molybdenum disulfide as the active channel, operates in a fundamentally different way from a conventional silicon (MOSFET) transistor; it has turn-on characteristics and low-power operation that are better than those of state-of-the-art MOSFETs or any tunnelling transistor reported so far. Traditional transistor technology is fast approaching its fundamental limits, and two-dimensional semiconducting materials such as molybdenum disulfide (MoS2) are seen as possible replacements for silicon in a next generation of high-density, lower-power chip electronics. A particularly promising prospect is their potential in band-to-band tunnel transistors, which operate in a fundamentally different way from conventional silicon (MOSFET) transistors. So far, few such devices with overall characteristics better than silicon transistors have been demonstrated. Now Kaustav Banerjee et al. have built a tunnel transistor by making a vertical structure with atomically thin MoS2 as the active channel and germanium as the source electrode. It has turn-on characteristics and low-power operation that are better than those of existing silicon transistors, and the results will be of interest in a range of electronic applications including low-power integrated circuits, as well as ultra-sensitive bio sensors or gas sensors. The fast growth of information technology has been sustained by continuous scaling down of the silicon-based metal–oxide field-effect transistor. However, such technology faces two major challenges to further scaling. First, the device electrostatics (the ability of the transistor’s gate electrode to control its channel potential) are degraded when the channel length is decreased, using conventional bulk materials such as silicon as the channel. Recently, two-dimensional semiconducting materials1,2,3,4,5,6,7 have emerged as promising candidates to replace silicon, as they can maintain excellent device electrostatics even at much reduced channel lengths. The second, more severe, challenge is that the supply voltage can no longer be scaled down by the same factor as the transistor dimensions because of the fundamental thermionic limitation of the steepness of turn-on characteristics, or subthreshold swing8,9. To enable scaling to continue without a power penalty, a different transistor mechanism is required to obtain subthermionic subthreshold swing, such as band-to-band tunnelling10,11,12,13,14,15,16. Here we demonstrate band-to-band tunnel field-effect transistors (tunnel-FETs), based on a two-dimensional semiconductor, that exhibit steep turn-on; subthreshold swing is a minimum of 3.9 millivolts per decade and an average of 31.1 millivolts per decade for four decades of drain current at room temperature. By using highly doped germanium as the source and atomically thin molybdenum disulfide as the channel, a vertical heterostructure is built with excellent electrostatics, a strain-free heterointerface, a low tunnelling barrier, and a large tunnelling area. Our atomically thin and layered semiconducting-channel tunnel-FET (ATLAS-TFET) is the only planar architecture tunnel-FET to achieve subthermionic subthreshold swing over four decades of drain current, as recommended in ref. 17, and is also the only tunnel-FET (in any architecture) to achieve this at a low power-supply voltage of 0.1 volts. Our device is at present the thinnest-channel subthermionic transistor, and has the potential to open up new avenues for ultra-dense and low-power integrated circuits, as well as for ultra-sensitive biosensors and gas sensors18,19,20,21.