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We review the motivation, goals, and achievements of the Photonic Integrated Networked Energy efficient datacenter (PINE) project, which is part of the Advanced Research Projects Agency-Energy (ARPA-E) ENergy-efficient Light-wave Integrated Technology Enabling Networks that Enhance Dataprocessing (ENLITENED) program. The PINE program leverages the unique features of photonic technologies to enable alternative mega-datacenters and high-performance computing (HPC) system architectures that deliver more substantial energy efficiency improvements than can be achieved through link energy efficiency alone. In phase 1 of the program, the PINE system architecture demonstrated an average factor of 2.2 ×2.2× improvement in transactions/joule across a diverse set of HPC and datacenter applications. In phase 2, PINE will demonstrate an aggressive 1.0 pJ/bit total link budget with high-bandwidth-density dense wavelength-division multiplexing (DWDM) links to enable additional 2.5 ×2.5× or more efficiency gains through deep resource disaggregation.

Utilizing multistatic specular meteor radar (MSMR) observations, this study delves into global aspects of wind perturbations in the mesosphere and lower thermosphere (MLT) from the unprecedented 2022 eruption of the Hunga Tonga‐Hunga Ha'apai (HTHH) submarine volcano. The combination of MSMR observations from different viewing angles over South America and Europe, and the decomposition of the horizontal wind in components along and transversal to the HTHH eruption's epicenter direction allow an unambiguous detection and identification of MLT perturbations related to the eruption. The performance of this decomposition is evaluated using Whole Atmosphere Community Climate Model with thermosphere/ionosphere extension (WACCM‐X) simulations of the event. The approach shows that indeed the HTHH eruption signals are clearly identified, and other signals can be easily discarded. The winds in this decomposition display dominant Eastward soliton‐like perturbations observed as far as 25,000 km from HTHH, and propagating at 242 m/s. A weaker perturbation observed only over Europe propagates faster (but slower than 300 m/s) in the Westward direction. These results suggest that we might be observing the so‐called Pekeris mode, also consistent with the L1 pseudomode, reproduced by WACCM‐X simulations at MLT altitudes. They also rule out the previous hypothesis connecting the observations in South America to the Tsunami associated with the eruption because these perturbations are observed over Europe as well. Despite the progress, the L0 pseudomode in the MLT reproduced by WACCM‐X remains elusive to observations. Key Points: A decomposition of the horizontal wind in longitudinal and transverse components, allows clear identification of Hunga Tonga‐Hunga Ha'apai eruption signaturesEastward soliton‐like mesosphere and lower thermosphere horizontal wind perturbations are observed propagating at 242 m/s, up to at least 25,500 km from the epicenterWeaker westward propagating perturbations are observed at phase speeds in between the expected L0 and L1 speeds, but up to 17,000 km [ABSTRACT FROM AUTHOR]

We present the first reliability study of InAs/GaAs self-assembled quantum dot lasers epitaxially grown on Ge/Si substrates. Some devices maintain lasing oscillation after more than 2700 h of constant current stress at 30 °C, longer than any previous life tests of GaAs lasers epitaxially grown on silicon. No catastrophic failures were observed. The lasers were characterized to gain insight on the aging mechanism.

A narrow-band sodium lidar provides high temporal and vertical resolution observations of sodium density, atmospheric temperature, and wind that facilitate the investigation of atmospheric waves in the mesosphere and lower thermosphere (80–105 km). In order to retrieve full vector winds, such a lidar is usually configured in a multi-direction observing mode, with laser beams pointing to the zenith and several off-zenith directions. Gravity wave events were observed by such a lidar system from 06:30 to 11:00 UT on 14 January 2002 at Maui, Hawaii (20.7° N, 156.3° W). A novel method based on cross-spectrum was proposed to derive the horizontal wave information from the phase shifts among measurements in different directions. At least two wave packets were identified using this method: one with a period of ∼ 1.6 h, a horizontal wavelength of ∼ 438 km, and propagating toward the southwest; and the other one with a ∼ 3.2 h period, a ∼ 934 km horizontal wavelength, and propagating toward the northwest. The background atmosphere states were also fully measured and all intrinsic wave properties of the wave packets were derived. Dispersion and polarization relations were used to diagnose wave propagation and dissipation. It was revealed that both wave packets propagate through multiple thin evanescent layers and are possibly partially reflected but still get a good portion of energy to penetrate higher altitudes. A sensitivity study demonstrates the capability of this method in detecting medium-scale and medium-frequency gravity waves. With continuous and high-quality measurements from similar lidar systems worldwide, this method can be utilized to detect and study the characteristics of gravity waves of specific spatiotemporal scales. [ABSTRACT FROM AUTHOR]

This question of disciplinary meaning—which I ask from the viewpoint of the humanities generally—is larger than the question of disciplinary identity now preoccupying “DH” itself, as insiders call it. Having reached a critical mass of participants, publications, conferences, grant competitions, institutionalization (centers, programs, and advertised jobs), and general visibility, the field is vigorously forming an identity. Recent debates about whether the digital humanities are a “big tent” (Jockers and Worthey), “who's in and who's out?” (Ramsay), whether “you have to know how to code [or be a builder]” (Ramsay, “On Building”), the need for “more hack, less yack” (Cecire, “When Digital Humanities”; Koh), and “who you calling untheoretical?” (Bauer) witness a dialectics of inclusion and exclusion not unlike that of past emergent fields. An ethnographer of the field, indeed, might take a page from Claude Lévi-Strauss and chart the current digital humanities as something like a grid of affiliations and differences between neighboring tribes. Exaggerating the differences somewhat, as when a tribe boasts its uniqueness, we can thus say that the digital humanities—much of which affiliates with older humanities disciplines such as literature, history, classics, and the languages; with the remediation of older media such as books and libraries; and ultimately with the value of the old itself (history, archives, the curatorial mission)—are not the tribe of “new media studies,” under the sway of the design, visual, and media arts; Continental theory; cultural criticism; and the avant-garde new. Similarly, despite significant trends toward networked and multimodal work spanning social, visual, aural, and haptic media, much of the digital humanities focuses on documents and texts in a way that distinguishes the field's work from digital research in media studies, communication studies, information studies, and sociology. And the digital humanities are exploring new repertoires of interpretive or expressive “algorithmic criticism” (the “second wave” of the digital humanities proclaimed in “The Digital Humanities Manifesto 2.0” [3]) in a way that makes the field not even its earlier self, “humanities computing,” alleged to have had narrower technical and service-oriented aims. Recently, the digital humanities' limited engagement with identity and social-justice issues has also been seen to be a differentiating trait—for example, by the vibrant #transformDH collective, which worries that the digital humanities (unlike some areas of new media studies) are dominantly not concerned with race, gender, alternative sexualities, or disability.

The scholarly field of the digital humanities has recently expanded and integrated its fundamental concepts, historical coverage, relationship to social experience, scale of projects, and range of interpretive approaches. All this brings the overall field (including the related area of new media studies) to a tipping point where it has the potential not just to facilitate the work of the humanities but to represent the state of the humanities at large in its changing relation to higher education in the postindustrial state. Are the digital humanities up to this larger task?

In his experimental seminar, “Literature: Cross-Disciplinary Models of Literary Interpretation,” Alan Liu asked students to form groups around topics of their choosing and perform analyses using digital tools on their materials. Our group represented four different disciplines and therefore formed around digital tools, rather than content. Each of us took a tool in which we were to become “expert,” and applied that tool to everyone's prepared data. We found that a research focus can form around a set of digital tools even if the objects are not uniform. In this chapter, we discuss how we applied technology to our research goals and collaborative work. We address the main goals of our collaboration, as they emerged through our work together: to explore implications of using digital textual analysis methods on a variety of texts; to uncover possibilities in our datasets through experimentation with different tools; and to recognize the possibility for cross-disciplinary use of the methods we tested. We observed that the tools trend toward certain forms of interpretation and we examine how these trends affect the types of collaboration and analysis possible, but also how they can be re-purposed for alternative approaches. The most important lesson our collaborative experience taught us is that working together both pushed us and liberated us to experiment with our data and methods. In fact, much like our visualizations provide a big picture view of the texts we study, the multidisciplinary nature of our process forced us to step back and view our research at a macro-level. Although our collaboration began as a class project, playing together with technologies led each of us to new and significant understandings of our texts.