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Projects rarely go according to plan, but this is especially true of those that involve multiple institutions and have a significant degree of complexity associated with them. This work relates the experiences an Advanced Technological Education (ATE) project around high value manufacturing. The project was a collaboration with a Texas A&M University and Houston Community College. The project comprised three main aspects: 1) the development of a certificate program in high value manufacturing; 2) offering professional development to working professionals in the area of high value manufacturing; and 3) educating teachers about advanced manufacturing with a goal of recruiting their students into manufacturing careers. This work describes the lessons learned through each of the project aspects. The design of the High Value Manufacturing Certificate Program required close collaboration between both institutions. The issues that arose during this development process included personnel turnover, approval timelines and processes, and agreement on the course content. The authors will relay how they navigated these issues to get the program created and approved. The creation of the professional development program did not involve the community college directly, but was very dependent on recruiting participants. This recruitment proved to be more difficult than the project team expected. The targeting of the professional development program and the development of the curriculum will be discussed. The authors will also highlight the delivery changes they implemented over the two years of the offerings based on participant feedback. The final aspect of the project is the teacher experience with advanced manufacturing. Hosting teachings and determining what content and activities they experience is a somewhat daunting task. The use of an existing University Program and the selection of collaborating faculty will be discussed. Overall, the lessons learned from this project can be an opportunity for new ATE principal investigators (PIs) to learn from the authors’ experiences. It can also help potential ATE PIs craft more realistic and practical proposals. 

Research shows that there is a growing need for skilled workers in the area of advanced manufacturing; this refers to making use of new technologies and advanced processes to produce products that have high value. More importantly, U.S. government employment data reveals that there is lack of supply of skilled workers in the manufacturing sector. Furthermore, it has also been widely cited in industrial literature that there is a concern regarding the job readiness of fresh college graduates and the gaps in skills sets needed to be successful in an industrial setting, especially in the engineering or manufacturing fields. One approach to bridge the skills gap is to provide customized continuing education to current the workforce as per the industry need. This paper presents a case study of such customized continuing education offered by Texas A&M University for oil and gas industry in Houston, Texas. Specifically, as a part of National Science Foundation Advanced Technological Education project, two professional development sessions were organized in the summer of 2018 in Houston targeting the energy industry. Both programs were two-days long and focused on two key aspects of high value manufacturing: manufacturing operations excellence and manufacturing quality excellence. The professional development sessions were focused on materials and inventory planning, production economics, manufacturing quality, non-destructive evaluation, statistical process control, and lean/ sixsigma. The continuing education programs and course materials were developed based on the feedback from the industry advisory board for the Manufacturing Center of Excellence at Houston Community College, which is a collaborating partner on the ATE Grant. As a part of assessment of the programs, industry participants in the both sessions were given comprehensive surveys asking for their feedback on the applicability of the educational sessions. Overall, the participants rated the sessions very highly on the organization and the relevancy of the program topics and learning materials. The participants also felt that they learned new information through these programs. 

The imaging fidelity of the Event Horizon Telescope (EHT) is currently determined by its sparse baseline coverage. In particular, EHT coverage is dominated by long baselines, and is highly sensitive to atmospheric conditions and loss of sites between experiments. The limited short/mid-range baselines especially affect the imaging process, hindering the recovery of more extended features in the image. We present an algorithmic contingency for the absence of well-constrained short baselines in the imaging of compact sources, such as the supermassive black holes observed with the EHT. This technique enforces a specific second moment on the reconstructed image in the form of a size constraint, which corresponds to the curvature of the measured visibility function at zero baseline. The method enables the recovery of information lost in gaps of the baseline coverage on short baselines and enables corrections of any systematic amplitude offsets for the stations giving short-baseline measurements present in the observation. The regularization can use historical source size measurements to constrain the second moment of the reconstructed image to match the observed size. We additionally show that a characteristic size can be derived from available short-baseline measurements, extrapolated from other wavelengths, or estimated without complementary size constraints with parameter searches. We demonstrate the capabilities of this method for both static and movie reconstructions of variable sources. 

Context.3C 84 is a nearby radio source with a complex total intensity structure, showing linear polarisation and spectral patterns. A detailed investigation of the central engine region necessitates the use of very-long-baseline interferometry (VLBI) above the hitherto available maximum frequency of 86 GHz.

Aims.Using ultrahigh resolution VLBI observations at the currently highest available frequency of 228 GHz, we aim to perform a direct detection of compact structures and understand the physical conditions in the compact region of 3C 84.

Methods.We used Event Horizon Telescope (EHT) 228 GHz observations and, given the limited (u, v)-coverage, applied geometric model fitting to the data. Furthermore, we employed quasi-simultaneously observed, ancillary multi-frequency VLBI data for the source in order to carry out a comprehensive analysis of the core structure.

Results.We report the detection of a highly ordered, strong magnetic field around the central, supermassive black hole of 3C 84. The brightness temperature analysis suggests that the system is in equipartition. We also determined a turnover frequency ofν_m = (113 ± 4) GHz, a corresponding synchrotron self-absorbed magnetic field ofB_SSA = (2.9 ± 1.6) G, and an equipartition magnetic field ofB_eq = (5.2 ± 0.6) G. Three components are resolved with the highest fractional polarisation detected for this object (m_net = (17.0 ± 3.9)%). The positions of the components are compatible with those seen in low-frequency VLBI observations since 2017–2018. We report a steeply negative slope of the spectrum at 228 GHz. We used these findings to test existing models of jet formation, propagation, and Faraday rotation in 3C 84.

Conclusions.The findings of our investigation into different flow geometries and black hole spins support an advection-dominated accretion flow in a magnetically arrested state around a rapidly rotating supermassive black hole as a model of the jet-launching system in the core of 3C 84. However, systematic uncertainties due to the limited (u, v)-coverage, however, cannot be ignored. Our upcoming work using new EHT data, which offer full imaging capabilities, will shed more light on the compact region of 3C 84.

 

Abstract We present the second public data release (DR2) from the DECam Local Volume Exploration survey (DELVE). DELVE DR2 combines new DECam observations with archival DECam data from the Dark Energy Survey, the DECam Legacy Survey, and other DECam community programs. DELVE DR2 consists of ∼160,000 exposures that cover >21,000 deg 2 of the high-Galactic-latitude (∣ b ∣ > 10°) sky in four broadband optical/near-infrared filters ( g , r , i , z ). DELVE DR2 provides point-source and automatic aperture photometry for ∼2.5 billion astronomical sources with a median 5 σ point-source depth of g = 24.3, r = 23.9, i = 23.5, and z = 22.8 mag. A region of ∼17,000 deg 2 has been imaged in all four filters, providing four-band photometric measurements for ∼618 million astronomical sources. DELVE DR2 covers more than 4 times the area of the previous DELVE data release and contains roughly 5 times as many astronomical objects. DELVE DR2 is publicly available via the NOIRLab Astro Data Lab science platform.