Field evaluation of ocean wave measurements with GPS buoys

An intercomparison of Datawell accelerometer buoys, Datawell GPS buoys, and prototype GPS buoys was conducted to determine the viability of using off-the-shelf GPS receivers to measure ocean surface waves. In the experiment, conducted off the coast of California near Bodega Bay, clusters off Datawell and prototype GPS buoys were deployed to collect ocean surface wave measurements. The first phase of the research was an intercomparison of wave measurements from a Datawell accelerometer sensor, the Magellan MMCX GPS receiver and the GlobalSat MR-350 GPS receiver. The Datawell accelerometer and the Magellan MMCX receiver measurements of both vertical and horizontal wave orbital excursions are in good agreement. The GlobalSat MR-350 receiver also accurately resolved horizontal wave orbital displacements but failed to reproduce the vertical wave excursion measurement by the accelerometer sensors. The second phase of the project was an independent intercomparison between the Datawell MK-II accelerometer buoys, Datawell Waverider GPS buoys, and the prototype GPS buoys built by the NPS team using the Magellan MMCX receiver. The intercomparison showed good agreement between the off-the-shelf GPS buoys, the newer Datawell GPS buoys as well as the traditional Datawell accelerometer buoys in the energetic part of the wave spectrum.http://archive.org/details/fieldevaluationo109455117US Navy (USN) authorApproved for public release; distribution is unlimited

A Quantitative Phenomenological Study of the Proliferated Use of Electronics and the Impact on the Communication Skills of Prekindergartens

Children who have a deficit in language as they enter school continue to be behind their peers as they progress from grade to grade. During the COVID-19 pandemic, many children were unable to attend school or preschool in person. Children develop language best in face-to-face environments. Previous literature did not include how the pandemic and the increased use of remote learning using technology might impact kindergarten readiness. This study adds to the body of knowledge by including perceptions of parents after remote learning during the COVID-19 pandemic. I utilized a quantitative phenomenological research design. Data were collected using a questionnaire survey that used a 5-point Likert scale. The questions determined the perceptions of parents of kindergarten students on (a) what parents of kindergarteners believe they did to prepare their children before kindergarten, (b) what skills parents of kindergarten students feel are important for success in kindergarten, and (c) how participation in remote learning change how parents feel they should have prepared their children for kindergarten. Results of the study indicate that parents did change their overall perceptions of what they felt were the most important skills for students to be prepared to know as they enter kindergarten. Before the pandemic and remote learning, parents felt that cognitive and motor were most important and that social/emotional was the most important measure of success in kindergarten. Following remote instruction, 48% of parents in the sample population, stated they would do more to prepare their children in language/ communication

Dealing with rogue virtual machines in a cloud services environment

In current cloud services hosting solutions, various mechanisms have been developed to minimize the possibility of hosting staff from breaching security. However, while functions such as replicating and moving machines are legitimate actions in clouds, we show that there are risks in administrators being able to perform them. We describe three threat scenarios related to hosting staff on the cloud architecture and indicate how an appropriate accountability architecture can mitigate these risks in the sense that the attacks can be detected and the perpetrators identified. We identify requirements and future research and development needed to protect cloud service environments from these attacks

Mystery of the Lyα Blobs

We present Spitzer Space Telescope observations of the extended Lyman α blobs associated with the z=2.38 over-density J2143-4423, the largest known structure (110 Mpc) above z=2. We detect all 4 of the Lyα blobs in all four IRAC channels and we also detect 3 out of 4 of the blobs with MIPS 24μm. Conversion from rest-wavelength 7μm to total far-infrared luminosity using locally derived correlations suggests all the detected sources are in the class of ULIRGs or even Hyper-LIRGs. We find a weak correlation between Lyα and mid-infrared emission for the Lyα blobs (L_(Lyα)/L_(bol) = 0.05-0.2%). Nearly all Lyα blobs show some evidence for interaction, either in HST imaging, or the proximity of multiple MIPS sources within the Lyα cloud. This suggests that interaction or even mergers may be related to the production of Lyα blobs. Optical through infrared SEDs of the Lyα blobs do not show a clear 1.6μm bump, but rather are indicative of a composite of star formation and AGN energy sources

Adolescent Dating Violence Prevention and Intervention in a Community Setting: Perspectives of Young Adults and Professionals

Adolescent dating violence (ADV) is a significant community problem. In this study, we examine the perspectives of two groups (young adults who experienced ADV as teens and professionals who work with teens) on ADV prevention/intervention in a community context. We interviewed 88 young adults and 20 professionals. Our research team used Thorne’s (2008) interpretive description methods to determine participants’ perspectives on community views on ADV, community ADV prevention/intervention programs, and ideal ADV prevention/intervention strategies. Participants perceived most communities as being blind to ADV. They perceived prevention programs as unavailable, inappropriate, or impersonal. Young adults indicated that professionals should use a gradual approach with teens experiencing ADV. Participants suggested that ideal prevention programs should include personal development and education. Helping professionals can use these findings to develop effective community-based ADV prevention/intervention program

Hydrogen adsorption and cohesive energy of single-walled carbon nanotubes

Hydrogen adsorption on crystalline ropes of carbon single-walled nanotubes (SWNT) was found to exceed 8 wt.%, which is the highest capacity of any carbon material. Hydrogen is first adsorbed on the outer surfaces of the crystalline ropes. At pressures higher than about 40 bar at 80 K, however, a phase transition occurs where there is a separation of the individual SWNTs, and hydrogen is physisorbed on their exposed surfaces. The pressure of this phase transition provides a tube-tube cohesive energy for much of the material of 5 meV/C atom. This small cohesive energy is affected strongly by the quality of crystalline order in the ropes

Far-ultraviolet imaging of the Hubble Deep Field-North: Star formation in normal galaxies at z < 1

We present far-ultraviolet (FUV) imaging of the Hubble Deep Field-North (HDF-N) taken with the Solar Blind Channel of the Advanced Camera for Surveys (ACS SBC) and the FUV MAMA detector of the Space Telescope Imaging Spectrograph onboard the Hubble Space Telescope. The full WFPC2 deep field has been observed at 1600 Å. We detect 134 galaxies and one star down to a limit of FUV_(AB) ~ 29. All sources have counterparts in the WFPC2 image. Redshifts (spectroscopic or photometric) for the detected sources are in the range 0 < z < 1. We find that the FUV galaxy number counts are higher than those reported by GALEX, which we attribute at least in part to cosmic variance in the small HDF-N field of view. Six of the 13 Chandra sources at z < 0.85 in the HDF-N are detected in the FUV, and those are consistent with starbursts rather than active galactic nuclei. Cross-correlating with Spitzer sources in the field, we find that the FUV detections show general agreement with the expected L_(IR)/L_(UV) versus β relationship. We infer star formation rates (SFRs), corrected for extinction using the UV slope, and find a median value of 0.3 M_☉ yr^(-1) for FUV-detected galaxies, with 75% of detected sources having SFR < 1 M_☉ yr^(-1). Examining the morphological distribution of sources, we find that about half of all FUV-detected sources are identified as spiral galaxies. Half of morphologically selected spheroid galaxies at z < 0.85 are detected in the FUV, suggesting that such sources have had significant ongoing star formation in the epoch since z ~ 1

The Mid-Infrared Instrument for the James Webb Space Telescope, VIII: The MIRI Focal Plane System

We describe the layout and unique features of the focal plane system for MIRI. We begin with the detector array and its readout integrated circuit (combining the amplifier unit cells and the multiplexer), the electronics, and the steps by which the data collection is controlled and the output signals are digitized and delivered to the JWST spacecraft electronics system. We then discuss the operation of this MIRI data system, including detector readout patterns, operation of subarrays, and data formats. Finally, we summarize the performance of the system, including remaining anomalies that need to be corrected in the data pipeline

A First Estimate Of The X-Ray Binary Frequency As A Function Of Star Cluster Mass In A Single Galactic System

We use the previously-identified 15 infrared star-cluster counterparts to X-ray point sources in the interacting galaxies NGC 4038/4039 (the Antennae) to study the relationship between total cluster mass and X-ray binary number. This significant population of X-Ray/IR associations allows us to perform, for the first time, a statistical study of X-ray point sources and their environments. We define a quantity, \eta, relating the fraction of X-ray sources per unit mass as a function of cluster mass in the Antennae. We compute cluster mass by fitting spectral evolutionary models to K_s luminosity. Considering that this method depends on cluster age, we use four different age distributions to explore the effects of cluster age on the value of \eta and find it varies by less than a factor of four. We find a mean value of \eta for these different distributions of \eta = 1.7 x 10^-8 M_\sun^-1 with \sigma_\eta = 1.2 x 10^-8 M_\sun^-1. Performing a \chi^2 test, we demonstrate \eta could exhibit a positive slope, but that it depends on the assumed distribution in cluster ages. While the estimated uncertainties in \eta are factors of a few, we believe this is the first estimate made of this quantity to ``order of magnitude'' accuracy. We also compare our findings to theoretical models of open and globular cluster evolution, incorporating the X-ray binary fraction per cluster.Comment: 20 pages, 6 figures, accepted by Ap