BILSAT: Advancing Smallsat Capabilities

Small spacecraft technologies and capabilities are evolving to the point where the BILSAT 120kg spacecraft will this year demonstrate capabilities and performance similar to the 320kg UoSAT-12 mission launched in 1999. Over the past few years, the design of small satellites has evolved from simple curiosities to effective, high performance systems, capable of competing with much bigger and much more expensive spacecraft. Within the framework of an agreement between SSTL and TUBITAK-BILTEN (The Information Technologies and Electronics Research Institute), a non-profit government laboratory located in Ankara, Turkey, a Technology Transfer Program was started in August 2001. This program includes the design, manufacture and launch of one Enhanced SSTL microsatellite platform, one engineering model for use in Turkey and the training of engineers in all aspects of the spacecraft design. Detailed design began using the Enhanced SSTL microsatellite platform as the starting point. The end product that will be launched in the summer of 2003, is the most advanced spacecraft ever designed by SSTL, carrying two advanced payloads developed by TUBITAK-BILTEN. The spacecraft is a highly optimised satellite, with a mass of 120kg and including 14 cameras (in several imager arrangements), a 10m/s class resistojet propulsion system, VHF/UHF and S-band RF systems, tried and tested OBDH units in parallel with newly designed mass data storage and processing units, all this topped by a high performance AODCS subsystem, including two star trackers, GPS receiver (for both orbit and attitude determination), rate gyros, four momentum/reaction wheels, and what will be the first operational use of Control Momentum Gyros on a small spacecraft, to perform high agility manoeuvres. These units will be used to achieve the missions specified for this project, mainly full imaging of Turkey, stereoscopic imaging of selected targets, a Digital Elevation Map of Turkey, and communications. The present paper discusses briefly the technical characteristics of the spacecraft, but focuses on the mission aspects and how the different subsystems (namely the new subsystems and payloads) will be used to accomplish the mission. The operational modes of the spacecraft are discussed and the interaction of the AODCS subsystem with the OBDH and Imaging system is described in detail

Prospectus, February 7, 1979

VETERANS AT PARKLAND; Student suggests how to resell books; Could Pc King be solution for apathy?; Carry supplies for winter road dangers; Prospectus… It\u27s a start; PBDT appearing at Parkland; Divorce discussed; Womens forum to meet Tues.; Remedy is available; Speakers Bureau sponsored by Parkland Womens Program; Speech synthesizer to be finished soon; PC singers seeking help; Fewer part-time students at PC; Workshop to be at PC Feb. 17; Student Elections; Canteen increases food prices at PC; Two Parkland veterans tell their stories; PC veterans receive answers; PC rockers lead a double life; PC could be underfunded; New group gets mixed reactions; Classifieds; PC Womens Program gives weekly workshops; WPCD\u27s Hit List for the week of Feb. 5; Ag-business seminars; PCD schedules health program; Creative writing class is now PC radio series; Cobras lose two in weekend play; Track win big in Chicago, look toward region meethttps://spark.parkland.edu/prospectus_1979/1027/thumbnail.jp

A whole system approach to increasing children’s physical activity in a multi-ethnic UK city:a process evaluation protocol

BACKGROUND: Engaging in regular physical activity requires continued complex decision-making in varied and dynamic individual, social and structural contexts. Widespread shortfalls of physical activity interventions suggests the complex underlying mechanisms of change are not yet fully understood. More insightful process evaluations are needed to design and implement more effective approaches. This paper describes the protocol for a process evaluation of the JU:MP programme, a whole systems approach to increasing physical activity in children and young people aged 5–14 years in North Bradford, UK. METHODS: This process evaluation, underpinned by realist philosophy, aims to understand the development and implementation of the JU:MP programme and the mechanisms by which JU:MP influences physical activity in children and young people. It also aims to explore behaviour change across wider policy, strategy and neighbourhood systems. A mixed method data collection approach will include semi-structured interview, observation, documentary analysis, surveys, and participatory evaluation methods including reflections and ripple effect mapping. DISCUSSION: This protocol offers an innovative approach on the use of process evaluation feeding into an iterative programme intended to generate evidence-based practice and deliver practice-based evidence. This paper advances knowledge regarding the development of process evaluations for evaluating systems interventions, and emphasises the importance of process evaluation. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12889-021-12255-w

Wavefront controls for a large submillimeter-wave observatory

The 25-m aperture Cornell Caltech Atacama Telescope (CCAT) will have a primary mirror that is divided into 162 individual segments, each of which is equipped with 3 positioning actuators. This paper presents a mathematical description of the telescope, its actuators and sensors, and uses it to derive control laws for figure maintenance. A Kalman Filter-based Optical State Estimator is used to continuously estimate the aberrations of the telescope; these are used in a state-feedback controller to maintain image quality. This approach provides the means to correct for the optical effects of errors that occur in un-actuated degrees of freedom, such as lateral translations of the segments. The control laws are exercised in Monte Carlo and simulation analysis, to bound the closed-loop performance of the telescope and to conduct control design trades

Modeling a large submillimeter-wave observatory

The 25 meter aperture Cornell Caltech Atacama Telescope (CCAT) will provide an enormous increase in sensitivity in the submillimeter bands compared to existing observatories, provided it can establish and maintain excellent image quality. To accomplish this at a very low cost, it is necessary to conduct accurate engineering trades, including the most effective segment and wavefront sensing and control approach, to determine the best method for continuously maintaining wavefront quality in the operational environment. We describe an integrated structural/optical/controls model that provides accurate performance prediction. We also detail the analysis methods used to quantify critical design trades

The Grizzly, February 22, 2000

Black History Celebrated Across Ursinus Campus • Greeks Fall Under Scrutiny • Arts Program to Expand at UC • Nobel Laureate Lecture Draws Positive Student Response • Littleton, Letterman and the South Carolina Primary • After South Carolina: Can McCain be the Man for the GOP? • Pledging Debate Continues: The Problem of Hazing • Pat McGee: Pseudo DMB? • Valentine\u27s Day Blues • Tumbling and Dancing with Words • Music Review: Dr. John • Glah, Druckenmiller Shine at CC Swimming Championships • UC Wrestling Falls Short in Centennial Championships • UC Spring Sports Preview • Gymnastics Trounces School Record at Marranca Invitational • Men\u27s Basketball Ends Stellar Season • Sports Profile: Christopher Ciuncihttps://digitalcommons.ursinus.edu/grizzlynews/1460/thumbnail.jp

The Grizzly, February 15, 2000

UC Students Debate Pros, Cons of Pledging On Campus • Feelings of Brotherhood, Sisterhood Prevalent During Pledging Process • Employment Available for Graduating Seniors • True Love: Sorrow and Devotion • Hackers, Hijackers, and the Wide World of Sports • The Greeks Agree: Pledges Have no Free Will • Pledging: What\u27s the Big Deal Anyway? • muMs Schemes at Ursinus • Pat McGee to Jam at Ursinus • Music Review: The Alligator Blues Band • Gymnastics Tops RIC with Season High Score • Intramural 3 on 3 Action: Brains vs. Brute • Indoor Track Steps Up to Eight Way Challenge • Ursinus Wrestling Battles for 4-1 • Sports Profile: Shana Goanehttps://digitalcommons.ursinus.edu/grizzlynews/1459/thumbnail.jp

Comparing nuclear power trajectories in Germany and the UK: from ‘regimes' to ‘democracies’ in sociotechnical transitions and Discontinuities

This paper focuses on arguably the single most striking contrast in contemporary major energy politics in Europe (and even the developed world as a whole): the starkly differing civil nuclear policies of Germany and the UK. Germany is seeking entirely to phase out nuclear power by 2022. Yet the UK advocates a ‘nuclear renaissance’, promoting the most ambitious new nuclear construction programme in Western Europe.Here,this paper poses a simple yet quite fundamental question: what are the particular divergent conditions most strongly implicated in the contrasting developments in these two countries. With nuclear playing such an iconic role in historical discussions over technological continuity and transformation, answering this may assist in wider understandings of sociotechnical incumbency and discontinuity in the burgeoning field of‘sustainability transitions’. To this end, an ‘abductive’ approach is taken: deploying nine potentially relevant criteria for understanding the different directions pursued in Germany and the UK. Together constituted by 30 parameters spanning literatures related to socio-technical regimes in general as well as nuclear technology in particular, the criteria are divided into those that are ‘internal’ and ‘external’ to the ‘focal regime configuration’ of nuclear power and associated ‘challenger technologies’ like renewables. It is ‘internal’ criteria that are emphasised in conventional sociotechnical regime theory, with ‘external’ criteria relatively less well explored. Asking under each criterion whether attempted discontinuation of nuclear power would be more likely in Germany or the UK, a clear picture emerges. ‘Internal’ criteria suggest attempted nuclear discontinuation should be more likely in the UK than in Germany– the reverse of what is occurring. ‘External’ criteria are more aligned with observed dynamics –especially those relating to military nuclear commitments and broader ‘qualities of democracy’. Despite many differences of framing concerning exactly what constitutes ‘democracy’, a rich political science literature on this point is unanimous in characterising Germany more positively than the UK. Although based only on a single case,a potentially important question is nonetheless raised as to whether sociotechnical regime theory might usefully give greater attention to the general importance of various aspects of democracy in constituting conditions for significant technological discontinuities and transformations. If so, the policy implications are significant. A number of important areas are identified for future research, including the roles of diverse understandings and specific aspects of democracy and the particular relevance of military nuclear commitments– whose under-discussion in civil nuclear policy literatures raises its own questions of democratic accountability

Synergistic Effect of SRY and Its Direct Target, WDR5, on Sox9 Expression

SRY is a sex-determining gene that encodes a transcription factor, which triggers male development in most mammals. The molecular mechanism of SRY action in testis determination is, however, poorly understood. In this study, we demonstrate that WDR5, which encodes a WD-40 repeat protein, is a direct target of SRY. EMSA experiments and ChIP assays showed that SRY could bind to the WDR5 gene promoter directly. Overexpression of SRY in LNCaP cells significantly increased WDR5 expression concurrent with histone H3K4 methylation on the WDR5 promoter. To specifically address whether SRY contributes to WDR5 regulation, we introduced a 4-hydroxy-tamoxifen-inducible SRY allele into LNCaP cells. Conditional SRY expression triggered enrichment of SRY on the WDR5 promoter resulting in induction of WDR5 transcription. We found that WDR5 was self regulating through a positive feedback loop. WDR5 and SRY interacted and were colocalized in cells. In addition, the interaction of WDR5 with SRY resulted in activation of Sox9 while repressing the expression of β-catenin. These results suggest that, in conjunction with SRY, WDR5 plays an important role in sex determination

Loss of Mitogen-Activated Protein Kinase Kinase Kinase 4 (MAP3K4) Reveals a Requirement for MAPK Signalling in Mouse Sex Determination

The boygirl (byg) mouse mutant reveals that MAP3K4-mediated signaling is necessary for normal SRY expression and testis specification in the developing mouse gonad