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Membrane separation has enjoyed tremendous advances in relevant material and engineering sciences, making it the fastest growing technology in water treatment. Although membranes as a broad-spectrum physical barrier have great advantages over conventional treatment processes in a myriad of applications, the need for higher selectivity and specificity in membrane separation is rising as we move to target contaminants at trace concentrations and to recover valuable chemicals from wastewater with low energy consumption. In this review, we discuss the drivers, fundamental science, and potential enabling materials for high selectivity membranes, as well as their applications in different water treatment processes. Membrane materials and processes that show promise to achieve high selectivity for water, ions, and small molecules—as well as the mechanisms involved—are highlighted. We further identify practical needs, knowledge gaps, and technological barriers in both material development and process design for high selectivity membrane processes. Finally, we discuss research priorities in the context of existing and future water supply paradigms.

Post-treatment of brine produced by reverse osmosis (RO) is a great challenge as it often requires high energy input and works under extreme operating conditions. In this study, brine from a RO plant in El Paso, TX USA was successfully treated using a pilot-scale nanophotonics enhanced solar membrane distillation (NESMD) system. The novel NESMD reactor has a nanophotonic membrane surface area of 0.2 m2 and an internal heat recovery system to recover the latent heat released during vapor condensation. By utilizing a sweeping gas operational mode under real solar irradiation (585–827 W m−2), the NESMD realized successful desalination of RO brine with the membrane flux reaching 0.45–0.65 kg m−2 h−1 and total dissolved solids (TDS) removal greater than 99.5% without an external heat condenser. The decrease in the feed flow rate to the evaporation channel of the NESMD system led to an increase in the gained output ratio (GOR) from 0.35 to 0.62. To the best of our knowledge, this is the largest photothermal reactor utilized for the desalination of real RO brine under practical solar irradiation. Compared with conventional brine treatment processes that require high temperature or pressure, the NESMD desalinates RO brine at near-ambient temperature and pressure with free solar energy, providing a promising approach for water desalination, and RO brine post treatment.

Since the 1970s, The University of Texas at El Paso and El Paso Water have had a synergistic university-utility partnership, and in 2002, we began a sequence of investigations of enhanced recovery of water from silica-saturated reverse osmosis concentrate: (a) two-pass nanofiltration (NF) and reverse osmosis (RO) treatment, (b) lime softening for silica removal, (c) vibratory shear enhanced processing (VSEP), (d) continuous-flow seawater RO treatment of brackish RO concentrate, and finally (e) high-recovery concentrate enhanced-recovery reverse osmosis (CERRO) process. Studies funded by El Paso Water, Texas Water Development Board, U.S. Bureau of Reclamation, and WateReuse Research Foundation were conducted at the Kay Bailey Hutchison (KBH) Plant in El Paso and the Brackish Groundwater National Desalination Research Facility in Alamogordo, NM, and showed that as much as 88% of the water could be recovered from silica-saturated KBH concentrate using the CERRO process. Full-scale implementation of the CERRO process at well sites in El Paso has resulted in 70%-75% recovery of RO concentrate with a specific energy consumption of 1.23 kWh/m3 (4.6 kWh/kgal) and total estimated cost of approximately $0.59/m3 ($2.25/kgal). Cost-effective high-recovery desalination technologies such as CERRO are essential for drought-proof water supply in arid cities such as El Paso. PRACTITIONER POINTS: This two-decade UTEP-EPW research partnership was sustained by a long-term commitment to research and consistent financial support from EPW. Universities can collaborate to leverage utility funding toward larger external grant funding to advance research and development in a win-win partnership. The high-recovery CERRO process was developed through multiple phases of concentrate management research, which would not have been possible without long-term research commitment and risk tolerance from EPW. CERRO systems are being implemented at full scale in El Paso to recover water from silica-saturated RO concentrate at an estimated specific energy consumption of 1.23 kWh/m3 (4.6 kWh/kgal) and total amortized cost of $0.59/m3 ($2.25/kgal).

This article focuses on the adoption and adaptation of methodologies drawn from research in psychology for the evaluation of user response as a manifestation of the mental processes of perception, cognition and emotion. The authors present robust alternative conceptualizations of evaluative methodologies which allow the surfacing of views, feelings and opinions of individual users producing a richer, more informative texture for user centered evaluation of software. This differs from more usual user questionnaire systems such as the Questionnaire of User Interface Satisfaction (QUIS). (Norman et al, 1989) The authors present two different example methodologies so that the reader can firstly, review the methods as a theoretical exercise and secondly, applying similar adaptation principles, derive methods appropriate to their own research or practical context. Copyright © 2010, IGI Global.

The Gemini Multi-conjugate adaptive optics System (GeMS) at the Gemini South telescope in Cerro Pach{\'o}n is the first sodium-based multi-Laser Guide Star (LGS) adaptive optics system. It uses five LGSs and two deformable mirrors to measure and compensate for atmospheric distortions. The GeMS project started in 1999, and saw first light in 2011. It is now in regular operation, producing images close to the diffraction limit in the near infrared, with uniform quality over a field of view of two square arcminutes. The present paper (I) is the first one in a two-paper review of GeMS. It describes the system, explains why and how it was built, discusses the design choices and trade-offs, and presents the main issues encountered during the course of the project. Finally, we briefly present the results of the system first light., Comment: 17 pages, 7 figures, Accepted for publication in MNRAS

The University of Texas at El Paso (UTEP) and the Franklin W. Olin College of Engineering (Olin) are establishing a student-centered hands-on interactive approach to engineering education (similar to Olin's) at UTEP, where it will reside in UTEP's innovative B.S. in Leadership Engineering (LE) program. The goal of the proposed collaboration is to catalyze UTEP's educational innovation through a cross-campus collaboration between the two institutions by incorporating the Olin educational process, both design and features, into the first offerings of the Bachelor of Science in Leadership Engineering (BSLE) program. Specifically, the collaboration includes faculty exchanges between the two institutions; a series of retreats for planning and assessment; curriculum development; and student recruitment practices. The 21st century workplace demands a new engineer - one who effectively contributes to solving problems using innovation, creativity, and strategic foresight. Graduates of the Olin-UTEP developed Bachelor of Science in Leadership Engineering (LE) program will possess these attributes through the program's rigorous yet flexible major in engineering, and in-depth study of leadership and its effect upon technology and society. In this panel we will share the context for our innovative approach, key features of the partnership to date, and acclaim the value of inter-institutional sharing.

The rapid and extensive adoption of Moodle warrants an in-depth evaluation of its users' experience as a key part of determining its suitability as a platform for teaching and learning. This qualitative user experience study considers both user groups of Moodle, staff and students within a large University Faculty of Art & Design and recognizes the relationship between the needs of the two user groups. Whilst both staff and students are successful at completing given tasks in Moodle in our specialist User Lab, many staff were found to display extreme dissatisfaction with the experience. As Moodle use is a one to many relationship, where relatively small numbers of staff operate Moodle for the benefit of scores of students, and as many of the problems observed relate to staff, this impacts on the whole learning experience and environment. Patchy use of Moodle by staff can lead to a student experience that may vary considerably depending on the member of staff teaching them and how well they have integrated the use of Moodle within their course delivery. Word clouds and System Usability Scores (SUS) provide powerful evidence of the gulf between the staff and student user experience.

GeMS, the Gemini Laser Guide Star Multi-Conjugate Adaptive Optics facility system, has seen first light in December 2011, and has already produced images with H band Strehl ratio in excess of 35% over fields of view of 85x85 arcsec, fulfilling the MCAO promise. In this paper, we report on these early results, analyze trends in performance, and concentrate on key or novel aspects of the system, like centroid gain estimation, on-sky non­ common path aberration estimation. We also present the first astrometric analysis, showing very encouraging results.

This chapter focuses on the adoption and adaptation of methodologies drawn from research in psychology for the evaluation of user response as a manifestation of the mental processes of perception, cognition and emotion. We present robust alternative conceptualizations of evaluative methodologies, which allow the surfacing of views, feelings and opinions of individual users producing a richer, more informative texture for user centered evaluation of software. This differs from more usual user questionnaire systems such as the Questionnaire of User Interface Satisfaction (QUIS). We present two different example methodologies so that the reader can firstly, review the methods as a theoretical exercise and secondly, applying similar adaptation principles, derive methods appropriate to their own research or practical context.

Gemini Observatory is using a new approach with instrument software that takes advantage of the strengths of our instrument builders and at the same time better supports our own operational needs. A lightweight software library in conjunction with modern agile software development methodologies is being used to ameliorate the problems encountered with the development of the first and second-generation Gemini instruments. Over the last two years, Gemini and the team constructing the software for the Gemini Planet Imager (GPI) have been using an agile development process to implement the Gemini Instrument Application Interface (GIAPI) and the highlevel control software for the GPI instrument. The GPI is being tested and exercised with the GIAPI, and this has allowed us to perform early end-to-end testing of the instrument software. Early in 2009 for the first time in our development history, we were able to move instrument mechanisms with Gemini software during early instrument construction. As a result of this approach, we discovered and fixed software interface issues between Gemini and GPI. Resolving these problems at this stage is simpler and less expensive than when the full instrument is completed. GPI is currently approaching its integration and testing phase, which will occur in 2010. We expect that utilizing this new approach will yield a more robust software implementation resulting in smoother instrument integration, testing, and commissioning phases. In this paper we describe the key points of our approach and results of applying the new instrument API approach together with agile development methodologies. The paper concludes with lessons learned and suggestions for adapting agile approaches in other astronomy development projects.

The telescope development projects of the 1990's produced a set of capable 8-10m telescopes that are now in operations across the northern and southern hemispheres. This was the first generation of telescopes to benefit from carefully engineered software systems, yet several years of 8m operations have revealed weaknesses in a common architecture employed by many of them. Today engineers are working on the next generation of telescopes, the extremely large telescopes (ELTs), along with their software systems. It is our view that many of the fundamental assumptions about how software systems for 8-m class large telescopes should be constructed are not optimal for the next generation of extremely large telescopes. In fact, these ideas may constrain the solution space and result in overly complex software and increased development costs. This paper points out issues with current architecture solutions and how they impact the software needed for extremely large telescopes. It then provides the outline of a new approach for the design of the software running at the telescope that is targeted towards the development issues of ELTs and large telescope operations.

This research suggests that a novel approach for extending the designers understanding of the user can be found in combining psychological and HCI perspectives. The study examines the users' emotional response to the design of software in Human-Computer Interaction (HCI), the influence it has on their attitudes and expectations of the software, and their motivation to use it. Reference to contemporary theories of human motivation and emotion in psychology, adapted for application to the user at the interface, provide a new `lens' through which to examine the user, and to elicit new data to inform the design process. The exploration of underrepresented variables in humancomputer interaction establishes the basis for additional tools and measures that can be employed by the designer to assess the success, or otherwise, of the user interface. Findings indicate that the opportunity to manage and capitalise on user interaction in the design process is under-recognised.

The key to a successful observing experience at Gemini is a well-prepared science program. The astronomer uses a software application called the Gemini Observing Tool (OT) to fill in the specifics of instrument and telescope configuration during the Phase 2 process. This task involves knowing several details about the Gemini instruments as well as particularities of the telescope and the best way to observe with them. Unfortunately, reviewing these programs can be tedious and error prone. Failure to catch a simple misconfiguration could lead to suboptimal science results or even lost time at the telescope. As part of an effort to make it easier for investigators to define the details of their programs and for the National Gemini Offices and Gemini contact scientists to check and validate them, we have included an automatic program-checking engine in the OT. The "Phase 2 Checker" continually examines the science program configuration as edits are made, finds significant problems, and reports them to the user along with suggested corrections. Since its introduction in the 2007B semester release of the Observing Tool, this feature has been very well received by the community. This paper describes the software (infrastructure and user interface) that supports the Phase 2 Checker, results of validating new and existing science programs, and future improvements we are currently considering.

The Gemini Observatories primarily operate a multi-instrument queue, with observers selecting observations that are best suited to weather and seeing conditions. Queue operations give higher ranked programs a greater chance for completion than lower ranked programs requesting the same conditions and instrument configuration. Queue observing naturally lends itself to Target of Opportunity (ToO) support since the time required to switch between programs and instruments is very short, and the staff observer is trained to operate all the available instruments and modes. Gemini Observatory has supported pre-approved ToO programs since beginning queue operations, and has implemented a rapid (less than 15 minutes response time) ToO mode since 2005. We discuss the ToO procedures, the statistics of 2+ years of rapid ToOs at Gemini North Observatory, the science that this important mode has enabled, and some recent software modifications which have improved both standard and rapid ToO support in the Gemini Observing Tool.

Today's astronomers may use the telescopes and instruments of many observatories to execute their science observations. Discovering the distributed resources that are available is time consuming and error prone because astronomers must manually take facility information and match it to the needs of their science observations. While Phase 1 and Phase 2 of the proposal process are well supported by a wide variety of software tools, the initial phase of discovering what resources are available, Phase 0, suffers from a lack of software support. This paper describes and proposes the creation of a Phase 0 Network to fill this void. The network is built upon peer-to-peer (P2P) technology, showing that this new approach to distributed computing has viable uses in astronomy.

Construction of the first Gemini 8-m telescope is well underway. The software that provides the user interface and high-level control of the observatory, the observatory control system (OCS), is also proceeding on track. The OCS provides tools that assist the astronomer from the proposal submission phase through planning, observation execution, and data review. A capable and flexible software infrastructure is required to support this comprehensive approach. New software technologies and industry standards have played a large part in the implementation of this infrastructure. For instance, the use of CORBA has provided many benefits in the software including object distribution, an interface definition language, and implementation language independence. In this paper, we describe the infrastructure of the OCS that supports observation planning and execution. Important software decisions and interfaces that allow Internet access and the ability to substitute alternate implementations easily are discussed as a model for other similar projects.