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The development of the Keck All sky Precision Adaptive optics (KAPA) project was initiated in September 2018 to upgrade the Keck I adaptive optics (AO) system to enable laser tomography adaptive optics (LTAO) with a four laser guide star (LGS) asterism. The project includes the replacement of the existing LMCT laser with a Toptica laser, the implementation of a new real-time controller (RTC) and wavefront sensor optics and camera, and a new daytime calibration and test platform to provide the required infrastructure for laser tomography. The work presented here describes the new daytime calibration infrastructure to test the performance for the KAPA tomographic algorithms. This paper outlines the hardware infrastructure for daytime calibration and performance assessment of tomographic algorithms. This includes the implementation of an asterism simulator having fiber-coupled light sources simulating four Laser Guide Stars (LGS) and two Natural Guide Stars (NGS) at the AO bench focus, as well as the upgrade of the existing TelSim on the AO bench to simulate focal anisoplanatism and wind driven atmospheric turbulence. A phase screen, that can be adjusted in effective altitude, is used to simulate wind speeds up to 10 m/s for a duration of upto 3 s., Comment: 15 pages, 13 figures. Publishd as part of SPIE Astronomical telescopes + Instrumentation 2022 proceedings

New heat recovery and power targeting models have been developed to evaluate and improve site-wide heat recovery and distribution, and cogeneration systematically. Previous graphical methods for utility system targeting have been proposed based on the assumption of only steam latent heat in the utility system. In this work, a practical graphical approach based on extended site composite curves to quantify site steam targeting has been proposed to provide realistic utility targeting methods, allowing for BFW (boiler feedwater) preheating and steam superheating in steam generation, and steam desuperheating for process heating. Condensate heat recovery from steam usage has also included in the graphical method. A new cogeneration targeting model has been developed including practical limits such as steam mains superheat and turbine exhaust dryness. These new realistic energy and power targeting methods improve the accuracy of the targeting, and overcome the shortcomings of previous targets.

Finding cost effective retrofits for heat exchanger networks remains a challenge. Whilst it is often straightforward to find retrofit changes to an existing network that can improve energy performance, in practice such changes are most often uneconomic. This paper will present an approach to heat exchanger network retrofit around a fixed network structure. Network energy performance is improved through the selective use of heat transfer enhancement. A sensitivity analysis is used to find the most effective heat exchangers to enhance in order to improve the performance of the overall network. The sensitivity analysis used is an extension of a previous sensitivity analysis that was introduced to study network flexibility. The proposed method is applicable for heat exchanger networks involving streams with linear or non-linear physical properties. The enhancement of the most sensitive heat exchangers and avoiding new equipment, together with piping and civil engineering costs, allow much more cost-effective heat exchanger network retrofit.

It is necessary to systematically evaluate site-wide power and heat generation, distribution, and utilization. A new graphical approach based on a Site Grand Composite Curve (SGCC) to targeting cogeneration in site utility systems is proposed to extend Pinch Analysis. The SGCC presents quantitative and visual process targets of heating and cooling requirements, site utility system targets for system steam generation and potential shaft power by steam expansion and condensation. Process indirect heat recovery by intermediate steam levels that can reduce fuel consumption is analyzed readily in the approach. The steam cascade in the SGCC clarifies the Total Site Pinch and site targets of utility very high pressure steam demand and site steam saving. This graphical analysis presents greater clarity for the quantitative interaction between processes and utility system targets than previous approaches. The influence of process variation and steam mains selection on cogeneration improvements is explored much clearer in this straightforward method.

The W. M. Keck Observatory Segment Repair Project is repairing stress-induced fractures near the support points in the primary mirror segments. The cracks are believed to result from deficiencies in the original design and implementation of the adhesive joints connecting the Invar support components to the ZERODUR mirror. Stresses caused by temperature cycling over 20 years of service drove cracks that developed at the glass-metal interfaces. Over the last few years the extent and cause of the cracks have been studied, and new supports have been designed. Repair of the damaged glass required development of specialized tools and procedures for: (1) transport of the segments; (2) pre-repair metrology to establish the initial condition; (3) removal of support hardware assemblies; (4) removal of the original supports; (5) grinding and re-surfacing the damaged glass areas; (6) etching to remove sub-surface damage; (7) bonding new supports; (8) re-installation of support assemblies; and (9) post-repair metrology. Repair of the first segment demonstrated the new tools and processes. On-sky measurements before and after repair verified compliance with the requirements. This paper summarizes the repair process, on-sky results, and transportation system, and also provides an update on the project status and schedule for repairing all 84 mirror segments. Strategies for maintaining quality and ensuring that repairs are done consistently are also presented.

New methods have been developed for the modelling of steam turbines and gas turbines. In particular, the new models give a better description of part-load performance than previously published models. These models have been incorporated, along with those for the other elements of steam systems, into an overall model for utility cogeneration systems. The degrees of freedom of steam systems allow significant opportunity for cost reduction through optimization. This results from the complexity of the interactions within such systems, the continually changing demands on the system and the complexity of cost tariffs for power and fuel. This paper presents improved methods for both the simulation and optimization of utility systems based on the improved models. Using the method presented, significant cost savings can be made by optimizing the system operation at no capital cost. Case studies show a significant potential for cost savings.

Previous graphical methods for utility system targeting have been developed to address the targets achieved only when the steam is saturated. This work has developed new graphical methods to improve the accuracy of the targeting by including important practical considerations. Steam Composite Profiles are constructed firstly including boiler feedwater (BFW) preheating, steam generation at the saturation temperature, and steam superheating for steam generation. Site Source-Sink Profiles and Site Grand Composite Curves are plotted to target realistic boiler steam demand, the desuperheated steam for process heating, steam generation from the process heat recovery, and steam saving due to process indirect heat recovery through steam mains. These new energy targeting have been applied to overcome the shortcomings of previous methods ignoring the heat of BFW preheating and steam superheating in steam generation, and allows practical quantitative analysis combined with conceptual insights.

This paper presents a new method for targeting maximum water reuse in processing systems. Two cases are considered. In the first case, the mass transfer is modelled in terms of a fixed mass load. This leads to a problem which can be solved as a non-linear optimization problem. In the second case, the mass transfer is modelled in terms of a fixed outlet concentration. This leads to a problem which can be solved as a linear optimization problem. In practice, many water-using operations will call for the mass exchange characteristics of some contaminants to be modelled by fixed mass load and others to be modelled by fixed outlet concentration, leading overall to a non-linear problem. To overcome the difficulties associated with non-linear optimization, a combined approach is presented in which the linearmodel is used to provide an initialization for non-linear optimization.The new method has also been combined with a previously published graphical approach to provide a representation which incorporates all constraints, not only concentration, but also flowrate constraints and forbidden matches, etc.

With the much anticipated delivery of the Lockheed Martin Coherent Technology Quasi-CW laser, the W. M. Keck Observatory was able to complete the installation and integration of the Laser Guide Star Adaptive Optics System on the Keck I telescope. The Keck I LGSAO system was developed to provide redundancy for the Keck II system as well as balancing the instrumentation load between the two telescopes and interferometers. With the improved sodium coupling efficiency of the laser and a center launching system, the Keck I laser performance is expected to exceed those on the Keck II system. We present the challenges of integrating the Keck I Laser Guide Star Adaptive Optics System on an operational telescope. We will present issues and performance data related to the primary subsystem components such as the laser itself, the Selex Galileo Avionica launch telescope, the Mitsubishi fiber transport, and the Adaptive Optics System. The paper will also focus on the integration and testing performed at the W. M. Keck headquarters as well as the summit of Mauna Kea. We will present initial first light performance of the Keck I LGSAO System and compare those to the existing Keck II LGSAO System.

The Laser Guide Star Adaptive Optics (LGS AO) at the W.M. Keck Observatory is the first system of its kind being used to conduct routine science on a ten-meter telescope. In 2005, more than fifty nights of LGSAO science and engineering were carried out using the NIRC2 and OSIRIS science instruments. In this paper, we report on the typical performance and operations of its LGS AO-specific sub-systems (laser, tip-tilt sensor, low-bandwidth wavefront sensor) as well as the overall scientific performance and observing efficiency. We conclude the paper by describing our main performance limitations and present possible developments to overcome them.

The paper describes the advantages of Lithography for quality reproduction at high production speeds by comparison with other digital printing systems. The claim is made that silver halide offers the best and most flexible technology for CTP and that the use of the single sheet diffusion transfer method offers the most elegant, simple and therefore the most practical of solutions to the problem of providing Silver halide photographic properties on a litho printing plate. The changes in litho plate technology are briefly reviewed, the specific requirements of computer to plate are outlined and then the application of single sheet silver halide diffusion transfer technology to computer to plate (CTP) are described in more detail. A representative sample of output recorders (platesetters) are described and some possible technology routes for higher speed and lower cost are reported.© (1995) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

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