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This paper presents a novel method for verifying interfaces and generating interface control documents (ICDs) from a system model in SysMLTM. In systems and software engineering, ICDs are key artifacts that specify the interface(s) to a system or subsystem, and are used to control the documentation of these interfaces. ICDs enable independent teams to develop connecting systems that use the specified interfaces. In the context of the Thirty Meter Telescope (TMT), interface control documents also act as contracts for delivered subsystems. The Alignment and Phasing system (APS) is one such subsystem. APS is required to implement a particular interface, and formulates requirements for the interfaces to be provided by other components of TMT that interface with APS. As the design of APS matures, these interfaces are frequently refined, making it necessary for related ICDs to be updated. In current systems engineering practice, ICDs are maintained manually. This manual maintenance can lead to a loss in integrity and accuracy of the documents over time, resulting in the documents no longer reflecting the actual state of the interfaces of a system. We show how a system model in SysMLTM can be used to generate ICDs automatically. The method is demonstrated through application to interface control documents pertaining to APS. Specifically, we apply the method to the interface of APS to the primary mirror control system (M1CS) and of APS to the Telescope Control System (TCS). We evaluate the newly introduced method through application to two case studies.

An acute dry cough results commonly from bronchitis or pneumonia. When a patient presents with signs of infection, respiratory crackles, and a positive chest radiograph, the diagnosis of pneumonia is more common. Antibiotic failure in a patient being treated for community-acquired pneumonia requires further investigation through chest computed tomography. If a lung mass is found on chest computed tomography, lung empyema, abscess, and cancer need to be included on the differential and managed aggressively. This report describes a 55-year-old Caucasian male, with a history of obesity, recovered alcoholism, hypercholesterolemia, and hypertension, presenting with an acute dry cough in the primary care setting. The patient developed signs of infection and was found to have a lung mass on chest computed tomography. Treatment with piperacillin-tazobactam and chest tube placement did not resolve the mass, so treatment with thoracotomy and lobectomy was required. It was determined through surgical investigation that the patient, despite having no risk factors, developed a lung abscess. Lung abscesses rarely form in healthy middle-aged individuals making it an unlikely cause of the patient's presenting symptom, dry cough. The patient cleared his infection with proper management and only suffered minor complications of mild pneumoperitoneum and pneumothorax during his hospitalization.

RNA-Seq is the leading technology for analyzing gene expression on a global scale across a broad spectrum of sample types. However, due to chemical modifications by fixation or degradation due to collection methods, samples often contain an abundance of RNA that is no longer intact, and the capability of current RNA-Seq protocols to accurately quantify such samples is often limited. We have developed an RNA-Seq protocol to address these key issues as well as quantify gene expression from the whole transcriptome. Furthermore, for compatibility with improved sequencing platforms, we use restructured adapter sequences to generate libraries for Illumina HiSeq, MiSeq, and NextSeq platforms. Our protocol utilizes duplex-specific nuclease (DSN) to remove abundant ribosomal RNA sequences while retaining other types of RNA for superior transcriptome profiling from low quantity input. We employ the Illumina sequencing platform, but this method is described in sufficient detail to adapt to other platforms.

The primary, secondary and tertiary mirrors of the Thirty Meter Telescope (TMT), taken together, have approximately 12,000 degrees of freedom in optical alignment. The Alignment and Phasing System (APS) will use starlight and a variety of Shack-Hartmann based measurement techniques to position the segment pistons, tips, and tilts, segment figures, secondary rigid body motion, secondary figure and the tertiary figure to correctly align the TMT. We present a conceptual design of the APS including the requirements, alignment modes, predicted performance, software architecture, and an optical design.

The Army is developing new gelled bipropellants and tactical missile propulsion systems that utilize these propellants for both current and future combat systems. The use of hypergolic gel propellants introduces new challenges in combustion control. A major challenge is mixing the oxidizer and fuel to obtain maximum performance from the combustor without increasing the size of the engine. The impinging stream vortex engine, ISVE, offers an alternative to increasing the volume of the combustion c hambers and has already generated excellent performance test data. Bipropellant injecti on in the ISVE occurs along the azimuthal wall of the combustion chamber. In addition, a novel modification has been proposed in which the propellant is injected in a stage d fashion to tailor hypergolic ignition. This concept, termed SLAMMITT (Sliding Actuator Multi-Mode Injection Throttling Technique), is currently being tested at the AMRDEC. Since the ISVE and SLAMMITT are new concepts, data and analytical models relating performanc e to engine design parameters are scarce. Since the bipropellant injection procedu re used for the ISVE and SLAMMITT do not follow the convention of the “showerhead” type, i.e. injection at the top or head-end of the engine, classical models do not yield useful re sults. In order to fully exploit the performance advantages that have been realized for the ISVE, it is desirable to understand the underlying flow physics of the engine with the SLAM MITT modification. The Army Research Laboratory (ARL) has developed a time-accurate computational fluid dynamics (CFD) code, ARL-NSRG3, which includes high-temperature thermodynamics, variable specific heats and transport properties, and finite-rate chemical kinetics. This paper is the most recent in a series of papers that describes effo rts to utilize modern CFD, combined with high-performance computers, to reveal gas dynamics and combustion patterns as well as predict chamber pressure and thrust levels in the ISVE including the effects of staged injection.

The Army is developing new gelled bipropellants and tactical missile propulsion systems that utilize these propellants for both current and future combat systems. The use of hypergolic gel propellants introduces new challenges in combustion control. A major challenge is mixing the oxidizer and fuel to obtain maximum performance from the combustor without increasing the size of the engine. The impinging stream vortex engine, ISVE, offers an alternative to increasing the volume of the combustion chambers and has already generated excellent performance test data. Bipropellant injection in the ISVE occurs along the azimuthal wall of the combustion chamber. In addition, a novel modification has been proposed in which the propellant is injected in a staged fashion to tailor hypergolic ignition. This concept, termed SLAMMITT (Sliding Actuator Multi-Mode Injection Throttling Technique), is currently being tested at the AMRDEC. Since the ISVE and SLAMMITT are new concepts, data and analytical models relating performance to engine design parameters are scarce. Since the bipropellant injection procedure used for the ISVE and SLAMMITT do not follow the convention of the “showerhead” type, i.e. injection at the top or head-end of the engine, classical models do not yield useful results. In order to fully exploit the performance advantages that have been realized for the ISVE, it is desirable to understand the underlying flow physics of the engine with the SLAMMITT modification. The Army Research Laboratory (ARL) has developed a time-accurate computational fluid dynamics (CFD) code, ARL-NSRG3, which includes high-temperature thermodynamics, variable specific heats and transport properties, and finite-rate chemical kinetics. This paper is the most recent in a series of papers that describes efforts to utilize modern CFD, combined with high-performance computers, to reveal gas dynamics and combustion patterns as well as predict chamber pressure and thrust levels in the ISVE including the effects of staged injection.

The Army is developing gelled bipropellants and tactical missile propulsion systems that utilize these propellants for both current and future combat systems. The use of hypergolic gel propellants introduces new challenges in combustion control. One of these challenges is the mixing of oxidizer and fuel to obtain maximum performance from the combustor without increasing the size of the engine. The Army’s impinging stream vortex engine, ISVE, offers an alternative to increasing the volume of the combustion chamber and has already generated excellent performance test data. Since the ISVE is a new concept, analytical models that relate engine performance to engine design parameters are just beginning to emerge. In order to fully exploit the performance advantages that have been realized for the ISVE, it is desirable to understand the underlying flow physics of the engine. This paper describes the Army’s effort to use multidimensional, multiphase computational fluid dynamics, combined with highperformance computers to generate simulations of the ISVE that reveal gas/droplet dynamics and combustion patterns as well as predict chamber pressure and thrust levels for the engine. The goal is to utilize this computational tool to optimize the ISVE performance for a host of strategic Army missions.

NASA Marshall Space Flight Center (MSFC) and the U. S. Army are jointly investigating vortex chamber concepts for cryogenic oxygen/hydrocarbon fuel rocket engine applications. One concept, the Impinging Stream Vortex Chamber Concept (ISVC), has been tested with gel propellants at AMCOM at Redstone Arsenal, Alabama. A version of this concept for the liquid oxygen (LOX)/hydrocarbon fuel (RP-1) propellant system is derived from the one for the gel propellant. An unlike impinging injector is employed to deliver the propellants to the chamber. MSFC has also designed two alternative injection schemes, called the chasing injectors, associated with this vortex chamber concept. In these injection techniques, both propellant jets and their impingement point are in the same chamber cross-sectional plane. One injector has a similar orifice size with the original unlike impinging injector. The second chasing injector has small injection orifices. The team has achieved their objectives of demonstrating the self-cooled chamber wall benefits of ISVC and of providing the test data for validating computational fluids dynamics (CFD) models. These models, in turn, will be used to design the optimum vortex chambers in the future.

In a previous paper, we described a successful technique, the broadband algorithm, for phasing the primary mirror segments of the Keck telescopes to an accuracy of 30 nm. Here we describe a complementary narrow-band algorithm. Although it has a limited dynamic range, it is much faster than the broadband algorithm and can achieve an unprecedented phasing accuracy of approximately 6 nm. Cross checks between these two independent techniques validate both methods to a high degree of confidence. Both algorithms converge to the edge-minimizing configuration of the segmented primary mirror, which is not the same as the overall wave-front-error-minimizing configuration, but we demonstrate that this distinction disappears as the segment aberrations are reduced to zero.