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Some approaches for modeling and analysis of a parallel mechanism with stewart platform architecture

Description: Parallel mechanisms represent a family of devices based on a closed kinematic architecture. This is in contrast to serial mechanisms, which are comprised of a chain-like series of joints and links in an open kinematic architecture. The closed architecture of parallel mechanisms offers certain benefits and disadvantages.
Date: May 1, 1998
Creator: Sapio, V. De
Partner: UNT Libraries Government Documents Department

Scaling Laws for Mesoscale and Microscale Systems

Description: The set of laws developed and presented here is by no means exhaustive. Techniques have been present to aid in the development of additional scaling laws and to combine these and other laws to produce additional useful relationships. Some of the relationships produced here have yielded perhaps surprising results. Examples include the fifth order scaling law for electromagnetic motor torque and the zero order scaling law for capacitive motor power. These laws demonstrate important facts about actuators in small-scale systems. The primary intent of this introduction into scaling law analysis is to provide needed tools to examine possible areas of the research in small-scale systems and direct research toward more fruitful areas. Numerous examples have been included to show the validity of developing scaling laws based on first principles and how real world systems tend to obey these laws even when many other variables may potentially come into play. Development of further laws may well serve to provide important high-level direction to the continued development of small-scale systems.
Date: August 23, 1999
Creator: Spletzer, Barry
Partner: UNT Libraries Government Documents Department

Deriving Properties of Systems from Properties of Parts and Lists of Connections

Description: This paper presents an algorithm in PROLOG for compiling recursively computable descriptions of system behavior from computable descriptions of behavior for parts and lists of interconnections. We give a set of conditions that must be satisfied by various data structures in the computation. It seems possible to provide an informal verification (by hand) that these conditions are true also of the output.
Date: December 1986
Creator: Gabriel, John R. & Chapman, Richard O.
Partner: UNT Libraries Government Documents Department

Assessment of packaging needs for the National Nuclear Security Administration's Office of Defense Programs.

Description: This report documents a study by Sandia's Systems Analysis Group to assess the status of, and need for, shipping containers to support the mission of National Nuclear Security Administration's Office of Defense Program. The focus of the study evolved into determining the status of existing packages relative to Federal Regulations for the Department of Transportation and Nuclear Regulatory Commission. Proposed regulatory changes will mandate the elimination or restricted use of many current DP packages. This study clarifies numerous misconceptions regarding these regulatory changes and status of packages relative to them. We have proposed guidelines for new package development based on the regulatory status of existing packages. Additionally, we have identified attributes that will make new packagings more amenable to accommodating new contents. This will allow the new packagings to better fill voids in container needs that are recognized but unable to be characterized at this time.
Date: November 1, 2003
Creator: Zeuch, David Henry & Watson, Robert A.
Partner: UNT Libraries Government Documents Department

Hydra: a service oriented architecture for scientific simulation integration

Description: One of the current major challenges in scientific modeling and simulation, in particular in the infrastructure-analysis community, is the development of techniques for efficiently and automatically coupling disparate tools that exist in separate locations on different platforms, implemented in a variety of languages and designed to be standalone. Recent advances in web-based platforms for integrating systems such as SOA provide an opportunity to address these challenges in a systematic fashion. This paper describes Hydra, an integrating architecture for infrastructure modeling and simulation that defines geography-based schemas that, when used to wrap existing tools as web services, allow for seamless plug-and-play composability. Existing users of these tools can enhance the value of their analysis by assessing how the simulations of one tool impact the behavior of another tool and can automate existing ad hoc processes and work flows for integrating tools together.
Date: January 1, 2008
Creator: Bent, Russell; Djidjev, Tatiana; Hayes, Birch P; Holland, Joe V; Khalsa, Hari S; Linger, Steve P et al.
Partner: UNT Libraries Government Documents Department

Systems Analysis Programs for Hands-on Integrated Reliability Evaluations (SAPHIRE) Code Reference Manual

Description: The Systems Analysis Programs for Hands-on Integrated Reliability Evaluations (SAPHIRE) is a software application developed for performing a complete probabilistic risk assessment (PRA) using a personal computer. SAPHIRE is funded by the U.S. Nuclear Regulatory Commission (NRC) and developed by the Idaho National Laboratory (INL). The INL's primary role in this project is that of software developer. However, the INL also plays an important role in technology transfer by interfacing and supporting SAPHIRE users comprised of a wide range of PRA practitioners from the NRC, national laboratories, the private sector, and foreign countries. SAPHIRE can be used to model a complex system’s response to initiating events, quantify associated damage outcome frequencies, and identify important contributors to this damage (Level 1 PRA) and to analyze containment performance during a severe accident and quantify radioactive releases (Level 2 PRA). It can be used for a PRA evaluating a variety of operating conditions, for example, for a nuclear reactor at full power, low power, or at shutdown conditions. Furthermore, SAPHIRE can be used to analyze both internal and external initiating events and has special features for transforming models built for internal event analysis to models for external event analysis. It can also be used in a limited manner to quantify risk in terms of release consequences to both the public and the environment (Level 3 PRA). SAPHIRE includes a separate module called the Graphical Evaluation Module (GEM). GEM provides a highly specialized user interface with SAPHIRE that automates SAPHIRE process steps for evaluating operational events at commercial nuclear power plants. Using GEM, an analyst can estimate the risk associated with operational events in a very efficient and expeditious manner. This reference guide will introduce the SAPHIRE Version 7.0 software. A brief discussion of the purpose and history of the software is included along ...
Date: August 1, 2008
Creator: Smith, C. L.; Kvarfordt, K. J. & Wood, S. T.
Partner: UNT Libraries Government Documents Department

Physics Basis and Simulation of Burning Plasma Physics for the Fusion Ignition Research Experiment (FIRE)

Description: The FIRE [Fusion Ignition Research Experiment] design for a burning plasma experiment is described in terms of its physics basis and engineering features. Systems analysis indicates that the device has a wide operating space to accomplish its mission, both for the ELMing H-mode reference and the high bootstrap current/high beta advanced tokamak regimes. Simulations with 1.5D transport codes reported here both confirm and constrain the systems projections. Experimental and theoretical results are used to establish the basis for successful burning plasma experiments in FIRE.
Date: January 18, 2002
Creator: Kessel, C.E.; Meade, D. & Jardin, S.C.
Partner: UNT Libraries Government Documents Department

Operations other than war: Requirements for analysis tools research report

Description: This report documents the research effort to determine the requirements for new or improved analysis tools to support decisions at the strategic and operational levels for military Operations Other than War (OOTW). The work was performed for the Commander in Chief, U.S. Pacific Command (USCINCPAC). The data collection was based on workshops attended by experts in OOTWs: analysis personnel from each of the Combatant Commands, the Services, the Office of the Secretary of Defense (OSD), the Joint Staff, and other knowledgeable personnel. Further data were gathered from other workshops and conferences and from the literature. The results of this research begin with the creation of a taxonomy of OOTWs: categories of operations, attributes of operations, and tasks requiring analytical support. The tasks are connected to the Joint Staff`s Universal Joint Task List (UJTL). Historical OOTWs are analyzed to produce frequency distributions by category and responsible CINC. The analysis products are synthesized into a list of requirements for analytical tools and definitions of the requirements. The report concludes with a timeline or roadmap for satisfying the requirements.
Date: December 1, 1996
Creator: Hartley, D.S. III
Partner: UNT Libraries Government Documents Department

Waste analysis plan for T Plant Complex

Description: Washington Administration Code 173-303-300 requires that a waste analysis plan (WAP) be provided by a treatment, storage, and/or disposal (TSD) unit to confirm their knowledge about a dangerous and/or mixed waste to ensure that the waste is managed properly. The specific objectives of the WAP are as follows: Ensure safe management of waste during treatment and storage; Ensure that waste generated during operational activities is properly designated in accordance with regulatory requirements; Provide chemical and physical analysis of representative samples of the waste stored for characterization and/or verification before the waste is transferred to another TSD unit; Ensure compliance with land disposal restriction (LDR) requirements for treated waste; and Provide basis for work plans that describes waste analysis for development of new treatment technologies.
Date: April 12, 1996
Creator: Williams, J.F.
Partner: UNT Libraries Government Documents Department

A steerable/distance enhanced penetrometer delivery system: Phase II. Topical report

Description: This report summarizes the phase II work on the Position Location Device (POLO) for penetrometers. Phase II was carried out to generate an integrated design of a full-scale steerable/distance enhanced penetrometer delivery system. Steering provides for the controlled and directional use of the penetrometer, while vibratory thrusting can provide greater penetration ability.
Date: May 1, 1996
Creator: Amini, A.; Shenhar, J. & Lum, K.D.
Partner: UNT Libraries Government Documents Department

A thematic approach to system safety

Description: Sandia National Laboratories has refined a process for developing inherently safer system designs, based on methods used by the Laboratories to design detonation safety into nuclear weapons. The process was created when the Laboratories realized that standard engineering practices did not provide the level of safety assurance necessary for nuclear weapon operations, with their potential for catastrophic accidents. A systematic approach, which relies on mutually supportive design principles integrated through fundamental physical principles, was developed to ensure a predictably safe system response under a variety of operational and accident based stresses. Robust, safe system designs result from this thematic approach to safety, minimizing the number of safety critical features. This safety assurance process has two profound benefits: the process avoids the need to understand or limit the ultimate intensity of off normal environments and it avoids the requirement to analyze and test a bewildering and virtually infinite array of accident environment scenarios (e.g., directional threats, sequencing of environments, time races, etc.) to demonstrate conformance to all safety requirements.
Date: December 1, 1997
Creator: Ekman, M.E.; Werner, P.W.; Covan, J.M. & D`Antonio, P.E.
Partner: UNT Libraries Government Documents Department

Waste management project technical baseline description

Description: A systems engineering approach has been taken to describe the technical baseline under which the Waste Management Project is currently operating. The document contains a mission analysis, function analysis, requirement analysis, interface definitions, alternative analysis, system definition, documentation requirements, implementation definitions, and discussion of uncertainties facing the Project.
Date: August 13, 1997
Creator: Sederburg, J.P.
Partner: UNT Libraries Government Documents Department

Failure modes in surface micromachined microelectromechanical actuators

Description: In order for the rapidly emerging field of MicroElectroMechanical Systems (MEMS) to meet its extraordinary expectations regarding commercial impact, issues pertaining to how they fail must be understood. The authors identify failure modes common to a broad range of MEMS actuators, including adhesion (stiction) and friction induced failures caused by improper operational methods, mechanical instabilities, and electrical instabilities. Demonstrated methods to mitigate these failure modes include implementing optimized designs, model based operational methods, and chemical surface treatments.
Date: March 1, 1998
Creator: Miller, S.L.; Rodgers, M.S.; LaVigne, G.; Sniegowski, J.J.; Clews, P.; Tanner, D.M. et al.
Partner: UNT Libraries Government Documents Department

Characterizing reliability in a product/process design-assurance program

Description: Over the years many advancing techniques in the area of reliability engineering have surfaced in the military sphere of influence, and one of these techniques is Reliability Growth Testing (RGT). Private industry has reviewed RGT as part of the solution to their reliability concerns, but many practical considerations have slowed its implementation. It`s objective is to demonstrate the reliability requirement of a new product with a specified confidence. This paper speaks directly to that objective but discusses a somewhat different approach to achieving it. Rather than conducting testing as a continuum and developing statistical confidence bands around the results, this Bayesian updating approach starts with a reliability estimate characterized by large uncertainty and then proceeds to reduce the uncertainty by folding in fresh information in a Bayesian framework.
Date: October 1, 1997
Creator: Kerscher, W.J. III; Booker, J.M.; Bement, T.R. & Meyer, M.A.
Partner: UNT Libraries Government Documents Department