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Analytical determination of control system pulley-axis angles

Description: From Introduction: "The ideas developed in this paper are presented as a means of saving the designer's time and as a method of reduction of control-system friction by an accurate calculation of pulley-axis angles without the errors and difficult checking incident to any graphical method."
Date: September 1941
Creator: Driggs, H I
Partner: UNT Libraries Government Documents Department

Performance of Powerline-Controlled Luminaire Final Report

Description: In previous work, LBNL with Vistron Corp, developed an innovative lighting control system using a communications technology called Phase Cut Carrier (PCC). This report describes the performance of the desktop demonstration system that was developed to test this new controls concept. More detailed information on this project is given in [1]. This report is in fulfillment of deliverable No.1 'Report on Performance of Powerline-carrier Controlled Luminaire' from the FY2004 DOE Work Plan.
Date: December 1, 2004
Creator: Rubinstein, Francis; Pettler, Pete; Snook, Joel; Engelking, Erik & Kiliccote, Sila
Partner: UNT Libraries Government Documents Department

Empirical Estimates of 0Day Vulnerabilities in Control Systems

Description: We define a 0Day vulnerability to be any vulnerability, in deployed software, which has been discovered by at least one person but has not yet been publicly announced or patched. These 0Day vulnerabilities are of particular interest when assessing the risk to well managed control systems which have already effectively mitigated the publicly known vulnerabilities. In these well managed systems the risk contribution from 0Days will have proportionally increased. To aid understanding of how great a risk 0Days may pose to control systems, an estimate of how many are in existence is needed. Consequently, using the 0Day definition given above, we developed and applied a method for estimating how many 0Day vulnerabilities are in existence on any given day. The estimate is made by: empirically characterizing the distribution of the lifespans, measured in days, of 0Day vulnerabilities; determining the number of vulnerabilities publicly announced each day; and applying a novel method for estimating the number of 0Day vulnerabilities in existence on any given day using the number of vulnerabilities publicly announced each day and the previously derived distribution of 0Day lifespans. The method was first applied to a general set of software applications by analyzing the 0Day lifespans of 491 software vulnerabilities and using the daily rate of vulnerability announcements in the National Vulnerability Database. This led to a conservative estimate that in the worst year there were, on average, 2500 0Day software related vulnerabilities in existence on any given day. Using a smaller but intriguing set of 15 0Day software vulnerability lifespans representing the actual time from discovery to public disclosure, we then made a more aggressive estimate. In this case, we estimated that in the worst year there were, on average, 4500 0Day software vulnerabilities in existence on any given day. We then proceeded to identify the subset ...
Date: January 1, 2009
Creator: McQueen, Miles A.; Boyer, Wayne F.; McBride, Sean M. & McQueen, Trevor A.
Partner: UNT Libraries Government Documents Department

Deception used for Cyber Defense of Control Systems

Description: Control system cyber security defense mechanisms may employ deception to make it more difficult for attackers to plan and execute successful attacks. These deceptive defense mechanisms are organized and initially explored according to a specific deception taxonomy and the seven abstract dimensions of security previously proposed as a framework for the cyber security of control systems.
Date: May 1, 2009
Creator: Boyer, Wayne F. & McQueen, Miles A.
Partner: UNT Libraries Government Documents Department

PC/104 Embedded IOCs at Jefferson Lab

Description: Jefferson Lab has developed embedded IOCs based on PC/104 single board computers (SBC) for low level control systems. The PC/104 IOCs run EPICS on top of the RTEMS operating system. Two types of control system configurations are used in different applications, PC/104 SBC with commercial PC/104 I/O cards and PC/104 SBC with custom designed FPGA-based boards. RTEMS was built with CEXP shell to run on the PC/104 SBC. CEXP shell provides the function of dynamic object loading, which is similar to the widely used VxWorks operating system. Standard software configurations were setup for PC/104 IOC application development to provide a familiar format for new projects as well as ease the conversion of applications from VME based IOCs to PC/104 IOCs. Many new projects at Jefferson Lab are going to employ PC/104 SBCs as IOCs and some applications have already been running them for accelerator operations. The PC/104 - RTEMS IOC provides a free open source Real-Time Operating System (RTOS), low cost/maintenance, easily installed/ configured, flexible, and reliable solution for accelerator control and 12GeV Upgrade projects.
Date: October 1, 2009
Creator: Jianxun Yan, Trent Allison, Sue Witherspoon, Anthony Cuffe
Partner: UNT Libraries Government Documents Department

Design and Implementation of an Open, Interoperable AutomatedDemand Response Infrastructure

Description: This paper describes the concept for and lessons from the development and field-testing of an open, interoperable communications infrastructure to support automating demand response (DR). Automating DR allows greater levels of participation and improved reliability and repeatability of the demand response and customer facilities. Automated DR systems have been deployed for critical peak pricing and demand bidding and are being designed for real time pricing. The system is designed to generate, manage, and track DR signals between utilities and Independent System Operators (ISOs) to aggregators and end-use customers and their control systems.
Date: October 1, 2007
Creator: Piette, Mary Ann; Kiliccote, Sila & Ghatikar, Girish
Partner: UNT Libraries Government Documents Department

W-026 acceptance test report plant control system hardware (submittal {number_sign} 220.C)

Description: Acceptance Testing of the WRAP1 Plant Control System Hardware was conducted throughout the construction of WRAPI with the final testing on the Process Area hardware being completed in November 1996. The hardware tests were broken out by the following functional areas; Local Control Units, Operator Control Stations in the WRAP Control Room, DMS Server, PCS Server, Operator Interface Units, printers, DMS terminals, WRAP Local Area Network/Communications, and bar code equipment. This document contains a completed copy of each of the hardware tests along with the applicable test logs and completed test exception reports.
Date: February 14, 1997
Creator: Watson, T.L., Fluor Daniel Hanford
Partner: UNT Libraries Government Documents Department

Device control at CEBAF

Description: CEBAF has undergone a major conversion of its accelerator control system from TACL to EPICS, affecting device control for the RF system, magnets, the machine protection system, the vacuum and valves, and the diagnostic systems including beam position monitors, harps, and the camera and solenoid devices (beam viewers, faraday cups, optical transition radiation viewers, synchrotron radiation monitor, etc.). Altogether these devices require approximately 125,000 EPICS database records. The majority of these devices are controlled through CAMAC; some use embedded microprocessors (RF and magnets), and newer interfaces are in VME. The standard EPICS toolkit was extended to include a driver for CAMAC which supports dual processors on one serial highway, custom database records for magnets and BPMs, and custom data acquisition tasks for the BPMs. 2 refs., 1 tab.
Date: August 1, 1996
Creator: Schaffner, S.; Barker, D. & Bookwalter, V.
Partner: UNT Libraries Government Documents Department

A theoretical investigation of longitudinal stability of airplanes with free controls including effect of friction in control system

Description: From Summary: "The relation between the elevator hinge-moment parameters and the control forces for changes in forward speed and in maneuvers is shown for several values of static stability and elevator mass balance." Factors affecting stability positively and negatively are presented and potential modifications to the elevator control system are provided. The amount of solid friction present was found to be one of the greatest predictors of instability.
Date: February 1944
Creator: Greenberg, Harry & Sternfield, Leonard
Partner: UNT Libraries Government Documents Department

A flight investigation of the handling characteristics of a fighter airplane controlled through a rate type of automatic control system

Description: Report presenting an investigation of the handling qualities of a fighter airplane that is controlled by a pilot supplying signals to a rate type of automatic control system. The handling qualities were investigated in pull-ups, aileron rolls, aerobatics, rough-air flying, and precision tasks.
Date: September 14, 1956
Creator: Russell, Walter R.; Sjoberg, S. A. & Alford, William L.
Partner: UNT Libraries Government Documents Department

Next generation epics interface to abstract data.

Description: The set of externally visible properties associated with process variables in the Experimental Physics and Industrial Control System (EPICS) is predefined in the EPICS base distribution and is therefore not extensible by plug-compatible applications. We believe that this approach, while practical for early versions of the system with a smaller user base, is now severely limiting expansion of the high-level application tool set for EPICS. To eliminate existing barriers, we propose a new C++ based interface to abstract containerized data. This paper describes the new interface, its application to message passing in distributed systems, its application to direct communication between tightly coupled programs co-resident in an address space, and its paramount position in an emerging role for EPICS -- the integration of dissimilar systems.
Date: January 1, 2001
Creator: Hill, J. O. (Jeffrey O.) & Lange, R. (Ralph)
Partner: UNT Libraries Government Documents Department

Using a commercial mathematics software package for on-line analysis at the BNL Accelerator Test Facility

Date: June 14, 1999
Creator: Malone, R. & Wang, X.J.
Partner: UNT Libraries Government Documents Department

Process Control Systems in the Chemical Industry: Safety vs. Security

Description: Traditionally, the primary focus of the chemical industry has been safety and productivity. However, recent threats to our nation’s critical infrastructure have prompted a tightening of security measures across many different industry sectors. Reducing vulnerabilities of control systems against physical and cyber attack is necessary to ensure the safety, security and effective functioning of these systems. The U.S. Department of Homeland Security has developed a strategy to secure these vulnerabilities. Crucial to this strategy is the Control Systems Security and Test Center (CSSTC) established to test and analyze control systems equipment. In addition, the CSSTC promotes a proactive, collaborative approach to increase industry's awareness of standards, products and processes that can enhance the security of control systems. This paper outlines measures that can be taken to enhance the cybersecurity of process control systems in the chemical sector.
Date: April 1, 2005
Creator: Hahn, Jeffrey & Anderson, Thomas
Partner: UNT Libraries Government Documents Department


Description: The results from ten cyber security vulnerability assessments of process control, SCADA and energy management systems, or components of those systems were reviewed to identify common problem areas. The common vulnerabilities ranged from conventional IT security issues to specific weaknesses in control system protocols. In each vulnerability category, relative measures were assigned to the severity of the vulnerability and ease with which an attacker could exploit the vulnerability. Suggested mitigations are identified in each category. Recommended mitigations having the highest impact on reducing vulnerability are listed for asset owners and system vendors.
Date: October 1, 2006
Creator: Fink, Ray
Partner: UNT Libraries Government Documents Department

Recommended Practice: Creating Cyber Forensics Plans for Control Systems

Description: Cyber forensics has been in the popular mainstream for some time, and has matured into an information-technology capability that is very common among modern information security programs. The goal of cyber forensics is to support the elements of troubleshooting, monitoring, recovery, and the protection of sensitive data. Moreover, in the event of a crime being committed, cyber forensics is also the approach to collecting, analyzing, and archiving data as evidence in a court of law. Although scalable to many information technology domains, especially modern corporate architectures, cyber forensics can be challenging when being applied to non-traditional environments, which are not comprised of current information technologies or are designed with technologies that do not provide adequate data storage or audit capabilities. In addition, further complexity is introduced if the environments are designed using proprietary solutions and protocols, thus limiting the ease of which modern forensic methods can be utilized. The legacy nature and somewhat diverse or disparate component aspects of control systems environments can often prohibit the smooth translation of modern forensics analysis into the control systems domain. Compounded by a wide variety of proprietary technologies and protocols, as well as critical system technologies with no capability to store significant amounts of event information, the task of creating a ubiquitous and unified strategy for technical cyber forensics on a control systems device or computing resource is far from trivial. To date, no direction regarding cyber forensics as it relates to control systems has been produced other than what might be privately available from commercial vendors. Current materials have been designed to support event recreation (event-based), and although important, these requirements do not always satisfy the needs associated with incident response or forensics that are driven by cyber incidents. To address these issues and to accommodate for the diversity in both system ...
Date: August 1, 2008
Creator: Cornelius, Eric & Fabro, Mark
Partner: UNT Libraries Government Documents Department

'Known Secure Sensor Measurements' for Critical Infrastructure Systems: Detecting Falsification of System State

Description: This paper describes a first investigation on a low cost and low false alarm, reliable mechanism for detecting manipulation of critical physical processes and falsification of system state. We call this novel mechanism Known Secure Sensor Measurements (KSSM). The method moves beyond analysis of network traffic and host based state information, in fact it uses physical measurements of the process being controlled to detect falsification of state. KSSM is intended to be incorporated into the design of new, resilient, cost effective critical infrastructure control systems. It can also be included in incremental upgrades of already in- stalled systems for enhanced resilience. KSSM is based on known secure physical measurements for assessing the likelihood of an attack and will demonstrate a practical approach to creating, transmitting, and using the known secure measurements for detection.
Date: September 1, 2011
Creator: McQueen, Miles & Giani, Annarita
Partner: UNT Libraries Government Documents Department

Control of a high beta maneuvering reentry vehicle using dynamic inversion.

Description: The design of flight control systems for high performance maneuvering reentry vehicles presents a significant challenge to the control systems designer. These vehicles typically have a much higher ballistic coefficient than crewed vehicles like as the Space Shuttle or proposed crew return vehicles such as the X-38. Moreover, the missions of high performance vehicles usually require a steeper reentry flight path angle, followed by a pull-out into level flight. These vehicles then must transit the entire atmosphere and robustly perform the maneuvers required for the mission. The vehicles must also be flown with small static margins in order to perform the required maneuvers, which can result in highly nonlinear aerodynamic characteristics that frequently transition from being aerodynamically stable to unstable as angle of attack increases. The control system design technique of dynamic inversion has been applied successfully to both high performance aircraft and low beta reentry vehicles. The objective of this study was to explore the application of this technique to high performance maneuvering reentry vehicles, including the basic derivation of the dynamic inversion technique, followed by the extension of that technique to the use of tabular trim aerodynamic models in the controller. The dynamic inversion equations are developed for high performance vehicles and augmented to allow the selection of a desired response for the control system. A six degree of freedom simulation is used to evaluate the performance of the dynamic inversion approach, and results for both nominal and off nominal aerodynamic characteristics are presented.
Date: May 1, 2005
Creator: Watts, Alfred Chapman
Partner: UNT Libraries Government Documents Department

A Decade of NSTX Operations Using Collaborative Software

Description: Since the beginning of the National Spherical Torus Experiment's (NSTX) research activities in 1999, open-source and collaborative software have been used extensively for experimental operations. The software included Experimental Physics and Industrial Control System (EPICS) and the Model Data System plus (MDSplus). This paper will begin with a retrospective of ten years of integrated computing, control, and data analysis on NSTX. A variety of practical issues will be reviewed such as: system reliability, availability, and maintainability; using open source software with commercialoff- the-shelf (COTS) hardware; obsolescence and remaining current. Recent improvements, current status, and emerging issues will be presented. Numerous proposals for NSTX upgrades have been made that will extend the performance and operating lifetime of NSTX. In light of this, a collective strategy for improving NSTX's collaborative software model for a new decade of operations will be examined.
Date: September 24, 2009
Creator: P. Sichta, W. Davis, J. Dong, D. Mastrovito, G. Tchilinguirian, G. Zimmer
Partner: UNT Libraries Government Documents Department

On-line reactor surveillance algorithm based on multivariate analysis of noise

Description: A mini-computer based surveillance algorithm for monitoring signals from nuclear power plants to provide advanced warning of anomalous conditions has been developed and implemented for on-line applications. The reactor state is characterized by the analysis of noise signals. During an observation period when normal conditions prevail, the surveillance algorithm utilizes these noise characterizations to form a statistical description of normal reactor behavior. At the conclusion of this observation period, the surveillance algorithm examines each new incoming characterization to determine if it differs signicantly from the normal description. (auth)
Date: January 1, 1975
Creator: Piety, K.R. & Robinson, J.C.
Partner: UNT Libraries Government Documents Department