Programmable Logic Controllers. Teacher Edition.
ERIC Educational Resources Information Center
Rauh, Bob; Kaltwasser, Stan
These materials were developed for a seven-unit secondary or postsecondary education course on programmable logic controllers (PLCs) that treats most of the skills needed to work effectively with PLCs as programming skills. The seven units of the course cover the following topics: fundamentals of programmable logic controllers; contracts, timers,…
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mulder, John C.; Schwartz, Moses Daniel; Berg, Michael J.
2013-10-01
Critical infrastructures, such as electrical power plants and oil refineries, rely on programmable logic controllers (PLCs) to control essential processes. State of the art security cannot detect attacks on PLCs at the hardware or firmware level. This renders critical infrastructure control systems vulnerable to costly and dangerous attacks. WeaselBoard is a PLC backplane analysis system that connects directly to the PLC backplane to capture backplane communications between modules. WeaselBoard forwards inter-module traffic to an external analysis system that detects changes to process control settings, sensor values, module configuration information, firmware updates, and process control program (logic) updates. WeaselBoard provides zero-daymore » exploit detection for PLCs by detecting changes in the PLC and the process. This approach to PLC monitoring is protected under U.S. Patent Application 13/947,887.« less
Detecting Payload Attacks on Programmable Logic Controllers (PLCs)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Yang, Huan
Programmable logic controllers (PLCs) play critical roles in industrial control systems (ICS). Providing hardware peripherals and firmware support for control programs (i.e., a PLC’s “payload”) written in languages such as ladder logic, PLCs directly receive sensor readings and control ICS physical processes. An attacker with access to PLC development software (e.g., by compromising an engineering workstation) can modify the payload program and cause severe physical damages to the ICS. To protect critical ICS infrastructure, we propose to model runtime behaviors of legitimate PLC payload program and use runtime behavior monitoring in PLC firmware to detect payload attacks. By monitoring themore » I/O access patterns, network access patterns, as well as payload program timing characteristics, our proposed firmware-level detection mechanism can detect abnormal runtime behaviors of malicious PLC payload. Using our proof-of-concept implementation, we evaluate the memory and execution time overhead of implementing our proposed method and find that it is feasible to incorporate our method into existing PLC firmware. In addition, our evaluation results show that a wide variety of payload attacks can be effectively detected by our proposed approach. The proposed firmware-level payload attack detection scheme complements existing bumpin- the-wire solutions (e.g., external temporal-logic-based model checkers) in that it can detect payload attacks that violate realtime requirements of ICS operations and does not require any additional apparatus.« less
Programmable logic controller optical fibre sensor interface module
NASA Astrophysics Data System (ADS)
Allwood, Gary; Wild, Graham; Hinckley, Steven
2011-12-01
Most automated industrial processes use Distributed Control Systems (DCSs) or Programmable Logic Controllers (PLCs) for automated control. PLCs tend to be more common as they have much of the functionality of DCSs, although they are generally cheaper to install and maintain. PLCs in conjunction with a human machine interface form the basis of Supervisory Control And Data Acquisition (SCADA) systems, combined with communication infrastructure and Remote Terminal Units (RTUs). RTU's basically convert different sensor measurands in to digital data that is sent back to the PLC or supervisory system. Optical fibre sensors are becoming more common in industrial processes because of their many advantageous properties. Being small, lightweight, highly sensitive, and immune to electromagnetic interference, means they are an ideal solution for a variety of diverse sensing applications. Here, we have developed a PLC Optical Fibre Sensor Interface Module (OFSIM), in which an optical fibre is connected directly to the OFSIM located next to the PLC. The embedded fibre Bragg grating sensors, are highly sensitive and can detect a number of different measurands such as temperature, pressure and strain without the need for a power supply.
Fuzz Testing of Industrial Network Protocols in Programmable Logic Controllers
2017-12-01
PLCs) are vital components in these cyber-physical systems. The industrial network protocols used to communicate between nodes in a control network...AB/RA) MicroLogix 1100 PLC through its implementation of EtherNet/IP, Common Industrial Protocol (CIP), and Programmable Controller Communication ...Commands (PCCC) communication protocols. This research also examines whether cross-generational vulnerabilities exist in the more advanced AB/RA
Implementation of RS-485 Communication between PLC and PC of Distributed Control System Based on VB
NASA Astrophysics Data System (ADS)
Lian Zhang, Chuan; Da Huang, Zhi; Qing Zhou, Gui; Chong, Kil To
2015-05-01
This paper focuses on achieving RS-485 communication between programmable logical controller (PLC) and PC based on visual basic 6.0 (VB6.0) on an experimental automatic production line. Mitsubishi FX2N PLCs and a PC are chosen as slave stations and main station, respectively. Monitoring software is developed using VB6.0 for data input/output, flow control and online parameters setting. As a result, all functions are fulfilled with robust performance. It is concluded from results that one PC can monitor several PLCs using RS-485 communication.
Bidirectional automatic release of reserve for low voltage network made with low capacity PLCs
NASA Astrophysics Data System (ADS)
Popa, I.; Popa, G. N.; Diniş, C. M.; Deaconu, S. I.
2018-01-01
The article presents the design of a bidirectional automatic release of reserve made on two types low capacity programmable logic controllers: PS-3 from Klöckner-Moeller and Zelio from Schneider. It analyses the electronic timing circuits that can be used for making the bidirectional automatic release of reserve: time-on delay circuit and time-off delay circuit (two types). In the paper are present the sequences code for timing performed on the PS-3 PLC, the logical functions for the bidirectional automatic release of reserve, the classical control electrical diagram (with contacts, relays, and time relays), the electronic control diagram (with logical gates and timing circuits), the code (in IL language) made for the PS-3 PLC, and the code (in FBD language) made for Zelio PLC. A comparative analysis will be carried out on the use of the two types of PLC and will be present the advantages of using PLCs.
D0 General Support: The Use of Programmable Logic Controllers (PLCS) at D0
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hance, R.; /Fermilab
With the exception of control of heating, ventilation, and air conditioning (HVAC) ventilation fans, and their shutdown in the case of smoke in the ducts, all implementations of Programmable Logic Controllers (PLCs) in Dzero have been made within the fundamental premise that no uncertified PLC apparatus shall be entrusted with the safety of equipment or personnel. Thus although PLCs are used to control and monitor all manner of intricate equipment, simple hardware interlocks and relief devices provide basic protection against component failure, control failure, or inappropriate control operation. Nevertheless, this report includes two observations as follows: (1) It may bemore » prudent to reconfigure the link between the Pyrotronics system and the HVAC system such that the Pyrotronics system provides interlocks to the ventilation fans instead of control inputs to the uncertified HVAC PLCs. Although the Pyrotronics system is certified and maintained to life safety standards, the HVAC system is not. A hardware or software failure of the HVAC system probably should not be allowed to result in the situation where the ventilation fans in a smoke filled duct continue to operate. Dan Markley is investigating this matter. (2) It may also be prudent to examine the network security of those systems connected to the Fermilab WAN (HVAC, Cryo, and Solenoid Controls). Even though the impact of a successful hack might only be to operations, it might nevertheless be disruptive and could be expensive. The risks should perhaps be analyzed. One of the most attractive features of these systems, from a user's viewpoint, is their unlimited networking. The unlimited networking that makes the systems so convenient to legitimate access also makes them vulnerable to illegitimate access.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Yang, Huan; Cheng, Liang; Chuah, Mooi Choo
In the generation, transmission, and distribution sectors of the smart grid, intelligence of field devices is realized by programmable logic controllers (PLCs). Many smart-grid subsystems are essentially cyber-physical energy systems (CPES): For instance, the power system process (i.e., the physical part) within a substation is monitored and controlled by a SCADA network with hosts running miscellaneous applications (i.e., the cyber part). To study the interactions between the cyber and physical components of a CPES, several co-simulation platforms have been proposed. However, the network simulators/emulators of these platforms do not include a detailed traffic model that takes into account the impactsmore » of the execution model of PLCs on traffic characteristics. As a result, network traces generated by co-simulation only reveal the impacts of the physical process on the contents of the traffic generated by SCADA hosts, whereas the distinction between PLCs and computing nodes (e.g., a hardened computer running a process visualization application) has been overlooked. To generate realistic network traces using co-simulation for the design and evaluation of applications relying on accurate traffic profiles, it is necessary to establish a traffic model for PLCs. In this work, we propose a parameterized model for PLCs that can be incorporated into existing co-simulation platforms. We focus on the DNP3 subsystem of slave PLCs, which automates the processing of packets from the DNP3 master. To validate our approach, we extract model parameters from both the configuration and network traces of real PLCs. Simulated network traces are generated and compared against those from PLCs. Our evaluation shows that our proposed model captures the essential traffic characteristics of DNP3 slave PLCs, which can be used to extend existing co-simulation platforms and gain further insights into the behaviors of CPES.« less
DOT National Transportation Integrated Search
2008-12-01
Programmable logic controllers (PLCs) were installed at several key ramps with the assistance of the City of Portland and used to capture additional data about ramp operations that are not otherwise logged. The data include include the activation and...
DOT National Transportation Integrated Search
2008-12-01
Programmable logic controllers (PLCs) were installed at several key ramps with the assistance of the City of Portland and used to capture additional data about ramp operations that are not otherwise logged. The data include the activation and deactiv...
Modeling DNP3 Traffic Characteristics of Field Devices in SCADA Systems of the Smart Grid
DOE Office of Scientific and Technical Information (OSTI.GOV)
Yang, Huan; Cheng, Liang; Chuah, Mooi Choo
In the generation, transmission, and distribution sectors of the smart grid, intelligence of field devices is realized by programmable logic controllers (PLCs). Many smart-grid subsystems are essentially cyber-physical energy systems (CPES): For instance, the power system process (i.e., the physical part) within a substation is monitored and controlled by a SCADA network with hosts running miscellaneous applications (i.e., the cyber part). To study the interactions between the cyber and physical components of a CPES, several co-simulation platforms have been proposed. However, the network simulators/emulators of these platforms do not include a detailed traffic model that takes into account the impactsmore » of the execution model of PLCs on traffic characteristics. As a result, network traces generated by co-simulation only reveal the impacts of the physical process on the contents of the traffic generated by SCADA hosts, whereas the distinction between PLCs and computing nodes (e.g., a hardened computer running a process visualization application) has been overlooked. To generate realistic network traces using co-simulation for the design and evaluation of applications relying on accurate traffic profiles, it is necessary to establish a traffic model for PLCs. In this work, we propose a parameterized model for PLCs that can be incorporated into existing co-simulation platforms. We focus on the DNP3 subsystem of slave PLCs, which automates the processing of packets from the DNP3 master. To validate our approach, we extract model parameters from both the configuration and network traces of real PLCs. Simulated network traces are generated and compared against those from PLCs. Our evaluation shows that our proposed model captures the essential traffic characteristics of DNP3 slave PLCs, which can be used to extend existing co-simulation platforms and gain further insights into the behaviors of CPES.« less
The use of programmable logic controllers (PLC) for rocket engine component testing
NASA Technical Reports Server (NTRS)
Nail, William; Scheuermann, Patrick; Witcher, Kern
1991-01-01
Application of PLCs to the rocket engine component testing at a new Stennis Space Center Component Test Facility is suggested as an alternative to dedicated specialized computers. The PLC systems are characterized by rugged design, intuitive software, fault tolerance, flexibility, multiple end device options, networking capability, and built-in diagnostics. A distributed PLC-based system is projected to be used for testing LH2/LOx turbopumps required for the ALS/NLS rocket engines.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Palomar, J.; Wyman, R.
This document provides recommendations to guide reviewers in the application of Programmable Logic Controllers (PLCS) to the control, monitoring and protection of nuclear reactors. The first topics addressed are system-level design issues, specifically including safety. The document then discusses concerns about the PLC manufacturing organization and the protection system engineering organization. Supplementing this document are two appendices. Appendix A summarizes PLC characteristics. Specifically addressed are those characteristics that make the PLC more suitable for emergency shutdown systems than other electrical/electronic-based systems, as well as characteristics that improve reliability of a system. Also covered are PLC characteristics that may create anmore » unsafe operating environment. Appendix B provides an overview of the use of programmable logic controllers in emergency shutdown systems. The intent is to familiarize the reader with the design, development, test, and maintenance phases of applying a PLC to an ESD system. Each phase is described in detail and information pertinent to the application of a PLC is pointed out.« less
Interfacing the Controllogics PLC over Ethernet/IP.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kasemir, K. U.; Dalesio, L. R.
2001-01-01
The Allen-Bradley ControlLogix [1] line of programmable logic controllers (PLCs) offers several interfaces: Ethernet, ControlNet, DeviceNet, RS-232 and others. The ControlLogix Ethernet interface module 1756-ENET uses EtherNet/IP, the ControlNet protocol [2], encapsulated in Ethernet packages, with specific service codes [3]. A driver for the Experimental Physics and Industrial Control System (EPICS) has been developed that utilizes this EtherNet/IP protocol for controllers running the vxWorks RTOS as well as a Win32 and Unix/Linux test program. Features, performance and limitations of this interface are presented.
Refurbishment and Automation of Thermal Vacuum Facilities at NASA/GSFC
NASA Technical Reports Server (NTRS)
Dunn, Jamie; Gomez, Carlos; Donohue, John; Johnson, Chris; Palmer, John; Sushon, Janet
1999-01-01
The thermal vacuum facilities located at the Goddard Space Flight Center (GSFC) have supported both manned and unmanned space flight since the 1960s. Of the eleven facilities, currently ten of the systems are scheduled for refurbishment or replacement as part of a five-year implementation. Expected return on investment includes the reduction in test schedules, improvements in safety of facility operations, and reduction in the personnel support required for a test. Additionally, GSFC will become a global resource renowned for expertise in thermal engineering, mechanical engineering, and for the automation of thermal vacuum facilities and tests. Automation of the thermal vacuum facilities includes the utilization of Programmable Logic Controllers (PLCs), the use of Supervisory Control and Data Acquisition (SCADA) systems, and the development of a centralized Test Data Management System. These components allow the computer control and automation of mechanical components such as valves and pumps. The project of refurbishment and automation began in 1996 and has resulted in complete computer control of one facility (Facility 281), and the integration of electronically controlled devices and PLCs in multiple others.
Refurbishment and Automation of Thermal Vacuum Facilities at NASA/GSFC
NASA Technical Reports Server (NTRS)
Dunn, Jamie; Gomez, Carlos; Donohue, John; Johnson, Chris; Palmer, John; Sushon, Janet
1998-01-01
The thermal vacuum facilities located at the Goddard Space Flight Center (GSFC) have supported both manned and unmanned space flight since the 1960s. Of the eleven facilities, currently ten of the systems are scheduled for refurbishment or replacement as part of a five-year implementation. Expected return on investment includes the reduction in test schedules, improvements in safety of facility operations, and reduction in the personnel support required for a test. Additionally, GSFC will become a global resource renowned for expertise in thermal engineering, mechanical engineering, and for the automation of thermal vacuum facilities and tests. Automation of the thermal vacuum facilities includes the utilization of Programmable Logic Controllers (PLCs), the use of Supervisory Control and Data Acquisition (SCADA) systems, and the development of a centralized Test Data Management System. These components allow the computer control and automation of mechanical components such as valves and pumps. The project of refurbishment and automation began in 1996 and has resulted in complete computer control of one facility (Facility 281), and the integration of electronically controlled devices and PLCs in multiple others.
Realization of a Complex Control & Diagnosis System on Simplified Hardware
NASA Astrophysics Data System (ADS)
Stetter, R.; Swamy Prasad, M.
2015-11-01
Energy is an important factor in today's industrial environment. Pump systems account for about 20% of the total industrial electrical energy consumption. Several studies show that with proper monitoring, control and maintenance, the efficiency of pump systems can be increased. Controlling pump systems with intelligent systems can help to reduce a pump's energy consumption by up to one third of its original consumption. The research in this paper was carried out in the scope of a research project which involves modelling and simulation of pump systems. This paper focuses on the future implementation of modelling capabilities in PLCs (programmable logic controllers). The whole project aims to use a pump itself as the sensor rather than introducing external sensors into the system, which would increase the cost considerably. One promising approach for an economic and robust industrial implementation of this intelligence is the use of PLCs. PLCs can be simulated in multiple ways; in this project, Codesys was chosen for several reasons which are explained in this paper. The first part of this paper explains the modelling of a pump itself, the process load of the asynchronous motor with a control system, and the simulation possibilities of the motor in Codesys. The second part describes the simulation and testing of a system realized. The third part elaborates the Codesys system structure and interfacing of the system with external files. The final part consists of comparing the result with an earlier Matlab/SIMULINK model and original test data.
Project-Based Learning in Programmable Logic Controller
NASA Astrophysics Data System (ADS)
Seke, F. R.; Sumilat, J. M.; Kembuan, D. R. E.; Kewas, J. C.; Muchtar, H.; Ibrahim, N.
2018-02-01
Project-based learning is a learning method that uses project activities as the core of learning and requires student creativity in completing the project. The aims of this study is to investigate the influence of project-based learning methods on students with a high level of creativity in learning the Programmable Logic Controller (PLC). This study used experimental methods with experimental class and control class consisting of 24 students, with 12 students of high creativity and 12 students of low creativity. The application of project-based learning methods into the PLC courses combined with the level of student creativity enables the students to be directly involved in the work of the PLC project which gives them experience in utilizing PLCs for the benefit of the industry. Therefore, it’s concluded that project-based learning method is one of the superior learning methods to apply on highly creative students to PLC courses. This method can be used as an effort to improve student learning outcomes and student creativity as well as to educate prospective teachers to become reliable educators in theory and practice which will be tasked to create qualified human resources candidates in order to meet future industry needs.
SNE Industrial Fieldbus Interface
NASA Technical Reports Server (NTRS)
Lucena, Angel; Raines, Matthew; Oostdyk, Rebecca; Mata, Carlos
2011-01-01
Programmable logic controllers (PLCs) have very limited diagnostic and no prognostic capabilities, while current smart sensor designs do not have the capability to communicate over Fieldbus networks. The aim is to interface smart sensors with PLCs so that health and status information, such as failure mode identification and measurement tolerance, can be communicated via an industrial Fieldbus such as ControlNet. The SNE Industrial Fieldbus Interface (SIFI) is an embedded device that acts as a communication module in a networked smart sensor. The purpose is to enable a smart sensor to communicate health and status information to other devices, such as PLCs, via an industrial Fieldbus networking protocol. The SNE (Smart Network Element) is attached to a commercial off-the-shelf Any bus-S interface module through the SIFI. Numerous Anybus-S modules are available, each one designed to interface with a specific Fieldbus. Development of the SIFI focused on communications using the ControlNet protocol, but any of the Anybus-S modules can be used. The SIFI communicates with the Any-bus module via a data buffer and mailbox system on the Anybus module, and supplies power to the module. The Anybus module transmits and receives data on the Fieldbus using the proper protocol. The SIFI is intended to be connected to other existing SNE modules in order to monitor the health and status of a transducer. The SIFI can also monitor aspects of its own health using an onboard watchdog timer and voltage monitors. The SIFI also has the hardware to drive a touchscreen LCD (liquid crystal display) unit for manual configuration and status monitoring.
My Rewarding Summer Research Experience at NASA
NASA Technical Reports Server (NTRS)
Aviles, Andres
2007-01-01
My summer research experience at the Kennedy Space Center has been a truly rewarding one. As an electrical engineering student at the University of South Florida, I was blessed with a beneficial opportunity to gain valuable knowledge in my career, and also apply it through working at NASA. One of my inspirations in becoming an engineer is to work at NASA someday, and I was very excited and honored to have this opportunity. My goal in this internship was to strengthen my preparation in becoming an engineer by learning new material, acquiring skills by practicing what I learned, and discovering the expectations of engineering work at NASA. Through this summer research, I was able to learn new computer programs and perform various tasks that gave me experience and skills as an engineer. My primary job was to conduct work on the Constellation Test article, which is a simulation model of the Crew Launch Vehicle (CLV) tanking system. This is a prototype of a launch facility and an Ares I Vehicle, which God willing will transport astronauts to the moon. Construction of the CLV is in progress and a test launch is anticipated for 2010. Moreover, the Test Article serves as a demonstration too, training test bed, and may be expanded for new simulation of launch system elements, which could be applied to real life operations. The test article is operated and run by a Programmable Logic Controller (PLC), which is a digital computer that is used to control all forms of machinery such as those in manufacturing buildings and other industries. PLCs are different than other computers because of the physical protection they have against damaging environmental conditions that would destroy other computers. Also, PLCs are equipped with lots of input and output connections that allow extensive amounts of commands to be executed, which would normally require many computers to do. Therefore, PLCs are small, rugged, and extremely powerful tools that may continue to be employed at NASA. Furthermore, in order to conduct productive work on the Test Article, I needed to learn the computer program called RS Logics 5000.
Model-based approach for cyber-physical attack detection in water distribution systems.
Housh, Mashor; Ohar, Ziv
2018-08-01
Modern Water Distribution Systems (WDSs) are often controlled by Supervisory Control and Data Acquisition (SCADA) systems and Programmable Logic Controllers (PLCs) which manage their operation and maintain a reliable water supply. As such, and with the cyber layer becoming a central component of WDS operations, these systems are at a greater risk of being subjected to cyberattacks. This paper offers a model-based methodology based on a detailed hydraulic understanding of WDSs combined with an anomaly detection algorithm for the identification of complex cyberattacks that cannot be fully identified by hydraulically based rules alone. The results show that the proposed algorithm is capable of achieving the best-known performance when tested on the data published in the BATtle of the Attack Detection ALgorithms (BATADAL) competition (http://www.batadal.net). Copyright © 2018. Published by Elsevier Ltd.
Jeyabalan, Vickneswaran; Samraj, Andrews; Loo, Chu Kiong
2010-10-01
Aiming at the implementation of brain-machine interfaces (BMI) for the aid of disabled people, this paper presents a system design for real-time communication between the BMI and programmable logic controllers (PLCs) to control an electrical actuator that could be used in devices to help the disabled. Motor imaginary signals extracted from the brain’s motor cortex using an electroencephalogram (EEG) were used as a control signal. The EEG signals were pre-processed by means of adaptive recursive band-pass filtrations (ARBF) and classified using simplified fuzzy adaptive resonance theory mapping (ARTMAP) in which the classified signals are then translated into control signals used for machine control via the PLC. A real-time test system was designed using MATLAB for signal processing, KEP-Ware V4 OLE for process control (OPC), a wireless local area network router, an Omron Sysmac CPM1 PLC and a 5 V/0.3A motor. This paper explains the signal processing techniques, the PLC's hardware configuration, OPC configuration and real-time data exchange between MATLAB and PLC using the MATLAB OPC toolbox. The test results indicate that the function of exchanging real-time data can be attained between the BMI and PLC through OPC server and proves that it is an effective and feasible method to be applied to devices such as wheelchairs or electronic equipment.
Creating and Testing Simulation Software
NASA Technical Reports Server (NTRS)
Heinich, Christina M.
2013-01-01
The goal of this project is to learn about the software development process, specifically the process to test and fix components of the software. The paper will cover the techniques of testing code, and the benefits of using one style of testing over another. It will also discuss the overall software design and development lifecycle, and how code testing plays an integral role in it. Coding is notorious for always needing to be debugged due to coding errors or faulty program design. Writing tests either before or during program creation that cover all aspects of the code provide a relatively easy way to locate and fix errors, which will in turn decrease the necessity to fix a program after it is released for common use. The backdrop for this paper is the Spaceport Command and Control System (SCCS) Simulation Computer Software Configuration Item (CSCI), a project whose goal is to simulate a launch using simulated models of the ground systems and the connections between them and the control room. The simulations will be used for training and to ensure that all possible outcomes and complications are prepared for before the actual launch day. The code being tested is the Programmable Logic Controller Interface (PLCIF) code, the component responsible for transferring the information from the models to the model Programmable Logic Controllers (PLCs), basic computers that are used for very simple tasks.
Constellation Program Electrical Ground Support Equipment Research and Development
NASA Technical Reports Server (NTRS)
McCoy, Keegan S.
2010-01-01
At the Kennedy Space Center, I engaged in the research and development of electrical ground support equipment for NASA's Constellation Program. Timing characteristics playa crucial role in ground support communications. Latency and jitter are two problems that must be understood so that communications are timely and consistent within the Kennedy Ground Control System (KGCS). I conducted latency and jitter tests using Alien-Bradley programmable logic controllers (PLCs) so that these two intrinsic network properties can be reduced. Time stamping and clock synchronization also play significant roles in launch processing and operations. Using RSLogix 5000 project files and Wireshark network protocol analyzing software, I verified master/slave PLC Ethernet module clock synchronization, master/slave IEEE 1588 communications, and time stamping capabilities. All of the timing and synchronization test results are useful in assessing the current KGCS operational level and determining improvements for the future.
Muñoz, C; Young, H; Antileo, C; Bornhardt, C
2009-01-01
This paper presents a sliding mode controller (SMC) for dissolved oxygen (DO) in an integrated nitrogen removal process carried out in a suspended biomass sequencing batch reactor (SBR). The SMC performance was compared against an auto-tuning PI controller with parameters adjusted at the beginning of the batch cycle. A method for cancelling the slow DO sensor dynamics was implemented by using a first order model of the sensor. Tests in a lab-scale reactor showed that the SMC offers a better disturbance rejection capability than the auto-tuning PI controller, furthermore providing reasonable performance in a wide range of operation. Thus, SMC becomes an effective robust nonlinear tool to the DO control in this process, being also simple from a computational point of view, allowing its implementation in devices such as industrial programmable logic controllers (PLCs).
Developing a PLC-friendly state machine model: lessons learned
NASA Astrophysics Data System (ADS)
Pessemier, Wim; Deconinck, Geert; Raskin, Gert; Saey, Philippe; Van Winckel, Hans
2014-07-01
Modern Programmable Logic Controllers (PLCs) have become an attractive platform for controlling real-time aspects of astronomical telescopes and instruments due to their increased versatility, performance and standardization. Likewise, vendor-neutral middleware technologies such as OPC Unified Architecture (OPC UA) have recently demonstrated that they can greatly facilitate the integration of these industrial platforms into the overall control system. Many practical questions arise, however, when building multi-tiered control systems that consist of PLCs for low level control, and conventional software and platforms for higher level control. How should the PLC software be structured, so that it can rely on well-known programming paradigms on the one hand, and be mapped to a well-organized OPC UA interface on the other hand? Which programming languages of the IEC 61131-3 standard closely match the problem domains of the abstraction levels within this structure? How can the recent additions to the standard (such as the support for namespaces and object-oriented extensions) facilitate a model based development approach? To what degree can our applications already take advantage of the more advanced parts of the OPC UA standard, such as the high expressiveness of the semantic modeling language that it defines, or the support for events, aggregation of data, automatic discovery, ... ? What are the timing and concurrency problems to be expected for the higher level tiers of the control system due to the cyclic execution of control and communication tasks by the PLCs? We try to answer these questions by demonstrating a semantic state machine model that can readily be implemented using IEC 61131 and OPC UA. One that does not aim to capture all possible states of a system, but rather one that attempts to organize the course-grained structure and behaviour of a system. In this paper we focus on the intricacies of this seemingly simple task, and on the lessons that we've learned during the development process of such a "PLC-friendly" state machine model.
Master Console System Monitoring and Control Development
NASA Technical Reports Server (NTRS)
Brooks, Russell A.
2013-01-01
The Master Console internship during the summer of 2013 involved the development of firing room displays and support applications at the John F. Kennedy Space Center (KSC). This position was with the Master Console Product Group (MCPG) on the Launch Control System (LCS) project. This project is responsible for the System Monitoring and Control (SMC) and Record and Retrieval (R&R) of launch operations data. The Master Console is responsible for: loading the correct software into each of the remaining consoles in the firing room, connecting the proper data paths to and from the launch vehicle and all ground support equipment, and initializing the entire firing room system to begin processing. During my internship, I created control scripts using the Application Control Language (ACL) to analyze the health and status of Kennedy Ground Control System (KGCS) programmable logic controllers (PLCs). This application provides a system health and status display I created with summarized data for use by Master Console Operators (MCO) to monitor and verify the integrity of KGCS subsystems.
NASA Astrophysics Data System (ADS)
Kiekebusch, Mario J.; Lucuix, Christian; Erm, Toomas M.; Chiozzi, Gianluca; Zamparelli, Michele; Kern, Lothar; Brast, Roland; Pirani, Werther; Reiss, Roland; Popovic, Dan; Knudstrup, Jens; Duchateau, Michel; Sandrock, Stefan; Di Lieto, Nicola
2014-07-01
ESO is currently in the final phase of the standardization process for PC-based Programmable Logical Controllers (PLCs) as the new platform for the development of control systems for future VLT/VLTI instruments. The standard solution used until now consists of a Local Control Unit (LCU), a VME-based system having a CPU and commercial and proprietary boards. This system includes several layers of software and many thousands of lines of code developed and maintained in house. LCUs have been used for several years as the interface to control instrument functions but now are being replaced by commercial off-the-shelf (COTS) systems based on BECKHOFF Embedded PCs and the EtherCAT fieldbus. ESO is working on the completion of the software framework that enables a seamless integration into the VLT control system in order to be ready to support upcoming instruments like ESPRESSO and ERIS, that will be the first fully VLT compliant instruments using the new standard. The technology evaluation and standardization process has been a long and combined effort of various engineering disciplines like electronics, control and software, working together to define a solution that meets the requirements and minimizes the impact on the observatory operations and maintenance. This paper presents the challenges of the standardization process and the steps involved in such a change. It provides a technical overview of how industrial standards like EtherCAT, OPC-UA, PLCOpen MC and TwinCAT can be used to replace LCU features in various areas like software engineering and programming languages, motion control, time synchronization and astronomical tracking.
Knowledge-based engineering of a PLC controlled telescope
NASA Astrophysics Data System (ADS)
Pessemier, Wim; Raskin, Gert; Saey, Philippe; Van Winckel, Hans; Deconinck, Geert
2016-08-01
As the new control system of the Mercator Telescope is being finalized, we can review some technologies and design methodologies that are advantageous, despite their relative uncommonness in astronomical instrumentation. Particular for the Mercator Telescope is that it is controlled by a single high-end soft-PLC (Programmable Logic Controller). Using off-the-shelf components only, our distributed embedded system controls all subsystems of the telescope such as the pneumatic primary mirror support, the hydrostatic bearing, the telescope axes, the dome, the safety system, and so on. We show how real-time application logic can be written conveniently in typical PLC languages (IEC 61131-3) and in C++ (to implement the pointing kernel) using the commercial TwinCAT 3 programming environment. This software processes the inputs and outputs of the distributed system in real-time via an observatory-wide EtherCAT network, which is synchronized with high precision to an IEEE 1588 (PTP, Precision Time Protocol) time reference clock. Taking full advantage of the ability of soft-PLCs to run both real-time and non real-time software, the same device also hosts the most important user interfaces (HMIs or Human Machine Interfaces) and communication servers (OPC UA for process data, FTP for XML configuration data, and VNC for remote control). To manage the complexity of the system and to streamline the development process, we show how most of the software, electronics and systems engineering aspects of the control system have been modeled as a set of scripts written in a Domain Specific Language (DSL). When executed, these scripts populate a Knowledge Base (KB) which can be queried to retrieve specific information. By feeding the results of those queries to a template system, we were able to generate very detailed "browsable" web-based documentation about the system, but also PLC software code, Python client code, model verification reports, etc. The aim of this paper is to demonstrate the added value that technologies such as soft-PLCs and DSL-scripts and design methodologies such as knowledge-based engineering can bring to astronomical instrumentation.
Refurbishment and Automation of the Thermal/Vacuum Facilities at the Goddard Space Flight Center
NASA Technical Reports Server (NTRS)
Donohue, John T.; Johnson, Chris; Ogden, Rick; Sushon, Janet
1998-01-01
The thermal/vacuum facilities located at the Goddard Space Flight Center (GSFC) have supported both manned and unmanned space flight since the 1960s. Of the 11 facilities, currently 10 of the systems are scheduled for refurbishment and/or replacement as part of a 5-year implementation. Expected return on investment includes the reduction in test schedules, improvements in the safety of facility operations, reduction in the complexity of a test and the reduction in personnel support required for a test. Additionally, GSFC will become a global resource renowned for expertise in thermal engineering, mechanical engineering and for the automation of thermal/vacuum facilities and thermal/vacuum tests. Automation of the thermal/vacuum facilities includes the utilization of Programmable Logic Controllers (PLCs) and the use of Supervisory Control and Data Acquisition (SCADA) systems. These components allow the computer control and automation of mechanical components such as valves and pumps. In some cases, the chamber and chamber shroud require complete replacement while others require only mechanical component retrofit or replacement. The project of refurbishment and automation began in 1996 and has resulted in the computer control of one Facility (Facility #225) and the integration of electronically controlled devices and PLCs within several other facilities. Facility 225 has been successfully controlled by PLC and SCADA for over one year. Insignificant anomalies have occurred and were resolved with minimal impact to testing and operations. The amount of work remaining to be performed will occur over the next four to five years. Fiscal year 1998 includes the complete refurbishment of one facility, computer control of the thermal systems in two facilities, implementation of SCADA and PLC systems to support multiple facilities and the implementation of a Database server to allow efficient test management and data analysis.
External Verification of SCADA System Embedded Controller Firmware
2012-03-01
microprocessor and read-only memory (ROM) or flash memory for storing firmware and control logic [5],[8]. A PLC typically has three software levels as shown in...implementing different firmware. Because PLCs are in effect a microprocessor device, an analysis of the current research on embedded devices is important...Electronics Engineers (IEEE) published a 15 best practices guide for firmware control on microprocessors [44]. IEEE suggests that microprocessors
Software Assurance of PLCs Training Course
NASA Technical Reports Server (NTRS)
Threatt, Jamarr
2004-01-01
Being heavily visually-oriented, I am a firm believer in communication and conveying emotions through the art of color, motion, and transformation. A four-part online training course was created in PowerPoint and needed to be translated over into a Flash format. Issues with the Powerpoint were that the size of the files caused noticeable delays when placed online, there were compatibility issues, and from a composition and design perspective, color schemes and layout left much to be desired. High contrast, pixilated yellow text spiraling and flying on to a background of overly rich hues of blue with cheesy gradient patterns was just not appeasing to my eye, along with the menu directory buttons located at the top resembling blue pills of NyQuil on top of a stale gray border that had nothing to do with the background. The course itself is extremely broad and verbose, and will get monotonous very soon after starting. Moving about the course was very cumbersome as well. efficient by drastically reducing the size (The file size of all four parts of the actual course combined will ultimately not even be a fifth as big as one part of the original PowerPoint alone!); along with that, the course was made to be more interactive and user-friendly, as well as pleasing to the eye. Upon being viewed by fellow co-workers, nothing but positive feedback has been received. When beginning the presentation, onscreen comes a 3' 2" chubby, balding professor, who is a master in his knowledge of Programmable Logic Controllers (PLCs). He introduces himself and presents all of his vast knowledge over PLCs in a fun and innovative manner, making it much easier to acquire the information presented. A Scene Selection feature has been added making it a lot easier to jump from part to part and the back and forth arrows are much easier to utilize, and they are both less obtrusive than its PowerPoint predecessor. The user can also go at their pace, as the presentation pauses after at the end of each statement. computer animation, it was.. .still. ..animation done on a computer. I was able to incorporate my artistic talent and intuitive creativity into it, one thing I am very proficient at doing when it comes to what I do and what I will do in my profession as an artist/computer animator. At first, I felt that there was no place for an artist within a faculty of scientists, engineers, chemists, mathematicians, and programmers, but I managed to fit in quite successfully. My task was to convert the course into a Flash format, which would make it much more My project surprisingly somewhat dealt with my field of interest-though it was not
Forging Professional Learning Communities: The Role of External Agency
ERIC Educational Resources Information Center
Sperandio, Jill; Kong, Peggy A.
2018-01-01
This article explored the effects of external agency on the establishment of professional learning communities (PLCs). The research was undertaken in the context of schools that have chosen to adopt the Primary Years Programme (PYP) of the International Baccalaureate (IB) worldwide. The study employed a two-stage qualitative sequential design…
Deployable robotic woven wire structures and joints for space applications
NASA Technical Reports Server (NTRS)
Shahinpoor, MO; Smith, Bradford
1991-01-01
Deployable robotic structures are basically expandable and contractable structures that may be transported or launched to space in a compact form. These structures may then be intelligently deployed by suitable actuators. The deployment may also be done by means of either airbag or spring-loaded typed mechanisms. The actuators may be pneumatic, hydraulic, ball-screw type, or electromagnetic. The means to trigger actuation may be on-board EPROMS, programmable logic controllers (PLCs) that trigger actuation based on some input caused by the placement of the structure in the space environment. The actuation may also be performed remotely by suitable remote triggering devices. Several deployable woven wire structures are examined. These woven wire structures possess a unique form of joint, the woven wire joint, which is capable of moving and changing its position and orientation with respect to the structure itself. Due to the highly dynamic and articulate nature of these joints the 3-D structures built using them are uniquely and highly expandable, deployable, and dynamic. The 3-D structure naturally gives rise to a new generation of deployable three-dimensional spatial structures.
Simulation Environment Synchronizing Real Equipment for Manufacturing Cell
NASA Astrophysics Data System (ADS)
Inukai, Toshihiro; Hibino, Hironori; Fukuda, Yoshiro
Recently, manufacturing industries face various problems such as shorter product life cycle, more diversified customer needs. In this situation, it is very important to reduce lead-time of manufacturing system constructions. At the manufacturing system implementation stage, it is important to make and evaluate facility control programs for a manufacturing cell, such as ladder programs for programmable logical controllers (PLCs) rapidly. However, before the manufacturing systems are implemented, methods to evaluate the facility control programs for the equipment while mixing and synchronizing real equipment and virtual factory models on the computers have not been developed. This difficulty is caused by the complexity of the manufacturing system composed of a great variety of equipment, and stopped precise and rapid support of a manufacturing engineering process. In this paper, a manufacturing engineering environment (MEE) to support manufacturing engineering processes using simulation technologies is proposed. MEE consists of a manufacturing cell simulation environment (MCSE) and a distributed simulation environment (DSE). MCSE, which consists of a manufacturing cell simulator and a soft-wiring system, is emphatically proposed in detail. MCSE realizes making and evaluating facility control programs by using virtual factory models on computers before manufacturing systems are implemented.
An experimental comparative analyse between three low capacity PLCs
NASA Astrophysics Data System (ADS)
Popa, G. N.; Diniş, C. M.; lagăr, A.; Popa, I.
2017-01-01
PLCs are used increasingly more often in industrial applications and beyond. PLCs from different companies involved different programming languages. Some of the PLCs can be programmed in all languages, while others do not. For three types of PLCs was made an application for a traffic light with priority. PLCs usually have a general and a special set of instructions that only some of these are found from a PLC to another. Programs were made with specific instruction set of respectively PLC. The programs were carried out in three languages. For a case study, it makes a comparative analysis between three programming languages.
Establishment and characterization of a telomerase immortalized porcine luteal cells.
Zhang, Liang; Huang, Yong; Wang, Zhenyu; Luo, Xiaomao; Zhang, Hongling; Du, Qian; Chang, Lingling; Zhao, Xiaomin; Tong, Dewen
2017-05-01
Luteal cells play a crucial role in pregnancy through secreting progesterone to maintain pregnancy and support of fetus. However, low cellular yields and inability to passage primary porcine luteal cells (PLCs) in vitro limit the luteal cell study. Therefore, developing an immortalized porcine luteal cell line is necessary for studying luteal cells activity and function in different diseases. In this study, primary PLCs were obtained from gilts at day 30 to day 50 of gestation and immortalized by human telomerase reverse transcriptase (hTERT). The porcine corpus luteal cell line (hTERT-PLCs) expressed hTERT gene steady, maintained high hTERT activity and normal karyotype. The phase contrast microscope and transmission electron microscope observation showed primary PLCs and hTERT-PLCs were polygonal and exhibited abundant mitochondria, smooth endoplasmic reticulum and lipid droplets. 3β hydroxysteroid dehydrogenase (3βHSD) and Oil-Red-O staining showed that hTERT-PLCs at passage 30 and 50 were similar to primary PLCs. The hTERT-PLCs expressed steroidogenesis-related proteins, enzymes and receptors, such as steroidogenic acute regulatory protein, P450 cholesterol side-chain cleavage, 3βHSD, 20αHSD, luteinizing hormone receptor, progesterone receptor, prolactin receptor, estrogen receptorα/β, as well as primary PLCs. Consequently, hTERT-PLCs could secret progesterone and exhibited similar responses to luteinizing hormone and prostaglandin F2α as primary PLCs. In addition, the hTERT-PLCs did not show neoplastic transformation or anchorage independent growth. In summary, we developed an immortalized porcine luteal cell line which maintained its originally morphological, biological and functional characteristics. Copyright © 2017 Elsevier Inc. All rights reserved.
ERIC Educational Resources Information Center
Zhu, Yi; Weng, T.; Cheng, Chung-Kuan
2009-01-01
Incorporating programmable logic devices (PLD) in digital design courses has become increasingly popular. The advantages of using PLDs, such as complex programmable logic devices (CPLDs) and field programmable gate arrays (FPGA), have been discussed before. However, previous studies have focused on the experiences from the point of view of the…
Programmable Logic Controllers.
ERIC Educational Resources Information Center
Insolia, Gerard; Anderson, Kathleen
This document contains a 40-hour course in programmable logic controllers (PLC), developed for a business-industry technology resource center for firms in eastern Pennsylvania by Northampton Community College. The 10 units of the course cover the following: (1) introduction to programmable logic controllers; (2) DOS primer; (3) prerequisite…
Can your software engineer program your PLC?
NASA Astrophysics Data System (ADS)
Borrowman, Alastair J.; Taylor, Philip
2016-07-01
The use of Programmable Logic Controllers (PLCs) in the control of large physics experiments is ubiquitous1, 2, 3. The programming of these controllers is normally the domain of engineers with a background in electronics, this paper introduces PLC program development from the software engineer's perspective. PLC programs provide the link between control software running on PC architecture systems and physical hardware controlled and monitored by digital and analog signals. The higher-level software running on the PC is typically responsible for accepting operator input and from this deciding when and how hardware connected to the PLC is controlled. The PLC accepts demands from the PC, considers the current state of its connected hardware and if correct to do so (based upon interlocks or other constraints) adjusts its hardware output signals appropriately for the PC's demands. A published ICD (Interface Control Document) defines the PLC memory locations available to be written and read by the PC to control and monitor the hardware. Historically the method of programming PLCs has been ladder diagrams that closely resemble circuit diagrams, however, PLC manufacturers nowadays also provide, and promote, the use of higher-level programming languages4. Based on techniques used in the development of high-level PC software to control PLCs for multiple telescopes, this paper examines the development of PLC programs to operate the hardware of a medical cyclotron beamline controlled from a PC using the Experimental Physics and Industrial Control System (EPICS), which is also widely used in telescope control5, 6, 7. The PLC used is the new generation Siemens S7-1200 programmed using Siemens Pascal based Structured Control Language (SCL), which is their implementation of Structured Text (ST). The approach described is that from a software engineer's perspective, utilising Siemens Totally Integrated Automation (TIA) Portal integrated development environment (IDE) to create modular PLC programs based upon reusable functions capable of being unit tested without the PLC connected to hardware. Emphasis has been placed on designing an interface between EPICS and SCL that enforces correct operation of hardware through stringent separation of PC accessible PLC memory and hardware I/O addresses used only by the PLC. The paper also introduces the method used to automate the creation, from the same source document, the PLC memory structure (tag) definitions (defining memory used to access hardware I/O and that accessed by the PC) and creation of the PC program data structures (EPICS database records) used to access the permitted PLC addresses. From direct experience this paper demonstrates the advantages of PLC program development being shared between electronic and software engineers, to enable use of the most appropriate processes from both the perspective of the hardware and the higher-level software used to control it.
General purpose programmable accelerator board
Robertson, Perry J.; Witzke, Edward L.
2001-01-01
A general purpose accelerator board and acceleration method comprising use of: one or more programmable logic devices; a plurality of memory blocks; bus interface for communicating data between the memory blocks and devices external to the board; and dynamic programming capabilities for providing logic to the programmable logic device to be executed on data in the memory blocks.
Software Safety Assurance of Programmable Logic
NASA Technical Reports Server (NTRS)
Berens, Kalynnda
2002-01-01
Programmable Logic (PLC, FPGA, ASIC) devices are hybrids - hardware devices that are designed and programmed like software. As such, they fall in an assurance gray area. Programmable Logic is usually tested and verified as hardware, and the software aspects are ignored, potentially leading to safety or mission success concerns. The objective of this proposal is to first determine where and how Programmable Logic (PL) is used within NASA and document the current methods of assurance. Once that is known, raise awareness of the PL software aspects within the NASA engineering community and provide guidance for the use and assurance of PL form a software perspective.
Programmable pulse generator based on programmable logic and direct digital synthesis.
Suchenek, M; Starecki, T
2012-12-01
The paper presents a new approach of pulse generation which results in both wide range tunability and high accuracy of the output pulses. The concept is based on the use of programmable logic and direct digital synthesis. The programmable logic works as a set of programmable counters, while direct digital synthesis (DDS) as the clock source. Use of DDS as the clock source results in stability of the output pulses comparable to the stability of crystal oscillators and quasi-continuous tuning of the output frequency.
Alves, P; Hugo, A A; Szymanowski, F; Tymczyszyn, E E; Pérez, P F; Coelho, J F J; Simões, P N; Gómez-Zavaglia, A
2014-11-01
The physicochemical characterization of polymer liposome complexes (PLCs) prepared with lipids of lactic acid bacteria and poly(N,N-dimethylaminoethyl methacrylate) covalently bound to cholesterol (CHO-PDMAEMA) was carried out in an integrated approach, including their stability upon preservation and incorporation into eukaryotic cells. PLCs were prepared with different polymer:lipid molar ratios (0, 0.05 and 0.10). Zeta potential, particle size distribution and polydispersity index were determined. The optimal polymer:lipid ratio and the stability of both bare liposomes and PLCs were evaluated at 37 °C and at different pHs, as well as after storage at 4 °C, -80 °C and freeze-drying in the presence or absence of trehalose 250 mM. Internalization of PLCs by eukaryotic cells was assessed to give a complete picture of the system. Incorporation of CHO-PDMAEMA onto bacterial lipids (ratio 0.05 and 0.10) led to stabilization at 37 °C and pH 7. A slight decrease of pH led to their strong destabilization. Bacteria PLCs showed to be more stable than lecithin (LEC) PLCs (used for comparison) upon preservation at 4 and -80 °C. The harmful nature of the preservation processes led to a strong decrease in the stability of PLCs, bacterial formulations being more stable than LEC PLCs. The addition of trehalose to the suspension of liposomes stabilized LEC PLC and did not have effect on bacterial PLCs. In vitro studies on Raw 264.7 and Caco-2/TC7 cells demonstrated an efficient incorporation of PLCs into the cells. Preparations with higher stability were the ones that showed a better cell-uptake. The nature of the lipid composition is determinant for the stability of PLCs. Lipids from lactic acid bacteria are composed of glycolipids and phospholipids like cardiolipin and phosphatidylglycerol. The presence of negatively charged lipids strongly improves the interaction with the positively charged CHO-PDMAEMA, thus stabilizing liposomes. In addition, glycolipids and phosphatidylglycerol act as intrinsic protectants of PLCs upon preservation. This particular lipid composition of lactic acid bacteria makes them natural formulations potentially useful as drug delivery systems. Copyright © 2014 Elsevier B.V. All rights reserved.
Implementing neural nets with programmable logic
NASA Technical Reports Server (NTRS)
Vidal, Jacques J.
1988-01-01
Networks of Boolean programmable logic modules are presented as one purely digital class of artificial neural nets. The approach contrasts with the continuous analog framework usually suggested. Programmable logic networks are capable of handling many neural-net applications. They avoid some of the limitations of threshold logic networks and present distinct opportunities. The network nodes are called dynamically programmable logic modules. They can be implemented with digitally controlled demultiplexers. Each node performs a Boolean function of its inputs which can be dynamically assigned. The overall network is therefore a combinational circuit and its outputs are Boolean global functions of the network's input variables. The approach offers definite advantages for VLSI implementation, namely, a regular architecture with limited connectivity, simplicity of the control machinery, natural modularity, and the support of a mature technology.
All optical programmable logic array (PLA)
NASA Astrophysics Data System (ADS)
Hiluf, Dawit
2018-03-01
A programmable logic array (PLA) is an integrated circuit (IC) logic device that can be reconfigured to implement various kinds of combinational logic circuits. The device has a number of AND and OR gates which are linked together to give output or further combined with more gates or logic circuits. This work presents the realization of PLAs via the physics of a three level system interacting with light. A programmable logic array is designed such that a number of different logical functions can be combined as a sum-of-product or product-of-sum form. We present an all optical PLAs with the aid of laser light and observables of quantum systems, where encoded information can be considered as memory chip. The dynamics of the physical system is investigated using Lie algebra approach.
Evolution of the VLT instrument control system toward industry standards
NASA Astrophysics Data System (ADS)
Kiekebusch, Mario J.; Chiozzi, Gianluca; Knudstrup, Jens; Popovic, Dan; Zins, Gerard
2010-07-01
The VLT control system is a large distributed system consisting of Linux Workstations providing the high level coordination and interfaces to the users, and VME-based Local Control Units (LCU's) running the VxWorks real-time operating system with commercial and proprietary boards acting as the interface to the instrument functions. After more than 10 years of VLT operations, some of the applied technologies used by the astronomical instruments are being discontinued making it difficult to find adequate hardware for future projects. In order to deal with this obsolescence, the VLT Instrumentation Framework is being extended to adopt well established Commercial Off The Shelf (COTS) components connected through industry standard fieldbuses. This ensures a flexible state of the art hardware configuration for the next generation VLT instruments allowing the access to instrument devices via more compact and simpler control units like PC-based Programmable Logical Controllers (PLC's). It also makes it possible to control devices directly from the Instrument Workstation through a normal Ethernet connection. This paper outlines the requirements that motivated this work, as well as the architecture and the design of the framework extension. In addition, it describes the preliminary results on a use case which is a VLTI visitor instrument used as a pilot project to validate the concepts and the suitability of some COTS products like a PC-based PLCs, EtherCAT8 and OPC UA6 as solutions for instrument control.
Relay Protection and Automation Systems Based on Programmable Logic Integrated Circuits
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lashin, A. V., E-mail: LashinAV@lhp.ru; Kozyrev, A. V.
One of the most promising forms of developing the apparatus part of relay protection and automation devices is considered. The advantages of choosing programmable logic integrated circuits to obtain adaptive technological algorithms in power system protection and control systems are pointed out. The technical difficulties in the problems which today stand in the way of using relay protection and automation systems are indicated and a new technology for solving these problems is presented. Particular attention is devoted to the possibility of reconfiguring the logic of these devices, using programmable logic integrated circuits.
Implementing Professional Learning Communities in Small High Schools
ERIC Educational Resources Information Center
Eichelkraut, Jeff P.
2017-01-01
Professional learning communities (PLCs) are collaborative teacher groups that focus on learning and continual improvement. Establishing PLCs can be a challenging endeavor, especially in smaller schools. Smaller schools employ fewer staff members, limiting opportunities for collaboration. This dissertation examined the implementation of PLCs in…
ESR1 inhibits hCG-induced steroidogenesis and proliferation of progenitor Leydig cells in mice.
Oh, Yeong Seok; Koh, Il Kyoo; Choi, Bomi; Gye, Myung Chan
2017-03-07
Oestrogen is an important regulator in reproduction. To understand the role of oestrogen receptor 1 (ESR1) in Leydig cells, we investigated the expression of ESR1 in mouse Leydig cells during postnatal development and the effects of oestrogen on steroidogenesis and proliferation of progenitor Leydig cells (PLCs). In Leydig cells, the ESR1 expression was low at birth, increased until postnatal day 14 at which PLCs were predominant, and then decreased until adulthood. In foetal Leydig cells, ESR1 immunoreactivity increased from birth to postnatal day 14. These suggest that ESR1 is a potential biomarker of Leydig cell development. In PLCs, 17β-estradiol and the ESR1-selective agonist propylpyrazoletriol suppressed human chorionic gonadotropin (hCG)-induced progesterone production and steroidogenic gene expression. The ESR2-selective agonist diarylpropionitrile did not affect steroidogenesis. In PLCs from Esr1 knockout mice, hCG-stimulated steroidogenesis was not suppressed by 17β-estradiol, suggesting that oestrogen inhibits PLC steroidogenesis via ESR1. 17β-estradiol, propylpyrazoletriol, and diarylpropionitrile decreased bromodeoxyuridine uptake in PLCs in the neonatal mice. In cultured PLCs, 17β-estradiol, propylpyrazoletriol, and diarylpropionitrile reduced hCG-stimulated Ki67 and Pcna mRNA expression and the number of KI67-positive PLCs, suggesting that oestrogen inhibits PLC proliferation via both ESR1 and ESR2. In PLCs, ESR1 mediates the oestrogen-induced negative regulation of steroidogenesis and proliferation.
ESR1 inhibits hCG-induced steroidogenesis and proliferation of progenitor Leydig cells in mice
Oh, Yeong Seok; Koh, Il Kyoo; Choi, Bomi; Gye, Myung Chan
2017-01-01
Oestrogen is an important regulator in reproduction. To understand the role of oestrogen receptor 1 (ESR1) in Leydig cells, we investigated the expression of ESR1 in mouse Leydig cells during postnatal development and the effects of oestrogen on steroidogenesis and proliferation of progenitor Leydig cells (PLCs). In Leydig cells, the ESR1 expression was low at birth, increased until postnatal day 14 at which PLCs were predominant, and then decreased until adulthood. In foetal Leydig cells, ESR1 immunoreactivity increased from birth to postnatal day 14. These suggest that ESR1 is a potential biomarker of Leydig cell development. In PLCs, 17β-estradiol and the ESR1-selective agonist propylpyrazoletriol suppressed human chorionic gonadotropin (hCG)-induced progesterone production and steroidogenic gene expression. The ESR2-selective agonist diarylpropionitrile did not affect steroidogenesis. In PLCs from Esr1 knockout mice, hCG-stimulated steroidogenesis was not suppressed by 17β-estradiol, suggesting that oestrogen inhibits PLC steroidogenesis via ESR1. 17β-estradiol, propylpyrazoletriol, and diarylpropionitrile decreased bromodeoxyuridine uptake in PLCs in the neonatal mice. In cultured PLCs, 17β-estradiol, propylpyrazoletriol, and diarylpropionitrile reduced hCG-stimulated Ki67 and Pcna mRNA expression and the number of KI67-positive PLCs, suggesting that oestrogen inhibits PLC proliferation via both ESR1 and ESR2. In PLCs, ESR1 mediates the oestrogen-induced negative regulation of steroidogenesis and proliferation. PMID:28266530
Design of a Ferroelectric Programmable Logic Gate Array
NASA Technical Reports Server (NTRS)
MacLeod, Todd C.; Ho, Fat Duen
2003-01-01
A programmable logic gate array has been designed utilizing ferroelectric field effect transistors. The design has only a small number of gates, but this could be scaled up to a more useful size. Using FFET's in a logic array gives several advantages. First, it allows real-time programmability to the array to give high speed reconfiguration. It also allows the array to be configured nearly an unlimited number of times, unlike a FLASH FPGA. Finally, the Ferroelectric Programmable Logic Gate Array (FPLGA) can be implemented using a smaller number of transistors because of the inherent logic characteristics of an FFET. The device was only designed and modeled using Spice models of the circuit, including the FFET. The actual device was not produced. The design consists of a small array of NAND and NOR logic gates. Other gates could easily be produced. They are linked by FFET's that control the logic flow. Timing and logic tables have been produced showing the array can produce a variety of logic combinations at a real time usable speed. This device could be a prototype for a device that could be put into imbedded systems that need the high speed of hardware implementation of logic and the complexity to need to change the logic algorithm. Because of the non-volatile nature of the FFET, it would also be useful in situations that needed to program a logic array once and use it repeatedly after the power has been shut off.
Optical reversible programmable Boolean logic unit.
Chattopadhyay, Tanay
2012-07-20
Computing with reversibility is the only way to avoid dissipation of energy associated with bit erase. So, a reversible microprocessor is required for future computing. In this paper, a design of a simple all-optical reversible programmable processor is proposed using a polarizing beam splitter, liquid crystal-phase spatial light modulators, a half-wave plate, and plane mirrors. This circuit can perform 16 logical operations according to three programming inputs. Also, inputs can be easily recovered from the outputs. It is named the "reversible programmable Boolean logic unit (RPBLU)." The logic unit is the basic building block of many complex computational operations. Hence the design is important in sense. Two orthogonally polarized lights are defined here as two logical states, respectively.
Strategic Accountability Is Key to Making PLCs Effective
ERIC Educational Resources Information Center
Easton, Lois Brown
2017-01-01
Professional Learning Communities (PLCs) are often criticized for failing to focus on real problems of teaching and learning and for failing to deliver improvement. That is where accountability comes into play. Strategic accountability distinguishes PLCs that are effective from those that are not. Everyone knows what accountability is, but the…
Assessing Child and Adolescent Pragmatic Language Competencies: Toward Evidence-Based Assessments
ERIC Educational Resources Information Center
Russell, Robert L.; Grizzle, Kenneth L.
2008-01-01
Using language appropriately and effectively in social contexts requires pragmatic language competencies (PLCs). Increasingly, deficits in PLCs are linked to child and adolescent disorders, including autism spectrum, externalizing, and internalizing disorders. As the role of PLCs expands in diagnosis and treatment of developmental psychopathology,…
Programmable hardware for reconfigurable computing systems
NASA Astrophysics Data System (ADS)
Smith, Stephen
1996-10-01
In 1945 the work of J. von Neumann and H. Goldstein created the principal architecture for electronic computation that has now lasted fifty years. Nevertheless alternative architectures have been created that have computational capability, for special tasks, far beyond that feasible with von Neumann machines. The emergence of high capacity programmable logic devices has made the realization of these architectures practical. The original ENIAC and EDVAC machines were conceived to solve special mathematical problems that were far from today's concept of 'killer applications.' In a similar vein programmable hardware computation is being used today to solve unique mathematical problems. Our programmable hardware activity is focused on the research and development of novel computational systems based upon the reconfigurability of our programmable logic devices. We explore our programmable logic architectures and their implications for programmable hardware. One programmable hardware board implementation is detailed.
ERIC Educational Resources Information Center
Sleegers, Peter; den Brok, Perry; Verbiest, Eric; Moolenaar, Nienke M.; Daly, Alan J.
2013-01-01
Despite the popularity of professional learning communities (PLCs) among researchers, practitioners, and educational policy makers, studies on PLCs differ significantly on the dimensions and capacities used to conceptualize them. Further, the interrelatedness of different dimensions and capacities within PLCs is not often well conceived nor…
Exploring the Characteristics of Professional Learning Communities in China: A Mixed-Method Study
ERIC Educational Resources Information Center
Zhang, Jia; Pang, Nicholas Sun-Keung
2016-01-01
This mixed-method study explored the characteristics of professional learning communities (PLCs) in Chinese schools. Informed by the existing literature on PLCs, the authors conducted a questionnaire survey of teachers in seven schools in Shanghai to explore the characteristics of Chinese PLCs. Follow-up qualitative interviews were also conducted…
Field-Free Programmable Spin Logics via Chirality-Reversible Spin-Orbit Torque Switching.
Wang, Xiao; Wan, Caihua; Kong, Wenjie; Zhang, Xuan; Xing, Yaowen; Fang, Chi; Tao, Bingshan; Yang, Wenlong; Huang, Li; Wu, Hao; Irfan, Muhammad; Han, Xiufeng
2018-06-21
Spin-orbit torque (SOT)-induced magnetization switching exhibits chirality (clockwise or counterclockwise), which offers the prospect of programmable spin-logic devices integrating nonvolatile spintronic memory cells with logic functions. Chirality is usually fixed by an applied or effective magnetic field in reported studies. Herein, utilizing an in-plane magnetic layer that is also switchable by SOT, the chirality of a perpendicular magnetic layer that is exchange-coupled with the in-plane layer can be reversed in a purely electrical way. In a single Hall bar device designed from this multilayer structure, three logic gates including AND, NAND, and NOT are reconfigured, which opens a gateway toward practical programmable spin-logic devices. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Teaching Discrete and Programmable Logic Design Techniques Using a Single Laboratory Board
ERIC Educational Resources Information Center
Debiec, P.; Byczuk, M.
2011-01-01
Programmable logic devices (PLDs) are used at many universities in introductory digital logic laboratories, where kits containing a single high-capacity PLD replace "standard" sets containing breadboards, wires, and small- or medium-scale integration (SSI/MSI) chips. From the pedagogical point of view, two problems arise in these…
In Praise of Isolation: Who Says PLCs Are a Better Way?
ERIC Educational Resources Information Center
O'Keeffe, James
2012-01-01
In praise of isolation: Who says professional learning communities (PLCs) are a better way? The author says the PLC trend is but the latest education fad that is not helping teachers or students. PLCs, says the author, represents an administrative, clinical ideal of collaboration. He blames legions of high-paid consultants, and says that all along…
ERIC Educational Resources Information Center
Pang, Nicholas Sun-Keung; Wang, Ting; Leung, Zoe Lai-Mei
2016-01-01
This study explored the characteristics of professional learning communities (PLCs) in Hong Kong primary schools. It investigated the profiles of the strengths of professional learning community in schools under study and particularly examined the practices in schools which were identified as strong PLCs. It extends research on PLCs in the Hong…
University-Urban High School Partnership: Math and Science Professional Learning Communities
ERIC Educational Resources Information Center
ndunda, mutindi; Van Sickle, Meta; Perry, Lindsay; Capelloni, Alison
2017-01-01
This study focused on science and math professional learning communities (PLCs) that were implemented through a university-urban high school partnership. These PLCs were part of mandated school-wide, content-based PLCs implemented as part of the reform efforts initiated in an urban school to address the school's failure to meet Adequate Yearly…
PLCs on Steroids: Moving Teacher Practice to the Center of Data Teams
ERIC Educational Resources Information Center
Wasta, Michael J.
2017-01-01
Research on educators' professional learning communities (PLCs) suggest that while they often help teachers to make sense of student performance data, they tend to spend relatively little time studying what teachers actually do in the classroom. Evidence suggests that, given modest amounts of guidance and support, PLCs can collect useful data on…
Documenting and Examining Practices in Creating Learning Communities: Exemplars and Non-Exemplars.
ERIC Educational Resources Information Center
Hipp, Kristine A.; Huffman, Jane B.
Though promising as an implement for school reform, few professional learning centers (PLCs) have turned the vision into reality. This paper looks at how PLCs develop and maintain momentum. It examines and documents efforts in schools actively engaged in creating PLCs based on Hord's model. Hord's model employs external change agents, or…
A Situative Perspective on Developing Writing Pedagogy in a Teacher Professional Learning Community
ERIC Educational Resources Information Center
Pella, Shannon
2011-01-01
The bulk of current research on teacher professional development is focused on teacher learning in the context of teacher professional learning communities (PLCs). In teacher PLCs, groups of teachers meet regularly to increase their own learning and the learning of their students. Teacher PLCs offer a learning model in which, "new ideas and…
ERIC Educational Resources Information Center
Bias, Timothy A.
2009-01-01
Purpose. The purpose of this study was to reveal differences between Program Improvement (PI) middle school scripted program and nonscripted program teachers' perceptions of their schools as professional learning communities (PLCs). The concept of PLCs is framed by Hord's (1997) 5 attributes of successful PLCs: supportive shared leadership, shared…
ERIC Educational Resources Information Center
Archbald, Doug
2016-01-01
Objective of the Case--There is a large volume of theoretical and "how to" literature on professional learning communities (PLCs), but little documenting the challenges of implementation and even less on the challenges of system-wide implementation of PLCs. This case is about the role of the central office in initiating and supporting…
Generating Safety-Critical PLC Code From a High-Level Application Software Specification
NASA Technical Reports Server (NTRS)
2008-01-01
The benefits of automatic-application code generation are widely accepted within the software engineering community. These benefits include raised abstraction level of application programming, shorter product development time, lower maintenance costs, and increased code quality and consistency. Surprisingly, code generation concepts have not yet found wide acceptance and use in the field of programmable logic controller (PLC) software development. Software engineers at Kennedy Space Center recognized the need for PLC code generation while developing the new ground checkout and launch processing system, called the Launch Control System (LCS). Engineers developed a process and a prototype software tool that automatically translates a high-level representation or specification of application software into ladder logic that executes on a PLC. All the computer hardware in the LCS is planned to be commercial off the shelf (COTS), including industrial controllers or PLCs that are connected to the sensors and end items out in the field. Most of the software in LCS is also planned to be COTS, with only small adapter software modules that must be developed in order to interface between the various COTS software products. A domain-specific language (DSL) is a programming language designed to perform tasks and to solve problems in a particular domain, such as ground processing of launch vehicles. The LCS engineers created a DSL for developing test sequences of ground checkout and launch operations of future launch vehicle and spacecraft elements, and they are developing a tabular specification format that uses the DSL keywords and functions familiar to the ground and flight system users. The tabular specification format, or tabular spec, allows most ground and flight system users to document how the application software is intended to function and requires little or no software programming knowledge or experience. A small sample from a prototype tabular spec application is shown.
ERIC Educational Resources Information Center
Tam, Angela Choi Fung
2015-01-01
Factors leading to successful professional learning communities (PLCs) have been widely discussed in the West, but little is known about how/whether teachers' beliefs contribute to PLCs in the Chinese context. This qualitative case study aimed to investigate teachers' beliefs about teacher learning in PLCs and their influence on collegial learning…
Federal Register 2010, 2011, 2012, 2013, 2014
2012-06-05
... Operations Management Tricon Programmable Logic Controller (PLC), Version 10, and the CS Innovations, LLC... process protection system that is based on the Invensys Operations Management Tricon Programmable Logic...
PLCs used in smart home control
NASA Astrophysics Data System (ADS)
Barz, C.; Deaconu, S. I.; Latinovic, T.; Berdie, A.; Pop-Vadean, A.; Horgos, M.
2016-02-01
This paper presents the realization of a smart home automation using Siemens PLCs. The smart home interface is realized using the HMI Weintek eMT3070a touchscreen, which shows the window for controlling and monitoring the lighting, room temperature, irrigation systems, swimming pool, etc. By using PLCs, the smart home can be controlled via Ethernet and it can be programmed to the needs of tenants.
pH-programmable DNA logic arrays powered by modular DNAzyme libraries.
Elbaz, Johann; Wang, Fuan; Remacle, Francoise; Willner, Itamar
2012-12-12
Nature performs complex information processing circuits, such the programmed transformations of versatile stem cells into targeted functional cells. Man-made molecular circuits are, however, unable to mimic such sophisticated biomachineries. To reach these goals, it is essential to construct programmable modular components that can be triggered by environmental stimuli to perform different logic circuits. We report on the unprecedented design of artificial pH-programmable DNA logic arrays, constructed by modular libraries of Mg(2+)- and UO(2)(2+)-dependent DNAzyme subunits and their substrates. By the appropriate modular design of the DNA computation units, pH-programmable logic arrays of various complexities are realized, and the arrays can be erased, reused, and/or reprogrammed. Such systems may be implemented in the near future for nanomedical applications by pH-controlled regulation of cellular functions or may be used to control biotransformations stimulated by bacteria.
Industrial Control System Process-Oriented Intrusion Detection (iPoid) Algorithm
2016-08-01
inspection rules using an intrusion-detection system (IDS) sensor, a simulated Programmable Logic Controller (PLC), and a Modbus client operating...operating system PLC Programmable Logic Controller SCADA supervisory control and data acquisition SIGHUP signal hangup SPAN Switched Port Analyzer
Programmable Logic Application Notes
NASA Technical Reports Server (NTRS)
Katz, Richard
2000-01-01
This column will be provided each quarter as a source for reliability, radiation results, NASA capabilities, and other information on programmable logic devices and related applications. This quarter will start a series of notes concentrating on analysis techniques with this issues section discussing worst-case analysis requirements.
Optical programmable Boolean logic unit.
Chattopadhyay, Tanay
2011-11-10
Logic units are the building blocks of many important computational operations likes arithmetic, multiplexer-demultiplexer, radix conversion, parity checker cum generator, etc. Multifunctional logic operation is very much essential in this respect. Here a programmable Boolean logic unit is proposed that can perform 16 Boolean logical operations from a single optical input according to the programming input without changing the circuit design. This circuit has two outputs. One output is complementary to the other. Hence no loss of data can occur. The circuit is basically designed by a 2×2 polarization independent optical cross bar switch. Performance of the proposed circuit has been achieved by doing numerical simulations. The binary logical states (0,1) are represented by the absence of light (null) and presence of light, respectively.
Programmable resistive-switch nanowire transistor logic circuits.
Shim, Wooyoung; Yao, Jun; Lieber, Charles M
2014-09-10
Programmable logic arrays (PLA) constitute a promising architecture for developing increasingly complex and functional circuits through nanocomputers from nanoscale building blocks. Here we report a novel one-dimensional PLA element that incorporates resistive switch gate structures on a semiconductor nanowire and show that multiple elements can be integrated to realize functional PLAs. In our PLA element, the gate coupling to the nanowire transistor can be modulated by the memory state of the resistive switch to yield programmable active (transistor) or inactive (resistor) states within a well-defined logic window. Multiple PLA nanowire elements were integrated and programmed to yield a working 2-to-4 demultiplexer with long-term retention. The well-defined, controllable logic window and long-term retention of our new one-dimensional PLA element provide a promising route for building increasingly complex circuits with nanoscale building blocks.
Programmable Logic Application Notes
NASA Technical Reports Server (NTRS)
Katz, Richard; Day, John H. (Technical Monitor)
2001-01-01
This report will be provided each quarter as a source for reliability, radiation results, NASA capabilities, and other information on programmable logic devices and related applications. This quarter will continue a series of notes concentrating on analysis techniques with this issue's section discussing the use of Root-Sum-Square calculations for digital delays.
Introducing Programmable Logic to Undergraduate Engineering Students in a Digital Electronics Course
ERIC Educational Resources Information Center
Todorovich, E.; Marone, J. A.; Vazquez, M.
2012-01-01
Due to significant technological advances and industry requirements, many universities have introduced programmable logic and hardware description languages into undergraduate engineering curricula. This has led to a number of logistical and didactical challenges, in particular for computer science students. In this paper, the integration of some…
Programming Programmable Logic Controller. High-Technology Training Module.
ERIC Educational Resources Information Center
Lipsky, Kevin
This training module on programming programmable logic controllers (PLC) is part of the memory structure and programming unit used in a packaging systems equipment control course. In the course, students assemble, install, maintain, and repair industrial machinery used in industry. The module contains description, objectives, content outline,…
NASA Astrophysics Data System (ADS)
Jones, M. Gail; Gardner, Grant E.; Robertson, Laura; Robert, Sarah
2013-07-01
Professional Learning Communities (PLCs) are frequently being used as a vehicle to transform science education. This study explored elementary teachers' perceptions about the impact of participating in a science PLC on their own professional development. With the use of The Science Professional Learning Communities Survey and a semi-structured interview protocol, elementary teachers' perceptions of the goals of science PLCs, the constraints and benefits of participation in PLCs, and reported differences in the impact of PLC participation on novice and experienced teachers were examined. Sixty-five elementary teachers who participated in a science PLC were surveyed about their experiences, and a subsample of 16 teachers was interviewed. Results showed that most of the teachers reported their science PLC emphasized sharing ideas with other teachers as well as working to improve students' science standardized test scores. Teachers noted that the PLCs had impacted their science assessment practices as well as their lesson planning. However, a majority of the participants reported a differential impact of PLCs depending on a teacher's level of experience. PLCs were reported as being more beneficial to new teachers than experienced teachers. The interview results demonstrated that there were often competing goals and in some cases a loss of autonomy in planning science lessons. A significant concern was the impact of problematic interpersonal relationships and communication styles on the group functioning. The role of the PLC in addressing issues related to obtaining science resources and enhancing science content knowledge for elementary science teachers is discussed.
Professional Learning Communities (PLCs) as a Means for School-Based Science Curriculum Change
NASA Astrophysics Data System (ADS)
Browne, Christi L.
The challenge of school-based science curriculum change and educational reform is often presented to science teachers and departments who are not necessarily prepared for the complexity of considerations that change movements require. The development of a Professional Learning Community (PLC) focused on a science department's curriculum change efforts, may provide the necessary tools to foster sustainable school-based curriculum science changes. This research presents a case study of an evolving science department PLC consisting of 10 middle school science teachers from the same middle school and their efforts of school-based science curriculum change. A transformative mixed model case study with qualitative data and deepened by quantitative analysis, was chosen to guide the investigation. Collected data worked to document the essential developmental steps, the occurrence and frequency of the five essential dimensions of successful PLCs, and the influences the science department PLC had on the middle school science department's progression through school-based science curriculum change, and the barriers, struggles and inhibiting actions of the science department PLC. Findings indicated that a science department PLC was unique in that it allowed for a focal science departmental lens of science curriculum change to be applied to the structure and function of the PLC and therefore the process, proceedings, and results were directly aligned to and driven by the science department. The science PLC, while logically difficult to set-up and maintain, became a professional science forum where the middle school science teachers were exposed to new science teaching and learning knowledge, explored new science standards, discussed effects on student science learning, designed and critically analyzed science curriculum change application. Conclusions resulted in the science department PLC as an identified tool providing the ability for science departmental actions to lead to outcomes of science curriculum change improvements with the consideration but not the dictation of the larger school community and state agendas. Thus, the study's results work to fuse previously separated research on general PLCs and curriculum change efforts into a cohesive understanding of the unexplored potential of a science PLC and school-based science curriculum change.
Programmable Logic Application Notes
NASA Technical Reports Server (NTRS)
Katz, Richard
1998-01-01
This column will be provided each quarter as a source for reliability, radiation results, NASA capabilities, and other information on programmable logic devices and related applications. This quarter's column will include some announcements and some recent radiation test results and evaluations of interest. Specifically, the following topics will be covered: the Military and Aerospace Applications of Programmable Devices and Technologies Conference to be held at GSFC in September, 1998, proton test results, and some total dose results.
NASA Astrophysics Data System (ADS)
Zhang, W. X.; Zhao, S. R.; Sun, C. P.
1997-02-01
A general self-consistent field (SCF) for the mixture of polymer and low molecular weight (LMW) molecules has been derived by variation principle. Considering a Maier-Saupe type of interaction, the analytical expressions of the SCF for polymer liquid crystals (PLCs) and the mixture of PLCs and LMW liquid crystals are obtained, from which the phase behaviors of PLCs as well as the mixture are studied. The theoretical results are in agreement with experimental results by adjusting a parameter.
Universal programmable logic gate and routing method
NASA Technical Reports Server (NTRS)
Vatan, Farrokh (Inventor); Akarvardar, Kerem (Inventor); Mojarradi, Mohammad M. (Inventor); Fijany, Amir (Inventor); Cristoloveanu, Sorin (Inventor); Kolawa, Elzbieta (Inventor); Blalock, Benjamin (Inventor); Chen, Suheng (Inventor); Toomarian, Nikzad (Inventor)
2009-01-01
An universal and programmable logic gate based on G.sup.4-FET technology is disclosed, leading to the design of more efficient logic circuits. A new full adder design based on the G.sup.4-FET is also presented. The G.sup.4-FET can also function as a unique router device offering coplanar crossing of signal paths that are isolated and perpendicular to one another. This has the potential of overcoming major limitations in VLSI design where complex interconnection schemes have become increasingly problematic.
Sign-And-Magnitude Up/Down Counter
NASA Technical Reports Server (NTRS)
Cole, Steven W.
1991-01-01
Magnitude-and-sign counter includes conventional up/down counter for magnitude part and special additional circuitry for sign part. Negative numbers indicated more directly. Counter implemented by programming erasable programmable logic device (EPLD) or programmable logic array (PLA). Used in place of conventional up/down counter to provide sign and magnitude values directly to other circuits.
Programmable nanowire circuits for nanoprocessors.
Yan, Hao; Choe, Hwan Sung; Nam, SungWoo; Hu, Yongjie; Das, Shamik; Klemic, James F; Ellenbogen, James C; Lieber, Charles M
2011-02-10
A nanoprocessor constructed from intrinsically nanometre-scale building blocks is an essential component for controlling memory, nanosensors and other functions proposed for nanosystems assembled from the bottom up. Important steps towards this goal over the past fifteen years include the realization of simple logic gates with individually assembled semiconductor nanowires and carbon nanotubes, but with only 16 devices or fewer and a single function for each circuit. Recently, logic circuits also have been demonstrated that use two or three elements of a one-dimensional memristor array, although such passive devices without gain are difficult to cascade. These circuits fall short of the requirements for a scalable, multifunctional nanoprocessor owing to challenges in materials, assembly and architecture on the nanoscale. Here we describe the design, fabrication and use of programmable and scalable logic tiles for nanoprocessors that surmount these hurdles. The tiles were built from programmable, non-volatile nanowire transistor arrays. Ge/Si core/shell nanowires coupled to designed dielectric shells yielded single-nanowire, non-volatile field-effect transistors (FETs) with uniform, programmable threshold voltages and the capability to drive cascaded elements. We developed an architecture to integrate the programmable nanowire FETs and define a logic tile consisting of two interconnected arrays with 496 functional configurable FET nodes in an area of ∼960 μm(2). The logic tile was programmed and operated first as a full adder with a maximal voltage gain of ten and input-output voltage matching. Then we showed that the same logic tile can be reprogrammed and used to demonstrate full-subtractor, multiplexer, demultiplexer and clocked D-latch functions. These results represent a significant advance in the complexity and functionality of nanoelectronic circuits built from the bottom up with a tiled architecture that could be cascaded to realize fully integrated nanoprocessors with computing, memory and addressing capabilities.
Kneale, Dylan; Thomas, James; Harris, Katherine
2015-01-01
Logic models are becoming an increasingly common feature of systematic reviews, as is the use of programme theory more generally in systematic reviewing. Logic models offer a framework to help reviewers to 'think' conceptually at various points during the review, and can be a useful tool in defining study inclusion and exclusion criteria, guiding the search strategy, identifying relevant outcomes, identifying mediating and moderating factors, and communicating review findings. In this paper we critique the use of logic models in systematic reviews and protocols drawn from two databases representing reviews of health interventions and international development interventions. Programme theory featured only in a minority of the reviews and protocols included. Despite drawing from different disciplinary traditions, reviews and protocols from both sources shared several limitations in their use of logic models and theories of change, and these were used almost unanimously to solely depict pictorially the way in which the intervention worked. Logic models and theories of change were consequently rarely used to communicate the findings of the review. Logic models have the potential to be an aid integral throughout the systematic reviewing process. The absence of good practice around their use and development may be one reason for the apparent limited utility of logic models in many existing systematic reviews. These concerns are addressed in the second half of this paper, where we offer a set of principles in the use of logic models and an example of how we constructed a logic model for a review of school-based asthma interventions.
Improving excellence in scoliosis rehabilitation: a controlled study of matched pairs.
Weiss, H-R; Klein, R
2006-01-01
Physiotherapy programmes so far mainly address the lateral deformity of scoliosis, a few aim at the correction of rotation and only very few address the sagittal profile. Meanwhile, there is evidence that correction forces applied in the sagittal plane are also able to correct the scoliotic deformity in the coronal and frontal planes. So it should be possible to improve excellence in scoliosis rehabilitation by the implementation of exercises to correct the sagittal deformity in scoliosis patients. An exercise programme (physio-logic exercises) aiming at a physiologic sagittal profile was developed to add to the programme applied at the centre or to replace certain exercises or exercising positions. To test the hypothesis that physio-logic exercises improve the outcome of Scoliosis Intensive Rehabilitation (SIR), the following study design was chosen: Prospective controlled trial of pairs of patients with idiopathic scoliosis matched by sex, age, Cobb angle and curve pattern. There were 18 patients in the treatment group (SIR + physio-logic exercises) and 18 patients in the control group (SIR only), all in matched pairs. Average Cobb angle in the treatment group was 34.5 degrees (SD 7.8) Cobb angle in the control group was 31.6 degrees (SD 5.8). Age in the treatment group was at average 15.3 years (SD 1.1) and in the control group 14.7 years (SD 1.3). Thirteen of the 18 patients in either group had a brace. Outcome parameter: average lateral deviation (mm), average surface rotation ( degrees ) and maximum Kyphosis angle ( degrees ) as evaluated with the help of surface topography (Formetric-system). Lateral deviation (mm) decreased significantly after the performance of the physio-logic programme and highly significantly in the physio-logic ADL posture; however, it was not significant after completion of the whole rehabilitation programme (2.3 vs 0.3 mm in the controls). Surface rotation improved at average 1.2 degrees in the treatment group and 0.8 degrees in the controls while Kyphosis angle did not improve in both groups. The physio-logic programme has to be regarded as a useful 'add on' to Scoliosis Rehabilitation with regards to the lateral deviation of the scoliotic trunk. A longitudinal controlled study is necessary to evaluate the long-term effect of the the physio-logic programme also with the help of X-rays.
The role of microtubules in contractile ring function.
Conrad, A H; Paulsen, A Q; Conrad, G W
1992-05-01
During cytokinesis, a cortical contractile ring forms around a cell, constricts to a stable tight neck and terminates in separation of the daughter cells. At first cleavage, Ilyanassa obsoleta embryos form two contractile rings simultaneously. The cleavage furrow (CF), in the animal hemisphere between the spindle poles, constricts to a stable tight neck and separates the daughter cells. The third polar lobe constriction (PLC-3), in the vegetal hemisphere below the spindle, constricts to a transient tight neck, but then relaxes, allowing the polar lobe cytoplasm to merge with one daughter cell. Eggs exposed to taxol, a drug that stabilizes microtubules, before the CF or the PLC-3 develop, fail to form CFs, but form stabilized tight PLCs. Eggs exposed to taxol at the time of PLC-3 formation develop varied numbers of constriction rings in their animal hemispheres and one PLC in their vegetal hemisphere, none of which relax. Eggs exposed to taxol after PLC-3 initiation form stabilized tight CFs and PLCs. At maximum constriction, control embryos display immunolocalization of nonextractable alpha-tubulin in their CFs, but not in their PLCs, and reveal, via electron microscopy, many microtubules extending through their CFs, but not through their PLCs. Embryos which form stabilized tightly constricted CFs and PLCs in the presence of taxol display immunolocalization of nonextractable alpha-tubulin in both constrictions and show many polymerized microtubules extending through both CFs and PLCs. These results suggest that the extension of microtubules through a tight contractile ring may be important for stabilizing that constriction and facilitating subsequent cytokinesis.
The role of microtubules in contractile ring function
NASA Technical Reports Server (NTRS)
Conrad, A. H.; Paulsen, A. Q.; Conrad, G. W.; Spooner, B. S. (Principal Investigator)
1992-01-01
During cytokinesis, a cortical contractile ring forms around a cell, constricts to a stable tight neck and terminates in separation of the daughter cells. At first cleavage, Ilyanassa obsoleta embryos form two contractile rings simultaneously. The cleavage furrow (CF), in the animal hemisphere between the spindle poles, constricts to a stable tight neck and separates the daughter cells. The third polar lobe constriction (PLC-3), in the vegetal hemisphere below the spindle, constricts to a transient tight neck, but then relaxes, allowing the polar lobe cytoplasm to merge with one daughter cell. Eggs exposed to taxol, a drug that stabilizes microtubules, before the CF or the PLC-3 develop, fail to form CFs, but form stabilized tight PLCs. Eggs exposed to taxol at the time of PLC-3 formation develop varied numbers of constriction rings in their animal hemispheres and one PLC in their vegetal hemisphere, none of which relax. Eggs exposed to taxol after PLC-3 initiation form stabilized tight CFs and PLCs. At maximum constriction, control embryos display immunolocalization of nonextractable alpha-tubulin in their CFs, but not in their PLCs, and reveal, via electron microscopy, many microtubules extending through their CFs, but not through their PLCs. Embryos which form stabilized tightly constricted CFs and PLCs in the presence of taxol display immunolocalization of nonextractable alpha-tubulin in both constrictions and show many polymerized microtubules extending through both CFs and PLCs. These results suggest that the extension of microtubules through a tight contractile ring may be important for stabilizing that constriction and facilitating subsequent cytokinesis.
2016-05-01
A9 CPU and 15 W for the i7 CPU. A method of accelerating this computation is by using a customized hardware unit called a field- programmable gate...implementation of custom logic to accelerate com- putational workloads. This FPGA fabric, in addition to the standard programmable logic, contains 220...chip; field- programmable gate array Daniel Gebhardt U U U U 18 (619) 553-2786 INITIAL DISTRIBUTION 84300 Library (2) 85300 Archive/Stock (1
2016-05-01
A9 CPU and 15 W for the i7 CPU. A method of accelerating this computation is by using a customized hardware unit called a field- programmable gate...implementation of custom logic to accelerate com- putational workloads. This FPGA fabric, in addition to the standard programmable logic, contains 220...chip; field- programmable gate array Daniel Gebhardt U U U U 18 (619) 553-2786 INITIAL DISTRIBUTION 84300 Library (2) 85300 Archive/Stock (1
A Project-Based Learning Approach to Programmable Logic Design and Computer Architecture
ERIC Educational Resources Information Center
Kellett, C. M.
2012-01-01
This paper describes a course in programmable logic design and computer architecture as it is taught at the University of Newcastle, Australia. The course is designed around a major design project and has two supplemental assessment tasks that are also described. The context of the Computer Engineering degree program within which the course is…
"Modeling" Youth Work: Logic Models, Neoliberalism, and Community Praxis
ERIC Educational Resources Information Center
Carpenter, Sara
2016-01-01
This paper examines the use of logic models in the development of community initiatives within the AmeriCorps program. AmeriCorps is the civilian national service programme in the U.S., operating as a grants programme to local governments and not-for-profit organisations and providing low-cost labour to address pressing issues of social…
NASA Astrophysics Data System (ADS)
Nakamura, Kazuyuki; Sasao, Tsutomu; Matsuura, Munehiro; Tanaka, Katsumasa; Yoshizumi, Kenichi; Nakahara, Hiroki; Iguchi, Yukihiro
2006-04-01
A large-scale memory-technology-based programmable logic device (PLD) using a look-up table (LUT) cascade is developed in the 0.35-μm standard complementary metal oxide semiconductor (CMOS) logic process. Eight 64 K-bit synchronous SRAMs are connected to form an LUT cascade with a few additional circuits. The features of the LUT cascade include: 1) a flexible cascade connection structure, 2) multi phase pseudo asynchronous operations with synchronous static random access memory (SRAM) cores, and 3) LUT-bypass redundancy. This chip operates at 33 MHz in 8-LUT cascades at 122 mW. Benchmark results show that it achieves a comparable performance to field programmable gate array (FPGAs).
Programmable Logic Application Notes
NASA Technical Reports Server (NTRS)
Katz, Richard
2000-01-01
This column will be provided each quarter as a source for reliability, radiation results, NASA capabilities, and other information on programmable logic devices and related applications. This quarter will continue a series of notes concentrating on analysis techniques with this issue's section discussing: Digital Timing Analysis Tools and Techniques. Articles in this issue include: SX and SX-A Series Devices Power Sequencing; JTAG and SXISX-AISX-S Series Devices; Analysis Techniques (i.e., notes on digital timing analysis tools and techniques); Status of the Radiation Hard reconfigurable Field Programmable Gate Array Program, Input Transition Times; Apollo Guidance Computer Logic Study; RT54SX32S Prototype Data Sets; A54SX32A - 0.22 micron/UMC Test Results; Ramtron FM1608 FRAM; and Analysis of VHDL Code and Synthesizer Output.
Integrated all-optical programmable logic array based on semiconductor optical amplifiers.
Dong, Wenchan; Huang, Zhuyang; Hou, Jie; Santos, Rui; Zhang, Xinliang
2018-05-01
The all-optical programmable logic array (PLA) is one of the most important optical complex logic devices that can implement combinational logic functions. In this Letter, we propose and experimentally demonstrate an integrated all-optical PLA at the operation speed of 40 Gb/s. The PLA mainly consists of a delay interferometer (DI) and semiconductor optical amplifiers (SOAs) of different lengths. The DI is used to pre-code the input signals and improve the reconfigurability of the scheme. The longer SOAs are nonlinear media for generating canonical logic units (CLUs) using four-wave mixing. The shorter SOAs are used to select the appropriate CLUs by changing the working states; then reconfigurable logic functions can be output directly. The results show that all the CLUs are realized successfully, and the optical signal-to-noise ratios are above 22 dB. The exclusive NOR gate and exclusive OR gate are experimentally demonstrated based on output CLUs.
Logic operations based on magnetic-vortex-state networks.
Jung, Hyunsung; Choi, Youn-Seok; Lee, Ki-Suk; Han, Dong-Soo; Yu, Young-Sang; Im, Mi-Young; Fischer, Peter; Kim, Sang-Koog
2012-05-22
Logic operations based on coupled magnetic vortices were experimentally demonstrated. We utilized a simple chain structure consisting of three physically separated but dipolar-coupled vortex-state Permalloy disks as well as two electrodes for application of the logical inputs. We directly monitored the vortex gyrations in the middle disk, as the logical output, by time-resolved full-field soft X-ray microscopy measurements. By manipulating the relative polarization configurations of both end disks, two different logic operations are programmable: the XOR operation for the parallel polarization and the OR operation for the antiparallel polarization. This work paves the way for new-type programmable logic gates based on the coupled vortex-gyration dynamics achievable in vortex-state networks. The advantages are as follows: a low-power input signal by means of resonant vortex excitation, low-energy dissipation during signal transportation by selection of low-damping materials, and a simple patterned-array structure.
Effective Strategies for Sustaining Professional Learning Communities
ERIC Educational Resources Information Center
Bennett, Patricia R.
2010-01-01
Professional Learning Communities (PLCs), in which educators work collaboratively to improve learning for students, need effective strategies to sustain them. PLCs promote continuous improvement in student learning and build academic success with increased teacher expertise. Grounded in organizational systems theory, participative leadership…
EEE Links, Volume 9, No. 1, January 2003 Focus on Plastic Parts
NASA Technical Reports Server (NTRS)
2003-01-01
The January 2003 issue of Electronic, Electromechanical, Electric (EEE) Links is presented. The Programmable Logic Application Notes column has been reinstated in this newsletter. Written by Rich Katz of NASA's Office of Logic Design (OLD), the application notes offer technical tips intended to prevent flight design errors and enhance research, development, and use of programmable logic and elements for space flight applications. An archive of these notes columns from previous issues of EEE Links is available at http://www.klabs.org/richcontent/eeelink s/EEE Links.htm.
De-Regil, Luz Maria; Peña-Rosas, Juan Pablo; Flores-Ayala, Rafael; del Socorro Jefferds, Maria Elena
2015-01-01
Objective Nutrition interventions are critical to achieve the Millennium Development Goals; among them, micronutrient interventions are considered cost-effective and programmatically feasible to scale up, but there are limited tools to communicate the programme components and their relationships. The WHO/CDC (Centers for Disease Control and Prevention) logic model for micronutrient interventions in public health programmes is a useful resource for planning, implementation, monitoring and evaluation of these interventions, which depicts the programme theory and expected relationships between inputs and expected Millennium Development Goals. Design The model was developed by applying principles of programme evaluation, public health nutrition theory and programmatic expertise. The multifaceted and iterative structure validation included feedback from potential users and adaptation by national stakeholders involved in public health programmes' design and implementation. Results In addition to the inputs, main activity domains identified as essential for programme development, implementation and performance include: (i) policy; (ii) products and supply; (iii) delivery systems; (iv) quality control; and (v) behaviour change communication. Outputs encompass the access to and coverage of interventions. Outcomes include knowledge and appropriate use of the intervention, as well as effects on micronutrient intake, nutritional status and health of target populations, for ultimate achievement of the Millennium Development Goals. Conclusions The WHO/CDC logic model simplifies the process of developing a logic model by providing a tool that has identified high-priority areas and concepts that apply to virtually all public health micronutrient interventions. Countries can adapt it to their context in order to support programme design, implementation, monitoring and evaluation for the successful scale-up of nutrition interventions in public health. PMID:23507463
Kneale, Dylan; Thomas, James; Harris, Katherine
2015-01-01
Background Logic models are becoming an increasingly common feature of systematic reviews, as is the use of programme theory more generally in systematic reviewing. Logic models offer a framework to help reviewers to ‘think’ conceptually at various points during the review, and can be a useful tool in defining study inclusion and exclusion criteria, guiding the search strategy, identifying relevant outcomes, identifying mediating and moderating factors, and communicating review findings. Methods and Findings In this paper we critique the use of logic models in systematic reviews and protocols drawn from two databases representing reviews of health interventions and international development interventions. Programme theory featured only in a minority of the reviews and protocols included. Despite drawing from different disciplinary traditions, reviews and protocols from both sources shared several limitations in their use of logic models and theories of change, and these were used almost unanimously to solely depict pictorially the way in which the intervention worked. Logic models and theories of change were consequently rarely used to communicate the findings of the review. Conclusions Logic models have the potential to be an aid integral throughout the systematic reviewing process. The absence of good practice around their use and development may be one reason for the apparent limited utility of logic models in many existing systematic reviews. These concerns are addressed in the second half of this paper, where we offer a set of principles in the use of logic models and an example of how we constructed a logic model for a review of school-based asthma interventions. PMID:26575182
Efficient Multiplexer FPGA Block Structures Based on G4FETs
NASA Technical Reports Server (NTRS)
Vatan, Farrokh; Fijany, Amir
2009-01-01
Generic structures have been conceived for multiplexer blocks to be implemented in field-programmable gate arrays (FPGAs) based on four-gate field-effect transistors (G(sup 4)FETs). This concept is a contribution to the continuing development of digital logic circuits based on G4FETs and serves as a further demonstration that logic circuits based on G(sup 4)FETs could be more efficient (in the sense that they could contain fewer transistors), relative to functionally equivalent logic circuits based on conventional transistors. Results in this line of development at earlier stages were summarized in two previous NASA Tech Briefs articles: "G(sup 4)FETs as Universal and Programmable Logic Gates" (NPO-41698), Vol. 31, No. 7 (July 2007), page 44, and "Efficient G4FET-Based Logic Circuits" (NPO-44407), Vol. 32, No. 1 ( January 2008), page 38 . As described in the first-mentioned previous article, a G4FET can be made to function as a three-input NOT-majority gate, which has been shown to be a universal and programmable logic gate. The universality and programmability could be exploited to design logic circuits containing fewer components than are required for conventional transistor-based circuits performing the same logic functions. The second-mentioned previous article reported results of a comparative study of NOT-majority-gate (G(sup 4)FET)-based logic-circuit designs and equivalent NOR- and NAND-gate-based designs utilizing conventional transistors. [NOT gates (inverters) were also included, as needed, in both the G(sup 4)FET- and the NOR- and NAND-based designs.] In most of the cases studied, fewer logic gates (and, hence, fewer transistors), were required in the G(sup 4)FET-based designs. There are two popular categories of FPGA block structures or architectures: one based on multiplexers, the other based on lookup tables. In standard multiplexer- based architectures, the basic building block is a tree-like configuration of multiplexers, with possibly a few additional logic gates such as ANDs or ORs. Interconnections are realized by means of programmable switches that may connect the input terminals of a block to output terminals of other blocks, may bridge together some of the inputs, or may connect some of the input terminals to signal sources representing constant logical levels 0 or 1. The left part of the figure depicts a four-to-one G(sup 4)FET-based multiplexer tree; the right part of the figure depicts a functionally equivalent four-to-one multiplexer based on conventional transistors. The G(sup 4)FET version would contains 54 transistors; the conventional version contains 70 transistors.
FPGA implementation of bit controller in double-tick architecture
NASA Astrophysics Data System (ADS)
Kobylecki, Michał; Kania, Dariusz
2017-11-01
This paper presents a comparison of the two original architectures of programmable bit controllers built on FPGAs. Programmable Logic Controllers (which include, among other things programmable bit controllers) built on FPGAs provide a efficient alternative to the controllers based on microprocessors which are expensive and often too slow. The presented and compared methods allow for the efficient implementation of any bit control algorithm written in Ladder Diagram language into the programmable logic system in accordance with IEC61131-3. In both cases, we have compared the effect of the applied architecture on the performance of executing the same bit control program in relation to its own size.
Versatile logic devices based on programmable DNA-regulated silver-nanocluster signal transducers.
Huang, Zhenzhen; Tao, Yu; Pu, Fang; Ren, Jinsong; Qu, Xiaogang
2012-05-21
A DNA-encoding strategy is reported for the programmable regulation of the fluorescence properties of silver nanoclusters (AgNCs). By taking advantage of the DNA-encoding strategy, aqueous AgNCs were used as signal transducers to convert DNA inputs into fluorescence outputs for the construction of various DNA-based logic gates (AND, OR, INHIBIT, XOR, NOR, XNOR, NAND, and a sequential logic gate). Moreover, a biomolecular keypad that was capable of constructing crossword puzzles was also fabricated. These AgNC-based logic systems showed several advantages, including a simple transducer-introduction strategy, universal design, and biocompatible operation. In addition, this proof of concept opens the door to a new generation of signal transducer materials and provides a general route to versatile biomolecular logic devices for practical applications. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Simões, M G; Alves, P; Carvalheiro, Manuela; Simões, P N
2017-04-01
The development of polymer-liposome complexes (PLCs), in particular for biomedical applications, has grown significantly in the last decades. The importance of these studies comes from the emerging need in finding intelligent controlled release systems, more predictable, effective and selective, for applications in several areas, such as treatment and/or diagnosis of cancer, neurological, dermatological, ophthalmic and orthopedic diseases, gene therapy, cosmetic treatments, and food engineering. This work reports the development and characterization of a pH sensitive system for controlled release based on PLCs. The selected hydrophilic polymer was poly(acrylic acid) (PAA) synthesized by atom transfer radical polymerization (ATRP) with a cholesterol (CHO) end-group to improve the anchoring of the polymer into the lipid bilayer. The polymer was incorporated into liposomes formulated from soybean lecithin and stearylamine, with different stearylamine/phospholipid and polymer/phospholipid ratios (5, 10 and 20%). The developed PLCs were characterized in terms of particle size, polydispersity, zeta potential, release profiles, and encapsulation efficiency. Cell viability studies were performed to assess the cytotoxic potential of PLCs. The results showed that the liposomal formulation with 5% of stearylamine and 10% of polymer positively contribute to the stabilization of the complexes. Afterwards, the carboxylic acid groups of the polymer present at the surface of the liposomes were crosslinked and the same parameters analyzed. The crosslinked complexes showed to be more stable at physiologic conditions. In addition, the release profiles at different pHs (2-12) revealed that the obtained complexes released all their content at acidic conditions. In summary, the main accomplishments of this work are: (i) innovative synthesis of cholesterol-poly(acrylic acid) (CHO-PAA) by ATRP; (ii) stabilization of the liposomal formulation by incorporation of stearylamine and CHO-PAA; (iii) new approach for CHO-PAA crosslinking, resulting in more stable PLCs at physiological conditions; (iv) destabilization of PLCs upon slight changes of pH, showing their pH sensitivity; and (v) the PLCs do not exhibit cellular toxicity. Copyright © 2017 Elsevier B.V. All rights reserved.
ERIC Educational Resources Information Center
Hirsh, Stephanie; Hord, Shirley M.
2008-01-01
One of the most powerful ways for principals to extend their learning is to participate in professional learning communities (PLCs), forums that are explicitly designed to convene educators for learning so that students perform at higher levels. Principals can use PLCs to their professional advantage in two significant ways: (1) by participating…
Situating Teacher Inquiry: A Micropolitical Perspective
ERIC Educational Resources Information Center
LeChasseur, Kimberly; Mayer, Anysia; Welton, Anjale; Donaldson, Morgaen
2016-01-01
Professional learning communities (PLCs) have become a popular strategy in various forms (e.g., data teams, grade-level teams) and with various champions (e.g., district leaders, university researchers, teacher advocates). Although well-implemented PLCs have been shown to distribute leadership, the tension between democratic inquiry processes and…
Programmable logic construction kits for hyper-real-time neuronal modeling.
Guerrero-Rivera, Ruben; Morrison, Abigail; Diesmann, Markus; Pearce, Tim C
2006-11-01
Programmable logic designs are presented that achieve exact integration of leaky integrate-and-fire soma and dynamical synapse neuronal models and incorporate spike-time dependent plasticity and axonal delays. Highly accurate numerical performance has been achieved by modifying simpler forward-Euler-based circuitry requiring minimal circuit allocation, which, as we show, behaves equivalently to exact integration. These designs have been implemented and simulated at the behavioral and physical device levels, demonstrating close agreement with both numerical and analytical results. By exploiting finely grained parallelism and single clock cycle numerical iteration, these designs achieve simulation speeds at least five orders of magnitude faster than the nervous system, termed here hyper-real-time operation, when deployed on commercially available field-programmable gate array (FPGA) devices. Taken together, our designs form a programmable logic construction kit of commonly used neuronal model elements that supports the building of large and complex architectures of spiking neuron networks for real-time neuromorphic implementation, neurophysiological interfacing, or efficient parameter space investigations.
The Role of Departmental Leadership for Professional Learning Communities
ERIC Educational Resources Information Center
Vanblaere, Bénédicte; Devos, Geert
2018-01-01
Purpose: Department heads play a pivotal role in the functioning of departments in secondary schools. However, quantitative research about the role of departmental leadership for the development of professional learning communities (PLCs) in subject departments in secondary schools remains scarce. As PLCs are seen as promising contexts for…
Stay Connected: Using Technology to Enhance Professional Learning Communities
ERIC Educational Resources Information Center
Bates, Celeste C.; Huber, Rachael; McClure, Erin
2016-01-01
Professional Learning Communities (PLCs) offer opportunities for educators to collaboratively inquire and study innovative literacy practices. However, scheduling conflicts and other challenges often interrupt or create barriers for PLCs. This article provides suggestions for integrating technology into a face-to-face PLC as a means of supporting…
Science-for-Teaching Discourse in Science Teachers' Professional Learning Communities
ERIC Educational Resources Information Center
Lohwasser, Karin
2013-01-01
Professional learning communities (PLCs) provide an increasingly common structure for teachers' professional development. The effectiveness of PLCs depends on the content and quality of the participants' discourse. This dissertation was conducted to add to an understanding of the science content needed to prepare to teach science, and the…
ERIC Educational Resources Information Center
Caldarella, Paul; Hallam, Pamela R.; Christensen, Lynnette; Wall, Gary
2014-01-01
Professional learning communities (PLCs) are an increasingly popular strategy for improving schools. While PLCs routinely implement universal academic screening, they seldom screen for emotional and behavioral problems. This is unfortunate, as the early signs of emotional and behavioral disorders can be identified and interventions developed. The…
Elementary Teachers' Perceptions of Professional Learning Communities
ERIC Educational Resources Information Center
Gamez, Octavio
2012-01-01
This study presents the results of a social constructivist mixed methods investigation into the perceptions and experiences of elementary teachers participating in professional learning communities (PLCs). In order to better understand the dynamics involved in PLCs, this research used a team development model from human resources literature. Of…
Socialization and Language for Students with Hearing Impairments.
ERIC Educational Resources Information Center
Beattie, Rod G.
1998-01-01
Addresses the importance of teaching students with hearing impairments zero-order pragmatic-language competencies (PLCs), those communicative and interactive behaviors necessary in everyday social situations to avoid being seen as deviant. Among PLCs are taking turns, initiating or adding to a conversation, and making repairs when necessary. Many…
PLCs, DI, & RTI: A Tapestry for School Change
ERIC Educational Resources Information Center
Stoehr, Judy; Banks, Maria; Allen, Linda
2011-01-01
Rather than buying individual books about professional learning communities (PLCs), differentiated instruction (DI), and Response to Intervention (RTI), invest wisely in one resource that synthesizes all three. The text uses a tapestry analogy to weave together these critical topics to form a comprehensive framework for achieving continuous school…
Compact universal logic gates realized using quantization of current in nanodevices.
Zhang, Wancheng; Wu, Nan-Jian; Yang, Fuhua
2007-12-12
This paper proposes novel universal logic gates using the current quantization characteristics of nanodevices. In nanodevices like the electron waveguide (EW) and single-electron (SE) turnstile, the channel current is a staircase quantized function of its control voltage. We use this unique characteristic to compactly realize Boolean functions. First we present the concept of the periodic-threshold threshold logic gate (PTTG), and we build a compact PTTG using EW and SE turnstiles. We show that an arbitrary three-input Boolean function can be realized with a single PTTG, and an arbitrary four-input Boolean function can be realized by using two PTTGs. We then use one PTTG to build a universal programmable two-input logic gate which can be used to realize all two-input Boolean functions. We also build a programmable three-input logic gate by using one PTTG. Compared with linear threshold logic gates, with the PTTG one can build digital circuits more compactly. The proposed PTTGs are promising for future smart nanoscale digital system use.
Field-programmable logic devices with optical input-output.
Szymanski, T H; Saint-Laurent, M; Tyan, V; Au, A; Supmonchai, B
2000-02-10
A field-programmable logic device (FPLD) with optical I/O is described. FPLD's with optical I/O can have their functionality specified in the field by means of downloading a control-bit stream and can be used in a wide range of applications, such as optical signal processing, optical image processing, and optical interconnects. Our device implements six state-of-the-art dynamically programmable logic arrays (PLA's) on a 2 mm x 2 mm die. The devices were fabricated through the Lucent Technologies-Advanced Research Projects Agency-Consortium for Optical and Optoelectronic Technologies in Computing (Lucent/ARPA/COOP) workshop by use of 0.5-microm complementary metal-oxide semiconductor-self-electro-optic device technology and were delivered in 1998. All devices are fully functional: The electronic data paths have been verified at 200 MHz, and optical tests are pending. The device has been programmed to implement a two-stage optical switching network with six 4 x 4 crossbar switches, which can realize more than 190 x 10(6) unique programmable input-output permutations. The same device scaled to a 2 cm x 2 cm substrate could support as many as 4000 optical I/O and 1 Tbit/s of optical I/O bandwidth and offer fully programmable digital functionality with approximately 110,000 programmable logic gates. The proposed optoelectronic FPLD is also ideally suited to realizing dense, statically reconfigurable crossbar switches. We describe an attractive application area for such devices: a rearrangeable three-stage optical switch for a wide-area-network backbone, switching 1000 traffic streams at the OC-48 data rate and supporting several terabits of traffic.
Expanded all-optical programmable logic array based on multi-input/output canonical logic units.
Lei, Lei; Dong, Jianji; Zou, Bingrong; Wu, Zhao; Dong, Wenchan; Zhang, Xinliang
2014-04-21
We present an expanded all-optical programmable logic array (O-PLA) using multi-input and multi-output canonical logic units (CLUs) generation. Based on four-wave mixing (FWM) in highly nonlinear fiber (HNLF), two-input and three-input CLUs are simultaneously achieved in five different channels with an operation speed of 40 Gb/s. Clear temporal waveforms and wide open eye diagrams are successfully observed. The effectiveness of the scheme is validated by extinction ratio and optical signal-to-noise ratio measurements. The computing capacity, defined as the total amount of logic functions achieved by the O-PLA, is discussed in detail. For a three-input O-PLA, the computing capacity of the expanded CLUs-PLA is more than two times as large as that of the standard CLUs-PLA, and this multiple will increase to more than three and a half as the idlers are individually independent.
Field programmable gate arrays: Evaluation report for space-flight application
NASA Technical Reports Server (NTRS)
Sandoe, Mike; Davarpanah, Mike; Soliman, Kamal; Suszko, Steven; Mackey, Susan
1992-01-01
Field Programmable Gate Arrays commonly called FPGA's are the newer generation of field programmable devices and offer more flexibility in the logic modules they incorporate and in how they are interconnected. The flexibility, the number of logic building blocks available, and the high gate densities achievable are why users find FPGA's attractive. These attributes are important in reducing product development costs and shortening the development cycle. The aerospace community is interested in incorporating this new generation of field programmable technology in space applications. To this end, a consortium was formed to evaluate the quality, reliability, and radiation performance of FPGA's. This report presents the test results on FPGA parts provided by ACTEL Corporation.
DOT National Transportation Integrated Search
2000-02-01
A Fuzzy Logic Ramp Metering Algorithm was implemented on 126 ramps in the greater Seattle area. This report documents the implementation of the Fuzzy Logic Ramp Metering Algorithm at the Northwest District of the Washington State Department of Transp...
Elements Affecting the Development of Professional Learning Communities in Schools
ERIC Educational Resources Information Center
Schaap, Harmen; de Bruijn, Elly
2018-01-01
This article focuses on the development of professional learning communities (PLCs), which are communities within schools, composed of voluntary participating teachers facilitated by school principals with a specific task to accomplish as part of a larger innovation project. Four PLCs were observed during 3 years by using questionnaires and…
ERIC Educational Resources Information Center
Hairon, Salleh; Goh, Jonathan Wee Pin; Chua, Catherine Siew Kheng
2015-01-01
Professional learning communities (PLCs) have gained considerable attention in education. However, PLCs are dependent on how group members collectively work and learn towards shared goals on improving teaching and learning. This would require leadership to support meaningful and productive interactions within PLC contexts, and hence, the…
Light Touch, Heavy Hand: Principals and Data-Use PLCs
ERIC Educational Resources Information Center
Huguet, Alice; Farrell, Caitlin C.; Marsh, Julie A.
2017-01-01
Purpose: The use of data for instructional improvement is prevalent in today's educational landscape, yet policies calling for data use may result in significant variation at the school level. The purpose of this paper is to focus on tools and routines as mechanisms of principal influence on data-use professional learning communities (PLCs).…
ERIC Educational Resources Information Center
Song, Kyoung-Oh; Choi, Jinyoung
2017-01-01
Professional Learning Communities (PLCs) are an important strategy for innovation in schools, and they are receiving considerable attention from scholars and educators alike. The present study aimed to examine the effect of PLCs on schools' effectiveness and to investigate the social, organizational, and structural factors that can promote these…
A Qualitative Exploration of the Perceptions of a Special Education Professional Learning Community
ERIC Educational Resources Information Center
Katz, Marc
2013-01-01
Professional learning communities (PLCs) have been used as a format for encouraging formal collaboration among teachers. The topic of the completed study is the perceptions of special education teachers regarding how special education PLCs meet formal collaboration needs, particularly in terms of isolation. The problem is that special education…
A Qualitative Study of Teachers' Work in Professional Learning Communities in a Small Urban District
ERIC Educational Resources Information Center
Thessin, Rebecca Ann
2010-01-01
Numerous districts are implementing Professional Learning Communities (PLCs) as a part of reform efforts to improve student achievement to meet external accountability mandates. Few districts, however, have considered the essential supports and components that teachers working in PLCs require for these teams to result in instructional improvement.…
Professional Learning Communities and Their Impact on Student Achievement
ERIC Educational Resources Information Center
Story, Zenobia N.
2012-01-01
The purpose of the study was to assess the impact that professional learning communities (PLCs) have on student achievement. Through this study, the statewide performance results of a school district that implemented PLCs were examined. This study of an Illinois school district's statewide assessment results served as a foundation for further…
ERIC Educational Resources Information Center
Somprach, Kanokorn; Tang, Keow Ngang; Popoonsak, Pongtorn
2017-01-01
This study aimed to explore the role of essential leadership styles of school principals in encouraging teachers' participation in professional learning communities (PLCs) in basic education schools in northeastern Thailand. It aimed to identify the nine leadership styles practiced by school principals and teachers' participation in PLCs, and to…
Evaluating PK-12 Professional Learning Communities: An Improvement Science Perspective
ERIC Educational Resources Information Center
Woodland, Rebecca H.
2016-01-01
Professional learning communities (PLCs) have emerged as one of the nation's most widely implemented strategies for improving instruction and PK-12 student learning outcomes. PLCs are predicated on the principles of improvement science, a type of evidenced-based collective inquiry that aims to bridge the research-practice divide and increase…
ERIC Educational Resources Information Center
French, N. Shalene
2013-01-01
Professional Learning Communities (PLCs) provide the basis for meeting the challenges and expectations in today's educational environment. Effective PLCs provide the framework for school improvement and ultimately impact student academic success. School leadership is fundamental in this process (Bennis, 2009; Buffum, Mattos, & Weber, 2009;…
ERIC Educational Resources Information Center
Wang, Ting
2015-01-01
Drawing on data from a larger study on Professional Learning Communities (PLCs) and School Leadership in China, this article investigates the practices of teacher collaboration and PLCs in two urban, high-performing secondary schools in Northeast China. Qualitative data were collected from observations, documents and in-depth semi-structured…
Teachers' Perceptions of Professional Learning Communities and Their Impact on School Culture
ERIC Educational Resources Information Center
Kociuruba, Jerry P., Jr.
2017-01-01
Professional learning communities (PLCs) are a group of educators working collaboratively to improve student achievement and expand the pedagogy of the individual as well as the group. Studies on PLCs, grounded by the social constructivism theory of Vygotsky, Bandura, and Wenger, have found that collaboration and collegiality foster a positive…
ERIC Educational Resources Information Center
Hamos, James E.; Bergin, Kathleen B.; Maki, Daniel P.; Perez, Lance C.; Prival, Joan T.; Rainey, Daphne Y.; Rowell, Ginger H.; VanderPutten, Elizabeth
2009-01-01
This article looks at how professional learning communities (PLCs) have become an operational approach for professional development with potential to de-isolate the teaching experience in the fields of science, technology, engineering, and mathematics (STEM). The authors offer a short synopsis of the intellectual origins of PLCs, provide multiple…
ERIC Educational Resources Information Center
Taylor, Matthew J.; Hallam, Pamela R.; Charlton, Cade T.; Wall, D. Gary
2014-01-01
Professional Learning Communities (PLCs) have become increasingly popular in schools. PLCs are groups of teachers, administrators, parents, and students who collaborate to improve their practices and focus on results (DuFour, 2004). Grade-level and department teachers participate in regularly scheduled collaborative team meetings; however, many…
NASA Technical Reports Server (NTRS)
Baumann, Eric; Merolla, Anthony
1988-01-01
User controls number of clock pulses to prevent burnout. New digital programmable pulser circuit in three formats; freely running, counted, and single pulse. Operates at frequencies up to 5 MHz, with no special consideration given to layout of components or to terminations. Pulser based on sequential circuit with four states and binary counter with appropriate decoding logic. Number of programmable pulses increased beyond 127 by addition of another counter and decoding logic. For very large pulse counts and/or very high frequencies, use synchronous counters to avoid errors caused by propagation delays. Invaluable tool for initial verification or diagnosis of digital or digitally controlled circuity.
Programmable bioelectronics in a stimuli-encoded 3D graphene interface
NASA Astrophysics Data System (ADS)
Parlak, Onur; Beyazit, Selim; Tse-Sum-Bui, Bernadette; Haupt, Karsten; Turner, Anthony P. F.; Tiwari, Ashutosh
2016-05-01
The ability to program and mimic the dynamic microenvironment of living organisms is a crucial step towards the engineering of advanced bioelectronics. Here, we report for the first time a design for programmable bioelectronics, with `built-in' switchable and tunable bio-catalytic performance that responds simultaneously to appropriate stimuli. The designed bio-electrodes comprise light and temperature responsive compartments, which allow the building of Boolean logic gates (i.e. ``OR'' and ``AND'') based on enzymatic communications to deliver logic operations.The ability to program and mimic the dynamic microenvironment of living organisms is a crucial step towards the engineering of advanced bioelectronics. Here, we report for the first time a design for programmable bioelectronics, with `built-in' switchable and tunable bio-catalytic performance that responds simultaneously to appropriate stimuli. The designed bio-electrodes comprise light and temperature responsive compartments, which allow the building of Boolean logic gates (i.e. ``OR'' and ``AND'') based on enzymatic communications to deliver logic operations. Electronic supplementary information (ESI) available. See DOI: 10.1039/c6nr02355j
Applied Digital Logic Exercises Using FPGAs
NASA Astrophysics Data System (ADS)
Wick, Kurt
2017-09-01
Applied Digital Logic Exercises Using FPGAs is appropriate for anyone interested in digital logic who needs to learn how to implement it through detailed exercises with state-of-the-art digital design tools and components. The book exposes readers to combinational and sequential digital logic concepts and implements them with hands-on exercises using the Verilog Hardware Description Language (HDL) and a Field Programmable Gate Arrays (FGPA) teaching board.
Testability Design Rating System: Testability Handbook. Volume 1
1992-02-01
4-10 4.7.5 Summary of False BIT Alarms (FBA) ............................. 4-10 4.7.6 Smart BIT Technique...Circuit Board PGA Pin Grid Array PLA Programmable Logic Array PLD Programmable Logic Device PN Pseudo-Random Number PREDICT Probabilistic Estimation of...11 4.7.6 Smart BIT ( reference: RADC-TR-85-198). " Smart " BIT is a term given to BIT circuitry in a system LRU which includes dedicated processor/memory
System and method for programmable bank selection for banked memory subsystems
Blumrich, Matthias A.; Chen, Dong; Gara, Alan G.; Giampapa, Mark E.; Hoenicke, Dirk; Ohmacht, Martin; Salapura, Valentina; Sugavanam, Krishnan
2010-09-07
A programmable memory system and method for enabling one or more processor devices access to shared memory in a computing environment, the shared memory including one or more memory storage structures having addressable locations for storing data. The system comprises: one or more first logic devices associated with a respective one or more processor devices, each first logic device for receiving physical memory address signals and programmable for generating a respective memory storage structure select signal upon receipt of pre-determined address bit values at selected physical memory address bit locations; and, a second logic device responsive to each of the respective select signal for generating an address signal used for selecting a memory storage structure for processor access. The system thus enables each processor device of a computing environment memory storage access distributed across the one or more memory storage structures.
Professional Learning Communities as Drivers of Educational Change: The Case of Learning Rounds
ERIC Educational Resources Information Center
Philpott, Carey; Oates, Catriona
2017-01-01
Many researchers claim that there is a compelling weight of evidence for the effectiveness of PLCs in promoting teachers' learning and pupil achievement. However, others raise fundamental questions about their nature and purpose. Some of the uncertainties about the nature and purpose of PLCs relate to the ways in which the macro-context of…
ERIC Educational Resources Information Center
Hairon, Salleh; Dimmock, Clive
2012-01-01
While the literature on professional learning communities (PLCs) has proliferated, much of it derived from and contextualised in Anglo-American settings, the concept and practice of PLCs in Asian contexts of strong hierarchies have largely been ignored. Based on literature and documentary analysis, this paper investigates the systemic…
ERIC Educational Resources Information Center
Hardman, Elizabeth L.
2012-01-01
This article describes the challenges in organizing professional learning communities (PLCs) in special education, identifies the teacher and student benefits of using a PLC approach to professional development, and discusses the promise and pitfalls of organizing web-based PLCs to engage distributed stakeholders in the practice of special…
ERIC Educational Resources Information Center
Mullen, Carol A.; Schunk, Dale H.
2010-01-01
In this discussion of professional learning communities (PLCs) in North American public schools, we examine three theoretical frames--leadership, organization, and culture. Issues related to learning are infused throughout our presentation of the frames. Based on our analysis of the current literature on this topic, PLCs offer a promising tool for…
The Effects of Professional Learning Communities on Student Achievement
ERIC Educational Resources Information Center
Burdett, John M.
2009-01-01
The purpose of this study was to examine data from the Early Childhood Longitudinal Study: Kindergarten Class of 1998-99 (ECLS-K) report, identify questions and statements that correlate to the dimensions of professional learning communities (PLCs), and determine the effect PLCs have on student achievement based on the ECLS-K data. In addition,…
ERIC Educational Resources Information Center
DeMatthews, David
2014-01-01
Professional Learning Communities (PLCs) can be powerful tools for school improvement but require principals and teachers to collaborate and work together. This article reports on a qualitative multi-case study focused on six elementary schools in West Texas that had been identified for having effective PLCs. Principals and teachers were observed…
ERIC Educational Resources Information Center
Blitz, Cynthia L.
2013-01-01
Professional learning communities (PLCs)--teams of educators who get together regularly to exchange ideas--have sprung up to meet school districts' growing interest in promoting professional development that engages teachers and administrators. PLCs meet to develop lesson plans, monitor student progress, assess instructional effectiveness, and…
ERIC Educational Resources Information Center
Padwad, Amol; Dixit, Krishna K.
2008-01-01
Teacher education seems to exhibit a shift from product-oriented mode to social constructivist, process-oriented mode of working. The emergence of professional learning communities (PLCs) of teachers may be seen as one manifestation of this shift. PLCs are increasingly seen as an effective channel for teacher learning and professional development.…
A Case Study of Certified Support Staff Members' Perceptions of Professional Learning Communities
ERIC Educational Resources Information Center
Byrd, Tresseler S.
2012-01-01
The purpose of this qualitative case study was to examine the perceptions of certified support staff at a Georgia middle school, focusing on their opinions of Professional Learning Communities (PLC), the roles they played in PLCs and the effect PLCs had on their professional practices. This descriptive case study utilized open-ended interviews,…
A Little Help from Our Friends: The Benefits and Challenges of Mandatory Teacher Collaboration
ERIC Educational Resources Information Center
Barrett, Jesse Leahn
2017-01-01
The purpose of this study was to explore secondary English teachers' perceptions of the benefits and challenges of professional learning communities (PLCs), with particular focus on what they considered to be characteristics of effective PLCs. Through a qualitative study in grounded theory using individual interviews among a subgroup of ten…
Charting New Waters: Collaborating for School Improvement in U.S. High Schools
ERIC Educational Resources Information Center
Schneider, Melanie; Huss-Lederman, Susan; Sherlock, Wallace
2012-01-01
When professional learning communities (PLCs) are developed to promote the academic achievement of English language learners (ELLs), the results can benefit not only ELLs but the whole school. This article examines the ventures of three high schools that implemented PLCs as part of a Title III National Professional Development Project. The authors…
Professional Learning Communities by Design: Putting the Learning Back into PLCs
ERIC Educational Resources Information Center
Easton, Lois Brown
2011-01-01
If you are looking for an organic approach to purpose-driven professional learning, this is the book for you. Award-winning educator Lois Brown Easton's latest work provides a compelling case study in narrative form, a chronological PLC planning outline, and first-hand "lessons learned" about how PLCs develop, mature, and sustain themselves. You…
An Undergraduate Survey Course on Asynchronous Sequential Logic, Ladder Logic, and Fuzzy Logic
ERIC Educational Resources Information Center
Foster, D. L.
2012-01-01
For a basic foundation in computer engineering, universities traditionally teach synchronous sequential circuit design, using discrete gates or field programmable gate arrays, and a microcomputers course that includes basic I/O processing. These courses, though critical, expose students to only a small subset of tools. At co-op schools like…
NASA Astrophysics Data System (ADS)
Jacobs, J. L.
1993-04-01
Erasable programmable logic devices (EPLD's) were investigated to determine their advantages and/or disadvantages in Test Equipment Engineering applications. It was found that EPLD's performed as well as or better than identical circuits using standard transistor transistor logic (TTL). The chip count in these circuits was reduced, saving printed circuit board space and shortening fabrication and prove-in time. Troubleshooting circuits of EPLD's was also easier with 10 to 100 times fewer wires needed. The reduced number of integrated circuits (IC's) contributed to faster system speeds and an overall lower power consumption. In some cases changes to the circuit became software changes using EPLD's instead of hardware changes for standard logic. Using EPLD's was fairly easy; however, as with any new technology, a learning curve must be overcome before EPLD's can be used efficiently. The many benefits of EPLD's outweighed this initial inconvenience.
G(sup 4)FET Implementations of Some Logic Circuits
NASA Technical Reports Server (NTRS)
Mojarradi, Mohammad; Akarvardar, Kerem; Cristoleveanu, Sorin; Gentil, Paul; Blalock, Benjamin; Chen, Suhan
2009-01-01
Some logic circuits have been built and demonstrated to work substantially as intended, all as part of a continuing effort to exploit the high degrees of design flexibility and functionality of the electronic devices known as G(sup 4)FETs and described below. These logic circuits are intended to serve as prototypes of more complex advanced programmable-logicdevice-type integrated circuits, including field-programmable gate arrays (FPGAs). In comparison with prior FPGAs, these advanced FPGAs could be much more efficient because the functionality of G(sup 4)FETs is such that fewer discrete components are needed to perform a given logic function in G(sup 4)FET circuitry than are needed perform the same logic function in conventional transistor-based circuitry. The underlying concept of using G(sup 4)FETs as building blocks of programmable logic circuitry was also described, from a different perspective, in G(sup 4)FETs as Universal and Programmable Logic Gates (NPO-41698), NASA Tech Briefs, Vol. 31, No. 7 (July 2007), page 44. A G(sup 4)FET can be characterized as an accumulation-mode silicon-on-insulator (SOI) metal oxide/semiconductor field-effect transistor (MOSFET) featuring two junction field-effect transistor (JFET) gates. The structure of a G(sup 4)FET (see Figure 1) is the same as that of a p-channel inversion-mode SOI MOSFET with two body contacts on each side of the channel. The top gate (G1), the substrate emulating a back gate (G2), and the junction gates (JG1 and JG2) can be biased independently of each other and, hence, each can be used to independently control some aspects of the conduction characteristics of the transistor. The independence of the actions of the four gates is what affords the enhanced functionality and design flexibility of G(sup 4)FETs. The present G(sup 4)FET logic circuits include an adjustable-threshold inverter, a real-time-reconfigurable logic gate, and a dynamic random-access memory (DRAM) cell (see Figure 2). The configuration of the adjustable-threshold inverter is similar to that of an ordinary complementary metal oxide semiconductor (CMOS) inverter except that an NMOSFET (a MOSFET having an n-doped channel and a p-doped Si substrate) is replaced by an n-channel G(sup 4)FET
Aptamer-Binding Directed DNA Origami Pattern for Logic Gates.
Yang, Jing; Jiang, Shuoxing; Liu, Xiangrong; Pan, Linqiang; Zhang, Cheng
2016-12-14
In this study, an aptamer-substrate strategy is introduced to control programmable DNA origami pattern. Combined with DNA aptamer-substrate binding and DNAzyme-cutting, small DNA tiles were specifically controlled to fill into the predesigned DNA origami frame. Here, a set of DNA logic gates (OR, YES, and AND) are performed in response to the stimuli of adenosine triphosphate (ATP) and cocaine. The experimental results are confirmed by AFM imaging and time-dependent fluorescence changes, demonstrating that the geometric patterns are regulated in a controllable and programmable manner. Our approach provides a new platform for engineering programmable origami nanopatterns and constructing complex DNA nanodevices.
Implementing a Microcontroller Watchdog with a Field-Programmable Gate Array (FPGA)
NASA Technical Reports Server (NTRS)
Straka, Bartholomew
2013-01-01
Reliability is crucial to safety. Redundancy of important system components greatly enhances reliability and hence safety. Field-Programmable Gate Arrays (FPGAs) are useful for monitoring systems and handling the logic necessary to keep them running with minimal interruption when individual components fail. A complete microcontroller watchdog with logic for failure handling can be implemented in a hardware description language (HDL.). HDL-based designs are vendor-independent and can be used on many FPGAs with low overhead.
Programmable Logic Controllers for Research on the Cyber Security of Industrial Power Plants
2017-02-12
group . 15. SUBJECT TERMS Industrial control systems, cyber security 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF a. REPORT b. ABSTRACT c. THIS...currently valid OMB control number. PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ADDRESS. 1. REPORT DATE (00-MM-YYYY) ,2. REPORT TYPE 3. DATES COVERED...From- To) 12/02/2017 Final 15 August 2015 - 12 February 2017 4. TITLE AND SUBTITLE Sa. CONTRACT NUMBER Programmable Logic Controllers for Research
46 CFR 62.25-25 - Programmable systems and devices.
Code of Federal Regulations, 2014 CFR
2014-10-01
... 46 Shipping 2 2014-10-01 2014-10-01 false Programmable systems and devices. 62.25-25 Section 62.25... AUTOMATION General Requirements for All Automated Vital Systems § 62.25-25 Programmable systems and devices. (a) Programmable control or alarm system logic must not be altered after Design Verification testing...
NASA Astrophysics Data System (ADS)
Krasilenko, Vladimir G.; Nikolsky, Alexander I.; Lazarev, Alexander A.; Lazareva, Maria V.
2010-05-01
In the paper we show that the biologically motivated conception of time-pulse encoding usage gives a set of advantages (single methodological basis, universality, tuning simplicity, learning and programming et al) at creation and design of sensor systems with parallel input-output and processing for 2D structures hybrid and next generations neuro-fuzzy neurocomputers. We show design principles of programmable relational optoelectronic time-pulse encoded processors on the base of continuous logic, order logic and temporal waves processes. We consider a structure that execute analog signal extraction, analog and time-pulse coded variables sorting. We offer optoelectronic realization of such base relational order logic element, that consists of time-pulse coded photoconverters (pulse-width and pulse-phase modulators) with direct and complementary outputs, sorting network on logical elements and programmable commutation blocks. We make technical parameters estimations of devices and processors on such base elements by simulation and experimental research: optical input signals power 0.2 - 20 uW, processing time 1 - 10 us, supply voltage 1 - 3 V, consumption power 10 - 100 uW, extended functional possibilities, learning possibilities. We discuss some aspects of possible rules and principles of learning and programmable tuning on required function, relational operation and realization of hardware blocks for modifications of such processors. We show that it is possible to create sorting machines, neural networks and hybrid data-processing systems with untraditional numerical systems and pictures operands on the basis of such quasiuniversal hardware simple blocks with flexible programmable tuning.
A Review of the Literature Related to the Change Process Schools Undergo to Sustain PLCs
ERIC Educational Resources Information Center
Jones, Christopher M.; Thessin, Rebecca A.
2015-01-01
This literature review examines the existing literature on the role of the principal in the change process to create a context for change to both develop professional learning communities (PLCs) and sustain a context of continuous improvement over time. The Brown and Anfara (2003) framework was used as a theoretical lens to analyze the literature…
ERIC Educational Resources Information Center
Regional Educational Laboratory Mid-Atlantic, 2016
2016-01-01
In this webinar, Dr. Stephanie Hirsh, Executive Director of Learning Forward, presented the research on effective PLCs and shared her experiences in creating, assessing, and leading PLCs. This Q&A addressed questions participants had for Dr. Hirsh following the webinar. The webinar recording and PowerPoint presentation are also available.
The Emerging Landscape of School-Based Professional Learning Communities in South Korean Schools
ERIC Educational Resources Information Center
Lee, Moosung; Kim, Jihyun
2016-01-01
Over the last decade, school-based professional learning communities (PLCs) have emerged as a key feature of the education system in South Korea. To understand this relatively new phenomenon in the context of South Korea, we provide a review of research on school-based PLCs in South Korea and an empirical analysis of the Teaching and Learning…
ERIC Educational Resources Information Center
Zhang, Jia; Yuan, Rui; Yu, Shulin
2017-01-01
Using qualitative data collected from three high schools in Shanghai, this study explored the barriers to the development of professional learning communities (PLCs) in Chinese schools from the perspectives of school leaders and teachers. Results indicate that the barriers identified by teachers in the development of PLCs include insufficient…
ERIC Educational Resources Information Center
Thacker, Teresa D.
2013-01-01
Professional Learning Communities (PLCs) are an emerging form of professional learning used nationwide as a means for educators to focus on job-embedded learning. Extensive qualitative data have been compiled regarding the perception of educators and PLCs. However, little quantitative research has been conducted regarding the academic achievement…
ERIC Educational Resources Information Center
Peppers, Gloria J.
2014-01-01
The purpose of this study was to explore teachers' perceptions prior to the implementation of professional learning communities (PLCs) and after the implementation of PLCs in a large suburban high school. The goal was to provide information that focused on (a) retention and achievement of students, (b) retention of teachers, and (c) teachers'…
A novel productivity-driven logic element for field-programmable devices
NASA Astrophysics Data System (ADS)
Marconi, Thomas; Bertels, Koen; Gaydadjiev, Georgi
2014-06-01
Although various techniques have been proposed for power reduction in field-programmable devices (FPDs), they are still all based on conventional logic elements (LEs). In the conventional LE, the output of the combinational logic (e.g. the look-up table (LUT) in many field-programmable gate arrays (FPGAs)) is connected to the input of the storage element; while the D flip-flop (DFF) is always clocked even when not necessary. Such unnecessary transitions waste power. To address this problem, we propose a novel productivity-driven LE with reduced number of transitions. The differences between our LE and the conventional LE are in the FFs-type used and the internal LE organisation. In our LEs, DFFs have been replaced by T flip-flops with the T input permanently connected to logic value 1. Instead of connecting the output of the combinational logic to the FF input, we use it as the FF clock. The proposed LE has been validated via Simulation Program with Integrated Circuit Emphasis (SPICE) simulations for a 45-nm Complementary Metal-Oxide-Semiconductor (CMOS) technology as well as via a real Computer-Aided Design (CAD) tools on a real FPGA using the standard Microelectronic Center of North Carolina (MCNC) benchmark circuits. The experimental results show that FPDs using our proposal not only have 48% lower total power but also run 17% faster than conventional FPDs on average.
Programmable bioelectronics in a stimuli-encoded 3D graphene interface.
Parlak, Onur; Beyazit, Selim; Tse-Sum-Bui, Bernadette; Haupt, Karsten; Turner, Anthony P F; Tiwari, Ashutosh
2016-05-21
The ability to program and mimic the dynamic microenvironment of living organisms is a crucial step towards the engineering of advanced bioelectronics. Here, we report for the first time a design for programmable bioelectronics, with 'built-in' switchable and tunable bio-catalytic performance that responds simultaneously to appropriate stimuli. The designed bio-electrodes comprise light and temperature responsive compartments, which allow the building of Boolean logic gates (i.e."OR" and "AND") based on enzymatic communications to deliver logic operations.
Starting Circuit For Erasable Programmable Logic Device
NASA Technical Reports Server (NTRS)
Cole, Steven W.
1990-01-01
Voltage regulator bypassed to supply starting current. Starting or "pullup" circuit supplies large inrush of current required by erasable programmable logic device (EPLD) while being turned on. Operates only during such intervals of high demand for current and has little effect any other time. Performs needed bypass, acting as current-dependent shunt connecting battery or other source of power more nearly directly to EPLD. Input capacitor of regulator removed when starting circuit installed, reducing probability of damage to transistor in event of short circuit in or across load.
Flexible programmable logic module
Robertson, Perry J.; Hutchinson, Robert L.; Pierson, Lyndon G.
2001-01-01
The circuit module of this invention is a VME board containing a plurality of programmable logic devices (PLDs), a controlled impedance clock tree, and interconnecting buses. The PLDs are arranged to permit systolic processing of a problem by offering wide data buses and a plurality of processing nodes. The board contains a clock reference and clock distribution tree that can drive each of the PLDs with two critically timed clock references. External clock references can be used to drive additional circuit modules all operating from the same synchronous clock reference.
Molecular implementation of simple logic programs.
Ran, Tom; Kaplan, Shai; Shapiro, Ehud
2009-10-01
Autonomous programmable computing devices made of biomolecules could interact with a biological environment and be used in future biological and medical applications. Biomolecular implementations of finite automata and logic gates have already been developed. Here, we report an autonomous programmable molecular system based on the manipulation of DNA strands that is capable of performing simple logical deductions. Using molecular representations of facts such as Man(Socrates) and rules such as Mortal(X) <-- Man(X) (Every Man is Mortal), the system can answer molecular queries such as Mortal(Socrates)? (Is Socrates Mortal?) and Mortal(X)? (Who is Mortal?). This biomolecular computing system compares favourably with previous approaches in terms of expressive power, performance and precision. A compiler translates facts, rules and queries into their molecular representations and subsequently operates a robotic system that assembles the logical deductions and delivers the result. This prototype is the first simple programming language with a molecular-scale implementation.
ERIC Educational Resources Information Center
Maynor, Chad Edward
2010-01-01
Professional learning communities (PLCs) provide schools with a tool to meet the professional development needs of their teachers through ongoing, job-embedded staff development designed to improve instruction and student learning. While research exists on the development of PLCs, there is a gap in the literature concerning the principal's role in…
Science-for-Teaching Discourse in Science Teachers' Professional Learning Communities
NASA Astrophysics Data System (ADS)
Lohwasser, Karin
Professional learning communities (PLCs) provide an increasingly common structure for teachers' professional development. The effectiveness of PLCs depends on the content and quality of the participants' discourse. This dissertation was conducted to add to an understanding of the science content needed to prepare to teach science, and the discourse characteristics that create learning opportunities in teachers' PLCs. To this end, this study examined how middle school science teachers in three PLCs addressed science-for-teaching, and to what effect. Insight into discourse about content knowledge for teaching in PLCs has implications for the analysis, interpretation, and support of teachers' professional discourse, their collaborative learning, and consequently their improvement of practice. This dissertation looked closely at the hybrid space between teachers' knowledge of students, of teaching, and of science, and how this space was explored in the discourse among teachers, and between teachers and science experts. At the center of the study were observations of three 2-day PLC cycles in which participants worked together to improve the way they taught their curriculum. Two of the PLC cycles were supported, in part, by a science expert who helped the teachers explore the science they needed for teaching. The third PLC worked without such support. The following overarching questions were explored in the three articles of this dissertation: (1) What kind of science knowledge did teachers discuss in preparation for teaching? (2) How did the teachers talk about content knowledge for science teaching, and to what effect for their teaching practice? (3) How did collaborating teachers' discursive accountabilities provide opportunities for furthering the teachers' content knowledge for science teaching? The teachers' discourse during the 2-day collaboration cycles was analyzed and interpreted based on a sociocultural framework that included concepts from the practice-based theory of content knowledge for teaching developed by D. L. Ball, Thames, and Phelps (2008) and the Accountable Talk framework by Michaels, O'Connor, & Resnick (2008). The study's findings could provide justification for and ideas on how to provide targeted support for PLCs to make teachers' work on science knowledge more applicable to lesson planning, teaching, and student learning.
Singh, Amarjeet; Kanwar, Poonam; Pandey, Amita; Tyagi, Akhilesh K.; Sopory, Sudhir K.; Kapoor, Sanjay; Pandey, Girdhar K.
2013-01-01
Background Phospholipase C (PLC) is one of the major lipid hydrolysing enzymes, implicated in lipid mediated signaling. PLCs have been found to play a significant role in abiotic stress triggered signaling and developmental processes in various plant species. Genome wide identification and expression analysis have been carried out for this gene family in Arabidopsis, yet not much has been accomplished in crop plant rice. Methodology/Principal Findings An exhaustive in-silico exploration of rice genome using various online databases and tools resulted in the identification of nine PLC encoding genes. Based on sequence, motif and phylogenetic analysis rice PLC gene family could be divided into phosphatidylinositol-specific PLCs (PI-PLCs) and phosphatidylcholine- PLCs (PC-PLC or NPC) classes with four and five members, respectively. A comparative analysis revealed that PLCs are conserved in Arabidopsis (dicots) and rice (monocot) at gene structure and protein level but they might have evolved through a separate evolutionary path. Transcript profiling using gene chip microarray and quantitative RT-PCR showed that most of the PLC members expressed significantly and differentially under abiotic stresses (salt, cold and drought) and during various developmental stages with condition/stage specific and overlapping expression. This finding suggested an important role of different rice PLC members in abiotic stress triggered signaling and plant development, which was also supported by the presence of relevant cis-regulatory elements in their promoters. Sub-cellular localization of few selected PLC members in Nicotiana benthamiana and onion epidermal cells has provided a clue about their site of action and functional behaviour. Conclusion/Significance The genome wide identification, structural and expression analysis and knowledge of sub-cellular localization of PLC gene family envisage the functional characterization of these genes in crop plants in near future. PMID:23638098
Singh, Amarjeet; Kanwar, Poonam; Pandey, Amita; Tyagi, Akhilesh K; Sopory, Sudhir K; Kapoor, Sanjay; Pandey, Girdhar K
2013-01-01
Phospholipase C (PLC) is one of the major lipid hydrolysing enzymes, implicated in lipid mediated signaling. PLCs have been found to play a significant role in abiotic stress triggered signaling and developmental processes in various plant species. Genome wide identification and expression analysis have been carried out for this gene family in Arabidopsis, yet not much has been accomplished in crop plant rice. An exhaustive in-silico exploration of rice genome using various online databases and tools resulted in the identification of nine PLC encoding genes. Based on sequence, motif and phylogenetic analysis rice PLC gene family could be divided into phosphatidylinositol-specific PLCs (PI-PLCs) and phosphatidylcholine- PLCs (PC-PLC or NPC) classes with four and five members, respectively. A comparative analysis revealed that PLCs are conserved in Arabidopsis (dicots) and rice (monocot) at gene structure and protein level but they might have evolved through a separate evolutionary path. Transcript profiling using gene chip microarray and quantitative RT-PCR showed that most of the PLC members expressed significantly and differentially under abiotic stresses (salt, cold and drought) and during various developmental stages with condition/stage specific and overlapping expression. This finding suggested an important role of different rice PLC members in abiotic stress triggered signaling and plant development, which was also supported by the presence of relevant cis-regulatory elements in their promoters. Sub-cellular localization of few selected PLC members in Nicotiana benthamiana and onion epidermal cells has provided a clue about their site of action and functional behaviour. The genome wide identification, structural and expression analysis and knowledge of sub-cellular localization of PLC gene family envisage the functional characterization of these genes in crop plants in near future.
Zhang, Lei; Wang, Huaxi; Yang, Yan; Liu, Hui; Zhang, Qihao; Xiang, Qi; Ge, Renshan; Su, Zhijian; Huang, Yadong
2013-06-28
Nerve growth factor (NGF) has been reported to be involved in male reproductive physiology. However, few reports have described the activity of NGF during Leydig cell development. The objective of the present study was to examine the role of NGF during stem-Leydig-cell (SLC) regeneration. We investigated the effects of NGF on Leydig-cell (LC) regeneration by measuring mRNA levels in the adult rat testis after ethane dimethanesulfonate (EDS) treatment. Furthermore, we used the established organ culture model of rat seminiferous tubules to examine the regulation of NGF during SLC proliferation and differentiation using EdU staining, real-time PCR and western blotting. Progenitor Leydig cells (PLCs) and immature Leydig cells (ILCs) were also used to investigate the effects of NGF on LCs at different developmental stages. NGF mRNA levels changed significantly during Leydig-cell regeneration in vivo. In vitro, NGF significantly promoted the proliferation of stem Leydig cells and also induced steroidogenic enzyme gene expression and 3β-HSD protein expression. The data from PLCs and ILCs showed that NGF could increase Cyclin D1 and Hsd 17b3 mRNA levels in PLCs and Cyclin D1 mRNA levels in ILCs. These results indicate that NGF may play an important role during LC regeneration by regulating the proliferation and differentiation of LCs at different developmental stages, from SLCs to PLCs and from PLCs to ILCs. The discovery of this effect of NGF on Leydig cells will provide useful information for developing new potential therapies for PADAM (Partial Androgen Deficiency in the Aging Male). Copyright © 2013 Elsevier Inc. All rights reserved.
Bakala N'goma, J C; Schué, M; Carrière, F; Geerlof, A; Canaan, S
2010-12-01
Phospholipase Cs (PLCs) contribute importantly to the virulence and pathogenicity of several bacteria. It has been reported in previous studies that mutations in the four predicted plc genes of Mycobacterium tuberculosis inhibit the growth of these bacteria during the late phase of infection in mice. These enzymes have not yet been fully characterised, mainly because they are not easy to produce in large quantities. With a view to elucidating the role of all Mycobacterium tuberculosis phospholipase Cs (PLC-A, PLC-B, PLC-C and PLC-D), a large amount of active, soluble recombinant PLCs, were expressed and purified using Mycobacterium smegmatis as expression system. These enzymes showed different pH activity profiles. PLC-C was found to be the most active of the four recombinant PLCs under acidic conditions. All the enzymes tested induced cytotoxic effects on mouse macrophage RAW 264.7 cell lines, via direct or indirect enzymatic hydrolysis of cell membrane phospholipids. These results open new prospects for characterising biochemical and structural features of Mycobacterium tuberculosis PLCs, which might lead to the identification of novel anti-tuberculosis drug targets. All mycobacterial phospholipase Cs can now be studied in order to determine their role in the virulence and pathogenicity of bacteria of this kind. 2010 Elsevier B.V. All rights reserved.
Electrically reconfigurable logic array
NASA Technical Reports Server (NTRS)
Agarwal, R. K.
1982-01-01
To compose the complicated systems using algorithmically specialized logic circuits or processors, one solution is to perform relational computations such as union, division and intersection directly on hardware. These relations can be pipelined efficiently on a network of processors having an array configuration. These processors can be designed and implemented with a few simple cells. In order to determine the state-of-the-art in Electrically Reconfigurable Logic Array (ERLA), a survey of the available programmable logic array (PLA) and the logic circuit elements used in such arrays was conducted. Based on this survey some recommendations are made for ERLA devices.
G4-FETs as Universal and Programmable Logic Gates
NASA Technical Reports Server (NTRS)
Johnson, Travis; Fijany, Amir; Mojarradi, Mohammad; Vatan, Farrokh; Toomarian, Nikzad; Kolawa, Elizabeth; Cristoloveanu, Sorin; Blalock, Benjamin
2007-01-01
An analysis of a patented generic silicon- on-insulator (SOI) electronic device called a G4-FET has revealed that the device could be designed to function as a universal and programmable logic gate. The universality and programmability could be exploited to design logic circuits containing fewer discrete components than are required for conventional transistor-based circuits performing the same logic functions. A G4-FET is a combination of a junction field-effect transistor (JFET) and a metal oxide/semiconductor field-effect transistor (MOSFET) superimposed in a single silicon island and can therefore be regarded as two transistors sharing the same body. A G4-FET can also be regarded as a single transistor having four gates: two side junction-based gates, a top MOS gate, and a back gate activated by biasing of the SOI substrate. Each of these gates can be used to control the conduction characteristics of the transistor; this possibility creates new options for designing analog, radio-frequency, mixed-signal, and digital circuitry. With proper choice of the specific dimensions for the gates, channels, and ancillary features of the generic G4-FET, the device could be made to function as a three-input, one-output logic gate. As illustrated by the truth table in the top part of the figure, the behavior of this logic gate would be the inverse (the NOT) of that of a majority gate. In other words, the device would function as a NOT-majority gate. By simply adding an inverter, one could obtain a majority gate. In contrast, to construct a majority gate in conventional complementary metal oxide/semiconductor (CMOS) circuitry, one would need four three-input AND gates and a four-input OR gate, altogether containing 32 transistors.
ERIC Educational Resources Information Center
Talkmitt, Marcia Joy
2013-01-01
The purpose of this study was to explore the evolution of collaborative practices of PLCs as they emerge when using technology based formative assessment via iFAIT or innovative Formative Assessment with Instruction and Technology developed by the researcher using audience response systems and the online data compiler, Eduphoria!. This study used…
Research of Characteristics of the Low Voltage Power Line in Underground Coal Mine
NASA Astrophysics Data System (ADS)
Wei, Shaoliang; Qin, Shiqun; Gao, Wenchang; Cheng, Fengyu; Cao, Zhongyue
The power line communications (PLCs) can count on existing electrical connections reaching each corner in the locations where such applications are required, so signal transmission over power lines is nowadays gaining more and more interest for applications like internet. The research of characteristics of the low voltage power line is the fundamental and importance task. This work presents a device to test the characteristics of the low voltage power line. The low voltage power line channel characteristics overground and the channel characteristics underground were tested in using this device. Experiments show that, the characteristics are different between the PLCs channel underground coal mine and the PLC channel overground. Different technology should be adopted to structure the PLCs channel model underground coal mine and transmit high speed digital signal. But how to use the technology better to the high-speed digital communication under coal mine is worth of further studying.
You, Mingxu; Zhu, Guizhi; Chen, Tao; Donovan, Michael J; Tan, Weihong
2015-01-21
The specific inventory of molecules on diseased cell surfaces (e.g., cancer cells) provides clinicians an opportunity for accurate diagnosis and intervention. With the discovery of panels of cancer markers, carrying out analyses of multiple cell-surface markers is conceivable. As a trial to accomplish this, we have recently designed a DNA-based device that is capable of performing autonomous logic-based analysis of two or three cancer cell-surface markers. Combining the specific target-recognition properties of DNA aptamers with toehold-mediated strand displacement reactions, multicellular marker-based cancer analysis can be realized based on modular AND, OR, and NOT Boolean logic gates. Specifically, we report here a general approach for assembling these modular logic gates to execute programmable and higher-order profiling of multiple coexisting cell-surface markers, including several found on cancer cells, with the capacity to report a diagnostic signal and/or deliver targeted photodynamic therapy. The success of this strategy demonstrates the potential of DNA nanotechnology in facilitating targeted disease diagnosis and effective therapy.
NASA Astrophysics Data System (ADS)
Oztekin, Halit; Temurtas, Feyzullah; Gulbag, Ali
The Arithmetic and Logic Unit (ALU) design is one of the important topics in Computer Architecture and Organization course in Computer and Electrical Engineering departments. There are ALU designs that have non-modular nature to be used as an educational tool. As the programmable logic technology has developed rapidly, it is feasible that ALU design based on Field Programmable Gate Array (FPGA) is implemented in this course. In this paper, we have adopted the modular approach to ALU design based on FPGA. All the modules in the ALU design are realized using schematic structure on Altera's Cyclone II Development board. Under this model, the ALU content is divided into four distinct modules. These are arithmetic unit except for multiplication and division operations, logic unit, multiplication unit and division unit. User can easily design any size of ALU unit since this approach has the modular nature. Then, this approach was applied to microcomputer architecture design named BZK.SAU.FPGA10.0 instead of the current ALU unit.
FAST TRACK COMMUNICATION: Reversible arithmetic logic unit for quantum arithmetic
NASA Astrophysics Data System (ADS)
Kirkedal Thomsen, Michael; Glück, Robert; Axelsen, Holger Bock
2010-09-01
This communication presents the complete design of a reversible arithmetic logic unit (ALU) that can be part of a programmable reversible computing device such as a quantum computer. The presented ALU is garbage free and uses reversible updates to combine the standard reversible arithmetic and logical operations in one unit. Combined with a suitable control unit, the ALU permits the construction of an r-Turing complete computing device. The garbage-free ALU developed in this communication requires only 6n elementary reversible gates for five basic arithmetic-logical operations on two n-bit operands and does not use ancillae. This remarkable low resource consumption was achieved by generalizing the V-shape design first introduced for quantum ripple-carry adders and nesting multiple V-shapes in a novel integrated design. This communication shows that the realization of an efficient reversible ALU for a programmable computing device is possible and that the V-shape design is a very versatile approach to the design of quantum networks.
Huang, Wei Tao; Luo, Hong Qun; Li, Nian Bing
2014-05-06
The most serious, and yet unsolved, problem of constructing molecular computing devices consists in connecting all of these molecular events into a usable device. This report demonstrates the use of Boolean logic tree for analyzing the chemical event network based on graphene, organic dye, thrombin aptamer, and Fenton reaction, organizing and connecting these basic chemical events. And this chemical event network can be utilized to implement fluorescent combinatorial logic (including basic logic gates and complex integrated logic circuits) and fuzzy logic computing. On the basis of the Boolean logic tree analysis and logic computing, these basic chemical events can be considered as programmable "words" and chemical interactions as "syntax" logic rules to construct molecular search engine for performing intelligent molecular search query. Our approach is helpful in developing the advanced logic program based on molecules for application in biosensing, nanotechnology, and drug delivery.
ERIC Educational Resources Information Center
Ahn, Joonkil
2017-01-01
This study intends to identify some key factors in creating and sustaining school-based teacher professional learning communities (PLCs) through a case study of a South Korean public high school. To achieve this, the study identified some essential infrastructure, preparation, and necessary social organization for creating PLCs. The ideal unit and…
Flight dynamics analysis and simulation of heavy lift airships. Volume 5: Programmer's manual
NASA Technical Reports Server (NTRS)
Ringland, R. F.; Tischler, M. B.; Jex, H. R.; Emmen, R. D.; Ashkenas, I. L.
1982-01-01
The Programmer's Manual contains explanations of the logic embodied in the various program modules, a dictionary of program variables, a subroutine listing, subroutine/common block/cross reference listing, and a calling/called subroutine cross reference listing.
NASA Technical Reports Server (NTRS)
Ng, Tak-kwong (Inventor); Herath, Jeffrey A. (Inventor)
2010-01-01
An integrated system mitigates the effects of a single event upset (SEU) on a reprogrammable field programmable gate array (RFPGA). The system includes (i) a RFPGA having an internal configuration memory, and (ii) a memory for storing a configuration associated with the RFPGA. Logic circuitry programmed into the RFPGA and coupled to the memory reloads a portion of the configuration from the memory into the RFPGA's internal configuration memory at predetermined times. Additional SEU mitigation can be provided by logic circuitry on the RFPGA that monitors and maintains synchronized operation of the RFPGA's digital clock managers.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhang, Lei; Wang, Huaxi; Yang, Yan
Highlights: •Nerve growth factor has shown significant changes on mRNA levels during Adult Leydig cells regeneration. •We established the organ culture model of rat seminiferous tubules with ethane dimethyl sulphonate (EDS) treatment. •Nerve growth factor has shown proliferation and differentiation-promoting effects on Adult stem Leydig cells. •Nerve growth factor induces progenitor Leydig cells to proliferate and differentiate and immature Leydig cells to proliferate. -- Abstract: Nerve growth factor (NGF) has been reported to be involved in male reproductive physiology. However, few reports have described the activity of NGF during Leydig cell development. The objective of the present study was tomore » examine the role of NGF during stem-Leydig-cell (SLC) regeneration. We investigated the effects of NGF on Leydig-cell (LC) regeneration by measuring mRNA levels in the adult rat testis after ethane dimethanesulfonate (EDS) treatment. Furthermore, we used the established organ culture model of rat seminiferous tubules to examine the regulation of NGF during SLC proliferation and differentiation using EdU staining, real-time PCR and western blotting. Progenitor Leydig cells (PLCs) and immature Leydig cells (ILCs) were also used to investigate the effects of NGF on LCs at different developmental stages. NGF mRNA levels changed significantly during Leydig-cell regeneration in vivo. In vitro, NGF significantly promoted the proliferation of stem Leydig cells and also induced steroidogenic enzyme gene expression and 3β-HSD protein expression. The data from PLCs and ILCs showed that NGF could increase Cyclin D1 and Hsd 17b3 mRNA levels in PLCs and Cyclin D1 mRNA levels in ILCs. These results indicate that NGF may play an important role during LC regeneration by regulating the proliferation and differentiation of LCs at different developmental stages, from SLCs to PLCs and from PLCs to ILCs. The discovery of this effect of NGF on Leydig cells will provide useful information for developing new potential therapies for PADAM (Partial Androgen Deficiency in the Aging Male)« less
Hernández-Enríquez, Marco; Lairez, Olivier; Campelo-Parada, Francisco; Lhermusier, Thibault; Bouisset, Frédéric; Roncalli, Jérôme; Elbaz, Meyer; Carrié, Didier; Boudou, Nicolas
2018-05-28
To compare outcomes in patients receiving polytetrafluoroethylene (PTFE) and polyurethane (PL) covered stents (CS) after coronary artery perforation (CAP). The prognosis of CAP has improved with the advent of CSs. Information is scarce about the outcomes of new-generation CSs. Sixty-one patients were treated with CSs in a 5-years period (age = 77 ± 8.75% males). Procedural and clinical data were retrospectively collected. The primary endpoint was procedural success. Secondary endpoints included death and major adverse cardiac events (MACE) defined as a composite of death, myocardial infarction, target vessel, and lesion revascularization and need for surgical repair). Twenty-two (36%) received PL-CSs and 39 (65%) PTFE-CSs. There were no differences in procedural success (86% vs 69%, P = 0.216). Time to deliver was shorter with PL-CS despite larger length of stents (8[11] vs 15[16] min, P = 0.001; 20[5] vs 16[3] mm, P < 0.001). This group had lower rate of pericardial effusion and cardiac arrest (41% vs 72%, P = 0.028; 5% vs 26%, P = 0.045). At 1-year follow-up, MACE rates were similar (58% vs 56%, P = 1.000) with atrend toward TVR in the PL-CS arm (21% vs 5%, P = 0.083). No differences were found in mortality (26% vs 41%, P = 0.385). Each group had 1 stent thrombosis and in-stent restenosis trended higher in the PL-CS group (12% vs 3%, P = 0.223). Time to deliver was shorter with the PL-CS and resulted in lower rate of pericardial effusion and cardiac arrest. However, there were no significant differences in procedural success and 1-year follow-up MACE in patients treated with PL-CS or PTFE-CS. © 2018, Wiley Periodicals, Inc.
NASA Astrophysics Data System (ADS)
Horowitz, Paul; Hill, Winfield
2015-04-01
1. Foundations; 2. Bipolar transistors; 3. Field effect transistors; 4. Operational amplifiers; 5. Precision circuits; 6. Filters; 7. Oscillators and timers; 8. Low noise techniques and transimpedance; 9. Power regulation; 10. Digital electronics; 11. Programmable logic devices; 12. Logical interfacing; 13. Digital meets analog; 14. Computers, controllers, and data links; 15. Microcontrollers.
Optical triple-in digital logic using nonlinear optical four-wave mixing
NASA Astrophysics Data System (ADS)
Widjaja, Joewono; Tomita, Yasuo
1995-08-01
A new programmable optical processor is proposed for implementing triple-in combinatorial digital logic that uses four-wave mixing. Binary-coded decimal-to-octal decoding is experimentally demonstrated by use of a photorefractive BaTiO 3 crystal. The result confirms the feasibility of the proposed system.
A String Search Marketing Application Using Visual Programming
ERIC Educational Resources Information Center
Chin, Jerry M.; Chin, Mary H.; Van Landuyt, Cathryn
2013-01-01
This paper demonstrates the use of programing software that provides the student programmer visual cues to construct the code to a student programming assignment. This method does not disregard or minimize the syntax or required logical constructs. The student can concentrate more on the logic and less on the language itself.
2017-03-01
Implementation of a Loosely-Coupled Lockstep Approach in the Xilinx Zynq-7000 All Programmable SoC™ for High Consequence Applications Ryan D...sandia.gov Abstract: For high consequence applications requiring information assurance, the architecture of the Xilinx Zynq- 7000 All Programmable ...transaction checker residing in the Programmable Logic portion of the Zynq device will be discussed along with implementation results and latency
NASA Technical Reports Server (NTRS)
Rickard, D. A.; Bodenheimer, R. E.
1976-01-01
Digital computer components which perform two dimensional array logic operations (Tse logic) on binary data arrays are described. The properties of Golay transforms which make them useful in image processing are reviewed, and several architectures for Golay transform processors are presented with emphasis on the skeletonizing algorithm. Conventional logic control units developed for the Golay transform processors are described. One is a unique microprogrammable control unit that uses a microprocessor to control the Tse computer. The remaining control units are based on programmable logic arrays. Performance criteria are established and utilized to compare the various Golay transform machines developed. A critique of Tse logic is presented, and recommendations for additional research are included.
NASA Astrophysics Data System (ADS)
Krasilenko, Vladimir G.; Bardachenko, Vitaliy F.; Nikolsky, Alexander I.; Lazarev, Alexander A.
2007-04-01
In the paper we show that the biologically motivated conception of the use of time-pulse encoding gives the row of advantages (single methodological basis, universality, simplicity of tuning, training and programming et al) at creation and designing of sensor systems with parallel input-output and processing, 2D-structures of hybrid and neuro-fuzzy neurocomputers of next generations. We show principles of construction of programmable relational optoelectronic time-pulse coded processors, continuous logic, order logic and temporal waves processes, that lie in basis of the creation. We consider structure that executes extraction of analog signal of the set grade (order), sorting of analog and time-pulse coded variables. We offer optoelectronic realization of such base relational elements of order logic, which consists of time-pulse coded phototransformers (pulse-width and pulse-phase modulators) with direct and complementary outputs, sorting network on logical elements and programmable commutations blocks. We make estimations of basic technical parameters of such base devices and processors on their basis by simulation and experimental research: power of optical input signals - 0.200-20 μW, processing time - microseconds, supply voltage - 1.5-10 V, consumption power - hundreds of microwatts per element, extended functional possibilities, training possibilities. We discuss some aspects of possible rules and principles of training and programmable tuning on the required function, relational operation and realization of hardware blocks for modifications of such processors. We show as on the basis of such quasiuniversal hardware simple block and flexible programmable tuning it is possible to create sorting machines, neural networks and hybrid data-processing systems with the untraditional numerical systems and pictures operands.
Program to Optimize Simulated Trajectories (POST). Volume 3: Programmer's manual
NASA Technical Reports Server (NTRS)
Brauer, G. L.; Cornick, D. E.; Habeger, A. R.; Petersen, F. M.; Stevenson, R.
1975-01-01
Information pertinent to the programmer and relating to the program to optimize simulated trajectories (POST) is presented. Topics discussed include: program structure and logic, subroutine listings and flow charts, and internal FORTRAN symbols. The POST core requirements are summarized along with program macrologic.
A DNAzyme-mediated logic gate for programming molecular capture and release on DNA origami.
Li, Feiran; Chen, Haorong; Pan, Jing; Cha, Tae-Gon; Medintz, Igor L; Choi, Jong Hyun
2016-06-28
Here we design a DNA origami-based site-specific molecular capture and release platform operated by a DNAzyme-mediated logic gate process. We show the programmability and versatility of this platform with small molecules, proteins, and nanoparticles, which may also be controlled by external light signals.
Nonvolatile reconfigurable sequential logic in a HfO2 resistive random access memory array.
Zhou, Ya-Xiong; Li, Yi; Su, Yu-Ting; Wang, Zhuo-Rui; Shih, Ling-Yi; Chang, Ting-Chang; Chang, Kuan-Chang; Long, Shi-Bing; Sze, Simon M; Miao, Xiang-Shui
2017-05-25
Resistive random access memory (RRAM) based reconfigurable logic provides a temporal programmable dimension to realize Boolean logic functions and is regarded as a promising route to build non-von Neumann computing architecture. In this work, a reconfigurable operation method is proposed to perform nonvolatile sequential logic in a HfO 2 -based RRAM array. Eight kinds of Boolean logic functions can be implemented within the same hardware fabrics. During the logic computing processes, the RRAM devices in an array are flexibly configured in a bipolar or complementary structure. The validity was demonstrated by experimentally implemented NAND and XOR logic functions and a theoretically designed 1-bit full adder. With the trade-off between temporal and spatial computing complexity, our method makes better use of limited computing resources, thus provides an attractive scheme for the construction of logic-in-memory systems.
Programmable and Multiparameter DNA-Based Logic Platform For Cancer Recognition and Targeted Therapy
2014-01-01
The specific inventory of molecules on diseased cell surfaces (e.g., cancer cells) provides clinicians an opportunity for accurate diagnosis and intervention. With the discovery of panels of cancer markers, carrying out analyses of multiple cell-surface markers is conceivable. As a trial to accomplish this, we have recently designed a DNA-based device that is capable of performing autonomous logic-based analysis of two or three cancer cell-surface markers. Combining the specific target-recognition properties of DNA aptamers with toehold-mediated strand displacement reactions, multicellular marker-based cancer analysis can be realized based on modular AND, OR, and NOT Boolean logic gates. Specifically, we report here a general approach for assembling these modular logic gates to execute programmable and higher-order profiling of multiple coexisting cell-surface markers, including several found on cancer cells, with the capacity to report a diagnostic signal and/or deliver targeted photodynamic therapy. The success of this strategy demonstrates the potential of DNA nanotechnology in facilitating targeted disease diagnosis and effective therapy. PMID:25361164
Programmable Regulation of DNA Conjugation to Gold Nanoparticles via Strand Displacement.
Zhang, Cheng; Wu, Ranfeng; Li, Yifan; Zhang, Qiang; Yang, Jing
2017-10-31
Methods for conjugating DNA to gold nanoparticles (AuNPs) have recently attracted considerable attention. The ability to control such conjugation in a programmable way is of great interest. Here, we have developed a logic-based method for manipulating the conjugation of thiolated DNA species to AuNPs via cascading DNA strand displacement. Using this method, several logic-based operation systems are established and up to three kinds of DNA signals are introduced at the same time. In addition, a more sensitive catalytic logic-based operation is also achieved based on an entropy-driven process. In the experiment, all of the DNA/AuNPs conjugation results are verified by agrose gel. This strategy promises great potential for automatically conjugating DNA stands onto label-free gold nanoparticles and can be extended to constructing DNA/nanoparticle devices for applications in diagnostics, biosensing, and molecular robotics.
Assurance of Complex Electronics. What Path Do We Take?
NASA Technical Reports Server (NTRS)
Plastow, Richard A.
2007-01-01
Many of the methods used to develop software bare a close resemblance to Complex Electronics (CE) development. CE are now programmed to perform tasks that were previously handled in software, such as communication protocols. For instance, Field Programmable Gate Arrays (FPGAs) can have over a million logic gates while system-on-chip (SOC) devices can combine a microprocessor, input and output channels, and sometimes an FPGA for programmability. With this increased intricacy, the possibility of "software-like" bugs such as incorrect design, logic, and unexpected interactions within the logic is great. Since CE devices are obscuring the hardware/software boundary, we propose that mature software methodologies may be utilized with slight modifications to develop these devices. By using standardized S/W Engineering methods such as checklists, missing requirements and "bugs" can be detected earlier in the development cycle, thus creating a development process for CE that will be easily maintained and configurable based on the device used.
Design and implementation of projects with Xilinx Zynq FPGA: a practical case
NASA Astrophysics Data System (ADS)
Travaglini, R.; D'Antone, I.; Meneghini, S.; Rignanese, L.; Zuffa, M.
The main advantage when using FPGAs with embedded processors is the availability of additional several high-performance resources in the same physical device. Moreover, the FPGA programmability allows for connect custom peripherals. Xilinx have designed a programmable device named Zynq-7000 (simply called Zynq in the following), which integrates programmable logic (identical to the other Xilinx "serie 7" devices) with a System on Chip (SOC) based on two embedded ARM processors. Since both parts are deeply connected, the designers benefit from performance of hardware SOC and flexibility of programmability as well. In this paper a design developed by the Electronic Design Department at the Bologna Division of INFN will be presented as a practical case of project based on Zynq device. It is developed by using a commercial board called ZedBoard hosting a FMC mezzanine with a 12-bit 500 MS/s ADC. The Zynq FPGA on the ZedBoard receives digital outputs from the ADC and send them to the acquisition PC, after proper formatting, through a Gigabit Ethernet link. The major focus of the paper will be about the methodology to develop a Zynq-based design with the Xilinx Vivado software, enlightening how to configure the SOC and connect it with the programmable logic. Firmware design techniques will be presented: in particular both VHDL and IP core based strategies will be discussed. Further, the procedure to develop software for the embedded processor will be presented. Finally, some debugging tools, like the embedded Logic Analyzer, will be shown. Advantages and disadvantages with respect to adopting FPGA without embedded processors will be discussed.
Programmable Logic Application Notes
NASA Technical Reports Server (NTRS)
Katz, Richard
1999-01-01
This column will be provided each quarter as a source for reliability, radiation results, NASA capabilities, and other information on programmable logic devices and related applications. This quarter the focus is on some experimental data on low voltage drop out regulators to support mixed 5 and 3.3 volt systems. A discussion of the Small Explorer WIRE spacecraft will also be given. Lastly, we show take a first look at robust state machines in Hardware Description Languages (VHDL) and their use in critical systems. If you have information that you would like to submit or an area you would like discussed or researched, please give me a call or e-mail.
NASA Technical Reports Server (NTRS)
Heinmiller, J. P.
1971-01-01
This document is the programmer's guide for the GNAT computer program developed under MSC/TRW Task 705-2, Apollo cryogenic storage system analysis, subtask 2, is reported. Detailed logic flow charts and compiled program listings are provided for all program elements.
NASA Technical Reports Server (NTRS)
Dick, J. W.; Benda, B. J.
1975-01-01
User and programmer oriented documentation for the flexible body option of the Takeoff and Landing Analysis (TOLA) computer program are provided. The user information provides sufficient knowledge of the development and use of the option to enable the engineering user to successfully operate the modified program and understand the results. The programmer's information describes the option structure and logic enabling a programmer to make major revisions to this part of the TOLA computer program.
Programme Costing - A Logical Step Toward Improved Management.
ERIC Educational Resources Information Center
McDougall, Ronald N.
The analysis of costs of university activities from a functional or program point of view, rather than an organizational unit basis, is not only an imperative for the planning and management of universities, but also a logical method of examing the costs of university operations. A task force of the Committee of Finance Officers-Universities of…
An iLab for Teaching Advanced Logic Concepts with Hardware Descriptive Languages
ERIC Educational Resources Information Center
Ayodele, Kayode P.; Inyang, Isaac A.; Kehinde, Lawrence O.
2015-01-01
One of the more interesting approaches to teaching advanced logic concepts is the use of online laboratory frameworks to provide student access to remote field-programmable devices. There is as yet, however, no conclusive evidence of the effectiveness of such an approach. This paper presents the Advanced Digital Lab, a remote laboratory based on…
R-189 (C-620) air compressor control logic software documentation. Revision 1
DOE Office of Scientific and Technical Information (OSTI.GOV)
Walter, K.E.
1995-06-08
This relates to FFTF plant air compressors. Purpose of this document is to provide an updated Computer Software Description for the software to be used on R-189 (C-620-C) air compressor programmable controllers. Logic software design changes were required to allow automatic starting of a compressor that had not been previously started.
NASA Astrophysics Data System (ADS)
Zhang, X.; Wan, C. H.; Yuan, Z. H.; Fang, C.; Kong, W. J.; Wu, H.; Zhang, Q. T.; Tao, B. S.; Han, X. F.
2017-04-01
Confronting with the gigantic volume of data produced every day, raising integration density by reducing the size of devices becomes harder and harder to meet the ever-increasing demand for high-performance computers. One feasible path is to actualize more logic functions in one cell. In this respect, we experimentally demonstrate a prototype spin-orbit torque based spin logic cell integrated with five frequently used logic functions (AND, OR, NOT, NAND and NOR). The cell can be easily programmed and reprogrammed to perform desired function. Furthermore, the information stored in cells is symmetry-protected, making it possible to expand into logic gate array where the cell can be manipulated one by one without changing the information of other undesired cells. This work provides a prospective example of multi-functional spin logic cell with reprogrammability and nonvolatility, which will advance the application of spin logic devices.
NASA Astrophysics Data System (ADS)
Mclaughlin, Cheryl Althea
A professional learning community (PLC) typically consists of practitioners who systematically examine and problematize their practice with the intention of development and improvement. The collaborative practices inherent in PLCs mirror the way scientists work together to develop new theories, and are particularly valuable for science teachers who could draw from these experiences to improve the quality of student learning. Gaps in the science education literature support the need for research to determine how interactions within PLCs support science teacher development. Additionally, issues of power that may constrain or encourage meaningful interactions are largely overlooked in PLC studies. This qualitative study examines, from a Foucauldian perspective, interactions within a PLC comprising middle school science teachers preparing to implement reform curriculum. Specifically, the study analyzes interactions within the PLC to determine opportunities created for professional learning and development. Audiotaped transcripts of teacher interactions were analyzed using discourse analysis building tasks designed to identify opportunities for learning and to examine the exercise of power within the PLCs. The discourse analytical tools integrated theories of Gee (2011) and Foucault (1972), and were used to deconstruct and interrogate the data. The events were subsequently reconstructed through the lens of social constructivism and Foucault theories on power. The findings identified several processes emerging from the interactions that contributed to the negotiation of an understanding of the reform curriculum. These include reflection on practice, reorganization of cognitive structures, reinvention of practice, and refinement of instructional strategies. The findings also indicated that the exercise of power by entities both external to, and within the PLCs influenced the process of meaning negotiation among the science teachers. The consensus achieved by the teachers reflected knowledge constructed by science education discourses external to the PLC, which regulated understandings emerging from the interactions. Additionally, some teachers, through their actions, exercised power in ways that hindered rather than enhanced constructive dialogue in PLCs. The exercise of power by external institutions was nevertheless necessary to set the stage for the series of actions, the outcome of which facilitated constructive dialogue among science teachers who were implementing the reform curriculum.
Memristor-CMOS hybrid integrated circuits for reconfigurable logic.
Xia, Qiangfei; Robinett, Warren; Cumbie, Michael W; Banerjee, Neel; Cardinali, Thomas J; Yang, J Joshua; Wu, Wei; Li, Xuema; Tong, William M; Strukov, Dmitri B; Snider, Gregory S; Medeiros-Ribeiro, Gilberto; Williams, R Stanley
2009-10-01
Hybrid reconfigurable logic circuits were fabricated by integrating memristor-based crossbars onto a foundry-built CMOS (complementary metal-oxide-semiconductor) platform using nanoimprint lithography, as well as materials and processes that were compatible with the CMOS. Titanium dioxide thin-film memristors served as the configuration bits and switches in a data routing network and were connected to gate-level CMOS components that acted as logic elements, in a manner similar to a field programmable gate array. We analyzed the chips using a purpose-built testing system, and demonstrated the ability to configure individual devices, use them to wire up various logic gates and a flip-flop, and then reconfigure devices.
Peptide Logic Circuits Based on Chemoenzymatic Ligation for Programmable Cell Apoptosis.
Li, Yong; Sun, Sujuan; Fan, Lin; Hu, Shanfang; Huang, Yan; Zhang, Ke; Nie, Zhou; Yao, Shouzhou
2017-11-20
A novel and versatile peptide-based bio-logic system capable of regulating cell function is developed using sortase A (SrtA), a peptide ligation enzyme, as a generic processor. By modular peptide design, we demonstrate that mammalian cells apoptosis can be programmed by peptide-based logic operations, including binary and combination gates (AND, INHIBIT, OR, and AND-INHIBIT), and a complex sequential logic circuit (multi-input keypad lock). Moreover, a proof-of-concept peptide regulatory circuit was developed to analyze the expression profile of cell-secreted protein biomarkers and trigger cancer-cell-specific apoptosis. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.
Orbach, Ron; Willner, Bilha; Willner, Itamar
2015-03-11
This feature article addresses the implementation of catalytic nucleic acids as functional units for the construction of logic gates and computing circuits, and discusses the future applications of these systems. The assembly of computational modules composed of DNAzymes has led to the operation of a universal set of logic gates, to field programmable logic gates and computing circuits, to the development of multiplexers/demultiplexers, and to full-adder systems. Also, DNAzyme cascades operating as logic gates and computing circuits were demonstrated. DNAzyme logic systems find important practical applications. These include the use of DNAzyme-based systems for sensing and multiplexed analyses, for the development of controlled release and drug delivery systems, for regulating intracellular biosynthetic pathways, and for the programmed synthesis and operation of cascades.
Optimized 4-bit Quantum Reversible Arithmetic Logic Unit
NASA Astrophysics Data System (ADS)
Ayyoub, Slimani; Achour, Benslama
2017-08-01
Reversible logic has received a great attention in the recent years due to its ability to reduce the power dissipation. The main purposes of designing reversible logic are to decrease quantum cost, depth of the circuits and the number of garbage outputs. The arithmetic logic unit (ALU) is an important part of central processing unit (CPU) as the execution unit. This paper presents a complete design of a new reversible arithmetic logic unit (ALU) that can be part of a programmable reversible computing device such as a quantum computer. The proposed ALU based on a reversible low power control unit and small performance parameters full adder named double Peres gates. The presented ALU can produce the largest number (28) of arithmetic and logic functions and have the smallest number of quantum cost and delay compared with existing designs.
FPGA-based multiprocessor system for injection molding control.
Muñoz-Barron, Benigno; Morales-Velazquez, Luis; Romero-Troncoso, Rene J; Rodriguez-Donate, Carlos; Trejo-Hernandez, Miguel; Benitez-Rangel, Juan P; Osornio-Rios, Roque A
2012-10-18
The plastic industry is a very important manufacturing sector and injection molding is a widely used forming method in that industry. The contribution of this work is the development of a strategy to retrofit control of an injection molding machine based on an embedded system microprocessors sensor network on a field programmable gate array (FPGA) device. Six types of embedded processors are included in the system: a smart-sensor processor, a micro fuzzy logic controller, a programmable logic controller, a system manager, an IO processor and a communication processor. Temperature, pressure and position are controlled by the proposed system and experimentation results show its feasibility and robustness. As validation of the present work, a particular sample was successfully injected.
Raising a Programmer: Teaching Saudi Children How to Code
ERIC Educational Resources Information Center
Meccawy, Maram
2017-01-01
Teaching computer coding to children from a young age provides with them a competitive advantage for the future in a continually changing workplace. Programming strengthens logical and critical thinking as well as problem-solving skills, which lead to creative solutions for today's problems. The Little Programmer is an application for mobile…
Multiprog Virtual Laboratory Applied to PLC Programming Learning
ERIC Educational Resources Information Center
Shyr, Wen-Jye
2010-01-01
This study develops a Multiprog virtual laboratory for a mechatronics education designed to teach how to programme a programmable logic controller (PLC). The study was carried out with 34 students in the Department of Industry Education and Technology at National Changhua University of Education in Taiwan. In total, 17 students were assigned to…
Filling the Assurance Gap on Complex Electronics
NASA Technical Reports Server (NTRS)
Plastow, Richard A.
2007-01-01
Many of the methods used to develop software bare a close resemblance to Complex Electronics (CE) development. CE are now programmed to perform tasks that were previously handled by software, such as communication protocols. For example, the James Webb Space Telescope will use Field Programmable Gate Arrays (FPGAs), which can have over a million logic gates, to send telemetry. System-on-chip (SoC) devices, another type of complex electronics, can combine a microprocessor, input and output channels, and sometimes an FPGA for programmability. With this increased intricacy, the possibility of software-like bugs such as incorrect design, logic, and unexpected interactions within the logic is great. Since CE devices are obscuring the hardware/software boundary, mature software methodologies have been proposed, with slight modifications, to develop these devices. By using standardized S/W Engineering methods such as checklists, missing requirements and bugs can be detected earlier in the development cycle, thus creating a development process for CE that can be easily maintained and configurable based on the device used.
Software Process Assurance for Complex Electronics
NASA Technical Reports Server (NTRS)
Plastow, Richard A.
2007-01-01
Complex Electronics (CE) now perform tasks that were previously handled in software, such as communication protocols. Many methods used to develop software bare a close resemblance to CE development. Field Programmable Gate Arrays (FPGAs) can have over a million logic gates while system-on-chip (SOC) devices can combine a microprocessor, input and output channels, and sometimes an FPGA for programmability. With this increased intricacy, the possibility of software-like bugs such as incorrect design, logic, and unexpected interactions within the logic is great. With CE devices obscuring the hardware/software boundary, we propose that mature software methodologies may be utilized with slight modifications in the development of these devices. Software Process Assurance for Complex Electronics (SPACE) is a research project that used standardized S/W Assurance/Engineering practices to provide an assurance framework for development activities. Tools such as checklists, best practices and techniques were used to detect missing requirements and bugs earlier in the development cycle creating a development process for CE that was more easily maintained, consistent and configurable based on the device used.
Logic Design Pathology and Space Flight Electronics
NASA Technical Reports Server (NTRS)
Katz, Richard; Barto, Rod L.; Erickson, K.
1997-01-01
Logic design errors have been observed in space flight missions and the final stages of ground test. The technologies used by designers and their design/analysis methodologies will be analyzed. This will give insight to the root causes of the failures. These technologies include discrete integrated circuit based systems, systems based on field and mask programmable logic, and the use computer aided engineering (CAE) systems. State-of-the-art (SOTA) design tools and methodologies will be analyzed with respect to high-reliability spacecraft design and potential pitfalls are discussed. Case studies of faults from large expensive programs to "smaller, faster, cheaper" missions will be used to explore the fundamental reasons for logic design problems.
Interface For Dual-Channel MIL-STD-1553 Data Bus
NASA Technical Reports Server (NTRS)
Davies, Bryan L.; Heaps, Timothy L.
1992-01-01
Digital electronic subsystem made of commercially available programmable logic arrays and discrete logic devices serves as interface between microprocessor and dual-channel MIL-STD-1553 data bus. Subsystem consumes only 800 mW of power. Provides flexibility in that it is controllable via firmware. Includes only two reading-and-writing ports: one for status and control signals, other for transmission and reception of data.
Design and Implementation of an MC68020-Based Educational Computer Board
1989-12-01
device and the other for a Macintosh personal computer. A stored program can be installed in 8K bytes Programmable Read Only Memory (PROM) to initialize...MHz. It includes four * Static Random Access Memory (SRAM) chips which provide a storage of 32K bytes. Two Programmable Array Logic (PAL) chips...device and the other for a Macintosh personal computer. A stored program can be installed in 8K bytes Programmable Read Only Memory (PROM) to
Remote Control Laboratory Using EJS Applets and TwinCAT Programmable Logic Controllers
ERIC Educational Resources Information Center
Besada-Portas, E.; Lopez-Orozco, J. A.; de la Torre, L.; de la Cruz, J. M.
2013-01-01
This paper presents a new methodology to develop remote laboratories for systems engineering and automation control courses, based on the combined use of TwinCAT, a laboratory Java server application, and Easy Java Simulations (EJS). The TwinCAT system is used to close the control loop for the selected plants by means of programmable logic…
Toward Automating Web Protocol Configuration for a Programmable Logic Controller Emulator
2014-06-19
Security Risks for Industrial Control Systems ,” VDE 2004 Congress, Berlin, Germany, October 2004, pp. 1-7. [Cis12] Cisco, NetFlow Configuration Guide...Date 29 May 2014 Date AFIT-ENG-T-14-J-4 Abstract Industrial Control Systems (ICS) remain vulnerable through attack vectors that exist within programmable...5 2.2 Industrial Control Systems
Reconfigurable logic via gate controlled domain wall trajectory in magnetic network structure
Murapaka, C.; Sethi, P.; Goolaup, S.; Lew, W. S.
2016-01-01
An all-magnetic logic scheme has the advantages of being non-volatile and energy efficient over the conventional transistor based logic devices. In this work, we present a reconfigurable magnetic logic device which is capable of performing all basic logic operations in a single device. The device exploits the deterministic trajectory of domain wall (DW) in ferromagnetic asymmetric branch structure for obtaining different output combinations. The programmability of the device is achieved by using a current-controlled magnetic gate, which generates a local Oersted field. The field generated at the magnetic gate influences the trajectory of the DW within the structure by exploiting its inherent transverse charge distribution. DW transformation from vortex to transverse configuration close to the output branch plays a pivotal role in governing the DW chirality and hence the output. By simply switching the current direction through the magnetic gate, two universal logic gate functionalities can be obtained in this device. Using magnetic force microscopy imaging and magnetoresistance measurements, all basic logic functionalities are demonstrated. PMID:26839036
FPGA-Based Multiprocessor System for Injection Molding Control
Muñoz-Barron, Benigno; Morales-Velazquez, Luis; Romero-Troncoso, Rene J.; Rodriguez-Donate, Carlos; Trejo-Hernandez, Miguel; Benitez-Rangel, Juan P.; Osornio-Rios, Roque A.
2012-01-01
The plastic industry is a very important manufacturing sector and injection molding is a widely used forming method in that industry. The contribution of this work is the development of a strategy to retrofit control of an injection molding machine based on an embedded system microprocessors sensor network on a field programmable gate array (FPGA) device. Six types of embedded processors are included in the system: a smart-sensor processor, a micro fuzzy logic controller, a programmable logic controller, a system manager, an IO processor and a communication processor. Temperature, pressure and position are controlled by the proposed system and experimentation results show its feasibility and robustness. As validation of the present work, a particular sample was successfully injected. PMID:23202036
Two-dimensional non-volatile programmable p-n junctions
NASA Astrophysics Data System (ADS)
Li, Dong; Chen, Mingyuan; Sun, Zhengzong; Yu, Peng; Liu, Zheng; Ajayan, Pulickel M.; Zhang, Zengxing
2017-09-01
Semiconductor p-n junctions are the elementary building blocks of most electronic and optoelectronic devices. The need for their miniaturization has fuelled the rapid growth of interest in two-dimensional (2D) materials. However, the performance of a p-n junction considerably degrades as its thickness approaches a few nanometres and traditional technologies, such as doping and implantation, become invalid at the nanoscale. Here we report stable non-volatile programmable p-n junctions fabricated from the vertically stacked all-2D semiconductor/insulator/metal layers (WSe2/hexagonal boron nitride/graphene) in a semifloating gate field-effect transistor configuration. The junction exhibits a good rectifying behaviour with a rectification ratio of 104 and photovoltaic properties with a power conversion efficiency up to 4.1% under a 6.8 nW light. Based on the non-volatile programmable properties controlled by gate voltages, the 2D p-n junctions have been exploited for various electronic and optoelectronic applications, such as memories, photovoltaics, logic rectifiers and logic optoelectronic circuits.
Rodríguez, Manuel; Magdaleno, Eduardo; Pérez, Fernando; García, Cristhian
2017-03-28
Non-equispaced Fast Fourier transform (NFFT) is a very important algorithm in several technological and scientific areas such as synthetic aperture radar, computational photography, medical imaging, telecommunications, seismic analysis and so on. However, its computation complexity is high. In this paper, we describe an efficient NFFT implementation with a hardware coprocessor using an All-Programmable System-on-Chip (APSoC). This is a hybrid device that employs an Advanced RISC Machine (ARM) as Processing System with Programmable Logic for high-performance digital signal processing through parallelism and pipeline techniques. The algorithm has been coded in C language with pragma directives to optimize the architecture of the system. We have used the very novel Software Develop System-on-Chip (SDSoC) evelopment tool that simplifies the interface and partitioning between hardware and software. This provides shorter development cycles and iterative improvements by exploring several architectures of the global system. The computational results shows that hardware acceleration significantly outperformed the software based implementation.
Designed cell consortia as fragrance-programmable analog-to-digital converters.
Müller, Marius; Ausländer, Simon; Spinnler, Andrea; Ausländer, David; Sikorski, Julian; Folcher, Marc; Fussenegger, Martin
2017-03-01
Synthetic biology advances the rational engineering of mammalian cells to achieve cell-based therapy goals. Synthetic gene networks have nearly reached the complexity of digital electronic circuits and enable single cells to perform programmable arithmetic calculations or to provide dynamic remote control of transgenes through electromagnetic waves. We designed a synthetic multilayered gaseous-fragrance-programmable analog-to-digital converter (ADC) allowing for remote control of digital gene expression with 2-bit AND-, OR- and NOR-gate logic in synchronized cell consortia. The ADC consists of multiple sampling-and-quantization modules sensing analog gaseous fragrance inputs; a gas-to-liquid transducer converting fragrance intensity into diffusible cell-to-cell signaling compounds; a digitization unit with a genetic amplifier circuit to improve the signal-to-noise ratio; and recombinase-based digital expression switches enabling 2-bit processing of logic gates. Synthetic ADCs that can remotely control cellular activities with digital precision may enable the development of novel biosensors and may provide bioelectronic interfaces synchronizing analog metabolic pathways with digital electronics.
Rodríguez, Manuel; Magdaleno, Eduardo; Pérez, Fernando; García, Cristhian
2017-01-01
Non-equispaced Fast Fourier transform (NFFT) is a very important algorithm in several technological and scientific areas such as synthetic aperture radar, computational photography, medical imaging, telecommunications, seismic analysis and so on. However, its computation complexity is high. In this paper, we describe an efficient NFFT implementation with a hardware coprocessor using an All-Programmable System-on-Chip (APSoC). This is a hybrid device that employs an Advanced RISC Machine (ARM) as Processing System with Programmable Logic for high-performance digital signal processing through parallelism and pipeline techniques. The algorithm has been coded in C language with pragma directives to optimize the architecture of the system. We have used the very novel Software Develop System-on-Chip (SDSoC) evelopment tool that simplifies the interface and partitioning between hardware and software. This provides shorter development cycles and iterative improvements by exploring several architectures of the global system. The computational results shows that hardware acceleration significantly outperformed the software based implementation. PMID:28350358
Two-dimensional non-volatile programmable p-n junctions.
Li, Dong; Chen, Mingyuan; Sun, Zhengzong; Yu, Peng; Liu, Zheng; Ajayan, Pulickel M; Zhang, Zengxing
2017-09-01
Semiconductor p-n junctions are the elementary building blocks of most electronic and optoelectronic devices. The need for their miniaturization has fuelled the rapid growth of interest in two-dimensional (2D) materials. However, the performance of a p-n junction considerably degrades as its thickness approaches a few nanometres and traditional technologies, such as doping and implantation, become invalid at the nanoscale. Here we report stable non-volatile programmable p-n junctions fabricated from the vertically stacked all-2D semiconductor/insulator/metal layers (WSe 2 /hexagonal boron nitride/graphene) in a semifloating gate field-effect transistor configuration. The junction exhibits a good rectifying behaviour with a rectification ratio of 10 4 and photovoltaic properties with a power conversion efficiency up to 4.1% under a 6.8 nW light. Based on the non-volatile programmable properties controlled by gate voltages, the 2D p-n junctions have been exploited for various electronic and optoelectronic applications, such as memories, photovoltaics, logic rectifiers and logic optoelectronic circuits.
Assessing child and adolescent pragmatic language competencies: toward evidence-based assessments.
Russell, Robert L; Grizzle, Kenneth L
2008-06-01
Using language appropriately and effectively in social contexts requires pragmatic language competencies (PLCs). Increasingly, deficits in PLCs are linked to child and adolescent disorders, including autism spectrum, externalizing, and internalizing disorders. As the role of PLCs expands in diagnosis and treatment of developmental psychopathology, psychologists and educators will need to appraise and select clinical and research PLC instruments for use in assessments and/or studies. To assist in this appraisal, 24 PLC instruments, containing 1,082 items, are assessed by addressing four questions: (1) Can PLC domains targeted by assessment items be reliably identified?, (2) What are the core PLC domains that emerge across the 24 instruments?, (3) Do PLC questionnaires and tests assess similar PLC domains?, and (4) Do the instruments achieve content, structural, diagnostic, and ecological validity? Results indicate that test and questionnaire items can be reliably categorized into PLC domains, that PLC domains featured in questionnaires and tests significantly differ, and that PLC instruments need empirical confirmation of their dimensional structure, content validity across all developmental age bands, and ecological validity. Progress in building a better evidence base for PLC assessments should be a priority in future research.
Revisiting the role of phospholipases C in virulence and the lifecycle of Mycobacterium tuberculosis
Le Chevalier, Fabien; Cascioferro, Alessandro; Frigui, Wafa; Pawlik, Alexandre; Boritsch, Eva C.; Bottai, Daria; Majlessi, Laleh; Herrmann, Jean Louis; Brosch, Roland
2015-01-01
Mycobacterium tuberculosis, the agent of human tuberculosis has developed different virulence mechanisms and virulence-associated tools during its evolution to survive and multiply inside the host. Based on previous reports and by analogy with other bacteria, phospholipases C (PLC) of M. tuberculosis were thought to be among these tools. To get deeper insights into the function of PLCs, we investigated their putative involvement in the intracellular lifestyle of M. tuberculosis, with emphasis on phagosomal rupture and virulence, thereby re-visiting a research theme of longstanding interest. Through the construction and use of an M. tuberculosis H37Rv PLC-null mutant (ΔPLC) and control strains, we found that PLCs of M. tuberculosis were not required for induction of phagosomal rupture and only showed marginal, if any, impact on virulence of M. tuberculosis in the cellular and mouse infection models used in this study. In contrast, we found that PLC-encoding genes were strongly upregulated under phosphate starvation and that PLC-proficient M. tuberculosis strains survived better than ΔPLC mutants under conditions where phosphatidylcholine served as sole phosphate source, opening new perspectives for studies on the role of PLCs in the lifecycle of M. tuberculosis. PMID:26603639
Catalytic molecular logic devices by DNAzyme displacement.
Brown, Carl W; Lakin, Matthew R; Stefanovic, Darko; Graves, Steven W
2014-05-05
Chemical reactions catalyzed by DNAzymes offer a route to programmable modification of biomolecules for therapeutic purposes. To this end, we have developed a new type of catalytic DNA-based logic gates in which DNAzyme catalysis is controlled via toehold-mediated strand displacement reactions. We refer to these as DNAzyme displacement gates. The use of toeholds to guide input binding provides a favorable pathway for input recognition, and the innate catalytic activity of DNAzymes allows amplification of nanomolar input concentrations. We demonstrate detection of arbitrary input sequences by rational introduction of mismatched bases into inhibitor strands. Furthermore, we illustrate the applicability of DNAzyme displacement to compute logic functions involving multiple logic gates. This work will enable sophisticated logical control of a range of biochemical modifications, with applications in pathogen detection and autonomous theranostics. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Programmable full-adder computations in communicating three-dimensional cell cultures.
Ausländer, David; Ausländer, Simon; Pierrat, Xavier; Hellmann, Leon; Rachid, Leila; Fussenegger, Martin
2018-01-01
Synthetic biologists have advanced the design of trigger-inducible gene switches and their assembly into input-programmable circuits that enable engineered human cells to perform arithmetic calculations reminiscent of electronic circuits. By designing a versatile plug-and-play molecular-computation platform, we have engineered nine different cell populations with genetic programs, each of which encodes a defined computational instruction. When assembled into 3D cultures, these engineered cell consortia execute programmable multicellular full-adder logics in response to three trigger compounds.
A Survey of Memristive Threshold Logic Circuits.
Maan, Akshay Kumar; Jayadevi, Deepthi Anirudhan; James, Alex Pappachen
2017-08-01
In this paper, we review different memristive threshold logic (MTL) circuits that are inspired from the synaptic action of the flow of neurotransmitters in the biological brain. The brainlike generalization ability and the area minimization of these threshold logic circuits aim toward crossing Moore's law boundaries at device, circuits, and systems levels. Fast switching memory, signal processing, control systems, programmable logic, image processing, reconfigurable computing, and pattern recognition are identified as some of the potential applications of MTL systems. The physical realization of nanoscale devices with memristive behavior from materials, such as TiO 2 , ferroelectrics, silicon, and polymers, has accelerated research effort in these application areas, inspiring the scientific community to pursue the design of high-speed, low-cost, low-power, and high-density neuromorphic architectures.
All-spin logic operations: Memory device and reconfigurable computing
NASA Astrophysics Data System (ADS)
Patra, Moumita; Maiti, Santanu K.
2018-02-01
Exploiting spin degree of freedom of electron a new proposal is given to characterize spin-based logical operations using a quantum interferometer that can be utilized as a programmable spin logic device (PSLD). The ON and OFF states of both inputs and outputs are described by spin state only, circumventing spin-to-charge conversion at every stage as often used in conventional devices with the inclusion of extra hardware that can eventually diminish the efficiency. All possible logic functions can be engineered from a single device without redesigning the circuit which certainly offers the opportunities of designing new generation spintronic devices. Moreover, we also discuss the utilization of the present model as a memory device and suitable computing operations with proposed experimental setups.
OpenFlow Extensions for Programmable Quantum Networks
2017-06-19
Extensions for Programmable Quantum Networks by Venkat Dasari, Nikolai Snow, and Billy Geerhart Computational and Information Sciences Directorate...distribution is unlimited. 1 1. Introduction Quantum networks and quantum computing have been receiving a surge of interest recently.1–3 However, there has...communicate using entangled particles and perform calculations using quantum logic gates. Additionally, quantum computing uses a quantum bit (qubit
Programmable logic controller performance enhancement by field programmable gate array based design.
Patel, Dhruv; Bhatt, Jignesh; Trivedi, Sanjay
2015-01-01
PLC, the core element of modern automation systems, due to serial execution, exhibits limitations like slow speed and poor scan time. Improved PLC design using FPGA has been proposed based on parallel execution mechanism for enhancement of performance and flexibility. Modelsim as simulation platform and VHDL used to translate, integrate and implement the logic circuit in FPGA. Xilinx's Spartan kit for implementation-testing and VB has been used for GUI development. Salient merits of the design include cost-effectiveness, miniaturization, user-friendliness, simplicity, along with lower power consumption, smaller scan time and higher speed. Various functionalities and applications like typical PLC and industrial alarm annunciator have been developed and successfully tested. Results of simulation, design and implementation have been reported. Copyright © 2014 ISA. Published by Elsevier Ltd. All rights reserved.
Failure detection in high-performance clusters and computers using chaotic map computations
Rao, Nageswara S.
2015-09-01
A programmable media includes a processing unit capable of independent operation in a machine that is capable of executing 10.sup.18 floating point operations per second. The processing unit is in communication with a memory element and an interconnect that couples computing nodes. The programmable media includes a logical unit configured to execute arithmetic functions, comparative functions, and/or logical functions. The processing unit is configured to detect computing component failures, memory element failures and/or interconnect failures by executing programming threads that generate one or more chaotic map trajectories. The central processing unit or graphical processing unit is configured to detect a computing component failure, memory element failure and/or an interconnect failure through an automated comparison of signal trajectories generated by the chaotic maps.
Software Process Assurance for Complex Electronics (SPACE)
NASA Technical Reports Server (NTRS)
Plastow, Richard A.
2007-01-01
Complex Electronics (CE) are now programmed to perform tasks that were previously handled in software, such as communication protocols. Many of the methods used to develop software bare a close resemblance to CE development. For instance, Field Programmable Gate Arrays (FPGAs) can have over a million logic gates while system-on-chip (SOC) devices can combine a microprocessor, input and output channels, and sometimes an FPGA for programmability. With this increased intricacy, the possibility of software-like bugs such as incorrect design, logic, and unexpected interactions within the logic is great. Since CE devices are obscuring the hardware/software boundary, we propose that mature software methodologies may be utilized with slight modifications in the development of these devices. Software Process Assurance for Complex Electronics (SPACE) is a research project that looks at using standardized S/W Assurance/Engineering practices to provide an assurance framework for development activities. Tools such as checklists, best practices and techniques can be used to detect missing requirements and bugs earlier in the development cycle creating a development process for CE that will be more easily maintained, consistent and configurable based on the device used.
Programmable computing with a single magnetoresistive element
NASA Astrophysics Data System (ADS)
Ney, A.; Pampuch, C.; Koch, R.; Ploog, K. H.
2003-10-01
The development of transistor-based integrated circuits for modern computing is a story of great success. However, the proved concept for enhancing computational power by continuous miniaturization is approaching its fundamental limits. Alternative approaches consider logic elements that are reconfigurable at run-time to overcome the rigid architecture of the present hardware systems. Implementation of parallel algorithms on such `chameleon' processors has the potential to yield a dramatic increase of computational speed, competitive with that of supercomputers. Owing to their functional flexibility, `chameleon' processors can be readily optimized with respect to any computer application. In conventional microprocessors, information must be transferred to a memory to prevent it from getting lost, because electrically processed information is volatile. Therefore the computational performance can be improved if the logic gate is additionally capable of storing the output. Here we describe a simple hardware concept for a programmable logic element that is based on a single magnetic random access memory (MRAM) cell. It combines the inherent advantage of a non-volatile output with flexible functionality which can be selected at run-time to operate as an AND, OR, NAND or NOR gate.
Non-volatile logic gates based on planar Hall effect in magnetic films with two in-plane easy axes.
Lee, Sangyeop; Bac, Seul-Ki; Choi, Seonghoon; Lee, Hakjoon; Yoo, Taehee; Lee, Sanghoon; Liu, Xinyu; Dobrowolska, M; Furdyna, Jacek K
2017-04-25
We discuss the use of planar Hall effect (PHE) in a ferromagnetic GaMnAs film with two in-plane easy axes as a means for achieving novel logic functionalities. We show that the switching of magnetization between the easy axes in a GaMnAs film depends strongly on the magnitude of the current flowing through the film due to thermal effects that modify its magnetic anisotropy. Planar Hall resistance in a GaMnAs film with two in-plane easy axes shows well-defined maxima and minima that can serve as two binary logic states. By choosing appropriate magnitudes of the input current for the GaMnAs Hall device, magnetic logic functions can then be achieved. Specifically, non-volatile logic functionalities such as AND, OR, NAND, and NOR gates can be obtained in such a device by selecting appropriate initial conditions. These results, involving a simple PHE device, hold promise for realizing programmable logic elements in magnetic electronics.
Simultaneous G-Quadruplex DNA Logic.
Bader, Antoine; Cockroft, Scott L
2018-04-03
A fundamental principle of digital computer operation is Boolean logic, where inputs and outputs are described by binary integer voltages. Similarly, inputs and outputs may be processed on the molecular level as exemplified by synthetic circuits that exploit the programmability of DNA base-pairing. Unlike modern computers, which execute large numbers of logic gates in parallel, most implementations of molecular logic have been limited to single computing tasks, or sensing applications. This work reports three G-quadruplex-based logic gates that operate simultaneously in a single reaction vessel. The gates respond to unique Boolean DNA inputs by undergoing topological conversion from duplex to G-quadruplex states that were resolved using a thioflavin T dye and gel electrophoresis. The modular, addressable, and label-free approach could be incorporated into DNA-based sensors, or used for resolving and debugging parallel processes in DNA computing applications. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.
FPGA-based gating and logic for multichannel single photon counting
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pooser, Raphael C; Earl, Dennis Duncan; Evans, Philip G
2012-01-01
We present results characterizing multichannel InGaAs single photon detectors utilizing gated passive quenching circuits (GPQC), self-differencing techniques, and field programmable gate array (FPGA)-based logic for both diode gating and coincidence counting. Utilizing FPGAs for the diode gating frontend and the logic counting backend has the advantage of low cost compared to custom built logic circuits and current off-the-shelf detector technology. Further, FPGA logic counters have been shown to work well in quantum key distribution (QKD) test beds. Our setup combines multiple independent detector channels in a reconfigurable manner via an FPGA backend and post processing in order to perform coincidencemore » measurements between any two or more detector channels simultaneously. Using this method, states from a multi-photon polarization entangled source are detected and characterized via coincidence counting on the FPGA. Photons detection events are also processed by the quantum information toolkit for application testing (QITKAT)« less
46 CFR 62.20-1 - Plans for approval.
Code of Federal Regulations, 2014 CFR
2014-10-01
... console, panel, and enclosure layouts. (3) Schematic or logic diagrams including functional relationships... programmable features. (6) A description of built-in test features and diagnostics. (7) Design Verification and...
Gao, Jinting; Liu, Yaqing; Lin, Xiaodong; Deng, Jiankang; Yin, Jinjin; Wang, Shuo
2017-10-25
Wiring a series of simple logic gates to process complex data is significantly important and a large challenge for untraditional molecular computing systems. The programmable property of DNA endows its powerful application in molecular computing. In our investigation, it was found that DNA exhibits excellent peroxidase-like activity in a colorimetric system of TMB/H 2 O 2 /Hemin (TMB, 3,3', 5,5'-Tetramethylbenzidine) in the presence of K + and Cu 2+ , which is significantly inhibited by the addition of an antioxidant. According to the modulated catalytic activity of this DNA-based catalyst, three cascade logic gates including AND-OR-INH (INHIBIT), AND-INH and OR-INH were successfully constructed. Interestingly, by only modulating the concentration of Cu 2+ , a majority logic gate with a single-vote veto function was realized following the same threshold value as that of the cascade logic gates. The strategy is quite straightforward and versatile and provides an instructive method for constructing multiple logic gates on a simple platform to implement complex molecular computing.
Graphene-based aptamer logic gates and their application to multiplex detection.
Wang, Li; Zhu, Jinbo; Han, Lei; Jin, Lihua; Zhu, Chengzhou; Wang, Erkang; Dong, Shaojun
2012-08-28
In this work, a GO/aptamer system was constructed to create multiplex logic operations and enable sensing of multiplex targets. 6-Carboxyfluorescein (FAM)-labeled adenosine triphosphate binding aptamer (ABA) and FAM-labeled thrombin binding aptamer (TBA) were first adsorbed onto graphene oxide (GO) to form a GO/aptamer complex, leading to the quenching of the fluorescence of FAM. We demonstrated that the unique GO/aptamer interaction and the specific aptamer-target recognition in the target/GO/aptamer system were programmable and could be utilized to regulate the fluorescence of FAM via OR and INHIBIT logic gates. The fluorescence changed according to different input combinations, and the integration of OR and INHIBIT logic gates provided an interesting approach for logic sensing applications where multiple target molecules were present. High-throughput fluorescence imagings that enabled the simultaneous processing of many samples by using the combinatorial logic gates were realized. The developed logic gates may find applications in further development of DNA circuits and advanced sensors for the identification of multiple targets in complex chemical environments.
Analysis of data throughput in communication between PLCs and HMI/SCADA systems
NASA Astrophysics Data System (ADS)
Mikolajek, Martin; Koziorek, Jiri
2016-09-01
This paper is focused on Analysis of data throughout in communication between PLCs and HMI/SCADA systems. The first part of paper discusses basic problematic communication between PLC and HMI systems. Next part is about specific types of communications PLC - HMI requests. For those cases paper is talking about response and data throughput1-3 . Subsequent section of this article contains practical parts with various data exchanges between PLC Siemens and HMI. The possibilities of communication that are described in this article are focused on using OPC server for visualization software, custom HMI system and own application created by using .NET with Technology. The last part of this article contains some communication solutions.
Enhancing Self-Efficacy in Elementary Science Teaching With Professional Learning Communities
NASA Astrophysics Data System (ADS)
Mintzes, Joel J.; Marcum, Bev; Messerschmidt-Yates, Christl; Mark, Andrew
2013-11-01
Emerging from Bandura's Social Learning Theory, this study of in-service elementary school teachers examined the effects of sustained Professional Learning Communities (PLCs) on self-efficacy in science teaching. Based on mixed research methods, and a non-equivalent control group experimental design, the investigation explored changes in personal self-efficacy and outcome expectancy among teachers engaged in PLCs that featured Demonstration Laboratories, Lesson Study, and annual Summer Institutes. Significant changes favoring the experimental group were found on all quantitative measures of self-efficacy. Structured clinical interviews revealed that observed changes were largely attributable to a wide range of direct (mastery) and vicarious experiences, as well as emotional reinforcement and social persuasion.
Nonlinear dynamics based digital logic and circuits.
Kia, Behnam; Lindner, John F; Ditto, William L
2015-01-01
We discuss the role and importance of dynamics in the brain and biological neural networks and argue that dynamics is one of the main missing elements in conventional Boolean logic and circuits. We summarize a simple dynamics based computing method, and categorize different techniques that we have introduced to realize logic, functionality, and programmability. We discuss the role and importance of coupled dynamics in networks of biological excitable cells, and then review our simple coupled dynamics based method for computing. In this paper, for the first time, we show how dynamics can be used and programmed to implement computation in any given base, including but not limited to base two.
Extended Logic Intelligent Processing System for a Sensor Fusion Processor Hardware
NASA Technical Reports Server (NTRS)
Stoica, Adrian; Thomas, Tyson; Li, Wei-Te; Daud, Taher; Fabunmi, James
2000-01-01
The paper presents the hardware implementation and initial tests from a low-power, highspeed reconfigurable sensor fusion processor. The Extended Logic Intelligent Processing System (ELIPS) is described, which combines rule-based systems, fuzzy logic, and neural networks to achieve parallel fusion of sensor signals in compact low power VLSI. The development of the ELIPS concept is being done to demonstrate the interceptor functionality which particularly underlines the high speed and low power requirements. The hardware programmability allows the processor to reconfigure into different machines, taking the most efficient hardware implementation during each phase of information processing. Processing speeds of microseconds have been demonstrated using our test hardware.
Current Radiation Issues for Programmable Elements and Devices
NASA Technical Reports Server (NTRS)
Katz, R.; Wang, J. J.; Koga, R.; LaBel, A.; McCollum, J.; Brown, R.; Reed, R. A.; Cronquist, B.; Crain, S.; Scott, T.;
1998-01-01
State of the an programmable devices are utilizing advanced processing technologies, non-standard circuit structures, and unique electrical elements in commercial-off-the-shelf (COTS)-based, high-performance devices. This paper will discuss that the above factors, coupled with the systems application environment, have a strong interplay that affect the radiation hardness of programmable devices and have resultant system impacts in (1) reliability of the unprogrammed, biased antifuse for heavy ions (rupture), (2) logic upset manifesting itself as clock upset, and (3) configuration upset. General radiation characteristics of advanced technologies are examined and manufacturers' modifications to their COTS-based and their impact on future programmable devices will be analyzed.
NASA Astrophysics Data System (ADS)
Liao, Fadian; Ruan, Qiuyong; Lin, Juqiang; Lin, Jinyong; Zeng, Yongyi; Li, Ling; Huang, Zufang; Liu, Nenrong; Chen, Rong
2014-09-01
Despite the introduction of high-technology methods of detection and diagnosis, screening of primary liver cancer (PLC) remains imperfect. To diagnosis PLC earlier, Surface-enhanced Raman spectroscopy (SERS) coupled with cellulose-acetate membrane electrophoresis were introduced to separate human serum albumin and SERS spectra. Three groups (15 normal persons' samples, 17 hepatitis/cirrhosis samples, 15 cases of PLC) of serum albumin were tested. Silver colloid was used to obtain SERS spectra of human serum albumin. Principal component analysis (PCA) and linear discriminant analysis (LDA) were also employed for statistical analysis. The mean Raman spectra of three groups and the difference spectra of any two suggested that the albumin has changed in liver patients. Compared to normal groups, some Raman peaks have shifted or even disappeared in hepatitis/cirrhosis and PLCs groups. The sensitivity and specificity between PLCs and normal groups is 80% and 93.3%. Among hepatitis/cirrhosis and normal groups, the sensitivity is 88.2% and specificity is also 93.3%. Besides, the sensitivity and specificity between PLCs and hepatitis/cirrhosis groups is 86.7% and 76.5%. All the above data and results indicated that early screening of PLC is potential by SERS in different stages of liver disease before cancer occurs.
Automated ILA design for synchronous sequential circuits
NASA Technical Reports Server (NTRS)
Liu, M. N.; Liu, K. Z.; Maki, G. K.; Whitaker, S. R.
1991-01-01
An iterative logic array (ILA) architecture for synchronous sequential circuits is presented. This technique utilizes linear algebra to produce the design equations. The ILA realization of synchronous sequential logic can be fully automated with a computer program. A programmable design procedure is proposed to fullfill the design task and layout generation. A software algorithm in the C language has been developed and tested to generate 1 micron CMOS layouts using the Hewlett-Packard FUNGEN module generator shell.
Molano, Eddy Patricia Lopez; Cabrera, Odalys García; Jose, Juliana; do Nascimento, Leandro Costa; Carazzolle, Marcelo Falsarella; Teixeira, Paulo José Pereira Lima; Alvarez, Javier Correa; Tiburcio, Ricardo Augusto; Tokimatu Filho, Paulo Massanari; de Lima, Gustavo Machado Alvares; Guido, Rafael Victório Carvalho; Corrêa, Thamy Lívia Ribeiro; Leme, Adriana Franco Paes; Mieczkowski, Piotr; Pereira, Gonçalo Amarante Guimarães
2018-01-17
The Ceratocystis genus harbors a large number of phytopathogenic fungi that cause xylem parenchyma degradation and vascular destruction on a broad range of economically important plants. Ceratocystis cacaofunesta is a necrotrophic fungus responsible for lethal wilt disease in cacao. The aim of this work is to analyze the genome of C. cacaofunesta through a comparative approach with genomes of other Sordariomycetes in order to better understand the molecular basis of pathogenicity in the Ceratocystis genus. We present an analysis of the C. cacaofunesta genome focusing on secreted proteins that might constitute pathogenicity factors. Comparative genome analyses among five Ceratocystidaceae species and 23 other Sordariomycetes fungi showed a strong reduction in gene content of the Ceratocystis genus. However, some gene families displayed a remarkable expansion, in particular, the Phosphatidylinositol specific phospholipases-C (PI-PLC) family. Also, evolutionary rate calculations suggest that the evolution process of this family was guided by positive selection. Interestingly, among the 82 PI-PLCs genes identified in the C. cacaofunesta genome, 70 genes encoding extracellular PI-PLCs are grouped in eight small scaffolds surrounded by transposon fragments and scars that could be involved in the rapid evolution of the PI-PLC family. Experimental secretome using LC-MS/MS validated 24% (86 proteins) of the total predicted secretome (342 proteins), including four PI-PLCs and other important pathogenicity factors. Analysis of the Ceratocystis cacaofunesta genome provides evidence that PI-PLCs may play a role in pathogenicity. Subsequent functional studies will be aimed at evaluating this hypothesis. The observed genetic arsenals, together with the analysis of the PI-PLC family shown in this work, reveal significant differences in the Ceratocystis genome compared to the classical vascular fungi, Verticillium and Fusarium. Altogether, our analyses provide new insights into the evolution and the molecular basis of plant pathogenicity.
Nanowire nanocomputer as a finite-state machine.
Yao, Jun; Yan, Hao; Das, Shamik; Klemic, James F; Ellenbogen, James C; Lieber, Charles M
2014-02-18
Implementation of complex computer circuits assembled from the bottom up and integrated on the nanometer scale has long been a goal of electronics research. It requires a design and fabrication strategy that can address individual nanometer-scale electronic devices, while enabling large-scale assembly of those devices into highly organized, integrated computational circuits. We describe how such a strategy has led to the design, construction, and demonstration of a nanoelectronic finite-state machine. The system was fabricated using a design-oriented approach enabled by a deterministic, bottom-up assembly process that does not require individual nanowire registration. This methodology allowed construction of the nanoelectronic finite-state machine through modular design using a multitile architecture. Each tile/module consists of two interconnected crossbar nanowire arrays, with each cross-point consisting of a programmable nanowire transistor node. The nanoelectronic finite-state machine integrates 180 programmable nanowire transistor nodes in three tiles or six total crossbar arrays, and incorporates both sequential and arithmetic logic, with extensive intertile and intratile communication that exhibits rigorous input/output matching. Our system realizes the complete 2-bit logic flow and clocked control over state registration that are required for a finite-state machine or computer. The programmable multitile circuit was also reprogrammed to a functionally distinct 2-bit full adder with 32-set matched and complete logic output. These steps forward and the ability of our unique design-oriented deterministic methodology to yield more extensive multitile systems suggest that proposed general-purpose nanocomputers can be realized in the near future.
Nanowire nanocomputer as a finite-state machine
Yao, Jun; Yan, Hao; Das, Shamik; Klemic, James F.; Ellenbogen, James C.; Lieber, Charles M.
2014-01-01
Implementation of complex computer circuits assembled from the bottom up and integrated on the nanometer scale has long been a goal of electronics research. It requires a design and fabrication strategy that can address individual nanometer-scale electronic devices, while enabling large-scale assembly of those devices into highly organized, integrated computational circuits. We describe how such a strategy has led to the design, construction, and demonstration of a nanoelectronic finite-state machine. The system was fabricated using a design-oriented approach enabled by a deterministic, bottom–up assembly process that does not require individual nanowire registration. This methodology allowed construction of the nanoelectronic finite-state machine through modular design using a multitile architecture. Each tile/module consists of two interconnected crossbar nanowire arrays, with each cross-point consisting of a programmable nanowire transistor node. The nanoelectronic finite-state machine integrates 180 programmable nanowire transistor nodes in three tiles or six total crossbar arrays, and incorporates both sequential and arithmetic logic, with extensive intertile and intratile communication that exhibits rigorous input/output matching. Our system realizes the complete 2-bit logic flow and clocked control over state registration that are required for a finite-state machine or computer. The programmable multitile circuit was also reprogrammed to a functionally distinct 2-bit full adder with 32-set matched and complete logic output. These steps forward and the ability of our unique design-oriented deterministic methodology to yield more extensive multitile systems suggest that proposed general-purpose nanocomputers can be realized in the near future. PMID:24469812
2005-12-01
Upsets in SRAM FPGAs,” Military and Aerospace Applications of Programmable Logic Devices, September 2002. 8. Wakerly , John F,. “Microcomputer...change. The goal of the Configurable Fault Tolerant Processor (CFTP) Project is to explore, develop and demonstrate the applicability of using off-the...develop and demonstrate the applicability of using commercial-of-the-shelf (COTS) Field Programmable Gate Arrays (FPGA) in the design of
Nanopore Logic Operation with DNA to RNA Transcription in a Droplet System.
Ohara, Masayuki; Takinoue, Masahiro; Kawano, Ryuji
2017-07-21
This paper describes an AND logic operation with amplification and transcription from DNA to RNA, using T7 RNA polymerase. All four operations, (0 0) to (1 1), with an enzyme reaction can be performed simultaneously, using four-droplet devices that are directly connected to a patch-clamp amplifier. The output RNA molecule is detected using a biological nanopore with single-molecule translocation. Channel current recordings can be obtained using the enzyme solution. The integration of DNA logic gates into electrochemical devices is necessary to obtain output information in a human-recognizable form. Our method will be useful for rapid and confined DNA computing applications, including the development of programmable diagnostic devices.
NASA Astrophysics Data System (ADS)
Zheng, Bowen; Xu, Jun
2017-11-01
Mechanical information processing and control has attracted great attention in recent years. A challenging pursuit is to achieve broad functioning frequency ranges, especially at low-frequency domain. Here, we propose a design of mechanical logic switches based on DNA-inspired chiral acoustic metamaterials, which are capable of having ultrabroad band gaps at low-frequency domain. Logic operations can be easily performed by applying constraints at different locations and the functioning frequency ranges are able to be low, broad and tunable. This work may have an impact on the development of mechanical information processing, programmable materials, stress wave manipulation, as well as the isolation of noise and harmful vibration.
Programmable single-cell mammalian biocomputers.
Ausländer, Simon; Ausländer, David; Müller, Marius; Wieland, Markus; Fussenegger, Martin
2012-07-05
Synthetic biology has advanced the design of standardized control devices that program cellular functions and metabolic activities in living organisms. Rational interconnection of these synthetic switches resulted in increasingly complex designer networks that execute input-triggered genetic instructions with precision, robustness and computational logic reminiscent of electronic circuits. Using trigger-controlled transcription factors, which independently control gene expression, and RNA-binding proteins that inhibit the translation of transcripts harbouring specific RNA target motifs, we have designed a set of synthetic transcription–translation control devices that could be rewired in a plug-and-play manner. Here we show that these combinatorial circuits integrated a two-molecule input and performed digital computations with NOT, AND, NAND and N-IMPLY expression logic in single mammalian cells. Functional interconnection of two N-IMPLY variants resulted in bitwise intracellular XOR operations, and a combinatorial arrangement of three logic gates enabled independent cells to perform programmable half-subtractor and half-adder calculations. Individual mammalian cells capable of executing basic molecular arithmetic functions isolated or coordinated to metabolic activities in a predictable, precise and robust manner may provide new treatment strategies and bio-electronic interfaces in future gene-based and cell-based therapies.
Optically programmable encoder based on light propagation in two-dimensional regular nanoplates.
Li, Ya; Zhao, Fangyin; Guo, Shuai; Zhang, Yongyou; Niu, Chunhui; Zeng, Ruosheng; Zou, Bingsuo; Zhang, Wensheng; Ding, Kang; Bukhtiar, Arfan; Liu, Ruibin
2017-04-07
We design an efficient optically controlled microdevice based on CdSe nanoplates. Two-dimensional CdSe nanoplates exhibit lighting patterns around the edges and can be realized as a new type of optically controlled programmable encoder. The light source is used to excite the nanoplates and control the logical position under vertical pumping mode by the objective lens. At each excitation point in the nanoplates, the preferred light-propagation routes are along the normal direction and perpendicular to the edges, which then emit out from the edges to form a localized lighting section. The intensity distribution around the edges of different nanoplates demonstrates that the lighting part with a small scale is much stronger, defined as '1', than the dark section, defined as '0', along the edge. These '0' and '1' are the basic logic elements needed to compose logically functional devices. The observed propagation rules are consistent with theoretical simulations, meaning that the guided-light route in two-dimensional semiconductor nanoplates is regular and predictable. The same situation was also observed in regular CdS nanoplates. Basic theoretical analysis and experiments prove that the guided light and exit position follow rules mainly originating from the shape rather than material itself.
Programmable Potentials: Approximate N-body potentials from coarse-level logic.
Thakur, Gunjan S; Mohr, Ryan; Mezić, Igor
2016-09-27
This paper gives a systematic method for constructing an N-body potential, approximating the true potential, that accurately captures meso-scale behavior of the chemical or biological system using pairwise potentials coming from experimental data or ab initio methods. The meso-scale behavior is translated into logic rules for the dynamics. Each pairwise potential has an associated logic function that is constructed using the logic rules, a class of elementary logic functions, and AND, OR, and NOT gates. The effect of each logic function is to turn its associated potential on and off. The N-body potential is constructed as linear combination of the pairwise potentials, where the "coefficients" of the potentials are smoothed versions of the associated logic functions. These potentials allow a potentially low-dimensional description of complex processes while still accurately capturing the relevant physics at the meso-scale. We present the proposed formalism to construct coarse-grained potential models for three examples: an inhibitor molecular system, bond breaking in chemical reactions, and DNA transcription from biology. The method can potentially be used in reverse for design of molecular processes by specifying properties of molecules that can carry them out.
Programmable Potentials: Approximate N-body potentials from coarse-level logic
NASA Astrophysics Data System (ADS)
Thakur, Gunjan S.; Mohr, Ryan; Mezić, Igor
2016-09-01
This paper gives a systematic method for constructing an N-body potential, approximating the true potential, that accurately captures meso-scale behavior of the chemical or biological system using pairwise potentials coming from experimental data or ab initio methods. The meso-scale behavior is translated into logic rules for the dynamics. Each pairwise potential has an associated logic function that is constructed using the logic rules, a class of elementary logic functions, and AND, OR, and NOT gates. The effect of each logic function is to turn its associated potential on and off. The N-body potential is constructed as linear combination of the pairwise potentials, where the “coefficients” of the potentials are smoothed versions of the associated logic functions. These potentials allow a potentially low-dimensional description of complex processes while still accurately capturing the relevant physics at the meso-scale. We present the proposed formalism to construct coarse-grained potential models for three examples: an inhibitor molecular system, bond breaking in chemical reactions, and DNA transcription from biology. The method can potentially be used in reverse for design of molecular processes by specifying properties of molecules that can carry them out.
Programmable Potentials: Approximate N-body potentials from coarse-level logic
Thakur, Gunjan S.; Mohr, Ryan; Mezić, Igor
2016-01-01
This paper gives a systematic method for constructing an N-body potential, approximating the true potential, that accurately captures meso-scale behavior of the chemical or biological system using pairwise potentials coming from experimental data or ab initio methods. The meso-scale behavior is translated into logic rules for the dynamics. Each pairwise potential has an associated logic function that is constructed using the logic rules, a class of elementary logic functions, and AND, OR, and NOT gates. The effect of each logic function is to turn its associated potential on and off. The N-body potential is constructed as linear combination of the pairwise potentials, where the “coefficients” of the potentials are smoothed versions of the associated logic functions. These potentials allow a potentially low-dimensional description of complex processes while still accurately capturing the relevant physics at the meso-scale. We present the proposed formalism to construct coarse-grained potential models for three examples: an inhibitor molecular system, bond breaking in chemical reactions, and DNA transcription from biology. The method can potentially be used in reverse for design of molecular processes by specifying properties of molecules that can carry them out. PMID:27671683
Interlocked DNA nanostructures controlled by a reversible logic circuit.
Li, Tao; Lohmann, Finn; Famulok, Michael
2014-09-17
DNA nanostructures constitute attractive devices for logic computing and nanomechanics. An emerging interest is to integrate these two fields and devise intelligent DNA nanorobots. Here we report a reversible logic circuit built on the programmable assembly of a double-stranded (ds) DNA [3]pseudocatenane that serves as a rigid scaffold to position two separate branched-out head-motifs, a bimolecular i-motif and a G-quadruplex. The G-quadruplex only forms when preceded by the assembly of the i-motif. The formation of the latter, in turn, requires acidic pH and unhindered mobility of the head-motif containing dsDNA nanorings with respect to the central ring to which they are interlocked, triggered by release oligodeoxynucleotides. We employ these features to convert the structural changes into Boolean operations with fluorescence labelling. The nanostructure behaves as a reversible logic circuit consisting of tandem YES and AND gates. Such reversible logic circuits integrated into functional nanodevices may guide future intelligent DNA nanorobots to manipulate cascade reactions in biological systems.
Interlocked DNA nanostructures controlled by a reversible logic circuit
Li, Tao; Lohmann, Finn; Famulok, Michael
2014-01-01
DNA nanostructures constitute attractive devices for logic computing and nanomechanics. An emerging interest is to integrate these two fields and devise intelligent DNA nanorobots. Here we report a reversible logic circuit built on the programmable assembly of a double-stranded (ds) DNA [3]pseudocatenane that serves as a rigid scaffold to position two separate branched-out head-motifs, a bimolecular i-motif and a G-quadruplex. The G-quadruplex only forms when preceded by the assembly of the i-motif. The formation of the latter, in turn, requires acidic pH and unhindered mobility of the head-motif containing dsDNA nanorings with respect to the central ring to which they are interlocked, triggered by release oligodeoxynucleotides. We employ these features to convert the structural changes into Boolean operations with fluorescence labelling. The nanostructure behaves as a reversible logic circuit consisting of tandem YES and AND gates. Such reversible logic circuits integrated into functional nanodevices may guide future intelligent DNA nanorobots to manipulate cascade reactions in biological systems. PMID:25229207
Light-Gated Memristor with Integrated Logic and Memory Functions.
Tan, Hongwei; Liu, Gang; Yang, Huali; Yi, Xiaohui; Pan, Liang; Shang, Jie; Long, Shibing; Liu, Ming; Wu, Yihong; Li, Run-Wei
2017-11-28
Memristive devices are able to store and process information, which offers several key advantages over the transistor-based architectures. However, most of the two-terminal memristive devices have fixed functions once made and cannot be reconfigured for other situations. Here, we propose and demonstrate a memristive device "memlogic" (memory logic) as a nonvolatile switch of logic operations integrated with memory function in a single light-gated memristor. Based on nonvolatile light-modulated memristive switching behavior, a single memlogic cell is able to achieve optical and electrical mixed basic Boolean logic of reconfigurable "AND", "OR", and "NOT" operations. Furthermore, the single memlogic cell is also capable of functioning as an optical adder and digital-to-analog converter. All the memlogic outputs are memristive for in situ data storage due to the nonvolatile resistive switching and persistent photoconductivity effects. Thus, as a memdevice, the memlogic has potential for not only simplifying the programmable logic circuits but also building memristive multifunctional optoelectronics.
The fabrication of a programmable via using phase-change material in CMOS-compatible technology.
Chen, Kuan-Neng; Krusin-Elbaum, Lia
2010-04-02
We demonstrate an energy-efficient programmable via concept using indirectly heated phase-change material. This via structure has maximum phase-change volume to achieve a minimum on resistance for high performance logic applications. Process development and material investigations for this device structure are reported. The device concept is successfully demonstrated in a standard CMOS-compatible technology capable of multiple cycles between on/off states for reconfigurable applications.
NASA Technical Reports Server (NTRS)
Haley, D. C.; Almand, B. J.; Thomas, M. M.; Krauze, L. D.; Gremban, K. D.; Sanborn, J. C.; Kelly, J. H.; Depkovich, T. M.; Wolfe, W. J.; Nguyen, T.
1986-01-01
The purpose of the Robotic Simulation (ROBSIM) program is to provide a broad range of computer capabilities to assist in the design, verification, simulation, and study of robotic systems. ROBSIM is programmed in FORTRAM 77 and implemented on a VAX 11/750 computer using the VMS operating system. The programmer's guide describes the ROBSIM implementation and program logic flow, and the functions and structures of the different subroutines. With the manual and the in-code documentation, an experienced programmer can incorporate additional routines and modify existing ones to add desired capabilities.
Strategic Control Algorithm Development : Volume 4A. Computer Program Report.
DOT National Transportation Integrated Search
1974-08-01
A description of the strategic algorithm evaluation model is presented, both at the user and programmer levels. The model representation of an airport configuration, environmental considerations, the strategic control algorithm logic, and the airplan...
Strategic Control Algorithm Development : Volume 4B. Computer Program Report (Concluded)
DOT National Transportation Integrated Search
1974-08-01
A description of the strategic algorithm evaluation model is presented, both at the user and programmer levels. The model representation of an airport configuration, environmental considerations, the strategic control algorithm logic, and the airplan...
Improving immunization of programmable logic controllers using weighted median filters.
Paredes, José L; Díaz, Dhionel
2005-04-01
This paper addresses the problem of improving immunization of programmable logic controllers (PLC's) to electromagnetic interference with impulsive characteristics. A filtering structure, based on weighted median filters, that does not require additional hardware and can be implemented in legacy PLC's is proposed. The filtering operation is implemented in the binary domain and removes the impulsive noise presented in the discrete input adding thus robustness to PLC's. By modifying the sampling clock structure, two variants of the filter are obtained. Both structures exploit the cyclic nature of the PLC to form an N-sample observation window of the discrete input, hence a status change on it is determined by the filter output taking into account all the N samples avoiding thus that a single impulse affects the PLC functionality. A comparative study, based on a statistical analysis, of the different filters' performances is presented.
Valencia-Palomo, G; Rossiter, J A
2011-01-01
This paper makes two key contributions. First, it tackles the issue of the availability of constrained predictive control for low-level control loops. Hence, it describes how the constrained control algorithm is embedded in an industrial programmable logic controller (PLC) using the IEC 61131-3 programming standard. Second, there is a definition and implementation of a novel auto-tuned predictive controller; the key novelty is that the modelling is based on relatively crude but pragmatic plant information. Laboratory experiment tests were carried out in two bench-scale laboratory systems to prove the effectiveness of the combined algorithm and hardware solution. For completeness, the results are compared with a commercial proportional-integral-derivative (PID) controller (also embedded in the PLC) using the most up to date auto-tuning rules. Copyright © 2010 ISA. Published by Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Yu, Haijun; Li, Guofu; Duo, Liping; Jin, Yuqi; Wang, Jian; Sang, Fengting; Kang, Yuanfu; Li, Liucheng; Wang, Yuanhu; Tang, Shukai; Yu, Hongliang
2015-02-01
A user-friendly data acquisition and control system (DACS) for a pulsed chemical oxygen -iodine laser (PCOIL) has been developed. It is implemented by an industrial control computer,a PLC, and a distributed input/output (I/O) module, as well as the valve and transmitter. The system is capable of handling 200 analogue/digital channels for performing various operations such as on-line acquisition, display, safety measures and control of various valves. These operations are controlled either by control switches configured on a PC while not running or by a pre-determined sequence or timings during the run. The system is capable of real-time acquisition and on-line estimation of important diagnostic parameters for optimization of a PCOIL. The DACS system has been programmed using software programmable logic controller (PLC). Using this DACS, more than 200 runs were given performed successfully.
An acceleration framework for synthetic aperture radar algorithms
NASA Astrophysics Data System (ADS)
Kim, Youngsoo; Gloster, Clay S.; Alexander, Winser E.
2017-04-01
Algorithms for radar signal processing, such as Synthetic Aperture Radar (SAR) are computationally intensive and require considerable execution time on a general purpose processor. Reconfigurable logic can be used to off-load the primary computational kernel onto a custom computing machine in order to reduce execution time by an order of magnitude as compared to kernel execution on a general purpose processor. Specifically, Field Programmable Gate Arrays (FPGAs) can be used to accelerate these kernels using hardware-based custom logic implementations. In this paper, we demonstrate a framework for algorithm acceleration. We used SAR as a case study to illustrate the potential for algorithm acceleration offered by FPGAs. Initially, we profiled the SAR algorithm and implemented a homomorphic filter using a hardware implementation of the natural logarithm. Experimental results show a linear speedup by adding reasonably small processing elements in Field Programmable Gate Array (FPGA) as opposed to using a software implementation running on a typical general purpose processor.
The need for theory evaluation in global citizenship programmes: The case of the GCSA programme.
Goodier, Sarah; Field, Carren; Goodman, Suki
2018-02-01
Many education programmes lack a documented programme theory. This is a problem for programme planners and evaluators as the ability to measure programme success is grounded in the plausibility of the programme's underlying causal logic. Where the programme theory has not been documented, conducting a theory evaluation offers a foundational evaluation step as it gives an indication of whether the theory behind a programme is sound. This paper presents a case of a theory evaluation of a Global Citizenship programme at a top-ranking university in South Africa, subsequently called the GCSA Programme. This evaluation highlights the need for documented programme theory in global citizenship-type programmes for future programme development. An articulated programme theory produced for the GCSA Programme, analysed against the available social science literature, indicated it is comparable to other such programmes in terms of its overarching framework. What the research found is that most other global citizenship programmes do not have an articulated programme theory. These programmes also do not explicitly link their specific activities to their intended outcomes, making demonstrating impact impossible. In conclusion, we argue that taking a theory-based approach can strengthen and enable outcome evaluations in global citizenship programmes. Copyright © 2017. Published by Elsevier Ltd.
Reduction in nevus biopsies in patients monitored by total body photography.
Truong, Amanda; Strazzulla, Lauren; March, Jordon; Boucher, Kenneth M; Nelson, Kelly C; Kim, Caroline C; Grossman, Douglas
2016-07-01
Total body photography (TBP) can facilitate identification of new and changing lesions. By confirming that particular nevi are stable, TBP may reduce nevus biopsies. We sought to determine the number and rate of nevus biopsies before and after TBP, and the factors associated with increased biopsy rate during monitoring by TBP. We reviewed records of all patients in 2 pigmented lesion clinics (PLCs) who received TBP and had 2 or more follow-up visits over a period of 2 years or longer. Before PLCs and TBP, the mean number of nevus biopsies per patient was 5.92 (589 patients) at a mean rate of 1.62 per year (160 patients). After TBP in PLCs, the same patients averaged 1.56 biopsies at a mean rate of 0.34 per year (P < 2 × 10(-16)). The entire cohort (926 patients) averaged similarly low post-TBP biopsy rates of less than 0.2 per year and per visit. Biopsy rates after TBP were positively correlated with decreased age, male gender, and family history of melanoma, but not nevus number. Some information was not available for some patients. Patients at risk for melanoma experienced a 3.8-fold reduction in nevus biopsies after TBP. Younger male patients with family history of melanoma had higher biopsy rates after TBP. Copyright © 2016 American Academy of Dermatology, Inc. Published by Elsevier Inc. All rights reserved.
Anbalagan, M; Yashwanth, R; Jagannadha Rao, A
2004-04-30
Postnatal Leydig cell development in rat involves an initial phase of proliferation of progenitor Leydig cells (PLCs) and subsequent differentiation of these cells into immature Leydig cells (ILCs) and adult Leydig cells (ALCs). With an objective to identify the molecular changes associated with Leydig cell differentiation, the mRNA population in PLCs and ILCs were analyzed by the technique of differential display reverse transcription polymerase chain reaction (DD-RT-PCR). Results revealed differential expression of several transcripts in PLCs and ILCs. Of the several differentially expressed transcripts, the expression of transcripts corresponding to collagen IV alpha6 (Col IV alpha6) and ribosomal protein L 41 (RpL41) decreased during the differentiation of PLC to ILC. Also there was an increase in the expression of transcripts encoding enzymes such as microsomal glutathione-S-transferase (mGST 1) and 7-dehydrocholesterol reductase (7-DHCR) during this process. While Col IV alpha6 and RpL41 are known to be involved in cellular proliferation, mGST 1 and 7-DHCR are essential for normal Leydig cell steroidogenesis. A detailed study on 7-DHCR expression in Leydig cells revealed that this enzyme plays a crucial role in steroidogenesis. Interestingly expression of this enzyme is not under acute regulation by Luteinizing hormone (LH). Copyright 2004 Elsevier Ireland Ltd.
The evolvability of programmable hardware.
Raman, Karthik; Wagner, Andreas
2011-02-06
In biological systems, individual phenotypes are typically adopted by multiple genotypes. Examples include protein structure phenotypes, where each structure can be adopted by a myriad individual amino acid sequence genotypes. These genotypes form vast connected 'neutral networks' in genotype space. The size of such neutral networks endows biological systems not only with robustness to genetic change, but also with the ability to evolve a vast number of novel phenotypes that occur near any one neutral network. Whether technological systems can be designed to have similar properties is poorly understood. Here we ask this question for a class of programmable electronic circuits that compute digital logic functions. The functional flexibility of such circuits is important in many applications, including applications of evolutionary principles to circuit design. The functions they compute are at the heart of all digital computation. We explore a vast space of 10(45) logic circuits ('genotypes') and 10(19) logic functions ('phenotypes'). We demonstrate that circuits that compute the same logic function are connected in large neutral networks that span circuit space. Their robustness or fault-tolerance varies very widely. The vicinity of each neutral network contains circuits with a broad range of novel functions. Two circuits computing different functions can usually be converted into one another via few changes in their architecture. These observations show that properties important for the evolvability of biological systems exist in a commercially important class of electronic circuitry. They also point to generic ways to generate fault-tolerant, adaptable and evolvable electronic circuitry.
The evolvability of programmable hardware
Raman, Karthik; Wagner, Andreas
2011-01-01
In biological systems, individual phenotypes are typically adopted by multiple genotypes. Examples include protein structure phenotypes, where each structure can be adopted by a myriad individual amino acid sequence genotypes. These genotypes form vast connected ‘neutral networks’ in genotype space. The size of such neutral networks endows biological systems not only with robustness to genetic change, but also with the ability to evolve a vast number of novel phenotypes that occur near any one neutral network. Whether technological systems can be designed to have similar properties is poorly understood. Here we ask this question for a class of programmable electronic circuits that compute digital logic functions. The functional flexibility of such circuits is important in many applications, including applications of evolutionary principles to circuit design. The functions they compute are at the heart of all digital computation. We explore a vast space of 1045 logic circuits (‘genotypes’) and 1019 logic functions (‘phenotypes’). We demonstrate that circuits that compute the same logic function are connected in large neutral networks that span circuit space. Their robustness or fault-tolerance varies very widely. The vicinity of each neutral network contains circuits with a broad range of novel functions. Two circuits computing different functions can usually be converted into one another via few changes in their architecture. These observations show that properties important for the evolvability of biological systems exist in a commercially important class of electronic circuitry. They also point to generic ways to generate fault-tolerant, adaptable and evolvable electronic circuitry. PMID:20534598
NASA Astrophysics Data System (ADS)
Liu, Tianqi; Yang, Zhenlei; Guo, Jinlong; Du, Guanghua; Tong, Teng; Wang, Xiaohui; Su, Hong; Liu, Wenjing; Liu, Jiande; Wang, Bin; Ye, Bing; Liu, Jie
2017-08-01
The heavy-ion imaging of single event upset (SEU) in a flash-based field programmable gate array (FPGA) device was carried out for the first time at Heavy Ion Research Facility in Lanzhou (HIRFL). The three shift register chains with separated input and output configurations in device under test (DUT) were used to identify the corresponding logical area rapidly once an upset occurred. The logic units in DUT were partly configured in order to distinguish the registers in SEU images. Based on the above settings, the partial architecture of shift register chains in DUT was imaged by employing the microbeam of 86Kr ion with energy of 25 MeV/u in air. The results showed that the physical distribution of registers in DUT had a high consistency with its logical arrangement by comparing SEU image with logic configuration in scanned area.
Single board system for fuzzy inference
NASA Technical Reports Server (NTRS)
Symon, James R.; Watanabe, Hiroyuki
1991-01-01
The very large scale integration (VLSI) implementation of a fuzzy logic inference mechanism allows the use of rule-based control and decision making in demanding real-time applications. Researchers designed a full custom VLSI inference engine. The chip was fabricated using CMOS technology. The chip consists of 688,000 transistors of which 476,000 are used for RAM memory. The fuzzy logic inference engine board system incorporates the custom designed integrated circuit into a standard VMEbus environment. The Fuzzy Logic system uses Transistor-Transistor Logic (TTL) parts to provide the interface between the Fuzzy chip and a standard, double height VMEbus backplane, allowing the chip to perform application process control through the VMEbus host. High level C language functions hide details of the hardware system interface from the applications level programmer. The first version of the board was installed on a robot at Oak Ridge National Laboratory in January of 1990.
78 FR 13747 - Safety Advisory 2013-01; Passing Stop Signals Protecting Movable Bridges
Federal Register 2010, 2011, 2012, 2013, 2014
2013-02-28
... 82 freight cars, including 51 hazardous materials tank cars, derailed seven cars while crossing a... bridge to close using the key pad on the locomotive radio. Through the use of a programmable logic...
The Integration of DCS I/O to an Existing PLC
NASA Technical Reports Server (NTRS)
Sadhukhan, Debashis; Mihevic, John
2013-01-01
At the NASA Glenn Research Center (GRC), Existing Programmable Logic Controller (PLC) I/O was replaced with Distributed Control System (DCS) I/O, while keeping the existing PLC sequence Logic. The reason for integration of the PLC logic and DCS I/O, along with the evaluation of the resulting system is the subject of this paper. The pros and cons of the old system and new upgrade are described, including operator workstation screen update times. Detail of the physical layout and the communication between the PLC, the DCS I/O and the operator workstations are illustrated. The complex characteristics of a central process control system and the plan to remove the PLC processors in future upgrades is also discussed.
Programming Cell Adhesion for On-Chip Sequential Boolean Logic Functions.
Qu, Xiangmeng; Wang, Shaopeng; Ge, Zhilei; Wang, Jianbang; Yao, Guangbao; Li, Jiang; Zuo, Xiaolei; Shi, Jiye; Song, Shiping; Wang, Lihua; Li, Li; Pei, Hao; Fan, Chunhai
2017-08-02
Programmable remodelling of cell surfaces enables high-precision regulation of cell behavior. In this work, we developed in vitro constructed DNA-based chemical reaction networks (CRNs) to program on-chip cell adhesion. We found that the RGD-functionalized DNA CRNs are entirely noninvasive when interfaced with the fluidic mosaic membrane of living cells. DNA toehold with different lengths could tunably alter the release kinetics of cells, which shows rapid release in minutes with the use of a 6-base toehold. We further demonstrated the realization of Boolean logic functions by using DNA strand displacement reactions, which include multi-input and sequential cell logic gates (AND, OR, XOR, and AND-OR). This study provides a highly generic tool for self-organization of biological systems.
Excitonic AND Logic Gates on DNA Brick Nanobreadboards.
Cannon, Brittany L; Kellis, Donald L; Davis, Paul H; Lee, Jeunghoon; Kuang, Wan; Hughes, William L; Graugnard, Elton; Yurke, Bernard; Knowlton, William B
2015-03-18
A promising application of DNA self-assembly is the fabrication of chromophore-based excitonic devices. DNA brick assembly is a compelling method for creating programmable nanobreadboards on which chromophores may be rapidly and easily repositioned to prototype new excitonic devices, optimize device operation, and induce reversible switching. Using DNA nanobreadboards, we have demonstrated each of these functions through the construction and operation of two different excitonic AND logic gates. The modularity and high chromophore density achievable via this brick-based approach provide a viable path toward developing information processing and storage systems.
Excitonic AND Logic Gates on DNA Brick Nanobreadboards
2015-01-01
A promising application of DNA self-assembly is the fabrication of chromophore-based excitonic devices. DNA brick assembly is a compelling method for creating programmable nanobreadboards on which chromophores may be rapidly and easily repositioned to prototype new excitonic devices, optimize device operation, and induce reversible switching. Using DNA nanobreadboards, we have demonstrated each of these functions through the construction and operation of two different excitonic AND logic gates. The modularity and high chromophore density achievable via this brick-based approach provide a viable path toward developing information processing and storage systems. PMID:25839049
Instantaneous relationship between solar inertial and local vertical local horizontal attitudes
NASA Technical Reports Server (NTRS)
Vickery, S. A.
1977-01-01
The instantaneous relationship between the Solar Inertial (SI) and Local Vertical Local Horizontal (LVLH) coordinate systems is derived. A method is presented for computation of the LVLH to SI rotational transformation matrix as a function of an input LVLH attitude and the corresponding look angles to the sun. Logic is provided for conversion between LVLH and SI attitudes expressed in terms of a pitch, yaw, roll Euler sequence. Documentation is included for a program which implements the logic on the Hewlett-Packard 97 programmable calculator.
Devaraju, Naga Sai Gopi K; Unger, Marc A
2012-11-21
Advances in microfluidics now allow an unprecedented level of parallelization and integration of biochemical reactions. However, one challenge still faced by the field has been the complexity and cost of the control hardware: one external pressure signal has been required for each independently actuated set of valves on chip. Using a simple post-modification to the multilayer soft lithography fabrication process, we present a new implementation of digital fluidic logic fully analogous to electronic logic with significant performance advances over the previous implementations. We demonstrate a novel normally closed static gain valve capable of modulating pressure signals in a fashion analogous to an electronic transistor. We utilize these valves to build complex fluidic logic circuits capable of arbitrary control of flows by processing binary input signals (pressure (1) and atmosphere (0)). We demonstrate logic gates and devices including NOT, NAND and NOR gates, bi-stable flip-flops, gated flip-flops (latches), oscillators, self-driven peristaltic pumps, delay flip-flops, and a 12-bit shift register built using static gain valves. This fluidic logic shows cascade-ability, feedback, programmability, bi-stability, and autonomous control capability. This implementation of fluidic logic yields significantly smaller devices, higher clock rates, simple designs, easy fabrication, and integration into MSL microfluidics.
Information Retrieval Research and ESPRIT.
ERIC Educational Resources Information Center
Smeaton, Alan F.
1987-01-01
Describes the European Strategic Programme of Research and Development in Information Technology (ESPRIT), and its five programs: advanced microelectronics, software technology, advanced information processing, office systems, and computer integrated manufacturing. The emphasis on logic programming and ESPRIT as the European response to the…
Leerlooijer, Joanne N; Ruiter, Robert A C; Reinders, Jo; Darwisyah, Wati; Kok, Gerjo; Bartholomew, L Kay
2011-06-01
Evidence-based health promotion programmes, including HIV/AIDS prevention and sexuality education programmes, are often transferred to other cultures, priority groups and implementation settings. Challenges in this process include the identification of retaining core elements that relate to the programme's effectiveness while making changes that enhances acceptance in the new context and for the new priority group. This paper describes the use of a systematic approach to programme adaptation using a case study as an example. Intervention Mapping, a protocol for the development of evidence-based behaviour change interventions, was used to adapt the comprehensive school-based sexuality education programme 'The World Starts With Me'. The programme was developed for a priority population in Uganda and adapted to a programme for Indonesian secondary school students. The approach helped to systematically address the complexity and challenges of programme adaptation and to find a balance between preservation of essential programme elements (i.e. logic models) that may be crucial to the programme's effectiveness, including key objectives and theoretical behaviour change methods, and the adaptation of the programme to be acceptable to the new priority group and the programme implementers.
Magnetic-field-controlled reconfigurable semiconductor logic.
Joo, Sungjung; Kim, Taeyueb; Shin, Sang Hoon; Lim, Ju Young; Hong, Jinki; Song, Jin Dong; Chang, Joonyeon; Lee, Hyun-Woo; Rhie, Kungwon; Han, Suk Hee; Shin, Kyung-Ho; Johnson, Mark
2013-02-07
Logic devices based on magnetism show promise for increasing computational efficiency while decreasing consumed power. They offer zero quiescent power and yet combine novel functions such as programmable logic operation and non-volatile built-in memory. However, practical efforts to adapt a magnetic device to logic suffer from a low signal-to-noise ratio and other performance attributes that are not adequate for logic gates. Rather than exploiting magnetoresistive effects that result from spin-dependent transport of carriers, we have approached the development of a magnetic logic device in a different way: we use the phenomenon of large magnetoresistance found in non-magnetic semiconductors in high electric fields. Here we report a device showing a strong diode characteristic that is highly sensitive to both the sign and the magnitude of an external magnetic field, offering a reversible change between two different characteristic states by the application of a magnetic field. This feature results from magnetic control of carrier generation and recombination in an InSb p-n bilayer channel. Simple circuits combining such elementary devices are fabricated and tested, and Boolean logic functions including AND, OR, NAND and NOR are performed. They are programmed dynamically by external electric or magnetic signals, demonstrating magnetic-field-controlled semiconductor reconfigurable logic at room temperature. This magnetic technology permits a new kind of spintronic device, characterized as a current switch rather than a voltage switch, and provides a simple and compact platform for non-volatile reconfigurable logic devices.
An autonomous molecular computer for logical control of gene expression.
Benenson, Yaakov; Gil, Binyamin; Ben-Dor, Uri; Adar, Rivka; Shapiro, Ehud
2004-05-27
Early biomolecular computer research focused on laboratory-scale, human-operated computers for complex computational problems. Recently, simple molecular-scale autonomous programmable computers were demonstrated allowing both input and output information to be in molecular form. Such computers, using biological molecules as input data and biologically active molecules as outputs, could produce a system for 'logical' control of biological processes. Here we describe an autonomous biomolecular computer that, at least in vitro, logically analyses the levels of messenger RNA species, and in response produces a molecule capable of affecting levels of gene expression. The computer operates at a concentration of close to a trillion computers per microlitre and consists of three programmable modules: a computation module, that is, a stochastic molecular automaton; an input module, by which specific mRNA levels or point mutations regulate software molecule concentrations, and hence automaton transition probabilities; and an output module, capable of controlled release of a short single-stranded DNA molecule. This approach might be applied in vivo to biochemical sensing, genetic engineering and even medical diagnosis and treatment. As a proof of principle we programmed the computer to identify and analyse mRNA of disease-related genes associated with models of small-cell lung cancer and prostate cancer, and to produce a single-stranded DNA molecule modelled after an anticancer drug.
Optically Programmable Field Programmable Gate Arrays (FPGA) Systems
2004-01-01
VCSEL requires placing the array far enough as to overlap the entire footprint of the signal beam in order to record the hologram. Therefore, these...hologram that self-focuses, due to phase -conjugation, on the array of detectors in the chip. VC A 10 m m 10 mm 18mm 16mm SEL RRAY OPTICAL MEMORY LOGIC...the VCSEL array , the chip and the optical material, and the requirements they have to meet for their use in the OPGA system. Section
Lifelines for High School Climate Change Education
NASA Astrophysics Data System (ADS)
Gould, A. D.
2012-12-01
The Lifelines project aims to establish a network of practicing high school teachers actively using climate change curricula by creating professional learning communities (PLCs) of teachers who, through remote meetings and workshops, maintain ongoing communication and sharing of best practices among colleagues to strengthen knowledge and promote effective teaching strategies. The project explores techniques to achieve the most effective teleconferencing meetings and workshops. This promotes not only teaching about minimizing environmental impacts of human activity, but minimizes environmental impacts of professional development — practicing what we preach. To date, Lifelines PLCs have set up websites and e-mail lists for sharing information. Teleconferences and webinars have been held using services such as Skype, ReadyTalk, and Wiggio. Many of the meetings have been recorded and archived for the benefit of members who could not attend in real-time.
Change Management in Dental Education: A Professional Learning Community.
Palatta, Anthony M
2018-06-01
Professional learning communities (PLCs) are defined as "a group of people sharing and critically interrogating their practice in an ongoing, reflective, collaborative, inclusive, learning-oriented, growth-promoting way." PLCs have been found to be an effective change management strategy in business and education when confronted by rapid change. The American Dental Education Association's Commission on Change and Innovation in Dental Education new national program-ADEA CCI 2.0-includes the development of a PLC. By employing an "engage and learn" model PLC centered on continuous quality improvement and systems thinking, dental faculty can identify internal and external barriers to change that could lead to innovative solutions to complex issues. This article argues that a PLC is a viable change management strategy to counteract the effect of multiple external forces impacting dental education and thus to develop future-ready faculty.
Electromechanical Componentry. High-Technology Training Module.
ERIC Educational Resources Information Center
Lindemann, Don
This training module on electromechanical components contains 10 units for a two-year vocational program packaging system equipment control course at Wisconsin Indianhead Technical College. This module describes the functions of electromechanical devices essential for understanding input/output devices for Programmable Logic Control (PLC)…
A three-sided rearrangeable switching network for a binary fat tree
NASA Astrophysics Data System (ADS)
Yen, Mao-Hsu; Yu, Chu; Shin, Haw-Yun; Chen, Sao-Jie
2011-06-01
A binary fat tree needs an internal node to interconnect the left-children, right-children and parent terminals to each other. In this article, we first propose a three-stage, 3-sided rearrangeable switching network for the implementation of a binary fat tree. The main component of this 3-sided switching network (3SSN) consists of a polygonal switch block (PSB) interconnected by crossbars. With the same size and the same number of switches as our 3SSN, a three-stage, 3-sided clique-based switching network is shown to be not rearrangeable. Also, the effects of the rearrangeable structure and the number of terminals on the network switch-efficiency are explored and a proper set of parameters has been determined to minimise the number of switches. We derive that a rearrangeable 3-sided switching network with switches proportional to N 3/2 is most suitable to interconnect N terminals. Moreover, we propose a new Polygonal Field Programmable Gate Array (PFPGA) that consists of logic blocks interconnected by our 3SSN, such that the logic blocks in this PFPGA can be grouped into clusters to implement different logic functions. Since the programmable switches usually have high resistance and capacitance and occupy a large area, we have to consider the effect of the 3SSN structure and the granularity of its cluster logic blocks on the switch efficiency of PFPGA. Experiments on benchmark circuits show that the switch and speed performances are significantly improved. Based on the experimental results, we can determine the parameters of PFPGA for the VLSI implementation.
Logical enzyme triggered (LET) layer-by-layer nanocapsules for drug delivery system
NASA Astrophysics Data System (ADS)
Kelley, Marie-Michelle
Breast cancer is the second leading cause of morbidity and mortality among women in the United States. Early detection and treatment methods have resulted in 100% 5-year survival rates for stage 0-I breast cancer. Unfortunately, the 5-year survival rate of metastatic breast cancer (stage IV) is reduced fivefold. The most challenging issues of metastatic breast cancer treatment are the ability to selectively target the adenoma and adenocarcinoma cells both in their location of origin and as they metastasize following initial treatment. Multilayer/Layer-by-Layer (LbL) nanocapsules have garnered vast interest as anticancer drug delivery systems due to their ability to be easily modified, their capacity to encapsulate a wide range of chemicals and proteins, and their improved pharmacokinetics. Multilayer nanocapsule formation requires the layering of opposing charged polyelectrolytic polymers over a removable core nanoparticle. Our goal is to have a programmable nanocapsules degrade only after receiving and validating specific breast cancer biomarkers. The overall objective is to fabricate a novel programmable LbL nanocapsule with a specific logical system that will enhance functions pertinent to drug delivery systems. Our central hypothesis is that LbL technology coupled with extracellular matrix (ECM) protein substrates will result in a logical enzyme triggered LbL nanocapsule drug delivery system. This platform represents a novel approach toward a logically regulated nano-encapsulated cancer therapy that can selectively follow and deliver chemotherapeutics to cancer cells. The rationale for this project is to overcome a crucial limitation of existing drug delivery systems where chemotherapeutic can be erroneously delivered to non-carcinogenic cells.
An IO block array in a radiation-hardened SOI SRAM-based FPGA
NASA Astrophysics Data System (ADS)
Yan, Zhao; Lihua, Wu; Xiaowei, Han; Yan, Li; Qianli, Zhang; Liang, Chen; Guoquan, Zhang; Jianzhong, Li; Bo, Yang; Jiantou, Gao; Jian, Wang; Ming, Li; Guizhai, Liu; Feng, Zhang; Xufeng, Guo; Kai, Zhao; Chen, Stanley L.; Fang, Yu; Zhongli, Liu
2012-01-01
We present an input/output block (IOB) array used in the radiation-hardened SRAM-based field-programmable gate array (FPGA) VS1000, which is designed and fabricated with a 0.5 μm partially depleted silicon-on-insulator (SOI) logic process at the CETC 58th Institute. Corresponding with the characteristics of the FPGA, each IOB includes a local routing pool and two IO cells composed of a signal path circuit, configurable input/output buffers and an ESD protection network. A boundary-scan path circuit can be used between the programmable buffers and the input/output circuit or as a transparent circuit when the IOB is applied in different modes. Programmable IO buffers can be used at TTL/CMOS standard levels. The local routing pool enhances the flexibility and routability of the connection between the IOB array and the core logic. Radiation-hardened designs, including A-type and H-type body-tied transistors and special D-type registers, improve the anti-radiation performance. The ESD protection network, which provides a high-impulse discharge path on a pad, prevents the breakdown of the core logic caused by the immense current. These design strategies facilitate the design of FPGAs with different capacities or architectures to form a series of FPGAs. The functionality and performance of the IOB array is proved after a functional test. The radiation test indicates that the proposed VS1000 chip with an IOB array has a total dose tolerance of 100 krad(Si), a dose survivability rate of 1.5 × 1011 rad(Si)/s, and a neutron fluence immunity of 1 × 1014 n/cm2.
Summary of Proton Test on the Quick Logic QL3025 at Indiana University
NASA Technical Reports Server (NTRS)
Katz, Richard
1998-01-01
This issue of the Programmable Logic Application Notes is a compilation of topics: (1) Proton irradiation tests were performed on the Quick Logic QL3025 at the Indian University Cyclotron facility. The devices, tests, and results are discussed; (2) The functional failure of EEPROM's in heavy ion environment is presented; (3) the Act 1 architecture is summarized; (4) Antifuse hardness and hardness testing is updated; the single even upset (SEU) response of hardwired flip-flops is also presented; (4) Total dose results of the ACT 2 and ACT 3 circuits is presented in a chart; (5) Recent sub-micron devices testing of total dose is presented in a chart along with brief discussion; and (6) a reference to the WWW site for more articles of interest.
A programmable CCD driver circuit for multiphase CCD operation
NASA Technical Reports Server (NTRS)
Ewin, Audrey J.; Reed, Kenneth V.
1989-01-01
A programmable CCD (charge-coupled device) driver circuit was designed to drive CCDs in multiphased modes. The purpose of the drive electronics is to operate developmental CCD imaging arrays for NASA's tiltable moderate resolution imaging spectrometer (MODIS-T). Five objectives for the driver were considered during its design: (1) the circuit drives CCD electrode voltages between 0 V and +30 V to produce reasonable potential wells, (2) the driving sequence is started with one input signal, (3) the driving sequence is started with one input signal, (4) the circuit allows programming of frame sequences required by arrays of any size, (5) it produces interfacing signals for the CCD and the DTF (detector test facility). Simulation of the driver verified its function with the master clock running up to 10 MHz. This suggests a maximum rate of 400,000 pixels/s. Timing and packaging parameters were verified. The design uses 54 TTL (transistor-transistor logic) chips. Two versions of hardware were fabricated: wirewrap and printed circuit board. Both were verified functionally with a logic analyzer.
NASA Astrophysics Data System (ADS)
Wang, Tai-Min; Chien, Wei-Yu; Hsu, Chia-Ling; Lin, Chrong Jung; King, Ya-Chin
2018-04-01
In this paper, we present a new differential p-channel multiple-time programmable (MTP) memory cell that is fully compatible with advanced 16 nm CMOS fin field-effect transistors (FinFET) logic processes. This differential MTP cell stores complementary data in floating gates coupled by a slot contact structure, which make different read currents possible on a single cell. In nanoscale CMOS FinFET logic processes, the gate dielectric layer becomes too thin to retain charges inside floating gates for nonvolatile data storage. By using a differential architecture, the sensing window of the cell can be extended and maintained by an advanced blanket boost scheme. The charge retention problem in floating gate cells can be improved by periodic restoring lost charges when significant read window narrowing occurs. In addition to high programming efficiency, this p-channel MTP cells also exhibit good cycling endurance as well as disturbance immunity. The blanket boost scheme can remedy the charge loss problem under thin gate dielectrics.
Détermination assistée par ordinateur de la structure des molécules organiques
NASA Astrophysics Data System (ADS)
Nuzillard, J.-M.
1998-02-01
Nuclear Magnetic Resonance spectroscopy offers the unique possibility of accessing proximity relationships between atoms by means of chemical shift correlation experiments. Structure determination of small molecules has become thus much simpler. Computer programs can use directly correlation information for structure analysis. The use and operation mechanism of such a program, LSD (Logic for Structure Determination) are presented. The example compound is gibberellic acid, a natural product. La spectroscopie de Résonance Magnétique Nucléaire offre un moyen unique de déterminer des relations de proximité entre atomes par le biais des expériences de corrélation. L'analyse structurale de petites molécules organiques s'en trouve extrêmement facilitée. Des programmes informatiques peuvent utiliser directement les informations de corrélation pour déduire des structures. Le fonctionnement et l'usage d'un tel programme, LSD (Logic for Structure Determination), sont détaillés sur un exemple, l'acide gibberellique.
Graphene-ferroelectric metadevices for nonvolatile memory and reconfigurable logic-gate operations.
Kim, Woo Young; Kim, Hyeon-Don; Kim, Teun-Teun; Park, Hyun-Sung; Lee, Kanghee; Choi, Hyun Joo; Lee, Seung Hoon; Son, Jaehyeon; Park, Namkyoo; Min, Bumki
2016-01-27
Memory metamaterials are artificial media that sustain transformed electromagnetic properties without persistent external stimuli. Previous memory metamaterials were realized with phase-change materials, such as vanadium dioxide or chalcogenide glasses, which exhibit memory behaviour with respect to electrically/optically induced thermal stimuli. However, they require a thermally isolated environment for longer retention or strong optical pump for phase-change. Here we demonstrate electrically programmable nonvolatile memory metadevices realised by the hybridization of graphene, a ferroelectric and meta-atoms/meta-molecules, and extend the concept further to establish reconfigurable logic-gate metadevices. For a memory metadevice having a single electrical input, amplitude, phase and even the polarization multi-states were clearly distinguishable with a retention time of over 10 years at room temperature. Furthermore, logic-gate functionalities were demonstrated with reconfigurable logic-gate metadevices having two electrical inputs, with each connected to separate ferroelectric layers that act as the multi-level controller for the doping level of the sandwiched graphene layer.
Majority logic gate for 3D magnetic computing.
Eichwald, Irina; Breitkreutz, Stephan; Ziemys, Grazvydas; Csaba, György; Porod, Wolfgang; Becherer, Markus
2014-08-22
For decades now, microelectronic circuits have been exclusively built from transistors. An alternative way is to use nano-scaled magnets for the realization of digital circuits. This technology, known as nanomagnetic logic (NML), may offer significant improvements in terms of power consumption and integration densities. Further advantages of NML are: non-volatility, radiation hardness, and operation at room temperature. Recent research focuses on the three-dimensional (3D) integration of nanomagnets. Here we show, for the first time, a 3D programmable magnetic logic gate. Its computing operation is based on physically field-interacting nanometer-scaled magnets arranged in a 3D manner. The magnets possess a bistable magnetization state representing the Boolean logic states '0' and '1.' Magneto-optical and magnetic force microscopy measurements prove the correct operation of the gate over many computing cycles. Furthermore, micromagnetic simulations confirm the correct functionality of the gate even for a size in the nanometer-domain. The presented device demonstrates the potential of NML for three-dimensional digital computing, enabling the highest integration densities.
Graphene-ferroelectric metadevices for nonvolatile memory and reconfigurable logic-gate operations
NASA Astrophysics Data System (ADS)
Kim, Woo Young; Kim, Hyeon-Don; Kim, Teun-Teun; Park, Hyun-Sung; Lee, Kanghee; Choi, Hyun Joo; Lee, Seung Hoon; Son, Jaehyeon; Park, Namkyoo; Min, Bumki
2016-01-01
Memory metamaterials are artificial media that sustain transformed electromagnetic properties without persistent external stimuli. Previous memory metamaterials were realized with phase-change materials, such as vanadium dioxide or chalcogenide glasses, which exhibit memory behaviour with respect to electrically/optically induced thermal stimuli. However, they require a thermally isolated environment for longer retention or strong optical pump for phase-change. Here we demonstrate electrically programmable nonvolatile memory metadevices realised by the hybridization of graphene, a ferroelectric and meta-atoms/meta-molecules, and extend the concept further to establish reconfigurable logic-gate metadevices. For a memory metadevice having a single electrical input, amplitude, phase and even the polarization multi-states were clearly distinguishable with a retention time of over 10 years at room temperature. Furthermore, logic-gate functionalities were demonstrated with reconfigurable logic-gate metadevices having two electrical inputs, with each connected to separate ferroelectric layers that act as the multi-level controller for the doping level of the sandwiched graphene layer.
Mertaniemi, Henrikki; Forchheimer, Robert; Ikkala, Olli; Ras, Robin H A
2012-11-08
When water droplets impact each other while traveling on a superhydrophobic surface, we demonstrate that they are able to rebound like billiard balls. We present elementary Boolean logic operations and a flip-flop memory based on these rebounding water droplet collisions. Furthermore, bouncing or coalescence can be easily controlled by process parameters. Thus by the controlled coalescence of reactive droplets, here using the quenching of fluorescent metal nanoclusters as a model reaction, we also demonstrate an elementary operation for programmable chemistry. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Light-driven OR and XOR programmable chemical logic gates.
Szaciłowski, Konrad; Macyk, Wojciech; Stochel, Grazyna
2006-04-12
Photoelectrodes made of nanocrystalline titanium dioxide modified with various pentacyanoferrates exhibit unique photoelectrochemical properties; photocurrent direction can be switched from anodic to cathodic and vice versa upon changes in photoelectrode potential and incident light wavelength (PhotoElectrochemical Photocurrent Switching, PEPS effect). At certain potentials, anodic photocurrent generated upon UV irradiation has the same intensity as the cathodic photocurrent generated upon visible irradiation. Under these conditions, simultaneous irradiation with UV and visible light results in compensation of anodic and cathodic photocurrents, and zero net photocurrent is observed. This process can be used for construction of unique light-driven chemical logic gates.
NASA Astrophysics Data System (ADS)
Popa, L.; Popa, V.
2017-08-01
The article is focused on modeling an automated industrial robotic arm operated electro-pneumatically and to simulate the robotic arm operation. It is used the graphic language FBD (Function Block Diagram) to program the robotic arm on Zelio Logic automation. The innovative modeling and simulation procedures are considered specific problems regarding the development of a new type of technical products in the field of robotics. Thus, were identified new applications of a Programmable Logic Controller (PLC) as a specialized computer performing control functions with a variety of high levels of complexit.
Radio Frequency Based Programmable Logic Controller Anomaly Detection
2013-09-01
include wireless radios, IEEE 802.15 Blue- tooth devices, cellular phones, and IEEE 802.11 WiFi networking devices. While wireless communication...MacKenzie, H. Shamoon Malware and SCADA Security What are the Im- pacts? . Technical Report, Tofino Security, Sep 2012. 61. Mateti,P. Hacking Techniques
Programmable DNA switches and their applications.
Harroun, Scott G; Prévost-Tremblay, Carl; Lauzon, Dominic; Desrosiers, Arnaud; Wang, Xiaomeng; Pedro, Liliana; Vallée-Bélisle, Alexis
2018-03-08
DNA switches are ideally suited for numerous nanotechnological applications, and increasing efforts are being directed toward their engineering. In this review, we discuss how to engineer these switches starting from the selection of a specific DNA-based recognition element, to its adaptation and optimisation into a switch, with applications ranging from sensing to drug delivery, smart materials, molecular transporters, logic gates and others. We provide many examples showcasing their high programmability and recent advances towards their real life applications. We conclude with a short perspective on this exciting emerging field.
ANOPP programmer's reference manual for the executive System. [aircraft noise prediction program
NASA Technical Reports Server (NTRS)
Gillian, R. E.; Brown, C. G.; Bartlett, R. W.; Baucom, P. H.
1977-01-01
Documentation for the Aircraft Noise Prediction Program as of release level 01/00/00 is presented in a manual designed for programmers having a need for understanding the internal design and logical concepts of the executive system software. Emphasis is placed on providing sufficient information to modify the system for enhancements or error correction. The ANOPP executive system includes software related to operating system interface, executive control, and data base management for the Aircraft Noise Prediction Program. It is written in Fortran IV for use on CDC Cyber series of computers.
Recognizing and engineering digital-like logic gates and switches in gene regulatory networks.
Bradley, Robert W; Buck, Martin; Wang, Baojun
2016-10-01
A central aim of synthetic biology is to build organisms that can perform useful activities in response to specified conditions. The digital computing paradigm which has proved so successful in electrical engineering is being mapped to synthetic biological systems to allow them to make such decisions. However, stochastic molecular processes have graded input-output functions, thus, bioengineers must select those with desirable characteristics and refine their transfer functions to build logic gates with digital-like switching behaviour. Recent efforts in genome mining and the development of programmable RNA-based switches, especially CRISPRi, have greatly increased the number of parts available to synthetic biologists. Improvements to the digital characteristics of these parts are required to enable robust predictable design of deeply layered logic circuits. Copyright © 2016 The Author(s). Published by Elsevier Ltd.. All rights reserved.
Nanoeletromechanical switch and logic circuits formed therefrom
Nordquist, Christopher D [Albuquerque, NM; Czaplewski, David A [Albuquerque, NM
2010-05-18
A nanoelectromechanical (NEM) switch is formed on a substrate with a source electrode containing a suspended electrically-conductive beam which is anchored to the substrate at each end. This beam, which can be formed of ruthenium, bows laterally in response to a voltage applied between a pair of gate electrodes and the source electrode to form an electrical connection between the source electrode and a drain electrode located near a midpoint of the beam. Another pair of gate electrodes and another drain electrode can be located on an opposite side of the beam to allow for switching in an opposite direction. The NEM switch can be used to form digital logic circuits including NAND gates, NOR gates, programmable logic gates, and SRAM and DRAM memory cells which can be used in place of conventional CMOS circuits, or in combination therewith.
Transformations of software design and code may lead to reduced errors
NASA Technical Reports Server (NTRS)
Connelly, E. M.
1983-01-01
The capability of programmers and non-programmers to specify problem solutions by developing example-solutions and also for the programmers by writing computer programs was investigated; each method of specification was accomplished at various levels of problem complexity. The level of difficulty of each problem was reflected by the number of steps needed by the user to develop a solution. Machine processing of the user inputs permitted inferences to be developed about the algorithms required to solve a particular problem. The interactive feedback of processing results led users to a more precise definition of the desired solution. Two participant groups (programmers and bookkeepers/accountants) working with three levels of problem complexity and three levels of processor complexity were used. The experimental task employed required specification of a logic for solution of a Navy task force problem.
NASA Astrophysics Data System (ADS)
Yang, Bin; Zhang, Xiao-Bing; Kang, Li-Ping; Huang, Zhi-Mei; Shen, Guo-Li; Yu, Ru-Qin; Tan, Weihong
2014-07-01
DNA strand displacement cascades have been engineered to construct various fascinating DNA circuits. However, biological applications are limited by the insufficient cellular internalization of naked DNA structures, as well as the separated multicomponent feature. In this work, these problems are addressed by the development of a novel DNA nanodevice, termed intelligent layered nanoflare, which integrates DNA computing at the nanoscale, via the self-assembly of DNA flares on a single gold nanoparticle. As a ``lab-on-a-nanoparticle'', the intelligent layered nanoflare could be engineered to perform a variety of Boolean logic gate operations, including three basic logic gates, one three-input AND gate, and two complex logic operations, in a digital non-leaky way. In addition, the layered nanoflare can serve as a programmable strategy to sequentially tune the size of nanoparticles, as well as a new fingerprint spectrum technique for intelligent multiplex biosensing. More importantly, the nanoflare developed here can also act as a single entity for intracellular DNA logic gate delivery, without the need of commercial transfection agents or other auxiliary carriers. By incorporating DNA circuits on nanoparticles, the presented layered nanoflare will broaden the applications of DNA circuits in biological systems, and facilitate the development of DNA nanotechnology.DNA strand displacement cascades have been engineered to construct various fascinating DNA circuits. However, biological applications are limited by the insufficient cellular internalization of naked DNA structures, as well as the separated multicomponent feature. In this work, these problems are addressed by the development of a novel DNA nanodevice, termed intelligent layered nanoflare, which integrates DNA computing at the nanoscale, via the self-assembly of DNA flares on a single gold nanoparticle. As a ``lab-on-a-nanoparticle'', the intelligent layered nanoflare could be engineered to perform a variety of Boolean logic gate operations, including three basic logic gates, one three-input AND gate, and two complex logic operations, in a digital non-leaky way. In addition, the layered nanoflare can serve as a programmable strategy to sequentially tune the size of nanoparticles, as well as a new fingerprint spectrum technique for intelligent multiplex biosensing. More importantly, the nanoflare developed here can also act as a single entity for intracellular DNA logic gate delivery, without the need of commercial transfection agents or other auxiliary carriers. By incorporating DNA circuits on nanoparticles, the presented layered nanoflare will broaden the applications of DNA circuits in biological systems, and facilitate the development of DNA nanotechnology. Electronic supplementary information (ESI) available: Additional figures (Table S1, Fig. S1-S5). See DOI: 10.1039/c4nr01676a
NASA Astrophysics Data System (ADS)
Okamoto, Satoru; Sato, Takehiro; Yamanaka, Naoaki
2017-01-01
In this paper, flexible and highly reliable metro and access integrated networks with network virtualization and software defined networking technologies will be presented. Logical optical line terminal (L-OLT) technologies and active optical distribution networks (ODNs) are the key to introduce flexibility and high reliability into the metro and access integrated networks. In the Elastic Lambda Aggregation Network (EλAN) project which was started in 2012, a concept of the programmable optical line terminal (P-OLT) has been proposed. A role of the P-OLT is providing multiple network services that have different protocols and quality of service requirements by single OLT box. Accommodated services will be Internet access, mobile front-haul/back-haul, data-center access, and leased line. L-OLTs are configured within the P-OLT box to support the functions required for each network service. Multiple P-OLTs and programmable optical network units (P-ONUs) are connected by the active ODN. Optical access paths which have flexible capacity are set on the ODN to provide network services from L-OLT to logical ONUs (L-ONUs). The L-OLT to L-ONU path on the active ODN provides a logical connection. Therefore, introducing virtualization technologies becomes possible. One example is moving an L-OLT from one P-OLT to another P-OLT like a virtual machine. This movement is called L-OLT migration. The L-OLT migration provides flexible and reliable network functions such as energy saving by aggregating L-OLTs to a limited number of P-OLTs, and network wide optical access path restoration. Other L-OLT virtualization technologies and experimental results will be also discussed in the paper.
Research on NC motion controller based on SOPC technology
NASA Astrophysics Data System (ADS)
Jiang, Tingbiao; Meng, Biao
2006-11-01
With the rapid development of the digitization and informationization, the application of numerical control technology in the manufacturing industry becomes more and more important. However, the conventional numerical control system usually has some shortcomings such as the poor in system openness, character of real-time, cutability and reconfiguration. In order to solve these problems, this paper investigates the development prospect and advantage of the application in numerical control area with system-on-a-Programmable-Chip (SOPC) technology, and puts forward to a research program approach to the NC controller based on SOPC technology. Utilizing the characteristic of SOPC technology, we integrate high density logic device FPGA, memory SRAM, and embedded processor ARM into a single programmable logic device. We also combine the 32-bit RISC processor with high computing capability of the complicated algorithm with the FPGA device with strong motivable reconfiguration logic control ability. With these steps, we can greatly resolve the defect described in above existing numerical control systems. For the concrete implementation method, we use FPGA chip embedded with ARM hard nuclear processor to construct the control core of the motion controller. We also design the peripheral circuit of the controller according to the requirements of actual control functions, transplant real-time operating system into ARM, design the driver of the peripheral assisted chip, develop the application program to control and configuration of FPGA, design IP core of logic algorithm for various NC motion control to configured it into FPGA. The whole control system uses the concept of modular and structured design to develop hardware and software system. Thus the NC motion controller with the advantage of easily tailoring, highly opening, reconfigurable, and expandable can be implemented.
Taking a Comprehensive Approach to Common Core Rollout
ERIC Educational Resources Information Center
Illingworth, Amy
2016-01-01
One district, South Bay Union School District, devises and executes a comprehensive strategy that includes training for district staff, teachers and coaches, including using PLCs and professional development in the implementation of Common Core English language arts standards.
Heuristics for Scientific Experimentation: A Developmental Study.
ERIC Educational Resources Information Center
Klahr, David; And Others
1993-01-01
Studied developmental differences in the search constraint heuristics used in scientific reasoning using 12 undergraduates, 20 community college students, 17 fifth to seventh graders (grade 6), and 15 third graders taught to use a programmable robot. Adults use domain-general skills that go beyond the logic of confirmation and disconfirmation.…
2010-03-01
allows the programmer to use the English language in an expressive manor while still maintaining the logical structure of a programming language ( Pressman ...and Choudhury Tanzeem. 2000. Face Recognition for Smart Environments, IEEE Computer, pp. 50–55. Pressman , Roger. 2010. Software Engineering A
[The improved design of table operating box of digital subtraction angiography device].
Qi, Xianying; Zhang, Minghai; Han, Fengtan; Tang, Feng; He, Lemin
2009-12-01
In this paper are analyzed the disadvantages of CGO-3000 digital subtraction angiography table Operating Box. The authors put forward a communication control scheme between single-chip microcomputer(SCM) and programmable logic controller(PLC). The details of hardware and software of communication are given.
Electromechanical Devices and Controllers. Electronics Module 10. Instructor's Guide.
ERIC Educational Resources Information Center
Carter, Ed
This module is the tenth of 10 modules in the competency-based electronics series. Introductory materials include a listing of competencies addressed in the module, a parts/equipment list, and a cross-reference table of instructional materials. Six instructional units cover: electromechanical control devices; programmable logic controllers (PLC);…
The Programmable Calculator in the Classroom.
ERIC Educational Resources Information Center
Stolarz, Theodore J.
The uses of programable calculators in the mathematics classroom are presented. A discussion of the "microelectronics revolution" that has brought programable calculators into our society is also included. Pointed out is that the logical or mental processes used to program the programable calculator are identical to those used to program…
Towards Quantifying Programmable Logic Controller Resilience Against Intentional Exploits
2012-03-22
may improve the SCADA system’s resilience against DoS and man-in-the-middle ( MITM ) attacks. DoS attacks may be mitigated by using the redundant...paths available on the network links. MITM attacks may be mitigated by the data integrity checks associated with the middleware. Figure 4 illustrates
Three In-Course Assessment Reforms to Improve Higher Education Learning Outcomes
ERIC Educational Resources Information Center
Sadler, D. Royce
2016-01-01
A current international concern is that, for too large a proportion of graduates, their higher order cognitive and practical capabilities are below acceptable levels. The constituent courses of academic programmes are the most logical sites for developing these capabilities. Contributing to patchy attainment are deficiencies in three particular…
Jefferds, Maria Elena D; Flores-Ayala, Rafael
2015-12-01
Lack of monitoring capacity is a key barrier for nutrition interventions and limits programme management, decision making and programme effectiveness in many low-income and middle-income countries. A 2011 global assessment reported lack of monitoring capacity was the top barrier for home fortification interventions, such as micronutrient powders or lipid-based nutrient supplements. A Manual for Developing and Implementing Monitoring Systems for Home Fortification Interventions was recently disseminated. It is comprehensive and describes monitoring concepts and frameworks and includes monitoring tools and worksheets. The monitoring manual describes the steps of developing and implementing a monitoring system for home fortification interventions, including identifying and engaging stakeholders; developing a programme description including logic model and logical framework; refining the purpose of the monitoring system, identifying users and their monitoring needs; describing the design of the monitoring system; developing indicators; describing the core components of a comprehensive monitoring plan; and considering factors related to stage of programme development, sustainability and scale up. A fictional home fortification example is used throughout the monitoring manual to illustrate these steps. The monitoring manual is a useful tool to support the development and implementation of home fortification intervention monitoring systems. In the context of systematic capacity gaps to design, implement and monitor nutrition interventions in many low-income and middle-income countries, the dissemination of new tools, such as monitoring manuals may have limited impact without additional attention to strengthening other individual, organisational and systems levels capacities. Published 2014. This article is a U.S. Government work and is in the public domain in the USA.
Ge, Lei; Wang, Wenxiao; Sun, Ximei; Hou, Ting; Li, Feng
2016-10-04
Herein, a novel universal and label-free homogeneous electrochemical platform is demonstrated, on which a complete set of DNA-based two-input Boolean logic gates (OR, NAND, AND, NOR, INHIBIT, IMPLICATION, XOR, and XNOR) is constructed by simply and rationally deploying the designed DNA polymerization/nicking machines without complicated sequence modulation. Single-stranded DNA is employed as the proof-of-concept target/input to initiate or prevent the DNA polymerization/nicking cyclic reactions on these DNA machines to synthesize numerous intact G-quadruplex sequences or binary G-quadruplex subunits as the output. The generated output strands then self-assemble into G-quadruplexes that render remarkable decrease to the diffusion current response of methylene blue and, thus, provide the amplified homogeneous electrochemical readout signal not only for the logic gate operations but also for the ultrasensitive detection of the target/input. This system represents the first example of homogeneous electrochemical logic operation. Importantly, the proposed homogeneous electrochemical logic gates possess the input/output homogeneity and share a constant output threshold value. Moreover, the modular design of DNA polymerization/nicking machines enables the adaptation of these homogeneous electrochemical logic gates to various input and output sequences. The results of this study demonstrate the versatility and universality of the label-free homogeneous electrochemical platform in the design of biomolecular logic gates and provide a potential platform for the further development of large-scale DNA-based biocomputing circuits and advanced biosensors for multiple molecular targets.
NASA Technical Reports Server (NTRS)
Metcalfe, A. G.; Bodenheimer, R. E.
1976-01-01
A parallel algorithm for counting the number of logic-l elements in a binary array or image developed during preliminary investigation of the Tse concept is described. The counting algorithm is implemented using a basic combinational structure. Modifications which improve the efficiency of the basic structure are also presented. A programmable Tse computer structure is proposed, along with a hardware control unit, Tse instruction set, and software program for execution of the counting algorithm. Finally, a comparison is made between the different structures in terms of their more important characteristics.
Sequence invariant state machines
NASA Technical Reports Server (NTRS)
Whitaker, S.; Manjunath, S.
1990-01-01
A synthesis method and new VLSI architecture are introduced to realize sequential circuits that have the ability to implement any state machine having N states and m inputs, regardless of the actual sequence specified in the flow table. A design method is proposed that utilizes BTS logic to implement regular and dense circuits. A given state sequence can be programmed with power supply connections or dynamically reallocated if stored in a register. Arbitrary flow table sequences can be modified or programmed to dynamically alter the function of the machine. This allows VLSI controllers to be designed with the programmability of a general purpose processor but with the compact size and performance of dedicated logic.
Sequence-invariant state machines
NASA Technical Reports Server (NTRS)
Whitaker, Sterling R.; Manjunath, Shamanna K.; Maki, Gary K.
1991-01-01
A synthesis method and an MOS VLSI architecture are presented to realize sequential circuits that have the ability to implement any state machine having N states and m inputs, regardless of the actual sequence specified in the flow table. The design method utilizes binary tree structured (BTS) logic to implement regular and dense circuits. The desired state sequence can be hardwired with power supply connections or can be dynamically reallocated if stored in a register. This allows programmable VLSI controllers to be designed with a compact size and performance approaching that of dedicated logic. Results of ICV implementations are reported and an example sequence-invariant state machine is contrasted with implementations based on traditional methods.
Cryogenic Controls for Fermilab's Srf Cavities and Test Facility
NASA Astrophysics Data System (ADS)
Norris, B.; Bossert, R.; Klebaner, A.; Lackey, S.; Martinez, A.; Pei, L.; Soyars, W.; Sirotenko, V.
2008-03-01
A new superconducting radio frequency (SRF) cavities test facility is now operational at Fermilab's Meson Detector Building (MDB). The Cryogenic Test Facility (CTF), located in a separate building 500 m away, supplies the facility with cryogens. The design incorporates ambient temperature pumping for superfluid helium production, as well as three 0.6 kW at 4.5 K refrigerators, five screw compressors, a helium purifier, helium and nitrogen inventory, cryogenic distribution system, and a variety of test cryostats. To control and monitor the vastly distributed cryogenic system, a flexible scheme has been developed. Both commercial and experimental physics tools are used. APACS+™, a process automation control system from Siemens-Moore, is at the heart of the design. APACS+™ allows engineers to configure an ever evolving test facility while maintaining control over the plant and distribution system. APACS+™ nodes at CTF and MDB are coupled by a fiber optic network. DirectLogic205 PLCs by KOYO® are used as the field level interface to most I/O. The top layer of this system uses EPICS (Experimental Physics and Industrial Control System) as a SCADA/HMI. Utilities for graphical display, control loop setting, real time/historical plotting and alarming have been implemented by using the world-wide library of applications for EPICS. OPC client/server technology is used to bridge across each different platform. This paper presents this design and its successful implementation.
[National health resources for highly specialised medicine].
Bratlid, Dag; Rasmussen, Knut
2005-11-03
In order to monitor quality and efficiency in the use of health resources for highly specialised medicine, a National Professional Council has since 1990 advised the Norwegian health authorities on the establishing and localisation of such services. A comprehensive review of both the quality, economy and the geographical distribution of patients in each specialised service has been carried out. 33 defined national programmes were centralised to one hospital only and distributed among seven university hospitals. Eight multiregional programmes were centralised to two hospitals only and included four university hospitals. In 2001, a total of 2711 new patients were treated in these programmes. The system seems to have secured a sufficient patient flow to each programme so as to maintain quality. However, a geographically skewed distribution of patients was noted, particularly in some of the national programmes. In a small country like Norway, with 4.5 million inhabitants, a centralised monitoring of highly specialised medicine seems both rational and successful. By the same logic, however, international cooperation should probably be sought for the smallest patient groups.
NASA Astrophysics Data System (ADS)
Barrett, Timothy J.
In 2009, ASTM and AASHTO permitted the use of up to 5% interground limestone in ordinary portland cement (OPC) as a part of a change to ASTM C150/AASHTO M85. When this work was initiated a new proposal was being discussed that would enable up to 15% interground limestone cement to be considered in ASTM C595/AASHTO M234. This work served to provide rapid feedback to the state department of transportation and concrete industry for use in discussions regarding these specifications. Since the time this work was initiated, ASTM C595/AASHTO M234 was passed (2012c) and PLCs are now able to be specified, however they are still not widely used. The proposal for increasing the volume of limestone that would be permitted to be interground in cement is designed to enable more sustainable construction, which may significantly reduce the CO2 that is embodied in the built infrastructure while also extending the life of cement quarries. Research regarding the performance of cements with interground limestone has been conducted by the cement industry since these cements became widely used in Europe over three decades ago, however this work focuses on North American Portland Limestone Cements (PLCs) which are specifically designed to achieve similar performance as the OPCs they replace.This thesis presents a two-phase study in which the potential for application of cements containing limestone was assessed. The first phase of this study utilized a fundamental approach to determine whether cement with up to 15% of interground or blended limestone can be used as a direct substitute to ordinary portland cement. The second phase of the study assessed the concern of early age shrinkage and cracking potential when using PLCs, as these cements are typically ground finer than their OPC counterparts. For the first phase of the study, three commercially produced PLCs were obtained and compared to three commercially produced OPCs made from the same clinker. An additional cement was tested where the limestone was blended (i.e., not interground) as needed, enabling variation of the size of the limestone particles. In addition, one of the commercially produced OPCs and PLCs were used with fly ash. A series of standardized tests were run to assess the physical effects of intergrinding limestone in portland cement, the effect of limestone presence and method of inclusion on the hydration reaction, and the associated mechanical and transport properties of concretes made with these limestone cements. The second phase of the study used a commercially produced OPC, a PLC, and a PLC-slag all made from the same parent clinker to quantify the early age shrinkage and cracking potential. The study presents a series of tests that quantify the fundamental origins of shrinkage in cementitious materials to elucidate the differences between PLC and OPC. The bulk shrinkage of these systems is then quantified under free and restrained conditions to provide an assessment of the susceptibility for cracking in portland limestone cements. The results of the first phase of this thesis showed that in general the PLC and OPC systems have similar hydration, set, and mechanical performance. Transport properties in this study show behavior that is +/- 30% of the conventional OPC system depending on the system. Literature has shown similar freeze-thaw resistance when these materials are used in properly air entrained mixtures, and the results for PLC systems with fly ash show added performance. Based on these results it appears that PLC that meets ASTM C595/AASHTO M234 should be able to be used interchangeably with OPC, while it should also be noted that the investigation of the influence of salts and sulfates on PLCs is still ongoing and should be monitored. The results of the second phase of this thesis showed that while the PLCs are finer, this comes primarily by reducing the very large particles (clinker particles greater than 30 microns) using advanced separator technology and increasing the number of very fine limestone particles. This results in the cements tested having similar autogenous shrinkage development in the PLC systems compared to the OPC, with slightly less shrinkage in the PLC-slag system. The stress that develops when this shrinkage is restrained is very similar in comparing the OPC, PLC and PLC-slag systems and the PLC mixture tends to crack at a similar or slightly earlier times.
Logic Gate Operation by DNA Translocation through Biological Nanopores.
Yasuga, Hiroki; Kawano, Ryuji; Takinoue, Masahiro; Tsuji, Yutaro; Osaki, Toshihisa; Kamiya, Koki; Miki, Norihisa; Takeuchi, Shoji
2016-01-01
Logical operations using biological molecules, such as DNA computing or programmable diagnosis using DNA, have recently received attention. Challenges remain with respect to the development of such systems, including label-free output detection and the rapidity of operation. Here, we propose integration of biological nanopores with DNA molecules for development of a logical operating system. We configured outputs "1" and "0" as single-stranded DNA (ssDNA) that is or is not translocated through a nanopore; unlabeled DNA was detected electrically. A negative-AND (NAND) operation was successfully conducted within approximately 10 min, which is rapid compared with previous studies using unlabeled DNA. In addition, this operation was executed in a four-droplet network. DNA molecules and associated information were transferred among droplets via biological nanopores. This system would facilitate linking of molecules and electronic interfaces. Thus, it could be applied to molecular robotics, genetic engineering, and even medical diagnosis and treatment.
Bi, Sai; Chen, Min; Jia, Xiaoqiang; Dong, Ying; Wang, Zonghua
2015-07-06
A hyper-branched hybridization chain reaction (HB-HCR) is presented herein, which consists of only six species that can metastably coexist until the introduction of an initiator DNA to trigger a cascade of hybridization events, leading to the self-sustained assembly of hyper-branched and nicked double-stranded DNA structures. The system can readily achieve ultrasensitive detection of target DNA. Moreover, the HB-HCR principle is successfully applied to construct three-input concatenated logic circuits with excellent specificity and extended to design a security-mimicking keypad lock system. Significantly, the HB-HCR-based keypad lock can alarm immediately if the "password" is incorrect. Overall, the proposed HB-HCR with high amplification efficiency is simple, homogeneous, fast, robust, and low-cost, and holds great promise in the development of biosensing, in the programmable assembly of DNA architectures, and in molecular logic operations. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Logical NAND and NOR Operations Using Algorithmic Self-assembly of DNA Molecules
NASA Astrophysics Data System (ADS)
Wang, Yanfeng; Cui, Guangzhao; Zhang, Xuncai; Zheng, Yan
DNA self-assembly is the most advanced and versatile system that has been experimentally demonstrated for programmable construction of patterned systems on the molecular scale. It has been demonstrated that the simple binary arithmetic and logical operations can be computed by the process of self assembly of DNA tiles. Here we report a one-dimensional algorithmic self-assembly of DNA triple-crossover molecules that can be used to execute five steps of a logical NAND and NOR operations on a string of binary bits. To achieve this, abstract tiles were translated into DNA tiles based on triple-crossover motifs. Serving as input for the computation, long single stranded DNA molecules were used to nucleate growth of tiles into algorithmic crystals. Our method shows that engineered DNA self-assembly can be treated as a bottom-up design techniques, and can be capable of designing DNA computer organization and architecture.
Three challenges to the complementarity of the logic and the pragmatics of science.
Uebel, Thomas
2015-10-01
The bipartite metatheory thesis attributes to Rudolf Carnap, Philipp Frank and Otto Neurath a conception of the nature of post-metaphysical philosophy of science that sees the purely formal-logical analyses of the logic of science as complemented by empirical inquiries into the psychology, sociology and history of science. Three challenges to this thesis are considered in this paper: that Carnap did not share this conception of the nature of philosophy of science even on a programmatic level, that Carnap's detailed analysis of the language of science is incompatible with one developed by Neurath for the pursuit of empirical studies of science, and, finally, that Neurath himself was confused about the programme of which the bipartite metatheory thesis makes him a representative. I argue that all three challenges can be met and refuted. Copyright © 2015 Elsevier Ltd. All rights reserved.
Logic Gate Operation by DNA Translocation through Biological Nanopores
Takinoue, Masahiro; Tsuji, Yutaro; Osaki, Toshihisa; Kamiya, Koki; Miki, Norihisa; Takeuchi, Shoji
2016-01-01
Logical operations using biological molecules, such as DNA computing or programmable diagnosis using DNA, have recently received attention. Challenges remain with respect to the development of such systems, including label-free output detection and the rapidity of operation. Here, we propose integration of biological nanopores with DNA molecules for development of a logical operating system. We configured outputs “1” and “0” as single-stranded DNA (ssDNA) that is or is not translocated through a nanopore; unlabeled DNA was detected electrically. A negative-AND (NAND) operation was successfully conducted within approximately 10 min, which is rapid compared with previous studies using unlabeled DNA. In addition, this operation was executed in a four-droplet network. DNA molecules and associated information were transferred among droplets via biological nanopores. This system would facilitate linking of molecules and electronic interfaces. Thus, it could be applied to molecular robotics, genetic engineering, and even medical diagnosis and treatment. PMID:26890568
DOE Office of Scientific and Technical Information (OSTI.GOV)
Nishimura, Takahiro, E-mail: t-nishimura@ist.osaka-u.ac.jp; Fujii, Ryo; Ogura, Yusuke
Molecular logic circuits represent a promising technology for observation and manipulation of biological systems at the molecular level. However, the implementation of molecular logic circuits for temporal and programmable operation remains challenging. In this paper, we demonstrate an optically controllable logic circuit that uses fluorescence resonance energy transfer (FRET) for signaling. The FRET-based signaling process is modulated by both molecular and optical inputs. Based on the distance dependence of FRET, the FRET pathways required to execute molecular logic operations are formed on a DNA nanostructure as a circuit based on its molecular inputs. In addition, the FRET pathways on themore » DNA nanostructure are controlled optically, using photoswitching fluorescent molecules to instruct the execution of the desired operation and the related timings. The behavior of the circuit can thus be controlled using external optical signals. As an example, a molecular logic circuit capable of executing two different logic operations was studied. The circuit contains functional DNAs and a DNA scaffold to construct two FRET routes for executing Input 1 AND Input 2 and Input 1 AND NOT Input 3 operations on molecular inputs. The circuit produced the correct outputs with all possible combinations of the inputs by following the light signals. Moreover, the operation execution timings were controlled based on light irradiation and the circuit responded to time-dependent inputs. The experimental results demonstrate that the circuit changes the output for the required operations following the input of temporal light signals.« less
A Remote Laboratory Platform for Electrical Drive Control Using Programmable Logic Controllers
ERIC Educational Resources Information Center
Ferrater-Simon, C.; Molas-Balada, L.; Gomis-Bellmunt, O.; Lorenzo-Martinez, N.; Bayo-Puxan, O.; Villafafila-Robles, R.
2009-01-01
Many teaching institutions worldwide are working on distance learning applications. In this field, remote laboratories are enabling intensive use of university facilities, while aiding the work of professors and students. The present paper introduces a platform designed to be used in industrial automation practical work. The platform is…
2007-08-01
with a Design Specification de- scribed by Scilab [26], a MATLAB-like software applica- tion, and ends up with HDL code. The Design Specifica- tion...Conf. on Field Programmable Logic and Applications (FPL’05), Tampere, Finland, pp. 118–123, Aug. 2005. [26] Scilab 3.0, INRIA-ENPC, France, http
USDA-ARS?s Scientific Manuscript database
Control of dissolved gases, especially oxygen is an essential component of recirculating aquaculture systems. The use of pure oxygen in a recirculating aquaculture system creates supersaturated concentrations of dissolved oxygen and can reduce fish production costs by supporting greater fish and fee...
ERIC Educational Resources Information Center
Foord, Kathleen A.; Haar, Jean M.
2012-01-01
Books by education experts and speakers at national professional conferences have inspired many school leaders to initiate professional learning communities (PLCs). Sustaining them effectively to raise student achievement is another matter. How can one know whether a PLC is moving toward a desired outcome? Measuring effectiveness requires an…
A self-timed multipurpose delay sensor for Field Programmable Gate Arrays (FPGAs).
Osuna, Carlos Gómez; Ituero, Pablo; López-Vallejo, Marisa
2013-12-20
This paper presents a novel self-timed multi-purpose sensor especially conceived for Field Programmable Gate Arrays (FPGAs). The aim of the sensor is to measure performance variations during the life-cycle of the device, such as process variability, critical path timing and temperature variations. The proposed topology, through the use of both combinational and sequential FPGA elements, amplifies the time of a signal traversing a delay chain to produce a pulse whose width is the sensor's measurement. The sensor is fully self-timed, avoiding the need for clock distribution networks and eliminating the limitations imposed by the system clock. One single off- or on-chip time-to-digital converter is able to perform digitization of several sensors in a single operation. These features allow for a simplified approach for designers wanting to intertwine a multi-purpose sensor network with their application logic. Employed as a temperature sensor, it has been measured to have an error of ±0.67 °C, over the range of 20-100 °C, employing 20 logic elements with a 2-point calibration.
A Self-Timed Multipurpose Delay Sensor for Field Programmable Gate Arrays (FPGAs)
Osuna, Carlos Gómez; Ituero, Pablo; López-Vallejo, Marisa
2014-01-01
This paper presents a novel self-timed multi-purpose sensor especially conceived for Field Programmable Gate Arrays (FPGAs). The aim of the sensor is to measure performance variations during the life-cycle of the device, such as process variability, critical path timing and temperature variations. The proposed topology, through the use of both combinational and sequential FPGA elements, amplifies the time of a signal traversing a delay chain to produce a pulse whose width is the sensor's measurement. The sensor is fully self-timed, avoiding the need for clock distribution networks and eliminating the limitations imposed by the system clock. One single off- or on-chip time-to-digital converter is able to perform digitization of several sensors in a single operation. These features allow for a simplified approach for designers wanting to intertwine a multi-purpose sensor network with their application logic. Employed as a temperature sensor, it has been measured to have an error of ±0.67 °C, over the range of 20–100 °C, employing 20 logic elements with a 2-point calibration. PMID:24361927
A distributed control system for the lower-hybrid current drive system on the Tokamak de Varennes
NASA Astrophysics Data System (ADS)
Bagdoo, J.; Guay, J. M.; Chaudron, G.-A.; Decoste, R.; Demers, Y.; Hubbard, A.
1990-08-01
An rf current drive system with an output power of 1 MW at 3.7 GHz is under development for the Tokamak de Varennes. The control system is based on an Ethernet local-area network of programmable logic controllers as front end, personal computers as consoles, and CAMAC-based DSP processors. The DSP processors ensure the PID control of the phase and rf power of each klystron, and the fast protection of high-power rf hardware, all within a 40 μs loop. Slower control and protection, event sequencing and the run-time database are provided by the programmable logic controllers, which communicate, via the LAN, with the consoles. The latter run a commercial process-control console software. The LAN protocol respects the first four layers of the ISO/OSI 802.3 standard. Synchronization with the tokamak control system is provided by commercially available CAMAC timing modules which trigger shot-related events and reference waveform generators. A detailed description of each subsystem and a performance evaluation of the system will be presented.
Photonic Programmable Tele-Cloning Network.
Li, Wei; Chen, Ming-Cheng
2016-06-29
The concept of quantum teleportation allows an unknown quantum states to be broadcasted and processed in a distributed quantum network. The quantum information injected into the network can be diluted to distant multi-copies by quantum cloning and processed by arbitrary quantum logic gates which were programed in advance in the network quantum state. A quantum network combines simultaneously these fundamental quantum functions could lead to new intriguing applications. Here we propose a photonic programmable telecloning network based on a four-photon interferometer. The photonic network serves as quantum gate, quantum cloning and quantum teleportation and features experimental advantage of high brightness by photon recycling.
NASA Technical Reports Server (NTRS)
Haley, D. C.; Almand, B. J.; Thomas, M. M.; Krauze, L. D.; Gremban, K. D.; Sanborn, J. C.; Kelly, J. H.; Depkovich, T. M.
1984-01-01
The purpose of the Robotics Simulation (ROBSIM) program is to provide a broad range of computer capabilities to assist in the design, verification, simulation, and study of robotic systems. ROBSIM is programmed in FORTRAN 77 and implemented on a VAX 11/750 computer using the VMS operating system. This programmer's guide describes the ROBSIM implementation and program logic flow, and the functions and structures of the different subroutines. With this manual and the in-code documentation, and experienced programmer can incorporate additional routines and modify existing ones to add desired capabilities.
Multiprog virtual laboratory applied to PLC programming learning
NASA Astrophysics Data System (ADS)
Shyr, Wen-Jye
2010-10-01
This study develops a Multiprog virtual laboratory for a mechatronics education designed to teach how to programme a programmable logic controller (PLC). The study was carried out with 34 students in the Department of Industry Education and Technology at National Changhua University of Education in Taiwan. In total, 17 students were assigned to each group, experimental and control. Two laboratory exercises were designed to provide students with experience in PLC programming. The results show that the experiments supported by Multiprog virtual laboratory user-friendly control interfaces generate positive meaningful results in regard to students' knowledge and understanding of the material.
Global Systems Science and Hands-On Universe Course Materials for High School
NASA Astrophysics Data System (ADS)
Gould, A.
2011-09-01
The University of California Berkeley's Lawrence Hall of Science has a project called Global Systems Science (GSS). GSS produced a set of course materials for high school science education that includes reading materials, investigations, and software for analyzing satellite images of Earth focusing on Earth systems as well as societal issues that require interdisciplinary science for full understanding. The software has general application in analysis of any digital images for a variety of purposes. NSF and NASA funding have contributed to the development of GSS. The current NASA-funded project of GSS is Lifelines for High School Climate Change Education (LHSCCE), which aims to establish professional learning communities (PLCs) to share curriculum resources and best practices for teaching about climate change in grades 9-12. The project explores ideal ways for teachers to meet either in-person or using simple yet effective distance-communication techniques (tele-meetings), depending on local preferences. Skills promoted include: how to set up a website to share resources; initiating tele-meetings with any available mechanism (webinars, Skype, telecons, moodles, social network tools, etc.); and easy ways of documenting and archiving presentations made at meetings. Twenty teacher leaders are forming the PLCs in their regions or districts. This is a national effort in which teachers share ideas, strategies, and resources aimed at making science education relevant to societal issues, improve students' understanding of climate change issues, and contribute to possible solutions. Although the binding theme is climate change, the application is to a wide variety of courses: Earth science, environmental science, biology, physics, and chemistry. Moreover, the PLCs formed can last as long as the members find it useful and can deal with any topics of interest, even if they are only distantly related to climate change.
Kunrath-Lima, Marianna; de Miranda, Marcelo Coutinho; Ferreira, Andrea da Fonseca; Faraco, Camila Cristina Fraga; de Melo, Mariane Izabella Abreu; Goes, Alfredo Miranda; Rodrigues, Michele Angela; Faria, Jerusa Araújo Quintão Arantes; Gomes, Dawidson Assis
2018-06-01
Ca 2+ is an important second messenger, and it is involved in many cellular processes such as cell death and proliferation. The rise in intracellular Ca 2+ levels can be due to the generation of inositol 1,4,5-trisphosphate (InsP 3 ), which is a product of phosphatidylinositol 4,5-bisphosphate (PIP 2 ) hydrolysis by phospholipases C (PLCs), that leads to Ca 2+ release from endoplasmic reticulum by InsP 3 receptors (InsP 3 R). Ca 2+ signaling patterns can vary in different regions of the cell and increases in nuclear Ca 2+ levels have specific biological effects that differ from those of Ca 2+ increase in the cytoplasm. There are PLCs in the cytoplasm and nucleus, but little is known about the functions of nuclear PLCs. This work aimed to characterize phenotypically the human PLCδ4 (hPLCδ4) in mesenchymal stem cells. This nuclear isoform of PLC is present in different cell types and has a possible role in proliferative processes. In this work, hPLCδ4 was found to be mainly nuclear in human adipose-derived mesenchymal stem cells (hASC). PLCδ4 knockdown demonstrated that it is essential for hASC proliferation, without inducing cell death. An increase of cells in G1, and a reduction of cells on interphase and G2/M in knockdown cells were seen. Furthermore, PLCδ4 knockdown increased the percentage of senescent cells, p16 INK4A+ and p21 Cip1 mRNAs expression, which could explain the impaired cell proliferation. The results show that hPLCδ4 is in involved in cellular proliferation and senescence in hASC. Copyright © 2018 Elsevier Inc. All rights reserved.
Ting, Joseph Y; Resende, Maura; More, Kiran; Nicholls, Donna; Weisz, Dany E; El-Khuffash, Afif; Jain, Amish; McNamara, Patrick J
2016-08-01
The postoperative course of preterm babies undergoing surgical closure of a patent ductus arteriosus (PDA) is often complicated by postligation cardiac syndrome (PLCS). Despite targeted milrinone prophylaxis, some infants continue to experience postoperative respiratory deterioration. Our objective is to describe the immediate postoperative course and identify risk factors for respiratory instability when preterm infants undergoing PDA ligation are managed with targeted milrinone treatment. A retrospective review of a cohort of infants undergoing PDA ligation between January, 2010 and August, 2013 was conducted. All infants had a targeted neonatal echocardiogram performed 1 hour after surgery. Infants received prophylactic milrinone treatment if the left ventricular output was <200 mL/kg/min. The primary outcome measure was the development of respiratory instability within 24 hours of surgery. Multivariable logistic regression was performed to identify predictors of respiratory instability. Eighty-six infants with a median gestational age of 25 weeks (interquartile range [IQR], 24-26) and a birth weight of 740 g (IQR, 640-853) were included in this study. Forty-nine (57.0%) received milrinone prophylaxis. There were 44 (51.2%) infants who developed oxygenation or ventilation failure, and 7 (8.1%) neonates developed PLCS. Infants with longer isovolumic relaxation time (IVRT ≥30 milliseconds) were more likely to develop either oxygenation or ventilation failure. Although the incidence of PLCS has declined after the introduction of targeted milrinone prophylaxis, many preterm infants continue to develop respiratory instability after surgical ligation. In this population, diastolic dysfunction manifested by prolonged IVRT could be associated with an adverse postoperative respiratory course. Copyright © 2016 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.
NASA Astrophysics Data System (ADS)
Rankin, Drew J.; Jiang, Jin
2011-04-01
Verification and validation (V&V) of safety control system quality and performance is required prior to installing control system hardware within nuclear power plants (NPPs). Thus, the objective of the hardware-in-the-loop (HIL) platform introduced in this paper is to verify the functionality of these safety control systems. The developed platform provides a flexible simulated testing environment which enables synchronized coupling between the real and simulated world. Within the platform, National Instruments (NI) data acquisition (DAQ) hardware provides an interface between a programmable electronic system under test (SUT) and a simulation computer. Further, NI LabVIEW resides on this remote DAQ workstation for signal conversion and routing between Ethernet and standard industrial signals as well as for user interface. The platform is applied to the testing of a simplified implementation of Canadian Deuterium Uranium (CANDU) shutdown system no. 1 (SDS1) which monitors only the steam generator level of the simulated NPP. CANDU NPP simulation is performed on a Darlington NPP desktop training simulator provided by Ontario Power Generation (OPG). Simplified SDS1 logic is implemented on an Invensys Tricon v9 programmable logic controller (PLC) to test the performance of both the safety controller and the implemented logic. Prior to HIL simulation, platform availability of over 95% is achieved for the configuration used during the V&V of the PLC. Comparison of HIL simulation results to benchmark simulations shows good operational performance of the PLC following a postulated initiating event (PIE).
Yang, Bin; Zhang, Xiao-Bing; Kang, Li-Ping; Huang, Zhi-Mei; Shen, Guo-Li; Yu, Ru-Qin; Tan, Weihong
2014-08-07
DNA strand displacement cascades have been engineered to construct various fascinating DNA circuits. However, biological applications are limited by the insufficient cellular internalization of naked DNA structures, as well as the separated multicomponent feature. In this work, these problems are addressed by the development of a novel DNA nanodevice, termed intelligent layered nanoflare, which integrates DNA computing at the nanoscale, via the self-assembly of DNA flares on a single gold nanoparticle. As a "lab-on-a-nanoparticle", the intelligent layered nanoflare could be engineered to perform a variety of Boolean logic gate operations, including three basic logic gates, one three-input AND gate, and two complex logic operations, in a digital non-leaky way. In addition, the layered nanoflare can serve as a programmable strategy to sequentially tune the size of nanoparticles, as well as a new fingerprint spectrum technique for intelligent multiplex biosensing. More importantly, the nanoflare developed here can also act as a single entity for intracellular DNA logic gate delivery, without the need of commercial transfection agents or other auxiliary carriers. By incorporating DNA circuits on nanoparticles, the presented layered nanoflare will broaden the applications of DNA circuits in biological systems, and facilitate the development of DNA nanotechnology.
Understanding the Link between Professional Learning Communities and Teacher Collective Efficacy
ERIC Educational Resources Information Center
Voelkel, Robert H., Jr.; Chrispeels, Janet H.
2017-01-01
Research suggests effective professional learning communities (PLCs) enhance teacher collaboration and student achievement. Some studies indicate that these communities also predict greater collective efficacy, while others suggest teacher efficacy is predictive of teachers working together. Although studies have identified effective,…
Relations among Resources in Professional Learning Communities and Learning Outcomes
ERIC Educational Resources Information Center
Christ, Tanya; Arya, Poonam; Chiu, Ming Ming
2017-01-01
This study focused on two professional learning communities (PLCs) situated in literacy education practica courses. How four PLC resources (colleagues, facilitators, readings, and videos) were related to outcomes, including teachers' learning, teachers' application of this learning, and subsequent students' learning, was examined. Participants…
ERIC Educational Resources Information Center
McIntosh, Ronald D.
2008-01-01
Professional learning communities (PLCs) are designed to increase and improve the time teachers spend working with one another planning curriculum for mathematics, reading, writing, history, English, and other disciplines offered by their school. These meetings help to improve test scores in math and English. Teachers have coupled their subject…
Research and Policy: Can Online Learning Communities Foster Professional Development?
ERIC Educational Resources Information Center
Beach, Richard
2012-01-01
This column posits enhancing professional development through uses of digital tools to create professional learning communities (PLCs) designed to support collective inquiry and action research leading to schoolwide improvement. These digital tools include a social networking/discussion forum for teacher collaboration; teachers' individual…
NASA Astrophysics Data System (ADS)
Wang, Jinhong; Guan, Liang; Chapman, J.; Zhou, Bing; Zhu, Junjie
2017-11-01
We present a programmable time alignment scheme used in an ASIC for the ATLAS forward muon trigger development. The scheme utilizes regenerated clocks with programmable phases to compensate for the timing offsets introduced by different detector trace lengths. Each ASIC used in the design has 104 input channels with delay compensation circuitry providing steps of ∼3 ns and a full range of 25 ns for each channel. Detailed implementation of the scheme including majority logic to suppress single-event effects is presented. The scheme is flexible and fully synthesizable. The approach is adaptable to other applications with similar phase shifting requirements. In addition, the design is resource efficient and is suitable for cost-effective digital implementation with a large number of channels.
DNA "nano-claw": logic-based autonomous cancer targeting and therapy.
You, Mingxu; Peng, Lu; Shao, Na; Zhang, Liqin; Qiu, Liping; Cui, Cheng; Tan, Weihong
2014-01-29
Cell types, both healthy and diseased, can be classified by inventories of their cell-surface markers. Programmable analysis of multiple markers would enable clinicians to develop a comprehensive disease profile, leading to more accurate diagnosis and intervention. As a first step to accomplish this, we have designed a DNA-based device, called "Nano-Claw". Combining the special structure-switching properties of DNA aptamers with toehold-mediated strand displacement reactions, this claw is capable of performing autonomous logic-based analysis of multiple cancer cell-surface markers and, in response, producing a diagnostic signal and/or targeted photodynamic therapy. We anticipate that this design can be widely applied in facilitating basic biomedical research, accurate disease diagnosis, and effective therapy.
Bevan, Gwyn; Brown, Lawrence D
2014-07-01
This article considers how the 'accidental logics' of political settlements for the English National Health Service (NHS) and the Medicare and Medicaid programmes in the United States have resulted in different institutional arrangements and different implicit social contracts for rationing, which we define to be the denial of health care that is beneficial but is deemed to be too costly. This article argues that rationing is designed into the English NHS and designed out of US Medicare; and compares rationing for the elderly in the United States and in England for acute care, care at the end of life, and chronic care.
Institutional patterns in the Austrian space sector
NASA Astrophysics Data System (ADS)
Wong, Annie; Burg, Elco van; Giannopapa, Christina
2018-01-01
This paper employs the institutional logics perspective to understand how space policies and regulations influences entrepreneurship and innovation. We conducted interviews with entrepreneurs, ESA policy makers and governmental representatives in Austria and identified six prevailing institutional practices: geographical return, the SME-initiatives, the national support pattern, the size pattern, the consortium pattern and the experience pattern. Together, these patterns make up the semi-governmental logic of the space sector. We find that space actors adhere to these patterns to earn legitimacy, which is a condition for support and access to resources. This study adds to our understanding in the consequences of policies and contributes to the design of new space policies and programmes.
Hybrid CMOS/Molecular Integrated Circuits
NASA Astrophysics Data System (ADS)
Stan, M. R.; Rose, G. S.; Ziegler, M. M.
CMOS silicon technologies are likely to run out of steam in the next 10-15 years despite revolutionary advances in the past few decades. Molecular and other nanoscale technologies show significant promise but it is unlikely that they will completely replace CMOS, at least in the near term. This chapter explores opportunities for using CMOS and nanotechnology to enhance and complement each other in hybrid circuits. As an example of such a hybrid CMOS/nano system, a nanoscale programmable logic array (PLA) based on majority logic is described along with its supplemental CMOS circuitry. It is believed that such systems will be able to sustain the historical advances in the semiconductor industry while addressing manufacturability, yield, power, cost, and performance challenges.
Digital MOS integrated circuits
NASA Astrophysics Data System (ADS)
Elmasry, M. I.
MOS in digital circuit design is considered along with aspects of digital VLSI, taking into account a comparison of MOSFET logic circuits, 1-micrometer MOSFET VLSI technology, a generalized guide for MOSFET miniaturization, processing technologies, novel circuit structures for VLSI, and questions of circuit and system design for VLSI. MOS memory cells and circuits are discussed, giving attention to a survey of high-density dynamic RAM cell concepts, one-device cells for dynamic random-access memories, variable resistance polysilicon for high density CMOS Ram, high performance MOS EPROMs using a stacked-gate cell, and the optimization of the latching pulse for dynamic flip-flop sensors. Programmable logic arrays are considered along with digital signal processors, microprocessors, static RAMs, and dynamic RAMs.
Design on the x-ray oral digital image display card
NASA Astrophysics Data System (ADS)
Wang, Liping; Gu, Guohua; Chen, Qian
2009-10-01
According to the main characteristics of X-ray imaging, the X-ray display card is successfully designed and debugged using the basic principle of correlated double sampling (CDS) and combined with embedded computer technology. CCD sensor drive circuit and the corresponding procedures have been designed. Filtering and sampling hold circuit have been designed. The data exchange with PC104 bus has been implemented. Using complex programmable logic device as a device to provide gating and timing logic, the functions which counting, reading CPU control instructions, corresponding exposure and controlling sample-and-hold have been completed. According to the image effect and noise analysis, the circuit components have been adjusted. And high-quality images have been obtained.
2006-12-01
Specifi- cation described by Scilab [19], a MATLAB-like software, into HDL code. The Design Specification consists of a func- tion f (x), a domain over x...In- ter. Conf. on Field Programmable Logic and Applications (FPL’05), pp.118–123, Tampere, Finland, Aug. 2005. [19] Scilab 3.0, INRIA-ENPC, France
ERIC Educational Resources Information Center
Sérandour, Guillaume; Illanes, Alfredo; Maturana, Jorge; Cádiz, Janet
2016-01-01
Assessment is a notorious source of preoccupation for faculty and university governing bodies, especially when an institution initiates curricular reforms which shift the programme learning outcomes for knowledge to competencies. One obstacle to acceptance arises from a culture of quantitative assessment (often represented by a single mark), which…
USDA-ARS?s Scientific Manuscript database
In intensive recirculating aquaculture systems the use of supplemental oxygen, specifically pure liquid oxygen, increases the mass of fish that can be supported and eliminates oxygen as a major limiting factor to a system’s carrying capacity. The use of pure oxygen in a recirculating aquaculture sys...
ERIC Educational Resources Information Center
Tucker, James D.
This training module on the troubleshooting of an electromechanical system, The Westinghouse Programmable Logic Controller (PLC) controlling a pneumatic robot, is used for a troubleshooting unit in an electromechanical systems/robotics and automation systems course. In this unit, students locate and repair a defect in a PLC-operated machine. The…
1986-06-30
features of computer aided design systems and statistical quality control procedures that are generic to chip sets and processes. RADIATION HARDNESS -The...System PSP Programmable Signal Processor SSI Small Scale Integration ." TOW Tube Launched, Optically Tracked, Wire Guided TTL Transistor Transitor Logic
Advanced Ground Systems Maintenance Cryogenics Test Lab Control System Upgrade Project
NASA Technical Reports Server (NTRS)
Harp, Janice Leshay
2014-01-01
This project will outfit the Simulated Propellant Loading System (SPLS) at KSC's Cryogenics Test Laboratory with a new programmable logic control system. The control system upgrade enables the Advanced Ground Systems Maintenace Element Integration Team and other users of the SPLS to conduct testing in a controls environment similar to that used at the launch pad.
Barriers to Implementation of Effective Professional Learning Communities
ERIC Educational Resources Information Center
Kincaid, Eric R
2014-01-01
The implementation of professional learning communities (PLCs) in schools has been shown to increase the academic performance of students and develop a beneficial and productive culture of true teacher collaboration. Despite these demonstrated benefits, resistance to PLC implementation has been documented in various forms throughout the…
Collaborative Common Assessments: Teamwork. Instruction. Results.
ERIC Educational Resources Information Center
Erkens, Cassandra
2015-01-01
Explore the practical steps teacher teams must take to establish clear, comprehensive assessment systems that guide instruction and strengthen PLCs. This book has the capacity to reignite passion and energy assessment practices bring as tools to guide teaching and learning. Strengthen instructional agility in professional learning communities with…
A Step-by-Step Study of Formative Assessment
ERIC Educational Resources Information Center
Pietsch, Laura
2013-01-01
This article presents a guide to the development of formative assessments for school librarians participating in professional learning communities (PLC). It describes librarians' reading of assigned books, meeting with their PLCs, and incorporation of learned strategies in their daily instruction. Central library service readers' regular visits to…
Professional Learning Communities: The Emergence of Vulnerability
ERIC Educational Resources Information Center
Kelly, Jennifer
2013-01-01
This case study focuses on 11 individual teachers who participate in three distinct professional learning communities (PLCs) within one school. A PLC is "a group of people who take an active, reflective, collaborative, learning-orientated, and growth promoting approach toward the mysteries, problems, and perplexities of teaching and…
Factors That Develop Effective Professional Learning Communities in Taiwan
ERIC Educational Resources Information Center
Chen, Peiying; Lee, Che-Di; Lin, Hongda; Zhang, Chun-Xi
2016-01-01
This research aimed to investigate the key factors of developing effective professional learning communities (PLCs) within the Taiwanese context. Four constructs--supportive and shared leadership, shared visions, collegial trust, and shared practices--were adopted and developed into an instrument for measuring PLC function. A stratified random…
The 5 Habits of Effective PLCs
ERIC Educational Resources Information Center
Easton, Lois Brown
2015-01-01
This article describes the knowledge and skills that professional learning community members need to create a habit out of their desire. Habits serve educators as signposts of progress toward achieving their desires. They are interim indicators of a professional learning community's success. Ultimately, of course, professional learning communities…
2011-01-01
Background Information on the costs of implementing programmes designed to provide support of orphans and vulnerable children (OVC) in sub-Saharan Africa and elsewhere is increasingly being requested by donors for programme evaluation purposes. To date, little information exists to document the costs and structure of costs of OVC programmes as actually implemented "on the ground" by local non-governmental organizations (NGOs). This analysis provides a practical, six-step approach that NGOs can incorporate into routine operations to evaluate their costs of implementing their OVC programmes annually. This approach is applied to the Community-Based Care for Orphans and Vulnerable Children (CBCO) Program implemented by BIDII (a Kenyan NGO) in Eastern Province of Kenya. Methods and results The costing methodology involves the following six steps: accessing and organizing the NGO's annual financial report into logical sub-categories; reorganizing the sub-categories into input cost categories to create a financial cost profile; estimating the annual equivalent payment for programme equipment; documenting donations to the NGO for programme implementation; including a portion of NGO organizational costs not attributed to specific programmes; and including the results of Steps 3-5 into an expanded cost profile. Detailed results are provided for the CBCO programme. Conclusions This paper shows through a concrete example how NGOs implementing OVC programmes (and other public health programmes) can organize themselves for data collection and documentation prospectively during the implementation of their OVC programmes so that costing analyses become routine practice to inform programme implementation rather than a painful and flawed retrospective activity. Such information is required if the costs and outcomes achieved by OVC programmes will ever be clearly documented and compared across OVC programmes and other types of programmes (prevention, treatment, etc.). PMID:22182588
Larson, Bruce A; Wambua, Nancy
2011-12-19
Information on the costs of implementing programmes designed to provide support of orphans and vulnerable children (OVC) in sub-Saharan Africa and elsewhere is increasingly being requested by donors for programme evaluation purposes. To date, little information exists to document the costs and structure of costs of OVC programmes as actually implemented "on the ground" by local non-governmental organizations (NGOs). This analysis provides a practical, six-step approach that NGOs can incorporate into routine operations to evaluate their costs of implementing their OVC programmes annually. This approach is applied to the Community-Based Care for Orphans and Vulnerable Children (CBCO) Program implemented by BIDII (a Kenyan NGO) in Eastern Province of Kenya. The costing methodology involves the following six steps: accessing and organizing the NGO's annual financial report into logical sub-categories; reorganizing the sub-categories into input cost categories to create a financial cost profile; estimating the annual equivalent payment for programme equipment; documenting donations to the NGO for programme implementation; including a portion of NGO organizational costs not attributed to specific programmes; and including the results of Steps 3-5 into an expanded cost profile. Detailed results are provided for the CBCO programme. This paper shows through a concrete example how NGOs implementing OVC programmes (and other public health programmes) can organize themselves for data collection and documentation prospectively during the implementation of their OVC programmes so that costing analyses become routine practice to inform programme implementation rather than a painful and flawed retrospective activity. Such information is required if the costs and outcomes achieved by OVC programmes will ever be clearly documented and compared across OVC programmes and other types of programmes (prevention, treatment, etc.).
Examination of a Failed Professional Learning Community
ERIC Educational Resources Information Center
Sims, Rachel L.; Penny, G. Richard
2015-01-01
Schools are using various forms of professional learning communities (PLCs) in order to increase student achievement and improve educational practices through enhanced communication and collaboration among teachers. This study examined a PLC that had too narrow a focus and failed therefore to affect student achievement. A critical shortcoming of…
Evaluating the Implementation of Professional Learning Communities over Time
ERIC Educational Resources Information Center
Monceaux, Matthew C.
2017-01-01
Professional Learning Communities (PLCs) have become a popular reform initiative for schools looking to increase student achievement. School district officials can find it difficult to implement and sustain Professional Learning Communities as some teachers are not accustomed to the levels of collaboration with peers involved. If implemented and…
Professional Learning Communities in Singapore and Shanghai: Implications for Teacher Collaboration
ERIC Educational Resources Information Center
Hairon, Salleh; Tan, Charlene
2017-01-01
Professional learning communities (PLCs) have been recognised as having the potential to raise the quality of teachers, teaching and student learning through structured teacher collaboration, and have been featured prominently in Singapore and Shanghai--both considered top-performing Asian societies in the Program for International Student…
Problem Finding in Professional Learning Communities: A Learning Study Approach
ERIC Educational Resources Information Center
Tan, Yuen Sze Michelle; Caleon, Imelda Santos
2016-01-01
This study marries collaborative problem solving and learning study in understanding the onset of a cycle of teacher professional development process within school-based professional learning communities (PLCs). It aimed to explore how a PLC carried out collaborative problem finding--a key process involved in collaborative problem solving--that…
Launching Professional Learning Communities: Beginning Actions.
ERIC Educational Resources Information Center
Leo, Tara; Cowan, D'Ette
2000-01-01
A Professional Learning Community (PLC) is a school where administrators and teachers continuously seek and share learning to increase their effectiveness for students and act on what they learn. PLCs are characterized by five dimensions: shared and supportive leadership, shared values and vision, collective learning and application of learning,…
Professional Learning as a Predictor for Instructional Quality: A Secondary Analysis of TALIS
ERIC Educational Resources Information Center
Dogan, Selçuk; Yurtseven, Nihal
2018-01-01
The purpose of this study is to examine the effect of teachers' professional learning opportunities on instructional quality, which represents a combined approach of behaviorist, cognitivist, and constructivist principles in teaching. We incorporated professional learning communities (PLCs), professional development (PD) days, as well as 3 PD…
A Qualitative Study on Sustainable Professional Learning Communities in Catholic Elementary Schools
ERIC Educational Resources Information Center
Fernandez, Alexandra
2017-01-01
This qualitative study examined the elements of professional learning communities within Catholic elementary schools. The purpose of this study was to investigate best practices of Professional Learning Communities (PLCs) as reported by elementary principals in a random sample of Catholic elementary schools. The researcher interviewed 14…
Developing a Professional Learning Community
ERIC Educational Resources Information Center
Herrera, Charmaine M.
2012-01-01
Professional Learning Communties (PLCs) school reform movement that is grounded in decades of research. The purpose of this research was to investigate whether or not a PLC would help in cultivating a culture of learning and collaboration at a small charter school in Delaware. The research involved interviews of teachers, administrators and a data…
Critical and Transformative Practices in Professional Learning Communities
ERIC Educational Resources Information Center
Servage, Laura
2008-01-01
Professional learning communities (PLCs) have been held up as powerful structures for teachers' continuing professional development. In this work, the author has applied transformative learning theory to highlight the psychic risks of collaborative teacher learning, as well as the need for practical efforts to improve student learning--the means…
Earning "Dual Degrees": Black Bookstores as Alternative Knowledge Spaces
ERIC Educational Resources Information Center
Fisher, Maisha T.
2006-01-01
This article examines the role of two African American-owned and -operated bookstores in the literacy practices and education of their participants. Part of a larger ethnographic study of Participatory Literacy Communities (PLCs), this study shows how featured authors and audience participants considered these bookstores as both alternative and…
ERIC Educational Resources Information Center
Hewitt, Kimberly Kappler; Weckstein, Daniel K.
2012-01-01
One of the biggest obstacles to overcome in creating and sustaining an administrative professional learning community (PLC) is time. Administrators are constantly deluged by the tyranny of the urgent. It is a Herculean task to carve out time for PLCs, but it is imperative to do so. In this article, the authors describe how an administrative PLC…
Virtual PLC's @ Their Best: A Daily Diatribe
ERIC Educational Resources Information Center
Jaeger, Paige
2010-01-01
Years ago, working in isolation meant that to develop professionally, librarians had to read journals and wait for the two times per year there were librarian conferences locally, statewide, or nationally that would help them improve their program. Now colleagues, suggestions, and Professional Learning Communities (PLCs) are merely a click away.…
ERIC Educational Resources Information Center
Maag, John W.
2009-01-01
Many public schools currently have organizational structures that form barriers for dealing more effectively with students' challenging behaviors even though positive school-wide approaches exist and provide empirical support for their use. Nevertheless, resistance to change occurs at both institutional and individual levels. Improving student…
Sustaining Professional Learning Communities through Teacher Leadership
ERIC Educational Resources Information Center
Jennings, Karen
2013-01-01
Professional learning communities (PLCs), with their attributes of shared values, high expectations, and collaboration, have the potential to change school culture. The 4 elementary schools in this study have been unable to sustain ongoing, effective teamwork, resulting in a failure to attain adequate progress, and in 2 schools, in the placement…
Analyzing Learning in Professional Learning Communities: A Conceptual Framework
ERIC Educational Resources Information Center
Van Lare, Michelle D.; Brazer, S. David
2013-01-01
The purpose of this article is to build a conceptual framework that informs current understanding of how professional learning communities (PLCs) function in conjunction with organizational learning. The combination of sociocultural learning theories and organizational learning theories presents a more complete picture of PLC processes that has…
Organizational and Relational Factors in Professional Learning Communities
ERIC Educational Resources Information Center
Gray, Julie; Mitchell, Roxanne; Tarter, C. John
2014-01-01
The roles of organizational and relational factors in regard to professional learning communities (PLCs) have been investigated by many, yet none have considered enabling school structures, trust, and collective efficacy as variables. We take a deeper look at the formal or organizational aspects of the school represented by enabling school…
ERIC Educational Resources Information Center
Blitz, Cynthia L.; Schulman, Rebecca
2016-01-01
For more than a decade education practitioners have promoted the professional learning community (PLC) as an effective way to provide professional development to teachers. As more PLCs are established in schools and districts nationwide, education stakeholders--researchers, practitioners, administrators, and policymakers--are interested in…
Using Pipelined XNOR Logic to Reduce SEU Risks in State Machines
NASA Technical Reports Server (NTRS)
Le, Martin; Zheng, Xin; Katanyoutant, Sunant
2008-01-01
Single-event upsets (SEUs) pose great threats to avionic systems state machine control logic, which are frequently used to control sequence of events and to qualify protocols. The risks of SEUs manifest in two ways: (a) the state machine s state information is changed, causing the state machine to unexpectedly transition to another state; (b) due to the asynchronous nature of SEU, the state machine's state registers become metastable, consequently causing any combinational logic associated with the metastable registers to malfunction temporarily. Effect (a) can be mitigated with methods such as triplemodular redundancy (TMR). However, effect (b) cannot be eliminated and can degrade the effectiveness of any mitigation method of effect (a). Although there is no way to completely eliminate the risk of SEU-induced errors, the risk can be made very small by use of a combination of very fast state-machine logic and error-detection logic. Therefore, one goal of two main elements of the present method is to design the fastest state-machine logic circuitry by basing it on the fastest generic state-machine design, which is that of a one-hot state machine. The other of the two main design elements is to design fast error-detection logic circuitry and to optimize it for implementation in a field-programmable gate array (FPGA) architecture: In the resulting design, the one-hot state machine is fitted with a multiple-input XNOR gate for detection of illegal states. The XNOR gate is implemented with lookup tables and with pipelines for high speed. In this method, the task of designing all the logic must be performed manually because no currently available logic synthesis software tool can produce optimal solutions of design problems of this type. However, some assistance is provided by a script, written for this purpose in the Python language (an object-oriented interpretive computer language) to automatically generate hardware description language (HDL) code from state-transition rules.
Efficient G(sup 4)FET-Based Logic Circuits
NASA Technical Reports Server (NTRS)
Vatan, Farrokh
2008-01-01
A total of 81 optimal logic circuits based on four-gate field-effect transistors (G(sup 4)4FETs) have been designed to implement all Boolean functions of up to three variables. The purpose of this development was to lend credence to the expectation that logic circuits based on G(sup 4)FETs could be more efficient (in the sense that they could contain fewer transistors), relative to functionally equivalent logic circuits based on conventional transistors. A G(sup 4)FET a combination of a junction field-effect transistor (JFET) and a metal oxide/semiconductor field-effect transistor (MOSFET) superimposed in a single silicon island and can therefore be regarded as two transistors sharing the same body. A G(sup 4)FET can also be regarded as a single device having four gates: two side junction-based gates, a top MOS gate, and a back gate activated by biasing of a silicon-on-insulator substrate. Each of these gates can be used to control the conduction characteristics of the transistor; this possibility creates new options for designing analog, radio-frequency, mixed-signal, and digital circuitry. One such option is to design a G(sup 4)FET to function as a three-input NOT-majority gate, which has been shown to be a universal and programmable logic gate. Optimal NOT-majority-gate, G(sup 4)FET-based logic-circuit designs were obtained in a comparative study that also included formulation of functionally equivalent logic circuits based on NOR and NAND gates implemented by use of conventional transistors. In the study, the problem of finding the optimal design for each logic function and each transistor type was solved as an integer-programming optimization problem. Considering all 81 non-equivalent Boolean functions included in the study, it was found that in 63% of the cases, fewer logic gates (and, hence, fewer transistors) would be needed in the G(sup 4)FET-based implementations.
Pruttivarasin, Thaned; Katori, Hidetoshi
2015-11-01
We present a compact field-programmable gate array (FPGA) based pulse sequencer and radio-frequency (RF) generator suitable for experiments with cold trapped ions and atoms. The unit is capable of outputting a pulse sequence with at least 32 transistor-transistor logic (TTL) channels with a timing resolution of 40 ns and contains a built-in 100 MHz frequency counter for counting electrical pulses from a photo-multiplier tube. There are 16 independent direct-digital-synthesizers RF sources with fast (rise-time of ∼60 ns) amplitude switching and sub-mHz frequency tuning from 0 to 800 MHz.
Gich, Jordi; Freixenet, Jordi; Garcia, Rafael; Vilanova, Joan Carles; Genís, David; Silva, Yolanda; Montalban, Xavier; Ramió-Torrentà, Lluís
2015-09-01
Cognitive rehabilitation is often delayed in multiple sclerosis (MS). To develop a free and specific cognitive rehabilitation programme for MS patients to be used from early stages that does not interfere with daily living activities. MS-line!, cognitive rehabilitation materials consisting of written, manipulative and computer-based materials with difficulty levels developed by a multidisciplinary team. Mathematical, problem-solving and word-based exercises were designed. Physical materials included spatial, coordination and reasoning games. Computer-based material included logic and reasoning, working memory and processing speed games. Cognitive rehabilitation exercises that are specific for MS patients have been successfully developed. © The Author(s), 2014.
Photonic Programmable Tele-Cloning Network
Li, Wei; Chen, Ming-Cheng
2016-01-01
The concept of quantum teleportation allows an unknown quantum states to be broadcasted and processed in a distributed quantum network. The quantum information injected into the network can be diluted to distant multi-copies by quantum cloning and processed by arbitrary quantum logic gates which were programed in advance in the network quantum state. A quantum network combines simultaneously these fundamental quantum functions could lead to new intriguing applications. Here we propose a photonic programmable telecloning network based on a four-photon interferometer. The photonic network serves as quantum gate, quantum cloning and quantum teleportation and features experimental advantage of high brightness by photon recycling. PMID:27353838
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pruttivarasin, Thaned, E-mail: thaned.pruttivarasin@riken.jp; Katori, Hidetoshi; Innovative Space-Time Project, ERATO, JST, Bunkyo-ku, Tokyo 113-8656
We present a compact field-programmable gate array (FPGA) based pulse sequencer and radio-frequency (RF) generator suitable for experiments with cold trapped ions and atoms. The unit is capable of outputting a pulse sequence with at least 32 transistor-transistor logic (TTL) channels with a timing resolution of 40 ns and contains a built-in 100 MHz frequency counter for counting electrical pulses from a photo-multiplier tube. There are 16 independent direct-digital-synthesizers RF sources with fast (rise-time of ∼60 ns) amplitude switching and sub-mHz frequency tuning from 0 to 800 MHz.
Memristor-based programmable logic array (PLA) and analysis as Memristive networks.
Lee, Kwan-Hee; Lee, Sang-Jin; Kim, Seok-Man; Cho, Kyoungrok
2013-05-01
A Memristor theorized by Chua in 1971 has the potential to dramatically influence the way electronic circuits are designed. It is a two terminal device whose resistance state is based on the history of charge flow brought about as the result of the voltage being applied across its terminals and hence can be thought of as a special case of a reconfigurable resistor. Nanoscale devices using dense and regular fabrics such as Memristor cross-bar is promising new architecture for System-on-Chip (SoC) implementations in terms of not only the integration density that the technology can offer but also both improved performance and reduced power dissipation. Memristor has the capacity to switch between high and low resistance states in a cross-bar circuit configuration. The cross-bars are formed from an array of vertical conductive nano-wires cross a second array of horizontal conductive wires. Memristors are realized at the intersection of the two wires in the array through appropriate processing technology such that any particular wire in the vertical array can be connected to a wire in the horizontal array by switching the resistance of a particular intersection to a low state while other cross-points remain in a high resistance state. However the approach introduces a number of challenges. The lack of voltage gain prevents logic being cascaded and voltage level degradation affects robustness of the operation. Moreover the cross-bars introduce sneak current paths when two or more cross points are connected through the switched Memristor. In this paper, we propose Memristor-based programmable logic array (PLA) architecture and develop an analytical model to analyze the logic level on the memristive networks. The proposed PLA architecture has 12 inputs maximum and can be cascaded for more input variables with R(off)/R(on) ratio in the range from 55 to 160 of Memristors.
Development of Algorithms for Control of Humidity in Plant Growth Chambers
NASA Technical Reports Server (NTRS)
Costello, Thomas A.
2003-01-01
Algorithms were developed to control humidity in plant growth chambers used for research on bioregenerative life support at Kennedy Space Center. The algorithms used the computed water vapor pressure (based on measured air temperature and relative humidity) as the process variable, with time-proportioned outputs to operate the humidifier and de-humidifier. Algorithms were based upon proportional-integral-differential (PID) and Fuzzy Logic schemes and were implemented using I/O Control software (OPTO-22) to define and download the control logic to an autonomous programmable logic controller (PLC, ultimate ethernet brain and assorted input-output modules, OPTO-22), which performed the monitoring and control logic processing, as well the physical control of the devices that effected the targeted environment in the chamber. During limited testing, the PLC's successfully implemented the intended control schemes and attained a control resolution for humidity of less than 1%. The algorithms have potential to be used not only with autonomous PLC's but could also be implemented within network-based supervisory control programs. This report documents unique control features that were implemented within the OPTO-22 framework and makes recommendations regarding future uses of the hardware and software for biological research by NASA.
Auto-programmable impulse neural circuits
NASA Technical Reports Server (NTRS)
Watula, D.; Meador, J.
1990-01-01
Impulse neural networks use pulse trains to communicate neuron activation levels. Impulse neural circuits emulate natural neurons at a more detailed level than that typically employed by contemporary neural network implementation methods. An impulse neural circuit which realizes short term memory dynamics is presented. The operation of that circuit is then characterized in terms of pulse frequency modulated signals. Both fixed and programmable synapse circuits for realizing long term memory are also described. The implementation of a simple and useful unsupervised learning law is then presented. The implementation of a differential Hebbian learning rule for a specific mean-frequency signal interpretation is shown to have a straightforward implementation using digital combinational logic with a variation of a previously developed programmable synapse circuit. This circuit is expected to be exploited for simple and straightforward implementation of future auto-adaptive neural circuits.
Ikeda, Masato; Tanida, Tatsuya; Yoshii, Tatsuyuki; Kurotani, Kazuya; Onogi, Shoji; Urayama, Kenji; Hamachi, Itaru
2014-06-01
Soft materials that exhibit stimuli-responsive behaviour under aqueous conditions (such as supramolecular hydrogels composed of self-assembled nanofibres) have many potential biological applications. However, designing a macroscopic response to structurally complex biochemical stimuli in these materials still remains a challenge. Here we show that redox-responsive peptide-based hydrogels have the ability to encapsulate enzymes and still retain their activities. Moreover, cooperative coupling of enzymatic reactions with the gel response enables us to construct unique stimuli-responsive soft materials capable of sensing a variety of disease-related biomarkers. The programmable gel-sol response (even to biological samples) is visible to the naked eye. Furthermore, we built Boolean logic gates (OR and AND) into the hydrogel-enzyme hybrid materials, which were able to sense simultaneously plural specific biochemicals and execute a controlled drug release in accordance with the logic operation. The intelligent soft materials that we have developed may prove valuable in future medical diagnostics or treatments.
Engineered modular biomaterial logic gates for environmentally triggered therapeutic delivery
NASA Astrophysics Data System (ADS)
Badeau, Barry A.; Comerford, Michael P.; Arakawa, Christopher K.; Shadish, Jared A.; Deforest, Cole A.
2018-03-01
The successful transport of drug- and cell-based therapeutics to diseased sites represents a major barrier in the development of clinical therapies. Targeted delivery can be mediated through degradable biomaterial vehicles that utilize disease biomarkers to trigger payload release. Here, we report a modular chemical framework for imparting hydrogels with precise degradative responsiveness by using multiple environmental cues to trigger reactions that operate user-programmable Boolean logic. By specifying the molecular architecture and connectivity of orthogonal stimuli-labile moieties within material cross-linkers, we show selective control over gel dissolution and therapeutic delivery. To illustrate the versatility of this methodology, we synthesized 17 distinct stimuli-responsive materials that collectively yielded all possible YES/OR/AND logic outputs from input combinations involving enzyme, reductant and light. Using these hydrogels we demonstrate the first sequential and environmentally stimulated release of multiple cell lines in well-defined combinations from a material. We expect these platforms will find utility in several diverse fields including drug delivery, diagnostics and regenerative medicine.
KM3NeT Digital Optical Module electronics
NASA Astrophysics Data System (ADS)
Real, Diego
2016-04-01
The KM3NeT collaboration is currently building of a neutrino telescope with a volume of several cubic kilometres at the bottom of the Mediterranean Sea. The telescope consists of a matrix of Digital Optical Modules that will detect the Cherenkov light originated by the interaction of the neutrinos in the proximity of the detector. This contribution describes the main components of the read-out electronics of the Digital Optical Module: the Power Board, which delivers all the power supply required by the Digital Optical Molule electronics; the Central Logic Board, the main core of the read-out system, hosting 31 Time to Digital Converters with 1 ns resolution and the White Rabbit protocol embedded in the Central Logic Board Field Programmable Gate Array; the Octopus boards, that transfer the Low Voltage Digital Signals from the PMT bases to the Central Logic Board and finally the PMT bases, in charge of converting the analogue signal produced in the 31 3" PMTs into a Low Voltage Digital Signal.
NASA Astrophysics Data System (ADS)
Ikeda, Masato; Tanida, Tatsuya; Yoshii, Tatsuyuki; Kurotani, Kazuya; Onogi, Shoji; Urayama, Kenji; Hamachi, Itaru
2014-06-01
Soft materials that exhibit stimuli-responsive behaviour under aqueous conditions (such as supramolecular hydrogels composed of self-assembled nanofibres) have many potential biological applications. However, designing a macroscopic response to structurally complex biochemical stimuli in these materials still remains a challenge. Here we show that redox-responsive peptide-based hydrogels have the ability to encapsulate enzymes and still retain their activities. Moreover, cooperative coupling of enzymatic reactions with the gel response enables us to construct unique stimuli-responsive soft materials capable of sensing a variety of disease-related biomarkers. The programmable gel-sol response (even to biological samples) is visible to the naked eye. Furthermore, we built Boolean logic gates (OR and AND) into the hydrogel-enzyme hybrid materials, which were able to sense simultaneously plural specific biochemicals and execute a controlled drug release in accordance with the logic operation. The intelligent soft materials that we have developed may prove valuable in future medical diagnostics or treatments.
Engineered modular biomaterial logic gates for environmentally triggered therapeutic delivery.
Badeau, Barry A; Comerford, Michael P; Arakawa, Christopher K; Shadish, Jared A; DeForest, Cole A
2018-03-01
The successful transport of drug- and cell-based therapeutics to diseased sites represents a major barrier in the development of clinical therapies. Targeted delivery can be mediated through degradable biomaterial vehicles that utilize disease biomarkers to trigger payload release. Here, we report a modular chemical framework for imparting hydrogels with precise degradative responsiveness by using multiple environmental cues to trigger reactions that operate user-programmable Boolean logic. By specifying the molecular architecture and connectivity of orthogonal stimuli-labile moieties within material cross-linkers, we show selective control over gel dissolution and therapeutic delivery. To illustrate the versatility of this methodology, we synthesized 17 distinct stimuli-responsive materials that collectively yielded all possible YES/OR/AND logic outputs from input combinations involving enzyme, reductant and light. Using these hydrogels we demonstrate the first sequential and environmentally stimulated release of multiple cell lines in well-defined combinations from a material. We expect these platforms will find utility in several diverse fields including drug delivery, diagnostics and regenerative medicine.
Hussain, Mahmood Irtiza; Petrasiunas, Matthew Joseph; Bentley, Christopher D B; Taylor, Richard L; Carvalho, André R R; Hope, Joseph J; Streed, Erik W; Lobino, Mirko; Kielpinski, David
2016-07-25
Trapped ions are one of the most promising approaches for the realization of a universal quantum computer. Faster quantum logic gates could dramatically improve the performance of trapped-ion quantum computers, and require the development of suitable high repetition rate pulsed lasers. Here we report on a robust frequency upconverted fiber laser based source, able to deliver 2.5 ps ultraviolet (UV) pulses at a stabilized repetition rate of 300.00000 MHz with an average power of 190 mW. The laser wavelength is resonant with the strong transition in Ytterbium (Yb+) at 369.53 nm and its repetition rate can be scaled up using high harmonic mode locking. We show that our source can produce arbitrary pulse patterns using a programmable pulse pattern generator and fast modulating components. Finally, simulations demonstrate that our laser is capable of performing resonant, temperature-insensitive, two-qubit quantum logic gates on trapped Yb+ ions faster than the trap period and with fidelity above 99%.
NASA Technical Reports Server (NTRS)
Bains, R. W.; Herwig, H. A.; Luedeman, J. K.; Torina, E. M.
1974-01-01
The Shuttle Electric Power System (SEPS) computer program is considered in terms of the program manual, programmer guide, and program utilization. The main objective is to provide the information necessary to interpret and use the routines comprising the SEPS program. Subroutine descriptions including the name, purpose, method, variable definitions, and logic flow are presented.
ERIC Educational Resources Information Center
Fear, William J.
2007-01-01
This paper argues that the formulation of policy, at whatever level, to whatever scale or scope, is any different to the myriad of processes involved in strategic planning within and between organisations, and the attendant decision making processes that abound in such an environment (Hage, 1980; Hickson, 1987; Thompson, 1967; Weick, 1976). Those…
Firmware Counterfeiting and Modification Attacks on Programmable Logic Controllers
2013-03-01
86 5.4 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87 Appendix A: ControlLogix Firmware Operation Flowcharts ...direct analysis of firmware on the device. 87 Appendix A: ControlLogix Firmware Operation Flowcharts Figure A.1: Overview of ControlLogix L61 operation...105 [43] Oshana, Rob. “Introduction to JTAG”. Embedded, October 29, 2002. URL http://www.embedded.com/electronics-blogs/ beginner -s-corner/4024466
Automatic Configuration of Programmable Logic Controller Emulators
2015-03-01
25 11 Example tree generated using UPGMA [Edw13] . . . . . . . . . . . . . . . . . . . . 33 12 Example sequence alignment for two... UPGMA Unweighted Pair Group Method with Arithmetic Mean URL uniform resource locator VM virtual machine XML Extensible Markup Language xx List of...appearance in the ses- sion, and then they are clustered again using Unweighted Pair Group Method with Arithmetic Mean ( UPGMA ) with a distance matrix based
ERIC Educational Resources Information Center
Leung, Maggi W. H.; Waters, Johanna L.
2013-01-01
The fundamental logic of transnational education programmes is a one-to-one transfer of institutional capital across space and an unimportance of place. This article interrogates these presumptions and argues that space and place play an important role in transnational education. Drawing on research that examines the experiences of students and…
Control Systems of Rubber Dryer Machinery Components Using Programmable Logic Control (PLC)
NASA Astrophysics Data System (ADS)
Hendra; Yulianto, A. S.; Indriani, A.; Hernadewita; Hermiyetti
2018-02-01
Application of programmable logic control (PLC) is widely used on the control systems in the many field engineering such as automotive, aviation, food processing and other industries [1-2]. PLC is simply program to control many automatic activity, easy to use, flexible and others. PLC using the ladder program to solve and regulated the control system component. In previous research, PLC was used for control system of rotary dryer machine. In this paper PLC are used for control system of motion component in the rubber dryer machinery. Component of rubber dryer machine is motors, gearbox, sprocket, heater, drying chamber and bearing. Principle working of rubber dryer machinery is wet rubber moving into the drying chamber by sprocket. Sprocket is driven by motors that conducted by PLC to moving and set of wet rubber on the drying chamber. Drying system uses greenhouse effect by making hanger dryer design in the form of line path. In this paper focused on motion control system motors and sensors drying rubber using PLC. The results show that control system of rubber dryer machinery can work in accordance control input and the time required to dry the rubber.
McKnight, Jacob; Holt, Douglas B
2014-01-01
Expanded Programme on Immunisation (EPI) vaccination rates remain well below herd immunity in regions of many countries despite huge international resources devoted to both financing and access. We draw upon service marketing theory, organisational sociology, development anthropology and cultural consumer research to conduct an ethnographic study of vaccination delivery in Jimma Zone, Ethiopia - one such region. We find that Western public health sector policies are dominated by an administrative logic. Critical failures in delivery are produced by a system that obfuscates the on-the-ground problems that mothers face in trying to vaccinate their children, while instead prioritising administrative processes. Our ethnographic analysis of 83 mothers who had not vaccinated their children reveals key barriers to vaccination from a 'customer' perspective. While mothers value vaccination, it is a 'low involvement' good compared to the acute daily needs of a subsistence life. The costs imposed by poor service - such as uncaring staff with class hostilities, unpredictable and missed schedules and long waits - are too much and so they forego the service. Our service design framework illuminates specific service problems from the mother's perspective and points towards simple service innovations that could improve vaccination rates in regions that have poor uptake.
NASA Astrophysics Data System (ADS)
Isnur Haryudo, Subuh; Imam Agung, Achmad; Firmansyah, Rifqi
2018-04-01
The purpose of this research is to develop learning media of control technique using Matrix Laboratory software with industry requirement approach. Learning media serves as a tool for creating a better and effective teaching and learning situation because it can accelerate the learning process in order to enhance the quality of learning. Control Techniques using Matrix Laboratory software can enlarge the interest and attention of students, with real experience and can grow independent attitude. This research design refers to the use of research and development (R & D) methods that have been modified by multi-disciplinary team-based researchers. This research used Computer based learning method consisting of computer and Matrix Laboratory software which was integrated with props. Matrix Laboratory has the ability to visualize the theory and analysis of the Control System which is an integration of computing, visualization and programming which is easy to use. The result of this instructional media development is to use mathematical equations using Matrix Laboratory software on control system application with DC motor plant and PID (Proportional-Integral-Derivative). Considering that manufacturing in the field of Distributed Control systems (DCSs), Programmable Controllers (PLCs), and Microcontrollers (MCUs) use PID systems in production processes are widely used in industry.
DNA-Based Dynamic Reaction Networks.
Fu, Ting; Lyu, Yifan; Liu, Hui; Peng, Ruizi; Zhang, Xiaobing; Ye, Mao; Tan, Weihong
2018-05-21
Deriving from logical and mechanical interactions between DNA strands and complexes, DNA-based artificial reaction networks (RNs) are attractive for their high programmability, as well as cascading and fan-out ability, which are similar to the basic principles of electronic logic gates. Arising from the dream of creating novel computing mechanisms, researchers have placed high hopes on the development of DNA-based dynamic RNs and have strived to establish the basic theories and operative strategies of these networks. This review starts by looking back on the evolution of DNA dynamic RNs; in particular' the most significant applications in biochemistry occurring in recent years. Finally, we discuss the perspectives of DNA dynamic RNs and give a possible direction for the development of DNA circuits. Copyright © 2018. Published by Elsevier Ltd.
Fuzzy logic based on-line fault detection and classification in transmission line.
Adhikari, Shuma; Sinha, Nidul; Dorendrajit, Thingam
2016-01-01
This study presents fuzzy logic based online fault detection and classification of transmission line using Programmable Automation and Control technology based National Instrument Compact Reconfigurable i/o (CRIO) devices. The LabVIEW software combined with CRIO can perform real time data acquisition of transmission line. When fault occurs in the system current waveforms are distorted due to transients and their pattern changes according to the type of fault in the system. The three phase alternating current, zero sequence and positive sequence current data generated by LabVIEW through CRIO-9067 are processed directly for relaying. The result shows that proposed technique is capable of right tripping action and classification of type of fault at high speed therefore can be employed in practical application.
Chen, Lichan; Zeng, Xiaoting; Dandapat, Anirban; Chi, Yuwu; Kim, Donghwan
2015-09-01
Proteases and nucleases are enzymes heavily involved in many important biological processes, such as cancer initiation, progression, and metastasis; hence, they are indicative of potential diagnostic biomarkers. Here, we demonstrate a new label free and sensitive electrochemiluminescent (ECL) sensing strategy for protease and nuclease assays that utilize target-triggered desorption of programmable polyelectrolyte films assembled on graphite-like carbon nitride (g-C3N4) film to regulate the diffusion flux of a coreactant. Furthermore, we have built Boolean logic gates OR and AND into the polyelectrolyte films, capable of simultaneously sensing proteases and nucleases in a complicated system by breaking it into simple functions. The developed intelligent permeability controlled enzyme sensor may prove valuable in future medical diagnostics.
Issen, Laurel; Woodcock, Thomas; McNicholas, Christopher; Lennox, Laura; Reed, Julie E
2018-04-09
Despite criticisms that many quality improvement (QI) initiatives fail due to incomplete programme theory, there is no defined way to evaluate how programme theory has been articulated. The objective of this research was to develop, and assess the usability and reliability of scoring criteria to evaluate programme theory diagrams. Criteria development was informed by published literature and QI experts. Inter-rater reliability was tested between two evaluators. About 63 programme theory diagrams (42 driver diagrams and 21 action-effect diagrams) were reviewed to establish whether the criteria could support comparative analysis of different approaches to constructing diagrams. Components of the scoring criteria include: assessment of overall aim, logical overview, clarity of components, cause-effect relationships, evidence and measurement. Independent reviewers had 78% inter-rater reliability. Scoring enabled direct comparison of different approaches to developing programme theory; action-effect diagrams were found to have had a statistically significant but moderate improvement in programme theory quality over driver diagrams; no significant differences were observed based on the setting in which driver diagrams were developed. The scoring criteria summarise the necessary components of programme theory that are thought to contribute to successful QI projects. The viability of the scoring criteria for practical application was demonstrated. Future uses include assessment of individual programme theory diagrams and comparison of different approaches (e.g. methodological, teaching or other QI support) to produce programme theory. The criteria can be used as a tool to guide the production of better programme theory diagrams, and also highlights where additional support for QI teams could be needed.
Teachers' Inquiry Stance: Collaboration through Data Analysis in a Professional Learning Community
ERIC Educational Resources Information Center
Haack, Darin Marcus
2017-01-01
The purpose of this qualitative case study was to understand how teachers experience a stance toward inquiry through participation in Professional Learning Communities (PLCs). In order to meet this objective, the following questions framed this research: (1) How do individual teachers make meaning of the epistemological and dialogic aspects of…
ERIC Educational Resources Information Center
Middendorf, Beth N.
2013-01-01
Research indicated leadership played a key role in successfully implementing professional learning communities (PLCs). There has been little research on pragmatic approaches to developing PLC leaders. The purpose of this study was to examine the effectiveness of the Gene School District's two-part PLC leader development: PLC Institute and ongoing…
ERIC Educational Resources Information Center
Dalal, Shilpa D.
2013-01-01
Problem: Professional learning communities (PLCs) are not a new trend in education but are getting more attention in schools today as a vehicle for establishing collegial relationships among teachers and for building capacity for change within schools (Dufour & Eaker, 1998; Fullan, 2004; Hord, 2004; Senge, 2000). Schools are working diligently…
ERIC Educational Resources Information Center
Bozzini, Michelle D.
2017-01-01
This qualitative study explored how elementary school principals design, implement, and sustain high quality professional development through the use of professional learning communities (PLCs) in order to enhance teaching and learning. The researcher revealed the principal's important role in the design, implementation, and sustainability of a…
ERIC Educational Resources Information Center
Carpenter, Daniel
2018-01-01
Purpose: The purpose of this paper is to explore shared workspace and professional learning community (PLC) interactions in schools. The collaborative culture and PLCs were parts of the school culture. The collaborative culture of each school was designed to ensure teachers share intellectual and physical contributions in learning to investigate…
Unpacking the Roles of the Facilitator in Higher Education Professional Learning Communities
ERIC Educational Resources Information Center
Margalef, Leonor; Pareja Roblin, Natalie
2016-01-01
Facilitators are central for the success of professional learning communities (PLCs). Yet, their specific roles in supporting teacher learning remain still largely underexplored. To address this gap, the current multiple case study examines the roles of 4 university PLC facilitators, the strategies they used to support teacher learning, and the…
A Research Agenda for Professional Learning Communities: Moving Forward
ERIC Educational Resources Information Center
Hairon, Salleh; Goh, Jonathan Wee Pin; Chua, Catherine Siew Kheng; Wang, Li-yi
2017-01-01
Professional learning communities (PLCs) as a means of raising the teaching profession are becoming more attractive in education systems seeking to improve school improvement processes and outcomes. The main intention is to increase the individual and collective capacity of teachers so as to support school-wide capacity for teaching and learning.…
Collaborative Inquiry and the Shared Workspace of Professional Learning Communities
ERIC Educational Resources Information Center
Carpenter, Daniel
2017-01-01
Purpose: The purpose of this paper is to explore educator collaborative inquiry in the shared workspace in professional learning communities (PLCs). Specifically, this investigation was part of an ongoing investigation of well-established PLC collaborative interactions and self-directed learning of educators as part of the shared workspace as a…
Facilitation for Professional Learning Community Conversations in Singapore
ERIC Educational Resources Information Center
Salleh, Hairon
2016-01-01
Professional Learning Community (PLC) has steadily grown in importance over the last decade. The growing importance of PLCs lies in its potential to act as a lever for school-based curriculum development and innovation so as to provide diverse learning experiences to satisfy broader learning outcomes beyond academic achievements (e.g., the…
ERIC Educational Resources Information Center
Owen, Susanne Mary
2015-01-01
Innovative educational approaches for schooling require changes to the traditional teacher role towards operating as co-facilitators and co-learners, and working in teacher teams, with considerable professional learning supporting this. Professional learning communities (PLCs) have been acknowledged as highly effective, with their characteristics…
ERIC Educational Resources Information Center
Shaner, Robert G.
2009-01-01
Professional learning communities (PLC) have been identified as scaffolds that can facilitate, support, and sustain systemic change focused on improving student achievement. PLCs represent the application of the theoretical constructs of the learning organization within the framework of schools and school systems. Little is known about the change…
A Program Evaluation of the Effects of PLCs on Direct Interactive Instruction
ERIC Educational Resources Information Center
Reyes, Deirdre
2014-01-01
Increased student achievement is the goal of all educators, and to that end, teachers must engage in professional development so that they are introduced to new strategies. Moreover, these professional development offerings must be sustained with a follow-up plan that allows teachers to practice strategies and reflect and collaborate with…
Enhancing Self-Efficacy in Elementary Science Teaching with Professional Learning Communities
ERIC Educational Resources Information Center
Mintzes, Joel J.; Marcum, Bev; Messerschmidt-Yates, Christl; Mark, Andrew
2013-01-01
Emerging from Bandura's Social Learning Theory, this study of in-service elementary school teachers examined the effects of sustained Professional Learning Communities (PLCs) on self-efficacy in science teaching. Based on mixed research methods, and a non-equivalent control group experimental design, the investigation explored changes in…
ERIC Educational Resources Information Center
Bedford, Laurie A.; Rossow, Katie A.
2017-01-01
Virtual Professional Learning Communities (PLC) have become an innovative way to meet the professional development needs of faculty in the online learning environment. Walden University's model for PLCs, the Walden Junto, uses a combination of synchronous and asynchronous online strategies and is based on a philosophy that embraces the faculty…
ERIC Educational Resources Information Center
Jones, Christopher M.
2013-01-01
In the 21st century, increased school accountability has sharpened the focus of school and district leaders on improving instructional practice to raise student achievement. The implementation of professional leaning communities (PLCs) is one improvement effort in which schools establish collaborative cultures focused on increasing student…
ERIC Educational Resources Information Center
Mathews, Tracy A.
2017-01-01
This quantitative correlation survey study investigated the relationship between teachers' perceptions of the effectiveness of school principals as instructional leaders in professional learning communities (PLCs) and self-efficacy beliefs of teachers. Social Cognitive Theory, self-efficacy concept, and Adult Learning Theory were at the core of…
ERIC Educational Resources Information Center
Garcia, Maria M.
2013-01-01
This study focused on describing teachers' perspectives in reference to cooperative learning, students diagnosed with ADHD, and teacher participation in professional learning communities (PLCs). A quantitative methodology, survey study method was used to collect information. The literature review on ADHD and Cooperative Learning helped…
Distributed Leadership to Support PLCs in Asian Pragmatic Singapore Schools
ERIC Educational Resources Information Center
Hairon, Salleh; Goh, Jonathan Wee Pin; Lin, Tzu-Bin
2014-01-01
Nation states around the world, including Singapore, are endeavouring to reform their education systems in order to successfully compete in the global economy (Carnoy, 1999). With human capital as Singapore's primary resource, it is unsurprising that the state has placed great emphasis on strengthening the economic-education nexus. This tight…
ERIC Educational Resources Information Center
Branch, Mary Grace
2011-01-01
This study explores the coaching experiences of educational administrators in an attempt to gain greater understanding of how they develop the necessary skills to implement, lead, and support technology rich professional learning communities (PLCs). Participants came from a mix of urban, rural, and suburban school districts. Using semi-structured…
ERIC Educational Resources Information Center
Hallam, Pamela R.; Smith, Henry R.; Hite, Julie M.; Hite, Steven J.; Wilcox, Bradley R.
2015-01-01
Professional learning communities (PLCs) are being recognized as effective in improving teacher collaboration and student achievement. Trust is critical in effectively implementing the PLC model, and the school principal is best positioned to influence school trust levels. Using five facets of trust, this research sought to clarify the impact of…
Just the Facts: Personal Learning Networks
ERIC Educational Resources Information Center
Nussbaum-Beach, Sheryl
2013-01-01
One has heard about personal learning networks (PLNs), but what are they and how are they different than professional learning communities (PLCs)? Find out how PLNs can help a teacher pursue his/her own professional interests and be a better teacher. This article answers questions related to PLNs such as: (1) What are personal learning networks?;…
Cheng, Jiongjia; Goldstein, Rebecca; Stec, Boguslaw; Gershenson, Anne; Roberts, Mary F.
2012-01-01
Staphylococcus aureus phosphatidylinositol-specific phospholipase C (PI-PLC) is a secreted virulence factor for this pathogenic bacterium. A novel crystal structure shows that this PI-PLC can form a dimer via helix B, a structural feature present in all secreted, bacterial PI-PLCs that is important for membrane binding. Despite the small size of this interface, it is critical for optimal enzyme activity. Kinetic evidence, increased enzyme specific activity with increasing enzyme concentration, supports a mechanism where the PI-PLC dimerization is enhanced in membranes containing phosphatidylcholine (PC). Mutagenesis of key residues confirm that the zwitterionic phospholipid acts not by specific binding to the protein, but rather by reducing anionic lipid interactions with a cationic pocket on the surface of the S. aureus enzyme that stabilizes monomeric protein. Despite its structural and sequence similarity to PI-PLCs from other Gram-positive pathogenic bacteria, S. aureus PI-PLC appears to have a unique mechanism where enzyme activity is modulated by competition between binding of soluble anions or anionic lipids to the cationic sensor and transient dimerization on the membrane. PMID:23038258
NASA Astrophysics Data System (ADS)
Wang, Yonggang; Kuang, Jie; Liu, Chong; Cao, Qiang; Li, Deng
2017-03-01
A high performance multi-channel time-to-digital converter (TDC) is implemented in a Xilinx Zynq-7000 field programmable gate array (FPGA). It can be flexibly configured as either 32 TDC channels with 9.9 ps time-interval RMS precision, 16 TDC channels with 6.9 ps RMS precision, or 8 TDC channels with 5.8 ps RMS precision. All TDCs have a 380 M Samples/second measurement throughput and a 2.63 ns measurement dead time. The performance consistency and temperature dependence of TDC channels are also evaluated. Because Zynq-7000 FPGA family integrates a feature-rich dual-core ARM based processing system and 28 nm Xilinx programmable logic in a single device, the realization of high performance TDCs on it will make the platform more widely used in time-measuring related applications.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
The final report for the project is presented in five volumes. This volume is the Programmer's Manual. It covers: a system overview, attractiveness component of gravity model, trip-distribution component of gravity model, economic-effects model, and the consumer-surplus model. The project sought to determine the impact of Outer Continental Shelf development on recreation and tourism.
Firmware Modification Analysis in Programmable Logic Controllers
2014-03-27
security and operational requirements [18, 19]. Money is a factor for the DOD but not a driving one. With private industry, money is a primary influential... functions in the original firmware. A proof-of-concept experiment demonstrates the functionality of the analysis tool using different firmware versions...Opcode Difference Comparison . . . . . . . . . . . . . . 37 3.1.2.3 Function Difference Comparison . . . . . . . . . . . . . 37 3.1.2.4 Call Graph
Danger of Prolific Cybercrime and Network DDOS from Unprotected IoT Devices
been around for more than 40 years. But people didn't know about it because most of the internet of things was industrial internet of things. So when you had programmable logical controls, remote terminal for People Power Company. And Scott Wu is also from NewSky. He's on as well. And we'll talk a few
1998-04-01
selected is statistically based on the total number of faults and the failure rate distribution in the system under test. The fault set is also...implemented the BPM and system level emulation consolidation logic as well as statistics counters for cache misses and various bus transactions. These...instruction F22 Advanced Tactical Fighter FET Field Effect Transitor FF Flip-Flop FM Failures/Milhon hours C-3 FPGA Field Programmable Gate Array GET
Unappreciated epidemiology: the churn effect in a regional HIV care programme.
Gill, M J; Krentz, H B
2009-08-01
High levels of geographic mobility in and out of HIV care centres (i.e. the churn effect) can disrupt the continuity of patient care, misalign prevention services, impact local prevalence data perturbing optimal allocation of resources, and contribute to logical challenges in repeated transfer of health records. We report on the clinical, demographic, and administrative impact of high population turnover within HIV populations.
Standard Transistor Array (Star): SIMLOG/TESTGN programmer's guide, volume 2, addendum 2
NASA Technical Reports Server (NTRS)
Carroll, B. D.
1979-01-01
A brief introduction to the SIMLOG/TESTGN system of programs is given. SIMLOG is a logic simulation program, whereas TESTGN is a program for generating test sequences from output produced by SIMLOG. The structures of the two programs are described. Data base, main program, and subprogram details are also given. Guidelines for program modifications are discussed. Commented program listings are included.
Sensor sentinel computing device
Damico, Joseph P.
2016-08-02
Technologies pertaining to authenticating data output by sensors in an industrial environment are described herein. A sensor sentinel computing device receives time-series data from a sensor by way of a wireline connection. The sensor sentinel computing device generates a validation signal that is a function of the time-series signal. The sensor sentinel computing device then transmits the validation signal to a programmable logic controller in the industrial environment.
NASA Astrophysics Data System (ADS)
Greuter, U.; Buehler, C.; Rasmussen, P.; Emmenegger, M.; Maden, D.; Koennecke, M.; Schlumpf, N.
We present the basic concept and the realization of our fully configurable data-acquisition hardware for the neutron scattering instruments at SINQ. This system allows collection of the different data entities and event-related signals generated by the various detector units. It offers a variety of synchronization options, including a time-measuring mode for time-of-flight determinations. Based on configurable logic (FPGA, CPLD), event rates up to the MHz range can be processed and transmitted to a programmable online data-reduction system (Histogram Memory). It is implemented on a commercially available VME Power PC module running a real-time operating system (VxWorks).
A partnership model of early intervention in psychosis programme--a Canadian experience.
Oyewumi, Lamidi Kola; Savage, Troy
2009-08-01
To describe how a new partnership model of early intervention in psychosis, early intervention in psychosis (EIP) programme delivery in Canada attracted the interest of the community and acquired government funding. The process by which a few individuals used a conceptual framework of integrated, collaborative, flexible and recovery focused principles to engage community partners and attract government funding is described. The establishment of a small EIP programme and its expansion to a regional programme serving an area of 20,000 square kilometers and a population of approximately 500,000 people were achieved. A programme specific logic prototype was developed. A synergy of public, private and academic services emerged with an infrastructure for ongoing cohesiveness and productivity. Annual clinic visits increased from 641 in 2002 to 1904 in 2007 and annual new patients enrollments grew from 46 to 128 within the same period. Staffing grew from an interdisciplinary staff of 1.5 full-time equivalent (FTE) to the current 10.0 FTE. A carefully orchestrated programme organization that is inclusive rather than exclusive can produce a balance of evidence-based best practices in client focused service, community mental health integration and academic productivity. © 2009 The Authors. Journal compilation © 2009 Blackwell Publishing Asia Pty Ltd.
PROGRAPE-1: A Programmable, Multi-Purpose Computer for Many-Body Simulations
NASA Astrophysics Data System (ADS)
Hamada, Tsuyoshi; Fukushige, Toshiyuki; Kawai, Atsushi; Makino, Junichiro
2000-10-01
We have developed PROGRAPE-1 (PROgrammable GRAPE-1), a programmable multi-purpose computer for many-body simulations. The main difference between PROGRAPE-1 and ``traditional'' GRAPE systems is that the former uses FPGA (Field Programmable Gate Array) chips as the processing elements, while the latter relies on a hardwired pipeline processor specialized to gravitational interactions. Since the logic implemented in FPGA chips can be reconfigured, we can use PROGRAPE-1 to calculate not only gravitational interactions, but also other forms of interactions, such as the van der Waals force, hydro\\-dynamical interactions in the SPHr calculation, and so on. PROGRAPE-1 comprises two Altera EPF10K100 FPGA chips, each of which contains nominally 100000 gates. To evaluate the programmability and performance of PROGRAPE-1, we implemented a pipeline for gravitational interactions similar to that of GRAPE-3. One pipeline is fitted into a single FPGA chip, operated at 16 MHz clock. Thus, for gravitational interactions, PROGRAPE-1 provided a speed of 0.96 Gflops-equivalent. PROGRAPE will prove to be useful for a wide-range of particle-based simulations in which the calculation cost of interactions other than gravity is high, such as the evaluation of SPH interactions.
Scourfield, J; Nasiruddin, Q
2015-09-01
Amid concern about the reach and inclusivity of parenting interventions, attempts have been made to culturally adapt programmes for specific ethnic or linguistic groups. This paper describes a novel approach of the religious adaptation of a parenting programme, namely the Family Links Islamic Values course. A small-scale qualitative process evaluation was conducted on one Family Links Islamic Values course for Muslim fathers in the South of England in order to describe the intervention as implemented and its theory of change, as well as the acceptability of the programme to the participants. The data consisted of 13 semi-structured interviews (10 with parents and three with staff), 25 h of observation and reading of programme manuals. A logic model is presented to describe the theoretical basis of the intervention. The programme was highly acceptable to fathers who valued the integration of religious teachings and were generally very positive about their experience of attending the course. Post-course interviews with both fathers and mothers mentioned some positive changes in fathers as a result of their attendance. It is important to be responsive to the needs of some British Muslims for religiously credible interventions. This small-scale process evaluation needs to be followed by a robust evaluation of programme outcomes for parents and children. © 2015 The Authors. Child: Care, Health and Development published by John Wiley & Sons Ltd.
Nasiruddin, Q.
2015-01-01
Abstract Background Amid concern about the reach and inclusivity of parenting interventions, attempts have been made to culturally adapt programmes for specific ethnic or linguistic groups. This paper describes a novel approach of the religious adaptation of a parenting programme, namely the Family Links Islamic Values course. Methods A small‐scale qualitative process evaluation was conducted on one Family Links Islamic Values course for Muslim fathers in the South of England in order to describe the intervention as implemented and its theory of change, as well as the acceptability of the programme to the participants. The data consisted of 13 semi‐structured interviews (10 with parents and three with staff), 25 h of observation and reading of programme manuals. Results A logic model is presented to describe the theoretical basis of the intervention. The programme was highly acceptable to fathers who valued the integration of religious teachings and were generally very positive about their experience of attending the course. Post‐course interviews with both fathers and mothers mentioned some positive changes in fathers as a result of their attendance. Conclusions It is important to be responsive to the needs of some British Muslims for religiously credible interventions. This small‐scale process evaluation needs to be followed by a robust evaluation of programme outcomes for parents and children. PMID:25649634
Is It Personal? Teacher's Personality and the Principal's Role in Professional Learning Communities
ERIC Educational Resources Information Center
Benoliel, Pascale; Schechter, Chen
2017-01-01
Research results have provided evidence of the potential contribution that professional learning communities (PLCs) can make to enhance school outcomes. While numerous organizational and cultural aspects of schools have been recognized as key requirements for PLC success, researchers have noted that a teacher's ability to share knowledge in the…
ERIC Educational Resources Information Center
De Neve, Debbie; Devos, Geert
2017-01-01
Research has shown that adequate support from the school environment is necessary to help beginning teachers in applying differentiated instruction (DI), but how schools can aid in this process remains unclear. This qualitative study explores how professional learning communities (PLCs), an indicator of a supportive school environment, can enhance…
Getting the Right Fit: Designing a Professional Learning Community for Out-of-School Time
ERIC Educational Resources Information Center
Vance, Femi; Salvaterra, Emily; Michelsen, Jocelyn Atkins; Newhouse, Corey
2016-01-01
A skilled workforce is critical in high-quality out-of-school time (OST) programs. However, the workshops commonly used to train OST staff are not adequately preparing practitioners to deliver quality programs that can benefit youth. Professional learning communities (PLCs) are a practice-focused alternative that has a track record of improving…
ERIC Educational Resources Information Center
Kuehl, Rachelle
2018-01-01
The purpose of this study was to explore the use of Professional Learning Communities (PLCs) in preservice teacher education as a tool for learning about differentiation within writing instruction. Using online dialogue journals, preservice teachers communicated with elementary students about a shared text and met in ongoing PLC groups to examine…
Transferring Information from Faculty Development to Classroom Practice: A Mixed-Method Study
ERIC Educational Resources Information Center
Winslow, Matthew P.; Skubik-Peplaski, Camille; Burkett, Barry
2017-01-01
Professional learning communities (PLCs) are an effective way for faculty to learn about pedagogical topics and tactics. However, less is known about how effective they are at changing the teaching practices of the faculty participants and ultimately student learning. This article describes a mixed-method study of such a transfer of knowledge. In…
ERIC Educational Resources Information Center
Hardman, Elizabeth L.
2011-01-01
This paper examines the challenges inherent in building professional learning communities (PLCs) in special education and describes how two Web 2.0 tools were used to build a community that engages general and special education teachers, school administrators, and teacher educators in implementing research based inclusive practices that are known…
ERIC Educational Resources Information Center
Brucker, Elizabeth L.
2013-01-01
The purpose of this study was to investigate teachers' perceptions of levels of implementation and levels of effectiveness in improving student learning of Professional Learning Communities (PLCs) in Kanawha County Schools. This study also sought to determine differences in levels of implementation and effectiveness for five selected independent…
ERIC Educational Resources Information Center
Wise, Kristi
2017-01-01
Professional Learning Communities (PLCs) are a best practice that has been around for decades; however, due to organizational structuring in elementary schools, teachers are allowed 30 minutes of planning time. During this time little planning or collaboration with peers is achieved. Previous research has proven that professional learning by way…
ERIC Educational Resources Information Center
Woodland, Rebecca H.; Mazur, Rebecca
2015-01-01
Educational evaluation (Ed Eval) and professional learning communities (PLCs) are two of the nation's most predominant approaches to widespread instructional improvement. Yet key attributes of these reform initiatives are too often experienced by teachers as burdensome, or even detrimental, rather than helpful. The authors of this article contend…
Experiences of Elementary Music Teachers in a Subject-Specific Professional Learning Community
ERIC Educational Resources Information Center
Anderson, Amy K.
2013-01-01
The purpose of this qualitative case study was to identify ways in which teachers' participation in a subject-specific music professional learning community (PLC) impacts instruction and assessment of musical skills. Previous studies have provided evidence of PLCs' impact on teaching and student learning in many subject areas, but little has been…
ERIC Educational Resources Information Center
Blitz, Cynthia L.
2013-01-01
For more than a decade practitioners have promoted professional learning communities (PLCs) as an effective structure for providing teachers with professional development (Chappuis, Chappuis, & Stiggins, 2009; DuFour, Eaker, & DuFour, 2005). These collaborative networks are believed to be effective because they expose teachers to new ideas…
ERIC Educational Resources Information Center
Marx, Megan D.
2016-01-01
The purpose of this study was to determine variance in mean levels of teacher self-efficacy (TSE) and its three factors--efficacy in student engagement (EIS), efficacy in instructional strategies (EIS), and efficacy in classroom management (ECM)--based on participation and time spent in professional learning communities (PLCs). In this…
ERIC Educational Resources Information Center
Dogan, Selcuk; Pringle, Rose; Mesa, Jennifer
2016-01-01
The purpose of this article is to provide a review of empirical studies investigating the impact of professional learning communities (PLCs) on science teachers' practices and knowledge. Across 14 articles that satisfied the definition we embraced, most were devoted to the change in science teaching practices, disciplinary content knowledge (DCK)…
ERIC Educational Resources Information Center
Lee, Stephanie A.
2016-01-01
Increasing standardized test scores and identifying factors that impact student performance are always on the minds of educators. Educators are continually challenged by experts to consider professional learning communities (PLCs) as a viable pathway to school reform. This treatise will report on the results of a quantitative research study…
ERIC Educational Resources Information Center
Allen, Claudette M.
2017-01-01
Empirical research has suggested that professional learning communities (PLCs) and employee engagement have a positive impact on the school community, school culture, and academic achievement. Further research has postulated that school leadership is one of the most important ingredients in the success of schools. But do school leaders have any…
ERIC Educational Resources Information Center
Padilla, Jennifer Lynn
2013-01-01
Professional learning communities (PLCs) have gained attention as an effective practice for supporting teachers and developing students since their inception in the early 1990s yet there is still work to be done in developing a blueprint for effective implementation in a pervasive culture of isolation and resistance, especially in secondary…
ERIC Educational Resources Information Center
Harak, Philip J.
2012-01-01
Although public school teaching by its inherent nature presents numerous classroom challenges, the public high school teacher today is faced in addition with multiple external mandates from several outside stakeholders. Given the established track record of professional learning communities (PLCs) to provide teacher support and development, I…
PLCs in Action: Innovative Teaching for Struggling Grade 3-5 Readers
ERIC Educational Resources Information Center
D'Ardenne, Charna; Barnes, Debra G.; Hightower, Elaine S.; Lamason, Pamela R.; Mason, Mary; Patterson, Paula C.; Stephens, Nancy; Wilson, Carolyn E.; Smith, Vickie H.; Erickson, Karen A.
2013-01-01
A group of elementary school reading teachers used their time in a Professional Learning Community to develop a systematic intervention to address the needs of struggling readers in grades 3 to 5. Working as a team, they identified a collection of books that was culturally diverse, high interest, appealing to boys and girls, aligned with…
ERIC Educational Resources Information Center
Gray, Julie; Kruse, Sharon; Tarter, C. John
2016-01-01
This study tested the role of enabling school structures, collegial trust and academic emphasis in the development of professional learning communities (PLCs) in a low-income school district. The empirical study was based upon the perceptions of teachers and principals as provided by survey responses (N = 67 schools). While enabling school…
Bistable metamaterial for switching and cascading elastic vibrations
Foehr, André; Daraio, Chiara
2017-01-01
The realization of acoustic devices analogous to electronic systems, like diodes, transistors, and logic elements, suggests the potential use of elastic vibrations (i.e., phonons) in information processing, for example, in advanced computational systems, smart actuators, and programmable materials. Previous experimental realizations of acoustic diodes and mechanical switches have used nonlinearities to break transmission symmetry. However, existing solutions require operation at different frequencies or involve signal conversion in the electronic or optical domains. Here, we show an experimental realization of a phononic transistor-like device using geometric nonlinearities to switch and amplify elastic vibrations, via magnetic coupling, operating at a single frequency. By cascading this device in a tunable mechanical circuit board, we realize the complete set of mechanical logic elements and interconnect selected ones to execute simple calculations. PMID:28416663
Synthesis of energy-efficient FSMs implemented in PLD circuits
NASA Astrophysics Data System (ADS)
Nawrot, Radosław; Kulisz, Józef; Kania, Dariusz
2017-11-01
The paper presents an outline of a simple synthesis method of energy-efficient FSMs. The idea consists in using local clock gating to selectively block the clock signal, if no transition of a state of a memory element is required. The research was dedicated to logic circuits using Programmable Logic Devices as the implementation platform, but the conclusions can be applied to any synchronous circuit. The experimental section reports a comparison of three methods of implementing sequential circuits in PLDs with respect to clock distribution: the classical fully synchronous structure, the structure exploiting the Enable Clock inputs of memory elements, and the structure using clock gating. The results show that the approach based on clock gating is the most efficient one, and it leads to significant reduction of dynamic power consumed by the FSM.
B-Plant Canyon Ventilation Control System Description
DOE Office of Scientific and Technical Information (OSTI.GOV)
MCDANIEL, K.S.
1999-08-31
Project W-059 installed a new B Plant Canyon Ventilation System. Monitoring and control of the system is implemented by the Canyon Ventilation Control System (CVCS). This document describes the CVCS system components which include a Programmable Logic Controller (PLC) coupled with an Operator Interface Unit (OIU) and application software. This document also includes an Alarm Index specifying the setpoints and technical basis for system analog and digital alarms.
Electrokinetic Microactuator Arrays for Control of Vehicles
2002-08-01
programmable logic array (PLA) content in each unit cell....................46 Chapter 4 4.1 Schematic showing electroosmotic flow induced by an...control situations involved in propulsion systems, spanning from con- trol of mixing in advanced gas turbine combustors, to active control of surge and... electroosmotic flow, shown schematically in Fig. 4.1, results when an electric field is applied to a liquid electrolyte in contact with a charged solid
Evolvable Hardware for Space Applications
NASA Technical Reports Server (NTRS)
Lohn, Jason; Globus, Al; Hornby, Gregory; Larchev, Gregory; Kraus, William
2004-01-01
This article surveys the research of the Evolvable Systems Group at NASA Ames Research Center. Over the past few years, our group has developed the ability to use evolutionary algorithms in a variety of NASA applications ranging from spacecraft antenna design, fault tolerance for programmable logic chips, atomic force field parameter fitting, analog circuit design, and earth observing satellite scheduling. In some of these applications, evolutionary algorithms match or improve on human performance.
A reconfigurable cryogenic platform for the classical control of quantum processors
NASA Astrophysics Data System (ADS)
Homulle, Harald; Visser, Stefan; Patra, Bishnu; Ferrari, Giorgio; Prati, Enrico; Sebastiano, Fabio; Charbon, Edoardo
2017-04-01
The implementation of a classical control infrastructure for large-scale quantum computers is challenging due to the need for integration and processing time, which is constrained by coherence time. We propose a cryogenic reconfigurable platform as the heart of the control infrastructure implementing the digital error-correction control loop. The platform is implemented on a field-programmable gate array (FPGA) that supports the functionality required by several qubit technologies and that can operate close to the physical qubits over a temperature range from 4 K to 300 K. This work focuses on the extensive characterization of the electronic platform over this temperature range. All major FPGA building blocks (such as look-up tables (LUTs), carry chains (CARRY4), mixed-mode clock manager (MMCM), phase-locked loop (PLL), block random access memory, and IDELAY2 (programmable delay element)) operate correctly and the logic speed is very stable. The logic speed of LUTs and CARRY4 changes less then 5%, whereas the jitter of MMCM and PLL clock managers is reduced by 20%. The stability is finally demonstrated by operating an integrated 1.2 GSa/s analog-to-digital converter (ADC) with a relatively stable performance over temperature. The ADCs effective number of bits drops from 6 to 4.5 bits when operating at 15 K.
A reconfigurable cryogenic platform for the classical control of quantum processors.
Homulle, Harald; Visser, Stefan; Patra, Bishnu; Ferrari, Giorgio; Prati, Enrico; Sebastiano, Fabio; Charbon, Edoardo
2017-04-01
The implementation of a classical control infrastructure for large-scale quantum computers is challenging due to the need for integration and processing time, which is constrained by coherence time. We propose a cryogenic reconfigurable platform as the heart of the control infrastructure implementing the digital error-correction control loop. The platform is implemented on a field-programmable gate array (FPGA) that supports the functionality required by several qubit technologies and that can operate close to the physical qubits over a temperature range from 4 K to 300 K. This work focuses on the extensive characterization of the electronic platform over this temperature range. All major FPGA building blocks (such as look-up tables (LUTs), carry chains (CARRY4), mixed-mode clock manager (MMCM), phase-locked loop (PLL), block random access memory, and IDELAY2 (programmable delay element)) operate correctly and the logic speed is very stable. The logic speed of LUTs and CARRY4 changes less then 5%, whereas the jitter of MMCM and PLL clock managers is reduced by 20%. The stability is finally demonstrated by operating an integrated 1.2 GSa/s analog-to-digital converter (ADC) with a relatively stable performance over temperature. The ADCs effective number of bits drops from 6 to 4.5 bits when operating at 15 K.
ELIPS: Toward a Sensor Fusion Processor on a Chip
NASA Technical Reports Server (NTRS)
Daud, Taher; Stoica, Adrian; Tyson, Thomas; Li, Wei-te; Fabunmi, James
1998-01-01
The paper presents the concept and initial tests from the hardware implementation of a low-power, high-speed reconfigurable sensor fusion processor. The Extended Logic Intelligent Processing System (ELIPS) processor is developed to seamlessly combine rule-based systems, fuzzy logic, and neural networks to achieve parallel fusion of sensor in compact low power VLSI. The first demonstration of the ELIPS concept targets interceptor functionality; other applications, mainly in robotics and autonomous systems are considered for the future. The main assumption behind ELIPS is that fuzzy, rule-based and neural forms of computation can serve as the main primitives of an "intelligent" processor. Thus, in the same way classic processors are designed to optimize the hardware implementation of a set of fundamental operations, ELIPS is developed as an efficient implementation of computational intelligence primitives, and relies on a set of fuzzy set, fuzzy inference and neural modules, built in programmable analog hardware. The hardware programmability allows the processor to reconfigure into different machines, taking the most efficient hardware implementation during each phase of information processing. Following software demonstrations on several interceptor data, three important ELIPS building blocks (a fuzzy set preprocessor, a rule-based fuzzy system and a neural network) have been fabricated in analog VLSI hardware and demonstrated microsecond-processing times.
A binary link tracker for the BaBar level 1 trigger system
DOE Office of Scientific and Technical Information (OSTI.GOV)
Berenyi, A.; Chen, H.K.; Dao, K.
1999-08-01
The BaBar detector at PEP-II will operate in a high-luminosity e{sup +}e{sup {minus}} collider environment near the {Upsilon}(4S) resonance with the primary goal of studying CP violation in the B meson system. In this environment, typical physics events of interest involve multiple charged particles. These events are identified by counting these tracks in a fast first level (Level 1) trigger system, by reconstructing the tracks in real time. For this purpose, a Binary Link Tracker Module (BLTM) was designed and fabricated for the BaBar Level 1 Drift Chamber trigger system. The BLTM is responsible for linking track segments, constructed bymore » the Track Segment Finder Modules (TSFM), into complete tracks. A single BLTM module processes a 360 MBytes/s stream of segment hit data, corresponding to information from the entire Drift Chamber, and implements a fast and robust algorithm that tolerates high hit occupancies as well as local inefficiencies of the Drift Chamber. The algorithms and the necessary control logic of the BLTM were implemented in Field Programmable Gate Arrays (FPGAs), using the VHDL hardware description language. The finished 9U x 400 mm Euro-format board contains roughly 75,000 gates of programmable logic or about 10,000 lines of VHDL code synthesized into five FPGAs.« less
Programmable in vivo selection of arbitrary DNA sequences.
Ben Yehezkel, Tuval; Biezuner, Tamir; Linshiz, Gregory; Mazor, Yair; Shapiro, Ehud
2012-01-01
The extraordinary fidelity, sensory and regulatory capacity of natural intracellular machinery is generally confined to their endogenous environment. Nevertheless, synthetic bio-molecular components have been engineered to interface with the cellular transcription, splicing and translation machinery in vivo by embedding functional features such as promoters, introns and ribosome binding sites, respectively, into their design. Tapping and directing the power of intracellular molecular processing towards synthetic bio-molecular inputs is potentially a powerful approach, albeit limited by our ability to streamline the interface of synthetic components with the intracellular machinery in vivo. Here we show how a library of synthetic DNA devices, each bearing an input DNA sequence and a logical selection module, can be designed to direct its own probing and processing by interfacing with the bacterial DNA mismatch repair (MMR) system in vivo and selecting for the most abundant variant, regardless of its function. The device provides proof of concept for programmable, function-independent DNA selection in vivo and provides a unique example of a logical-functional interface of an engineered synthetic component with a complex endogenous cellular system. Further research into the design, construction and operation of synthetic devices in vivo may lead to other functional devices that interface with other complex cellular processes for both research and applied purposes.
Automated Translation of Safety Critical Application Software Specifications into PLC Ladder Logic
NASA Technical Reports Server (NTRS)
Leucht, Kurt W.; Semmel, Glenn S.
2008-01-01
The numerous benefits of automatic application code generation are widely accepted within the software engineering community. A few of these benefits include raising the abstraction level of application programming, shorter product development time, lower maintenance costs, and increased code quality and consistency. Surprisingly, code generation concepts have not yet found wide acceptance and use in the field of programmable logic controller (PLC) software development. Software engineers at the NASA Kennedy Space Center (KSC) recognized the need for PLC code generation while developing their new ground checkout and launch processing system. They developed a process and a prototype software tool that automatically translates a high-level representation or specification of safety critical application software into ladder logic that executes on a PLC. This process and tool are expected to increase the reliability of the PLC code over that which is written manually, and may even lower life-cycle costs and shorten the development schedule of the new control system at KSC. This paper examines the problem domain and discusses the process and software tool that were prototyped by the KSC software engineers.
High-performance reconfigurable coincidence counting unit based on a field programmable gate array.
Park, Byung Kwon; Kim, Yong-Su; Kwon, Osung; Han, Sang-Wook; Moon, Sung
2015-05-20
We present a high-performance reconfigurable coincidence counting unit (CCU) using a low-end field programmable gate array (FPGA) and peripheral circuits. Because of the flexibility guaranteed by the FPGA program, we can easily change system parameters, such as internal input delays, coincidence configurations, and the coincidence time window. In spite of a low-cost implementation, the proposed CCU architecture outperforms previous ones in many aspects: it has 8 logic inputs and 4 coincidence outputs that can measure up to eight-fold coincidences. The minimum coincidence time window and the maximum input frequency are 0.47 ns and 163 MHz, respectively. The CCU will be useful in various experimental research areas, including the field of quantum optics and quantum information.
ERIC Educational Resources Information Center
Rodriguez, Gabriel R.
2017-01-01
A growing number of schools are implementing PLCs to address school improvement, staff engage with data to identify student needs and determine instructional interventions. This is a starting point for engaging in the iterative process of learning for the teach in order to increase student learning (Hord & Sommers, 2008). The iterative process…
ERIC Educational Resources Information Center
Hands, Catherine; Guzar, Katlyn; Rodrigue, Anne
2015-01-01
A professional learning community (PLC) is one of the most promising strategies for effecting change in educational practices to improve academic achievement and wellbeing for all students. The PLC facilitator's role in developing and leading blended (online and face-to-face) PLCs with members from Ontario's school districts was examined through a…
ERIC Educational Resources Information Center
Askew, Cheryl Cessna
2012-01-01
This research explored the perceptions of high school principals and teachers on the implementation of professional learning communities (PLCs) in their schools. These perceptions were surveyed using the Professional Learning Communities Assessment-Revised (PLCA-R). Data results were examined for areas of agreement and disagreement between the…
ERIC Educational Resources Information Center
Patrick, Susan McClendon
2013-01-01
The purpose of this study was to conduct a meta-analysis of dissertation research that examined the implementation of professional learning communities (PLCs) and student achievement in preK-12 schools. An exhaustive search for such unpublished studies was conducted using the following criteria: 1) the studies were available on dissertation…