Organic low voltage rewritable memory device based on PEDOT:PSS/f-MWCNTs thin film

We report on devices constructed using a small quantity (?0.01 wt.%) of functionalized multiwalled carbon nanotubes (f-MWCNTs) embedded in a conducting polymer (poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate), PEDOT:PSS) matrix and aluminum top electrodes, prepared on indium-tin-oxide (ITO) substrates. Our ITO/(PEDOT:PSS + f-MWCNTs)/Al devices show current bistability. The low resistance ON-state, as well as the high resistance OFF state, retain the information for hours and are stable after hundreds of write–read–erase–read (WRER) cycles, being potentially interesting for erasable and rewritable volatile memory device applications. Moreover, the operation voltages used for performing these WRER cycles are very low. The threshold voltage for OFF to ON switching can be adjusted changing the f-MWCNTs concentration. Our results suggest that the nanotubes are necessary for the production of an inhomogeneous electric field playing a role in the electroforming (dielectric breakdown) of the aluminum oxide layer at the Al₂O₃/(PEDOT:PSS) interface.     

Flexible rewritable organic memory devices using nitrogen-doped CNTs/PEDOT:PSS composites

Nonvolatile rewritable organic memory devices based on poly(3,4-ethylene dioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) and nitrogen doped multi-walled carbon nanotube (NCNT) nanocomposites were fabricated on glass and PET substrates.Organic memory devices with bistable resistive switching were obtained using very low NCTN concentration (∼0.002 wt%) in the polymeric matrix. The memory devices exhibited a good ON/OFF ratio of approximately three orders of magnitude, a good retention time of 10⁴ s under operating voltages ≤ |4V| and a few hundredths of write-read-erase-read cycles. The bistable resistive switching is mainly attributed to the creation of oxygen vacancies. These defects are introduced into the thin native Al oxide (AlOx) layer on the bottom electrode during the first voltage sweep. The well-dispersed NCNTs immersed in PEDOT:PSS play a key role as conductive channels for the electronic transport, hindering the electron trapping at the AlOx-polymer interface and inducing a soft dielectric breakdown of the AlOx layer. These PEDOT:PSS + NCNTs memory devices are to easy to apply in flexible low-cost technology and provide the possibility of large-scale integration.     

The PAPIA system

In 1983 an Italian research program was begun for the design, simulation and construction of a multiprocessor image processing system. After a first phase devoted to the comparison of suggested and existing systems and to the definition of a set of benchmarks, a new system was defined. The structure of this new system is introduced here: it is based on a fine-grained pyramid of processors built up by means of a pyramidal cell implemented on a VLSI multiprocessor chip. The peculiarities and the capabilities of the processing element are highlighted. The complete hardware and software system has been fully designed and is described. A first working prototype has been built and is now operational.     

The PAPIA system

In 1983 an Italian research program was begun for the design, simulation and construction of a multiprocessor image processing system. After a first phase devoted to the comparison of suggested and existing systems and to the definition of a set of benchmarks, a new system was defined. The structure of this new system is introduced here: it is based on a fine-grained pyramid of processors built up by means of a pyramidal cell implemented on a VLSI multiprocessor chip. The peculiarities and the capabilities of the processing element are highlighted. The complete hardware and software system has been fully designed and is described. A first working prototype has been built and is now operational.     

The Datran system

The Datran system is designed to serve the specific needs of the data communications user. Data communications terminals almost universally employ a digital format; therefore, an early consideration was the use of digital transmission in lieu of the analog transmission employed by most conventional common-carrier systems. The location of the potential users was examined, this having an important bearing on the transmission media selected. Growth expectancy for future years establishes the base upon which to plan the initial system capacity, the hierarchy of system subassemblies for economical modular growth, and phased construction. The employment of digital channel derivation equipment provides a high channel capacity for a given channel bandwidth as compared to analog transmission and permits the use of highly reliable integrated components at a significant reduction in channel end costs. Time-division multiplexing (TDM) switching with a stored program controller provides reliability and flexibility to meet the changing needs of the data communications user and affords significant savings in space, power, and implementation costs of conventional space-division switches.     

The italsat satellite system

In 1995 the second flight unit of ITALSAT telecommunication satellite will be ary orbit, making operative the ITALSAT telecommunication system after the experimental and preoperational phase performed by ITALSAT F1, which was launched in January 1991 by the Italian Space Agency. A general view of the ITALSAT system is presented with emphasis on the satellite design, the telecommunication mission, the new technologies and the prospects.     

The SL supervisory system

Long-haul transmission systems often require a supervisory system to accomplish such repeater control and monitor functions as switching in standby components and measuring performance parameters. In an undersea system, it is impractical to provide a physically separate channel on which the repeater can send and receive supervisory signals. In SL, this problem is solved by embedding supervisory signals within the main data channels in such a way that they can be extracted or added within the repeater. Supervisory commands are sent to the repeaters on a subcarrier derived by periodically switching between odd and even parity computed over blocks of data. Supervisory responses are sent from the repeaters by low-index phase modulation of the data stream. This paper details the implementation of this scheme, as well as its benefits and limitations.     

The global positioning system

The paper provides a top-level perspective on how the global positioning system works, how its services are used, and delves into the most important technical and geo-political factors affecting its long-term availability in an international setting     

The FLAG cable system

The Fiberoptic Link Around the Globe (FLAG) cable system is a 10 Gb/s synchronous digital hierarchy (SDH) based undersea fiber optic network. When fully operational, FLAG will connect 12 countries with over 120000 voice channels via 27000 km of mostly undersea cable. FLAG will incorporate a new generation of undersea fiber optic system that uses erbium-doped fiber amplifiers and will be jointly supplied by AT&T Submarine Systems Incorporated (SSI) and KDD-Submarine Cable Systems (SCS) Inc. When completed, FLAG will meet or exceed all relevant international performance standards, have greater reliability and availability than previous systems in the region, and conform to all ISO 9000 quality standards with respect to design, development, production, installation, and service     

The silicon-silicon dioxide system

Study of the silicon-silicon dioxide system as a junction between a nearly ideal semiconductor and insulator has aroused both scientific and technological interest. Surface phenomena associated with this system are influenced by contamination and imperfections in the oxide, impurity redistribution in the silicon near the oxide, and finally by additional electronic energy states at the oxide-silicon interface. Over the past few years, the MOS (metal-oxide-semiconductor) approach has been highly developed and is the principal tool for the investigation of silicon surface phenomena. The theory of the ideal MOS capacitor is reviewed followed by a study of its use in the analysis of surface effects. Finally, the three-way relationship of the effect of oxide formation conditions and heat treatment on the properties of the oxidized silicon surface, and the subsequent influence of the properties of this surface on semiconductor device parameters is reviewed.     

THE SYSTEM COMPENSATION OF ISAR

A method for compensating the amplitude-phase distortion of ISAR system is de-scribed.This system compensation can be separated into two parts:the compensation of thesystem before the mixer and the compensation of the system after the mixer.The experimentalresults of the compensation in microwave dark room are given.It is shown that the methodpresented is effective.     

The KidSat project flight system

This paper was written to discuss the technical aspects of granting students in classrooms the ability to explore and study Earth sciences from a unique view of our planet. A high-resolution digital imaging system mounted in the space shuttle cabin window made it possible, in part, to provide real-time student interaction with the space program. This access provided an individual ownership of research and interest in our environment and Earth sciences. The other project technical elements, also key to the program success and real-time student interaction, were the University of California, San Diego (UCSD) web-based mission operations system and the Jet Propulsion Laboratory (JPL) ground data system     

The latch bus driver system

A large and growing fraction of the power in modern VSLI chips is dissipated by the drivers of external bus lines. A novel bus system drastically reduces power and noise by using a central driver chip which periodically attempts to charge and to discharge the bus lines. The transmitters of the selected chip inhibit the charge process for the establishment of a `low' signal. The central driver latches the signal state after the inhibit phase. The authors explain the inhibit driver principle in comparison with the usual push-pull system, present the timing characteristics, and report on the design and the measured results of an experimental central driver chip in full-custom CMOS     

智慧轮椅系统

本套智慧轮椅系统主要解决行动不便者的自由出行和安全出行问题.系统可以通过脑电波结合头部轻微动作控制运动,且融合了遥控和跟随移动功能.系统还具有自动避障功能,以防止用户的误操作导致碰撞等危险发生.在移动过程中,系统会实时上传当前位置、兴奋度以及心率等信息到服务器保存,用户亲属可以通过手机微信、APP或网站访问这些数据,从而辅助用户的健康护理工作.本系统还包括危险自动报警功能,在用户摔倒时及时地通过短信向其亲属报警.     

The NetScript active network system

NetScript is a language system for dynamically programming and deploying protocol software in an active network. NetScript programs are packet flow processors composed out of dataflow components. They can be dynamically dispatched to remote nodes, composed with installed software, and executed to enhance node functions. NetScript has proven useful for implementing a variety of practical network systems including Internet protocol (IP) routers, firewalls, protocol analyzers, traffic shapers, load balancers, various queuing disciplines, intrusion detection systems, Web transport protocols, and IP telephony systems. The paper illustrates the principal concepts of NetScript with an example application, an active IP router that is dynamically extended to provide firewall protection