scholarly journals Fluid Logic Device Using Inversely Arranged Pneumatic Amplifier with Positive Feedback System

1984 ◽  
Vol 20 (5) ◽  
pp. 447-452
Author(s):  
Iwao YAMAMOTO
Keyword(s):  
Positive Feedback ◽  
Feedback System ◽  
Logic Device

Inverter design with positive feedback field-effect transistors

2021 ◽  
Author(s):  
Changhoon Lee ◽  
Changwoo Han ◽  
Changhwan Shin
Keyword(s):  
Positive Feedback ◽  
Computer Aided Design ◽  
Field Effect ◽  
Field Effect Transistors ◽  
Feedback Mechanism ◽  
Silicon On Insulator ◽  
Logic Device ◽  
Device Applications ◽  
Positive Feedback Mechanism ◽  
Switching Devices

Abstract As the physical size of semiconductor devices continues to be aggressively scaled down, feedback field-effect transistors (FBFET) with a positive feedback mechanism among a few promising steep switching devices have received attention as next-generation switching devices. Conventional FBFETs have been studied to explore their device performance. However, this has been restricted to the case of single FBFET; basic circuit designs with FBFETs have not been investigated extensively. In this work, we propose an inverter circuit design with silicon-on-insulator (SOI) FBFETs; we verified this inverter design with mixed-mode technology computer-aided design simulation. The basic principles and mechanisms for designing FBFET inverter circuits are explained because their configuration is different from conventional inverters. In addition, the device parameters necessary to optimize circuit construction are introduced for logic device applications.

The Analysis of Economic and Environmental Feedback System and Proposed Management Policies in Jiuzhaigou

2012 ◽  
Vol 573-574 ◽  
pp. 251-255
Author(s):  
Qi Sheng Chen ◽  
Peng Ge ◽  
Pei Yu Ren
Keyword(s):  
Sustainable Development ◽  
Positive Feedback ◽  
Feedback Loop ◽  
Feedback System ◽  
Feedback Loops ◽  
System Dynamics Model ◽  
Dynamics Model ◽  
The Sustainable Development ◽  
Scenic Spot ◽  
Management Policies

Jiuzhaigou scenic spot (Jiuzhaigou) is an ecological and economic system. The constraints and feedbacks between the economic subsystem and environmental subsystem are very important to the sustainable development. To study this system, the paper creates the system dynamics model about the constraints and feedbacks between economic subsystem and environmental subsystem. The model is made of one growth positive feedback loop of tourism development and two confine positive feedback loops of space constraint and pollution constraint. Then the paper brings up sustainable development management policies in Jiuzhaigou.

Conflict in Unstructured Groups: An Explanation from Control-Theory

1982 ◽  
Vol 51 (1) ◽  
pp. 177-178
Author(s):  
David S. Abbey
Keyword(s):  
Control Theory ◽  
Early Development ◽  
Small Groups ◽  
Negative Feedback ◽  
Positive Feedback ◽  
Feedback System ◽  
The Other ◽  
Two Systems ◽  
Group Members ◽  
Unstructured Groups

The early development of many small groups is marked by conflict and stress between two sub-groups. It is argued that each sub-group is governed by a different feedback system: one reduces deviations from plans (negative feedback system), whereas the other seeks novelty and spontaneity (positive feedback system). The two systems are incompatible and result in ‘storming’ or hostility among group members.

scholarly journals Effects of Endogenous Proteins and microRNA Target Sequence in a Positive Feedback System

2012 ◽  
Vol 35 (9) ◽  
pp. 1534-1538 ◽  
Author(s):  
Genki N. Kanda ◽  
Ryohei Togashi ◽  
Hideyoshi Harashima ◽  
Hiroyuki Kamiya
Keyword(s):  
Positive Feedback ◽  
Feedback System ◽  
Target Sequence ◽  
Microrna Target ◽  
Endogenous Proteins

scholarly journals BMP4 Signaling Activates the Wnt-Lin28A-Blimp1-Wnt Positive Feedback Pathway to Promote Primordial Germ Cell Formation via Altering H3K4me2

2020 ◽  
Author(s):  
Qisheng Zuo ◽  
Yani Zhang ◽  
Guohong Chen ◽  
Bichun Li
Keyword(s):  
Wnt Signaling ◽  
Positive Feedback ◽  
Primordial Germ Cells ◽  
Primordial Germ Cell ◽  
Cell Formation ◽  
Feedback System ◽  
Developmental Characteristics ◽  
Technical Basis ◽  
Feedback Pathway

Abstract (Background) The unique developmental characteristics of bird primordial germ cells (PGC) have enabled genetic engineering–based breeding and restoration of endangered birds via transplantation in vitro. However, the limited number of PGC has limited their application. Thus, there is an urgent need to elucidate the mechanism of PGC formation in vitro to enhance its efficiency. (Results) Here, we confirmed that activation of BMP4 and Wnt signaling (Wnt5A/β-catenin/TCF7L2) is critical for PGC formation via RNA-seq (ESCs, PGC and SSCs) and in vitro induction models. Wnt signaling activated via BMP4 in turn activates transcription of Lin28A by inducing β-catenin to compete with LSD1 for binding to the transcription factor TCF7L2, causing LSD1 to dissociate from the Lin28A promoter and enhanced H3K4me2 methylation in this region. Lin28A promotes PGC formation by inhibiting gga-let7a-3p maturation to initiate Blimp1 expression. Interestingly, expression of Blimp1 helped sustain Wnt5A expression by preventing LSD1 binding to the Wnt5A promoter. We thus elucidated a positive feedback pathway involving Wnt-Lin28-Blimp1-Wnt, with BMP4 functioning as an activator that ensures PGC formation. (Conclusion) In summary, our study clarified the molecular mechanism by which BMP4 and Wnt signaling regulate PGC formation via a positive feedback system. Our data provide both a theoretical and technical basis for studies aimed at enhancing the generation of PGC in vitro.

scholarly journals Alternating Positive and Negative Feedback Control Model Based on Catastrophe Theories

Mathematics ◽  
2021 ◽  
Vol 9 (22) ◽  
pp. 2878
Author(s):  
Wenkai Huang ◽  
Fobao Zhou ◽  
Tao Zou ◽  
Puwei Lu ◽  
Yihao Xue ◽  
...  
Keyword(s):  
Feedback Control ◽  
Negative Feedback ◽  
Positive Feedback ◽  
Learning Rule ◽  
Lyapunov Stability Theory ◽  
Response Speed ◽  
Feedback System ◽  
Control Model ◽  
Positive And Negative Feedback ◽  
Negative Feedback Control

In automatic control systems, negative feedback control has the advantage of maintaining a steady state, while positive feedback control can enhance some activities of the control system. How to design a controller with both control modes is an interesting and challenging problem. Motivated by it, on the basis idea of catastrophe theories, taking positive feedback and negative feedback as two different states of the system, an adaptive alternating positive and negative feedback (APNF) control model with the advantages of two states is proposed. By adaptively adjusting the relevant parameters of the constructed symmetric catastrophe function and the learning rule based on error and forward weight, the two states can be switched in the form of catastrophe. Through the Lyapunov stability theory, the convergence of the proposed adaptive APNF control model is proven, which indicates that system convergence can be guaranteed by selecting appropriate parameters. Moreover, we present theoretical proof that the negative feedback system with negative parameters can be equivalent to the positive feedback system with positive parameters. Finally, the results of the simulation example show that APNF control has satisfactory performance in response speed and overshoot.

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