Using Linear Superposition to Solve Multiple Heat Source Transient Thermal Problems

Author(s):  
David T. Billings ◽  
Roger P. Stout

For many years engineers have been using linear superposition to solve steady state thermal problems with multiple-heat-source systems. Predicting transient response of single-heat-source systems has been performed using R-C Foster networks with reasonable success. In most real applications there are multiple heat sources that are interacting perhaps in very complex ways in the time domain. Being able to simulate these interactions using a spreadsheet tool or a circuit simulator may be very advantageous to a device or application engineer designing or evaluating an application design. Using an RC-network model of a system to represent the individual transient response curves, we’ll show how to do this bookkeeping (and all the other calculations) for a simple system using Microsoft Excel. We’ll also see how to set up this sort of problem in a circuit simulator.

1977 ◽  
Vol 16 (02) ◽  
pp. 112-115 ◽  
Author(s):  
C. O. Köhler ◽  
G. Wagner ◽  
U. Wolber

The entire field of information processing in medicine is today already spread out and branched to such an extent that it is no longer possible to set up a survey on relevant literature as a whole. But even in narrow parts of medical informatics it is hardly possible for the individual scientist to keep up to date with new literature. Strictly defined special bibliographies on certain topics are most helpful.In our days, problems of optimal patient scheduling and exploitation of resources are gaining more and more importance. Scientists are working on the solution of these problems in many places.The bibliography on »Patient Scheduling« presented here contains but a few basic theoretical papers on the problem of waiting queues which are of importance in the area of medical care. Most of the papers cited are concerned with practical approaches to a solution and describe current systems in medicine.In listing the literature, we were assisted by Mrs. Wieland, Mr. Dusberger and Mr. Henn, in data acquisition and computer handling by Mrs. Gieß and Mr. Schlaefer. We wish to thank all those mentioned for their assistance.


2019 ◽  
Vol 130 (629) ◽  
pp. 1384-1415 ◽  
Author(s):  
Ralph Hertwig ◽  
Michael D Ryall

ABSTRACT Thaler and Sunstein (2008) advance the concept of ‘nudge’ policies—non-regulatory and non-fiscal mechanisms designed to enlist people's cognitive biases or motivational deficits so as to guide their behaviour in a desired direction. A core assumption of this approach is that policymakers make artful use of people's cognitive biases and motivational deficits in ways that serve the ultimate interests of the nudged individual. We analyse a model of dynamic policymaking in which the policymaker's preferences are not always aligned with those of the individual. One novelty of our set-up is that the policymaker has the option to implement a ‘boost’ policy, equipping the individual with the competence to overcome the nudge-enabling bias once and for all. Our main result identifies conditions under which the policymaker chooses not to boost in order to preserve the option of using the nudge (and its associated bias) in the future—even though boosting is in the immediate best interests of both the policymaker and the individual. We extend our analysis to situations in which the policymaker can be removed (e.g., through an election) and in which the policymaker is similarly prone to bias. We conclude with a discussion of some policy implications of these findings.


2019 ◽  
Vol 1 (1) ◽  
pp. 179-195 ◽  
Author(s):  
Tina Besley

This article explores concepts of teacher responsibility, accountability, being in loco parentis, and responsibilization as many advanced capitalist societies have dropped policies and practices that were set up in the mid 19th century after the Great Depression in the welfare state under Keynesian economics. Since the early 1980s most of these states have adopted neoliberal policies and market rationality for all aspects of social policy including education. Under neoliberalism, the subject theorised by Homo economicus, is one that is theorised as a rational autonomous individual, with its responsibilized behavior underpinning much of how not only teachers but students now are compleed to behace and perform. These have resulted in major shifts in attitudes to professionalism of teachers, in responsibilising individuals and so have impacted on subjectivity as the state has pulled back from all manner of social provision and has responsibilized the individual to be a consumer-citizen, a prudential and entrepreneurial self even in terms of education. The upshot is increasing use of audits, checklists and accountability regimes for teachers who are becoming increasingly a de-professionalised in a low-trust managerialist environment with students as consumers.


2006 ◽  
Vol 113 ◽  
pp. 167-172
Author(s):  
Maik Mracek ◽  
Tobias Hemsel ◽  
Piotr Vasiljev ◽  
Jörg Wallaschek

Rotary ultrasonic motors have found broad industrial application in camera lens drives and other systems. Linear ultrasonic motors in contrast have only found limited applications. The main reason for the limited range of application of these very attractive devices seems to be their small force and power range. Attempts to build linear ultrasonic motors for high forces and high power applications have not been truly successful yet. To achieve drives, larger force and higher power, and multiple miniaturized motors can be combined. This approach, however, is not as simple as it appears at first glance. The electromechanical behavior of individual motors differs slightly due to manufacturing and assembly tolerances. Individual motor characteristics are strongly dependent on the driving parameters (frequency, voltage, temperature, pre-stress, etc.) and the driven load and the collective behavior of the swarm of motors is not just the linear superposition of the individual drive’s forces.


Activity of the plant requires a great deal of work and human asset and requires a ton of diligent work and persistence as the individual needs to take note of every single an incentive at various occasions by taking readings physically. With the advancement of Industrial Automation, fluid level control framework has been generally utilized in different fields. In this paper, in light of PLC a control framework is set up by PID calculation and this control framework can alter two diverse fluid levels consequently. On the off chance that there are two distinct kinds of fluids with various densities in an equivalent tank and so as to isolate those two fluids, Level control framework dependent on SCADA and PLC is actualized. This framework satisfies splendidly the need of various fluid level control framework in industry, and it brings advantageous and exact for controlling. The proposed framework gives the fluid Level control, with the assistance of Programmable Logic Controllesr (PLCs), and Supervisory Control and Data Acquisition (SCADA).


COVID ◽  
2021 ◽  
Vol 1 (4) ◽  
pp. 717-727
Author(s):  
Parastoo Kheiroddin ◽  
Magdalena Gründl ◽  
Michael Althammer ◽  
Patricia Schöberl ◽  
Linda Plail ◽  
...  

(1) Background: With vaccination and new variants of SARS-CoV-2 on the horizon, efficient testing in schools may enable prevention of mass infection outbreaks, keeping schools safe places and buying time until decisions on feasibility and the necessity of vaccination in children and youth are made. We established, in the course of the WICOVIR (Where Is the COrona VIRus) study, that gargle-based pool-PCR testing offers a feasible, efficient, and safe testing system for schools in Germany when applied by central university laboratories. (2) Objectives: We evaluated whether this approach can be implemented in different rural and urban settings. (3) Methods: We assessed the arrangements required for successful implementation of the WICOVIR approach in a variety of settings in terms of transport logistics, data transfer and pre-existing laboratory set-up, as well as the time required to establish the set-up. (4) Results: We found that once regulatory issues have been overcome, all challenges pertaining to logistics, data transfer, and laboratory testing on different platforms can be solved within one month. Pooling and depooling of samples down to the individual test result were achievable within one working day in all settings. Local involvement of the community and decentralized set-ups were keys for success. (5) Conclusion: The WICOVIR gargle-based pool-PCR system is so robust and simple that it can be implemented within one month in all settings now or in future pandemics.


2013 ◽  
Vol 3 (1) ◽  
pp. 54-61 ◽  
Author(s):  
Dr. Anuradha Jain

Retailing is the interface between the producer and the individual consumer buying for personal consumption. As such, retailing is the last link that connects the individual consumer with the manufacturing and distribution chain. Indian retail industry is one of the sunrise sectors with huge growth potential. However, in spite of the recent developments in retailing and its immense contribution to the economy, retailing continues to be the least evolved industries and the growth of organised retailing in India has been much slower as compared to rest of the world. This paper captures the existing retail scenario in India with regard to organized and un-organized retail and presents the limitations of the current set-up along with the experiences of domestic players. The paper discusses about opening up of the multibrand retail sector to foreign direct investment by the government. The rationale for retail reforms and challenges to be addressed by the retail sector are discussed. FDI in Retail is like an allopathic medicine It would deliver quick results & would not work as hit & trial like Homeopath. Government must go for Policy Mix to avoid its side effects. It will require various changes in internal policies also. The whole process must be made socially & economically useful.It will be better to follow the Chinese model of caution and hurrying slowly. China took over 12years to liberalise its FDI regime and in stages with reversals as well. The Chinese retail environment is 20years ahead of us. Looking at their market today can give us a rough idea of how FDI in multi brand retail in India might pan out in the medium term and long term period.


2012 ◽  
Vol 56 (04) ◽  
pp. 215-233
Author(s):  
Johan T. Tuitman ◽  
Šime Malenica ◽  
Riaan van't Veer

The concept of "generalized modes" is to describe all degrees of freedom by mode shapes and not using any predefined shape, like rigid body modes. Generalized modes in seakeeping computations allow one to calculate the response of a single ship, springing, whipping, multibody interaction, etc., using a uniform approach. The generalized modes have already been used for frequency-domain seakeeping calculations by various authors. This article extents the generalized modes methodology to be used for time-domain seakeeping computations, which accounts for large-amplitude motions of the rigid-body modes. The time domain can be desirable for seakeeping computations because it is easy to include nonlinear load components and to compute transient response, like slamming and whipping. Results of multibody interaction, two barges connected by a hinge, whipping response of a ferry resulting from slamming loads, and the response of a flexible barge are presented to illustrate the theory.


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