A comprehensive simulation model for the infant-incubator-feedback system was developed in a Matlab/Simulink® environment to investigate all heat exchange relationships, variables and factors that have an influence on the overall thermo-neutrality of the environment. The model was also used to determine the benefits and limitations of using a convectively heated single-walled incubator in nursing preterm infants with very low birth weight < 1000 grams and low gestational age 28 weeks. The infant was modelled as one-lump with two layers; core and skin. The infant shape was approximated to a cylinder. The model incorporated all compartments of the infant-incubator system including core, skin, incubator air space, mattress, incubator walls, air-circulating fan, heating element, added oxygen (for resuscitation purposes), and humidification chamber, which has not previously been considered. The results of the simulation were in terms of the temperature variation over time, of the following parts of the system: core and skin temperatures and incubator air space temperature. Results of the simulation with added humidity showed that the body temperature of a 900 gram infant, with an initial body temperature of 35.5 ºC, did not reach the thermo-neutral range between 36.5-37.5 ºC in two hours, on air mode. Whereas, on skin mode, both core and skin temperature reached to 36.87 ºC and 36.5 ºC in two hours, and thus a thermo-neutral environment was achieved. These outcomes are consistent with clinical empirical reports. The simulation model is a closed-loop system with a PID controller for each mode; air servo controlled and skin servo controlled. The controller parameters were virtually estimated by the Zeigler-Nichols Method as real values were not available. Nevertheless, the overall stability of the whole system has been achieved by applying a step input which was verified by the Root Locus Method.

A comprehensive simulation model for the infant-incubator-feedback system was developed in a Matlab/Simulink® environment to investigate all heat exchange relationships, variables and factors that have an influence on the overall thermo-neutrality of the environment. The model was also used to determine the benefits and limitations of using a convectively heated single-walled incubator in nursing preterm infants with very low birth weight < 1000 grams and low gestational age 28 weeks. The infant was modelled as one-lump with two layers; core and skin. The infant shape was approximated to a cylinder. The model incorporated all compartments of the infant-incubator system including core, skin, incubator air space, mattress, incubator walls, air-circulating fan, heating element, added oxygen (for resuscitation purposes), and humidification chamber, which has not previously been considered. The results of the simulation were in terms of the temperature variation over time, of the following parts of the system: core and skin temperatures and incubator air space temperature. Results of the simulation with added humidity showed that the body temperature of a 900 gram infant, with an initial body temperature of 35.5 ºC, did not reach the thermo-neutral range between 36.5-37.5 ºC in two hours, on air mode. Whereas, on skin mode, both core and skin temperature reached to 36.87 ºC and 36.5 ºC in two hours, and thus a thermo-neutral environment was achieved. These outcomes are consistent with clinical empirical reports. The simulation model is a closed-loop system with a PID controller for each mode; air servo controlled and skin servo controlled. The controller parameters were virtually estimated by the Zeigler-Nichols Method as real values were not available. Nevertheless, the overall stability of the whole system has been achieved by applying a step input which was verified by the Root Locus Method.

Purpose: The construction sector has for many years been criticized for being ineffective, non-competitive and being expensive. Swedish construction firms needs to work with their experience feedback systems. But unfortunately it lacks tradition and experiences with this kind of work with experience feedback. Work in the construction sector usually is defined as craftmanship. Which means that errors are corrected as quickly as possible without understanding and analyzing the underlying causes of the errors and thus be able to control their production processes. The purpose of this study is to bring foward a theoretical model over information flows that could increase the efficiency of the experience feedback between construction projects. Method: The study’s approach was through a qualitative case study. Qualitative case study was chosen due to the need of a thorough analysis of the problem. The report’s theoretical framework is produced from a literature study which focused on experience feedback, knowledge management, incentives and motivation. The empirical accumulation consisted of six interviews conducted by the type of semi-structured and a document analysis. Findings: In the current situation oral feedback is the most common experience feedback from the construction site. Systems regarding experience feedback is not used due to lack of knowledge of the systems and information about how the work with experience feedback should be done is non-existent. Work with experience feedback does not take place continuously during the project and does not have any shall batch. There is no structure, responsibilities and guidelines regarding how the work with experience feedback should be done. This leads to uncertainty among service men concerning the definition of experience feedback. Due to that no information has been released to service men about how the systems works or what’s in the systems motivation to work with the experience feedback systems are failing. Implications: The conclusions of this report is that a knowledge bank should be made available to all service men within the company, from the knowledge bank experiences are reported in and out. During the project continuosly work should be done regarding experience feedback through meetings and at each construction site a responsible person should handle the reporting of experiences. There should be clear structures and guidelines of what the work with experience feedback includes. A responsible person should be handling the knowledge bank and ensure that only relevant information stores in the knowledge bank. Limitations: The report concerns incentive and motivation which is applicable in any organization, this promotes a generally valid result for the case study. The report delimitates from all database structures which are considered as positive due to the time it takes to analyze and make these structures. This would have indirectly been taking time from the analysis of the experience feedback systems and would make the study’s result less credible. / Syfte: Byggsektorn har under många år fått utstå kritik för att vara ineffektiv, konkurrensfattig samt ha en hög prissättning. Svenska byggentreprenader behöver därför jobba med sina erfarenhetssystem men tyvärr saknas traditionen och även erfarenheten med att arbeta med detta. Arbetet inom byggbranschen brukar kallas hantverkskunnande. Vilket innebär att fel rättas till så snabbt som möjligt utan att förstå och analysera de bakomliggande orsakerna till felen och på så sätt kunna styra sina produktionsprocesser. Målet med studien är att framställa en teoretisk modell över informationsflöden som skulle kunna effektivisera erfarenhetsåterföringen mellan byggprojekt. Metod: Studiens angreppssätt var genom en kvalitativ fallstudie. Kvalitativ fallstudie valdes på grund av att studien kräver en fördjupad analys av problemet. Rapportens teoretiska ramverk är framtaget från en litteraturstudie där fokus ligger vid erfarenhetsåterföring, knowledge management, incitament och motivation. Empiriinsamlingen bestod av sex stycken intervjuer som genomfördes av typen semistrukturerade och en dokumentanalys. Resultat: I dagsläget används mest muntlig erfarenhetsåterföring från produktionen. Systemen för erfarenhetsåterföring används inte då kännedomen om systemen är bristfällig och information om hur arbetet med erfarenhetsåterföring ska ske är obefintlig. Arbetet med erfarenhetsåterföring sker inte kontinuerligt under projektets gång och har ingen egen skallsats. Det saknas struktur, ansvar och riktlinjer om hur arbetet med erfarenhetsåterföring ska gå till vilket leder till en ovisshet bland tjänstemännen om vad arbetet med erfarenhetsåterföring innebär. Då ingen information har kommit ut till tjänstemännen om hur erfarenhetsåterföringssystemen fungerar eller vad som finns i systemen leder detta till att motivationen med att arbeta med erfarenhetsåterföringssystemen blir sviktande. Konsekvenser: Slutsatserna för denna rapport är att en kunskapsbank ska göras tillgänglig för alla tjänstemän inom företag där erfarenheter rapporteras in och ut. Under projektets gång ska det arbetas kontinuerligt med erfarenhetsåterföring genom möten och det ska finnas en ansvarsfördelning över in- och utrapportering av erfarenheter inom produktionen. Det ska finnas en tydlig struktur och tydliga riktlinjer ute i produktionen om vad som ska ingå i arbetet med erfarenhetsåterföring. En ansvarig person ska finnas för erfarenhetsåterföringen som ansvarar för kunskapsbanken och ser till att relevant information kommer in i systemet. Begränsningar: Rapporten berör incitament och motivation som är applicerbart i alla organisationer vilket främjar ett generellt giltigt resultat. Rapporten avgränsades från eventuella databasstrukturer vilket anses som positivt då mycket tid hade behövts för att skapa mappstrukturer och ordning i modellens kunskapsbank. Detta hade indirekt tagit tid från fördjupandet

Information asymmetries, proprietary knowledge that one party in a trade holds over another party, in electronic markets might cause a loss in market efficiency and market failure. Reputation mechanisms may provide a means to reduce the effects of information asymmetry and prevent possible market failure. Feedback rating systems are among potential mechanisms to develop reputations. They are often used in naturalistic environment electronic market studies. Reputation mechanisms are difficult to assess, however, in naturalistic research settings since the researcher cannot control the many variables of interest. To control the variables, this study used an experimental research setting. The setting enabled buyer and seller values to be controlled to study the impact of reputation mechanisms on market efficiency and price premiums. A theory from economics, the induced value theory, was used to modify subject preferences through the use of a reward medium. The experimental market was implemented in a classroom environment patterned on Holt's (1999) design. University students accessed a Website that enabled a fictitious market in which the students acted as buyers and sellers of a fictitious product. The product is valued with a fictitious currency which has no real-world value. This allows for values to be induced. Two market control conditions were established, a full information near 100% efficient condition, which is the `ceiling' expectation, and a fairly low efficient condition in which no seller or product grade information was available to buyers, is the `floor' or "Lemons" condition. Two treatments, `cheaptalk', where sellers can make unverifiable product claims, and `feedback', where seller identity and historical ratings are available to buyers, were tested. The impact of asymmetric information on market efficiency was evaluated, as was the impact of a feedback rating mechanism on enhancing market efficiency. Analysis of the experiment results indicate that the treatments can be ordered as: Full Information-Feedback-Cheaptalk-Lemons, with regard to the affect of information on market efficiency.

In this paper, the problem of dual actuation in the atomic force microscope (AFM) is analyzed. The use of two actuators to balance the trade-off between bandwidth, range, and precision has been recently extended to nano-positioning systems. Despite existing demands, this concept undergoes fundamental limitations towards its extension to AFMs. This is attributed to the non-conventional requirement imposed on the control signal response, as it used to create the image of the characterized surface. / Singapore-MIT Alliance (SMA)

Today, except for mathematical operations, our brain functions much faster and more efficient than any supercomputer. It is precisely this form of information processing in neural networks that inspires researchers to create systems that mimic the brain’s information processing capabilities. In this thesis we propose a novel approach to implement these alternative computer architectures, based on delayed feedback. We show that one single nonlinear node with delayed feedback can replace a large network of nonlinear nodes. First we numerically investigate the architecture and performance of delayed feedback systems as information processing units. Then we elaborate on electronic and opto-electronic implementations of the concept. Next to evaluating their performance for standard benchmarks, we also study task independent properties of the system, extracting information on how to further improve the initial scheme. Finally, some simple modifications are suggested, yielding improvements in terms of speed or performance.

In this work, we introduce several novel approaches to feedback controller design, known collectively as the “Robust Bode” methods, which adapt classical control principles to a modern robust control (H∞) framework. These methods, based on specially modified Bode diagrams extend familiar frequency-domain controller design techniques to linear and nonlinear, single–input/single– output (SISO) and multi–input/multi–output (MIMO) systems with parametric and/or unstructured uncertainties. In particular, we introduce the Contoured Robust Controller Bode (CRCBode) plots which show contours (level-sets) of a robust metric on the Bode magnitude and phase plots of the controller. An iterative loop shaping design procedure is then employed in an attempt to eliminate all intersections of the controller frequency response with certain forbidden regions indicating that a robust stability and performance criteria is satisfied. For SISO systems a robust stability and performance criterion is derived using Nyquist arguments leading to the robust metric used in the construction of the CRCBode plots. For open-loop unstable systems and for non-minimum phase systems the Youla parametrization of all internally stabilizing controllers is used to develop an alternative Robust Bode method (QBode). The Youla parametrization requires the introduction of state-space methods for coprime factorization, and these methods lead naturally to an elegant connection between linear-quadratic Gaussian (LQG) optimal control theory and Robust Bode loop-shaping controller design. Finally, the Robust Bode approach is extended to MIMO systems. Utilizing a matrix norm based robustness metric on the MIMO CRCBode plots allows cross-coupling between all input/output channels to be immediately assessed and accounted for during the design process, making sequential MIMO loop-shaping controller design feasible.

Automated short-answer marking cannot 'guarantee' 100% agreement between the marks generated by a software system and the marks produced separately by a human. This problem has prevented automated marking systems from being used in high-stake short-answer marking. Given this limitation, can an automated short-answer marking system have any practical application? This thesis describes how an automated short-answer marking system, called IndusMarker, can be effectively used to improve learning and teaching.The design and evaluation of IndusMarker are also presented in the thesis. IndusMarker is designed for factual answers where there is a clear criterion for answers being right or wrong. The system is based on structure matching, i.e. matching a pre-specified structure, developed via a purpose-built structure editor, with the content of the student's answer text. An examiner specifies the required structure of an answer in a simple purpose-designed language called Question Answer Markup Language (QAML). The structure editor ensures that users construct correct required structures (with respect to QAML's syntax and informal semantics) in a form that is suitable for accurate automated marking.

As we begin to analyze and construct extremely complex systems, a theory for understanding and designing the underlying architecture becomes very important. To move in the direction of a precise theory of architecture, this thesis will provide some concrete tools to analyze and design complex systems with a given network structure. The first main result of this thesis analyzes the vulnerability of a system and shows that a system's vulnerability depends on its network structure. We will consider destabilization attacks acting on a single link in a system's logical interconnection structure. The concept of a vulnerable link is characterized and necessary and sufficient conditions for identifying these links are provided. The vulnerability of various system architectures are then characterized by the vulnerability of their weakest link, and it is shown that every transfer function has a completely secure architecture with no vulnerable links. The second part of this thesis focuses on synthesizing controllers with a specified network structure. It presents a new approach to distributed controller design that exploits the dynamical structure function representation of linear time invariant systems to characterize the structure of a system. The design technique sequentially constructs each link in an arbitrary controller signal structure, and the main theorem proves that either the resulting controller is stabilizing or that no controller with the desired structure can stabilize the system.

Актуальность темы магистерской диссертации обусловлена всевозрастающей ролью автоматизации работы и обратной связи между студентами и преподавателем. Эффективное управление планированием обратной связи является залогом успешной работы, получение максимальной пользы при минимальных временных и финансовых издержках. Практическая значимость заключается в том, что разработанные рекомендации позволят повысить эффективность обратной связи студентов с преподавателем, сократить трудозатраты персонала, снизить расходы и издержки, связанные с обработкой анкет вручную. / The relevance of the topic of master's thesis is due to the ever-increasing role of work automation and feedback between students and the teacher. Effective management of feedback planning is the key to successful work, getting maximum benefit with minimal time and financial costs. The practical importance lies in the fact that the developed recommendations will improve the feedback of students with the teacher, reduce the labor costs of staff, reduce costs and costs associated with the processing of questionnaires manually.