Sähköisen ja optisen signaalin käyttö samalla piirilevyllä

Työssä tutkittiin sähköisen ja optisen signaalin siirtoa samalla piirilevyllä. Optisen siirtotien komponentit ja niiden toiminta esiteltiin teoriakappaleessa. Valosignaalin vaimentumisilmiö selitettiin pääasiassa johtuvan absorption ja sironnan vaikutuksesta. Sironnan ja absorption vaikutusta valokuidussa käytettävään aallonpituusalueeseen tutkittiin ja esiteltiin valon yleisin modulaatiomenetelmä WDM. Työssä esiteltiin myös dispersion aiheuttama aikahajonta. Optisen signaalin siirrossa piirilevyllä keskityttiin valokanava- ja free-space-siirtoon. Valokanavamateriaalin vaikutusta heijastuksiin optisessa tiedonsiirrossa piirilevyllä tutkittiin. Nykyisten piirilevyjen tuotantomenetelmien käytön mahdollisuutta valokanavapiirilevyn valmistuksessa tutkittiin eri materiaaleille. Moduulien sisäisten tiedonsiirtoteiden integroinnin yleistymistä tulevaisuudessa perusteltiin. Lopuksi työssä esiteltiin kolme uutta keksintöä liittyen optiseen tiedonsiirtoon. Tarkoituksena oli esittää alan moninaisuutta ja uusien sovellusten mahdollisuuksia.

Improving the performance of a dismounted Future Force Warrior by means of C4I2SR

This thesis comprises seven peer-reviewed articles and examines systems and applications suitable for increasing Future Force Warrior performance, minimizing collateral damage, improving situational awareness and Common Operational Picture. Based on a literature study, missing functionalities of Future Force Warrior were identified and new ideas, concepts and solutions were created as part of early stages of Systems of Systems creation. These introduced ideas have not yet been implemented or tested in combat and for this reason benefit analyses are excluded. The main results of this thesis include the following: A new networking concept, Wireless Polling Sensor Network, which is a swarm of a few Unmanned Aerial Vehicles forming an ad-hoc network and polling a large number of fixed sensor nodes. The system is more robust in a military environment than traditional Wireless Sensor Networks. A Business Process approach to Service Oriented Architecture in a tactical setting is a concept for scheduling and sharing limited resources. New components to military Service Oriented Architecture have been introduced in the thesis. Other results of the thesis include an investigation of the use of Free Space Optics in tactical communications, a proposal for tracking neutral forces, a system for upgrading simple collaboration tools for command, control and collaboration purposes, a three-level hierarchy of Future Force Warrior, and methods for reducing incidents of fratricide.

Det planlagda och det som visar sig : klasslärarstuderandes syn på undervisning i teknisk slöjd

Sloyd as an activity concretizes man’s ability to, with the help of mind and body, reshape materials into objects and change her conditions for survival. The sloyd actor outside school works when the spirit moves her, while the pupil in school is expected to sloyd regardless of motivation. Subject teachers become experts on sloyd in educational settings, while the qualification requirements may set the class teachers’ voluntariness within parenthesis. All class teachers qualify to teach all core subjects of the national curriculum in Finland from preschool to grade six. The aim of the current thesis is to deepen the knowledge on how the science of sloyd education can support class teacher students’ future teaching in sloyd. In the empirical part of the study, Swedish-speaking Finnish class teacher students’ views on technical sloyd as one of their future subjects for teaching are examined. The class teacher’s qualifying skills in teaching technical sloyd are expected to take shape during only a few ECTS study points. The teacher students’ experience of the subject from the pupil’s perspective is supposed to move into a budding teacher subject. In a research-based teacher education, self-reflection and reflection as a dialogue are extended aided by research results. Intuitive thinking interplays with rational thinking during this time. The teacher student’s approach to make use of the autonomous free space in teaching is, in the current thesis, as considerations where the individual weighs the pros and cons in relation to various phenomena in sloyd and the school overall. The basis for an individual autonomy is shaped and is expected to interplay on the common arena of autonomy. In the exercise of their profession, the class teacher teaching sloyd is expected to oscillate between the sloyd educational practice and theory. The first step in this movement within the teacher education is the coverage of a selection of theories during the studies. The empirical part of the study is carried out at two separate occasions with directed open-ended interviews with fifteen class teacher students in the beginning and end of their first year of study. The data was analysed with a hermeneutic approach and a qualitatively oriented approach to content analysis. The results are mirrored against theory within the science of sloyd education. The results show that class teacher students have a versatile view of educational sloyd. The overall results overthrow parts of the researcher’s pre-understanding. The viewpoint of the students seems to broaden from a merely manual activity to seeing sloyd as an educational activity. In order for the results to gain significance in the teacher education of the future, a line of reasoning is conducted in order to recommend an extended dialogue and thirteen possible themes for enriching discussions are put forth as a result of the present study. The extended dialogue focuses on that teacher education should make conscious ventures to create opportunities for the students to take part in effective discussions on the subject of sloyd, complementing the existing dialogue between the teacher educator and the students. This thesis lends support to reflections on the following aspects of educational sloyd in these dialogues: the reasons for why the sloyd subject exists, the ambitions of the subject, the content and organization of the subject for students as well as for the teacher educators.

Design Space Exploration for MPSoC Architectures

Multiprocessor system-on-chip (MPSoC) designs utilize the available technology and communication architectures to meet the requirements of the upcoming applications. In MPSoC, the communication platform is both the key enabler, as well as the key differentiator for realizing efficient MPSoCs. It provides product differentiation to meet a diverse, multi-dimensional set of design constraints, including performance, power, energy, reconfigurability, scalability, cost, reliability and time-to-market. The communication resources of a single interconnection platform cannot be fully utilized by all kind of applications, such as the availability of higher communication bandwidth for computation but not data intensive applications is often unfeasible in the practical implementation. This thesis aims to perform the architecture-level design space exploration towards efficient and scalable resource utilization for MPSoC communication architecture. In order to meet the performance requirements within the design constraints, careful selection of MPSoC communication platform, resource aware partitioning and mapping of the application play important role. To enhance the utilization of communication resources, variety of techniques such as resource sharing, multicast to avoid re-transmission of identical data, and adaptive routing can be used. For implementation, these techniques should be customized according to the platform architecture. To address the resource utilization of MPSoC communication platforms, variety of architectures with different design parameters and performance levels, namely Segmented bus (SegBus), Network-on-Chip (NoC) and Three-Dimensional NoC (3D-NoC), are selected. Average packet latency and power consumption are the evaluation parameters for the proposed techniques. In conventional computing architectures, fault on a component makes the connected fault-free components inoperative. Resource sharing approach can utilize the fault-free components to retain the system performance by reducing the impact of faults. Design space exploration also guides to narrow down the selection of MPSoC architecture, which can meet the performance requirements with design constraints.

Simulation of the Interaction Mean Free Path between Neutrons and TRISO Particles

The interaction mean free path between neutrons and TRISO particles is simulated using scripts written in MATLAB to solve the increasing error present with an increase in the packing factor in the reactor physics code Serpent. Their movement is tracked both in an unbounded and in a bounded space. Their track is calculated, depending on the program, linearly directly using the position vectors of the neutrons and the surface equations of all the fuel particles; by dividing the space in multiple subspaces, each of which contain a fraction of the total number of particles, and choosing the particles from those subspaces through which the neutron passes through; or by choosing the particles that lie within an infinite cylinder formed on the movement axis of the neutron. The estimate from the current analytical model, based on an exponential distribution, for the mean free path, utilized by Serpent, is used as a reference result. The results from the implicit model in Serpent imply a too long mean free path with high packing factors. The received results support this observation by producing, with a packing factor of 17 %, approximately 2.46 % shorter mean free path compared to the reference model. This is supported by the packing factor experienced by the neutron, the simulation of which resulted in a 17.29 % packing factor. It was also observed that the neutrons leaving from the surfaces of the fuel particles, in contrast to those starting inside the moderator, do not follow the exponential distribution. The current model, as it is, is thus not valid in the determination of the free path lengths of the neutrons.

Defining Contexts in Context-Free Grammars

This thesis introduces an extension of Chomsky’s context-free grammars equipped with operators for referring to left and right contexts of strings.The new model is called grammar with contexts. The semantics of these grammars are given in two equivalent ways — by language equations and by logical deduction, where a grammar is understood as a logic for the recursive definition of syntax. The motivation for grammars with contexts comes from an extensive example that completely defines the syntax and static semantics of a simple typed programming language. Grammars with contexts maintain most important practical properties of context-free grammars, including a variant of the Chomsky normal form. For grammars with one-sided contexts (that is, either left or right), there is a cubic-time tabular parsing algorithm, applicable to an arbitrary grammar. The time complexity of this algorithm can be improved to quadratic,provided that the grammar is unambiguous, that is, it only allows one parsefor every string it defines. A tabular parsing algorithm for grammars withtwo-sided contexts has fourth power time complexity. For these grammarsthere is a recognition algorithm that uses a linear amount of space. For certain subclasses of grammars with contexts there are low-degree polynomial parsing algorithms. One of them is an extension of the classical recursive descent for context-free grammars; the version for grammars with contexts still works in linear time like its prototype. Another algorithm, with time complexity varying from linear to cubic depending on the particular grammar, adapts deterministic LR parsing to the new model. If all context operators in a grammar define regular languages, then such a grammar can be transformed to an equivalent grammar without context operators at all. This allows one to represent the syntax of languages in a more succinct way by utilizing context specifications. Linear grammars with contexts turned out to be non-trivial already over a one-letter alphabet. This fact leads to some undecidability results for this family of grammars

The effects of added glycerol or unprotected free fatty acids or a combination of the two on silage intake, milk production, rumen fermentation and diet digestibility in cows given grass silage based diets

Selostus: Väkirehuun lisätyn glyserolin tai vapaiden rasvahappojen tai näiden yhdistelmän vaikutus maidontuotantoon ja pötsifermentaatioon ruokittaessa lypsylehmiä säilörehuun perustuvalla ruokinnalla

Effect of different potassium sources on the seasonal variation of potassium and free polyamines in scots pine needles

Summary