Kahden lämmitysjärjestelmiä valmistavan tuotantoyksikön toimintojen yhdistäminen kustannustehokkuuden lisäämiseksi

Tämä työ käsittelee Oilon Oy:n tehtaan layout -suunnittelua, kun yhdistetään kaksi eri kiinteistössä toimivaa tuotantoyksikköä saman katon alle. Yksiköt ovat Hollolassa toimiva Oilon Home Oy ja Lahden pääkonttorissa toimiva Oilon Industry Oy. Yhdistämisellä haetaan säästöjä tuotantoyksiköiden välisistä logistiikkakuluista sekä kiinteistön vuokra- ja ylläpitokuluista ja samalla tehostetaan tehtaan sisäistä materiaalinkäsittelyä. Oilon Oy on toiminut Lahden pääkonttorissa jo yli 50 vuoden ajan ja sen tuotanto on kokenut historiansa aikana useita pienempiä muutoksia, jotka ovat jättäneet nykyiseen layoutiin paljon toivomisenvaraa. Jotta molemmat tuotantoyksiköt saadaan mahtumaan Lahden yksikköön, on sinne saatava luotua tarvittavat tilat siellä olemassa oleville toiminnoille ja Hollolan yksiköstä saapuville tuotantolinjoille. Työn alussa perehdytään kirjallisuuden avulla siihen kuinka tuotanto on kehittynyt maailmalla lähihistorian aikana, jotta voidaan paremmin ymmärtää Oilon Oy:n nykytilanteeseen johtaneita syitä. Koska Hollolasta saapuville tuotantolinjoille ei ole tarkoitus rakentaa uutta tuotantotilaa, pyritään tilaa vapauttamaan Lahden tehtaalta varastointia tehostamalla ja sen logistiikkaa helpottamalla. Tämän vuoksi vertaillaan yleisimpiä tavaroiden varastointi ratkaisuita sekä tutkitaan kuinka materiaalin käsittelyä voitaisiin tehostaa varastossa ja tuotantosuluissa. Varastoinnin tehostaminen ei kuitenkaan yksin riitä vapauttamaan tarvittavia tiloja, joten layout-muutoksen aikana rakennetaan myös kaksi uuttaa varastohallia. Uudessa layout-suunnitelmassa huomioidaan kunkin solun nykyiset ja tulevat tilantarpeet, sekä rakennetaan ne niin, että työvoimaa voidaan käyttää niissä joustavasti eri tuotteiden valmistamiseen. Tutkimusmetodeina käytetään teemahaastatteluita, joilla selvitetään työntekijöiden tarpeet sekä kirjallisuuden avulla perehdytään Lean-tuotantoon, kanban:iin, 5S:ään ja arvovirta-analyysiin. Näitä soveltamalla saadaan luotua tehokkaasti toimiva kokonaisuus, jolla tavoitellut säästöt saadaan toteutumaan.

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