This thesis reports a new set of experimental data and presents an in-depth analysis of the flow physics of a jet stream produced by a large quarter-round corner-mounted displacement diffuser. The air velocity, temperature and turbulence intensity inside the displacement ventilation (DV) jet have been thoroughly analyzed and compared with the reported findings of previous studies and model predictions. Furthermore, thermal comfort has been analyzed using the measured data following the ASHRAE standard. This thesis also aims at establishing an accurate numerical approach for simulating the heat and fluid flow in a room ventilated by a DV system. The supply boundary condition has been thoroughly investigated, which includes tests of the conventional box and momentum modeling methods, and proposal of a more accurate modeling approach. In addition, the predictive accuracy of the standard k-ϵ, RNG k-ϵ, SST k-ω and RSM turbulence models has been examined against the experimental data.

We study the supervisory control of supply chain operation modelled by (timed) State Tree Structures (STS). We model each agent involved in a supply chain using holons. Three operational models, make-to-order, make-to-stock, and assemble-to-order are considered. A strong assumption on the original STS theory is weakened to allow events shared among agents to be located at different levels. A supervisor is synthesized for the example of a mattress supply chain with make-to-stock operation under certain specifications. Moreover, a new version of the Timed STS framework is developed to allow events to have an upper time bound i.e. deadline. With Timed STS framework, more specifications requiring time measurement can be modeled and a supervisory control is synthesized for the timed model of a supply chain. For a nonempty supervisory synthesis result, the maximum time for the inventory periodic review rate, and the minimum cycle time for customer order satisfaction are achieved.

We study the supervisory control of supply chain operation modelled by (timed) State Tree Structures (STS). We model each agent involved in a supply chain using holons. Three operational models, make-to-order, make-to-stock, and assemble-to-order are considered. A strong assumption on the original STS theory is weakened to allow events shared among agents to be located at different levels. A supervisor is synthesized for the example of a mattress supply chain with make-to-stock operation under certain specifications. Moreover, a new version of the Timed STS framework is developed to allow events to have an upper time bound i.e. deadline. With Timed STS framework, more specifications requiring time measurement can be modeled and a supervisory control is synthesized for the timed model of a supply chain. For a nonempty supervisory synthesis result, the maximum time for the inventory periodic review rate, and the minimum cycle time for customer order satisfaction are achieved.

The purpose of this thesis is to point out how a company can gain a better process by using PM in an effective way. The report concludes that the existence in practice of theoretically important aspects are different, also that the most correct way of leading the aspects are through the creation of a PM process. During this thesis work the benefits with performance measurements have been analyzed. Since the genesis of the industrialisation there have been growing needs to identify ways of understanding how a company functions. One of the main events historically leading to the broad adoption of PM was the introduction of the DuPont model. The DuPont model developed by DuPont and General Motors during the beginning of the 20th century quickly became the industry standard in the US for financial analysis. The Dupont model gave PM a central role in evaluating the performance of a company. Companies are today driven towards a higher level of responsiveness and flexibility in order to remain competitive. In order to measure the advancement towards these objectives, an increasingly complex set of activities collection of PM to monitor performance satisfactorily. Often however, PM are still developed around traditional, functional metrics focusing on departmental issues, rather than on the whole value stream. There has also been analyzed how a manufacturing company can use PM in an effective way. Under this thesis it emerged that the most crucial factor affecting the companies PM was that it was hard to understand how to use it correctly. When a company use it correctly it determines where the company stands, if they want to be competitive in the future and a method to maintain a good value stream flow. The economical factors for the company are at least important because all decisions always include costly investments. At the same time a company’s PM must be as efficient as possible and generate a good investment. Also other factors have been presented in this thesis but do not affect the effectiveness of the PM. The most important factors found to a more effective PM were; does the PM fulfil its purpose, is the performance attained, to make the purpose explicit and at last boost the education around the subject. The whole research has been carried out over a twenty-week period, during that period data collection has been performed via case studies. The rest of the data collection has been collected through a literature review by examining relevant data to answer the two research questions. This thesis have led to a better understanding regarding how to use PM and the benefits of it. This are based on the collected data from the case studies and from the theoretical findings, the empirical data were analyzed in a way that the company understood what was wrong with today´s PM.

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The purpose of this dissertation is to provide an effective approach to design the supply chain (SC) of the cellulosic biofuel industry in order that it will support and accelerate the successful commercialization of the cellulosic biofuel industry. The methods of approach to this problem are (1) to assess the state-of-the-art biofuel SC studies, (2) to provide a decision support tool based on a mixed integer programming (MIP) model for the cellulosic biofuel supply chain design problem (BSCP), (3) to devise an exact solution method to solve large-scale instances of BSCP, (4) to evaluate a biomass logistics system based on biomass modules, by using new simulation elements for new machines, and (5) to compare several biomass logistics systems based on biomass module, bale, and silage, using simulation models. The first part of this dissertation broadly reviews the literature on biofuel SCs, analyzing the state-of-the-art biofuel and petroleum-based fuel SC studies as well as relating generic SC models that have been published over the last decade to the biofuel SC (An et al., 2010a). The resulting analysis proposes fertile opportunity for future research to contribute to improving biofuel SC. The second part of this dissertation formulates BSCP as a MIP model, which is a time-staged, multi-commodity flow, network design problem with an objective of maximizing profit (An et al., 2010b). The model prescribes strategic level decisions (i.e., facility locations, capacities, and technology types) as well as plans for transportation routes and material flows (i.e., quantities produced, stored, and transported) in each time period. A case study demonstrates managerial use in application to a region in Central Texas. The third part of this dissertation provides an exact solution method to solve BSCP. An embedded structure can be transformed to a generalized minimum cost flow problem, which is used as a sub-problem in a CG approach. This study proposes a dynamic programming algorithm to solve the sub-problem in O(m), generating improving path-flows. To accelerate branch-and-bound (B&B) search, it develops an inequality, called the partial objective constraint (POC), which is based on the portion of the objective function associated with binary variables. The fourth part of this dissertation evaluates a biomass module system, which is a conceptual logistics system based on large packages of chopped biomass with sufficient size and density to provide maximized legal highway loads and quick load/unload times. The last part of this dissertation evaluates economic benefits of the biomass module system, comparing it to bale and silage systems.

Ring oscillators provide a central role in timing circuits for today?s mobile devices and desktop computers. Increased integration in these devices exacerbates switching noise on the supply, necessitating improved supply resilience. Furthermore, reduced voltage headroom in submicron technologies limits the number of stacked transistors available in a delay cell. Hence, conventional single-loop oscillators offer relatively few design options to achieve desired specifications, such as supply rejection. Existing state-of-the-art supply-rejection- enhancement methods include actively regulating the supply with an LDO, employing a fully differential or current-starved delay cell, using a hi-Z voltage-to-current converter, or compensating/calibrating the delay cell. Multiloop ring oscillators (MROs) offer an additional solution because by employing a more complex ring-connection structure and associated delay cell, the designer obtains an additional degree of freedom to meet the desired specifications. Designing these more complex multiloop structures to start reliably and achieve the desired performance requires a systematic analysis procedure, which we attack on two fronts: (1) a generalized delay-cell viewpoint of the MRO structure to assist in both analysis and circuit layout, and (2) a survey of phase-noise analysis to provide a bank of methods to analyze MRO phase noise. We distill the salient phase-noise-analysis concepts/key equations previously developed to facilitate MRO and other non-conventional oscillator analysis. Furthermore, our proposed analysis framework demonstrates that all these methods boil down to obtaining three things: (1) noise modulation function (NMF), (2) noise transfer function (NTF), and (3) current-controlled-oscillator gain (KICO). As a case study, we detail the design, analysis, and measurement of a proposed multiloop ring oscillator structure that provides improved power-supply isolation (more than 20dB increase in supply rejection over a conventional-oscillator control case fabricated on the same test chip). Applying our general multi-loop-oscillator framework to this proposed MRO circuit leads both to design-oriented expressions for the oscillation frequency and supply rejection as well as to an efficient layout technique facilitating cross-coupling for improved quadrature accuracy and systematic, substantially simplified layout effort.

This master final paper formulates pricing of water sector services, analyzes sustainable price for water services, evaluates tax rates, paid for water, from every water user. The purpose of this paper is to find out reasons, which are damaging for JSC “Šiaulių vandenys” future efficiency and viability. It analyzes and systemizes theoretical and practical research from scientific, methodological and publicist literature, along with special research water methods. The hypothesis of this master paper was substantiated only partly, because an efficiently water pricing depends not only from water service company, but from political, legal and environmental frames as well, which come directly from the State government and EU directives.

Network relationships play a significant role in the provision of servitized offerings. To date, little empirical research has been conducted to investigate the link between servitization and inter-organisational relationships. The objective of this doctoral thesis is to explore the implications of servitization on a manufacturer’s network. Particular emphasis is placed on the impact on the network structure and relationship attributes. An exploratory in-depth case study was conducted within the truck manufacturing industry using a multi-organisational perspective. An abductive research approach was adopted which was underlined by pragmatism. As part of this approach, 43 interviews were conducted in a total of 11 companies. The findings of the study suggest that managers need to be aware of the different customer needs, related offerings and resultant implications on the network structure and relationships. To this end, the findings show that as the offerings move towards advanced servitized offerings the network becomes more complex in terms of its structure and relationships. The research contributes to the literature by providing a more nuanced description of what actually occurs in a network when a manufacturer provides servitized offerings in conjunction with other product-based offerings. In particular, it identifies the relationship attributes that need to be managed in order to drive the right behaviour for the provision of each of these offerings. Moreover, it is the first known study to uncover triadic as well as tetradic network structures in a servitization context. Equally important, it provides a framework that captures the interplay between the different offerings and the resultant network structure and relationship attributes. In all of these capacities, this research is one of the first known studies to uncover some of the complexities surrounding the way in which inter-organisational relationships are enacted in a servitization context.