Supply chain costs of a small board lot: sheet cutting and logistics

Succeeding in small board lot (0-20 tons) deliveries, is not always prosperous and failures as well as extra costs compared to standard costs arise. Failure deliveries from converting plants to customer locations tie a lot of unwanted and unexpected costs. Extra costs are handled as quality costs and more precise, internal failure costs. These costs revolve from unsuccessful truck payloads, redundant warehousing or unfavorable routing as examples. Quality costs are becoming more and more important factor in company’s financial decision making. Actual, realized truck payload correlates with the extra costs occurring, so filling the truck payload all get-out well is a key to lower the extra costs. Case company in this study is Corporation A, business segment Boards. Boards have outsourced half of their converting in order to gain better customer service via flexibility, lead time reductions and logistics efficiency improvements. Examination period of the study is first two quarters of year 2008 and deliveries examined are from converters to the customer locations. In Corporation A’s case, the total loss in failure deliveries is hundreds of thousands of Euros during the examination period. So, the logistics goal of getting the right product to the right place and right time for the least cost, does not completely realize.

Reducing Manufacturing Costs of the Screen Dryer’s Hot Section by Design

In this thesis, the purpose was to find the cost distribution of the screen dryer and the largest cost factors. The hot section of the screen dryer was revealed as the biggest cost factor, so composing new cost efficient solutions were directed to it. DFMA (Design for Manufacture and Assembly) was chosen to help the design process. DFMA is a product design strategy developed for taking manufacturing and assembly costs into account at the early stages of the design process. In the theory part of the thesis, other methods of economical design and tools needed for estimating manufacturing costs are introduced. In the empirical part, the hot section of the screen dryer was divided into sub-assemblies and their manufacturing costs were estimated. The design propositions were directed to the self-manufactured assemblies and parts. The new manufacturing costs were calculated for the developed propositions. Lastly, the most cost efficient solutions were summarized. The savings on the self-manufactured assemblies were about 40 %, which was about 13 % of the combined total costs of the hot section.

Dental Health in Primary Teeth after Prevention of Mother-Child Transmission of Mutans Streptococci. A Historical Cohort Study on Restorative Visits and Maternal Prevention Costs

Mutansstreptokokkitartunnan ehkäisemisen pitkäaikaisvaikutukset maitohampaiden terveyteen. Kohorttitutkimus korjaavan hoidon määrästä ja kariesehkäisyn kustannuksista. Tutkimuksen tarkoituksena oli selvittää varhaisen mutansstreptokokki (MS)-kolonisaation ehkäisyn pitkäaikaisvaikutuksia korkean kariesriskin omaavien lasten maitohampaistossa sekä tarkastella MS-tartunnan estämisen kustannuksia. Tiedot lasten hampaiden terveydestä ja hammashoitotoimenpiteistä syntymästä 10-vuotiaaksi sekä äiteihin kohdistuneen kariesehkäisyn kustannuksista kerättiin Ylivieskan terveyskeskuksen asiakirjoista. Tutkimuksessa oli mukana yhteensä 507 lasta, heistä 148 oli osallistunut aikaisempaan Ylivieskan äiti-lapsitutkimukseen, jossa verrattiin äitien käyttämän ksylitolipurukumin ja äidille tehtyjen fluori- tai klooriheksidiinilakkausten vaikutusta pikkulasten hampaiden terveyteen. Maitohammaskariesta esiintyi 10-vuotiaaksi asti merkitsevästi vähemmän lapsilla, jotka eivät olleet saaneet MS-tartuntaa alle 2-vuotiaana, heidän maitohampaansa säilyivät 3,4 vuotta kauemmin täysin ehjinä (p<0.001) ja he tarvitsivat vähemmän maitohampaiden korjaavaa hoitoa (p=0.005) kuin lapset, joiden hampaisto oli kolonisoitunut MS-bakteerilla jo 2-vuotiaana. Koska ksylitoliryhmän lasten MS-kolonisaatio oli vähäisintä, heidän maitohampaissaan oli vähemmän kariesta ja korjaavan hoidon tarvetta kuin kahden muun korkeariskisen ryhmän lapsilla. Äitien käyttämän ksylitolipurukumin kustannukset olivat yhteensä 116 euroa ja lapsen maitohampaiden säilyminen täysin ehjinä vuoden pidempään maksoi 37 euroa. Kun MS-tartunta oli saatu estettyä, korkean kariesriskin omaavien lasten hampaiden terveys oli samalla tasolla kuin keskimäärin koko ikäkohortilla. Lapsen maitohampaat säilyvät terveinä pidempään ja korjaavan hoidon tarve vähenee, kun MS-kolonisaatio alle 2-vuotiaana saadaan estettyä. Lapsen MS-kolonisaatio vähenee merkitsevästi, kun äiti käyttää ksylitolipurukumia lapsen ollessa 0-2 vuoden ikäinen, siten pikkulapsen äidin säännöllinen ksylitolipurukumin käyttö saattaa olla julkisen tereydenhuollon kannalta tarkoituksenmukainenterveyttä edistävä menetelmä.

Delivery, Outcome, and Costs of Orthodontic Care in Finnish Health Centres

The goal of the study was to analyse orthodontic care in Finnish health centres with special reference to the delivery, outcome and costs of treatment. Public orthodontic care was studied by two questionnaires sent to the chief dental officers of all health centres (n = 276) and to all specialist orthodontists in Finland (n = 146). The large regional variation was mentioned by the orthodontists as the most important factor requiring improvement. Orthodontic practices and outcome were studied in eight Finnish municipal health centres representing early and late timing of treatment. A random sample of 16- and 18-year-olds (n = 1109) living in these municipalities was examined for acceptability of occlusion with the Occlusal Morphology and Function Index (OMFI). In acceptability of occlusion, only minor differences were found between the two timing groups. The percentage of subjects with acceptable morphology was higher among untreated than among treated adolescents. The costs of orthodontic care were estimated among the adolescents with a treatment history. The mean appliance costs were higher in the late, and the mean visit costs higher in the early timing group. The cost-effectiveness of orthodontic services differed among the health centres, but was almost equal in the two timing groups. National guidelines and delegation of orthodontic tasks were suggested as the tools for reducing the variation among the health centres. In the eight health centres, considerable variation was found in acceptability of occlusion and in cost-effectiveness of services. The cost-effectiveness was not directly connected with the timing of treatment.

Monitoring of centrifugal pump operation by a frequency converter

Centrifugal pumps are widely used in industrial and municipal applications, and they are an important end-use application of electric energy. However, in many cases centrifugal pumps operate with a significantly lower energy efficiency than they actually could, which typically has an increasing effect on the pump energy consumption and the resulting energy costs. Typical reasons for this are the incorrect dimensioning of the pumping system components and inefficiency of the applied pump control method. Besides the increase in energy costs, an inefficient operation may increase the risk of a pump failure and thereby the maintenance costs. In the worst case, a pump failure may lead to a process shutdown accruing additional costs. Nowadays, centrifugal pumps are often controlled by adjusting their rotational speed, which affects the resulting flow rate and output pressure of the pumped fluid. Typically, the speed control is realised with a frequency converter that allows the control of the rotational speed of an induction motor. Since a frequency converter can estimate the motor rotational speed and shaft torque without external measurement sensors on the motor shaft, it also allows the development and use of sensorless methods for the estimation of the pump operation. Still today, the monitoring of pump operation is based on additional measurements and visual check-ups, which may not be applicable to determine the energy efficiency of the pump operation. This doctoral thesis concentrates on the methods that allow the use of a frequency converter as a monitoring and analysis device for a centrifugal pump. Firstly, the determination of energy-efficiency- and reliability-based limits for the recommendable operating region of a variable-speed-driven centrifugal pump is discussed with a case study for the laboratory pumping system. Then, three model-based estimation methods for the pump operating location are studied, and their accuracy is determined by laboratory tests. In addition, a novel method to detect the occurrence of cavitation or flow recirculation in a centrifugal pump by a frequency converter is introduced. Its sensitivity compared with known cavitation detection methods is evaluated, and its applicability is verified by laboratory measurements for three different pumps and by using two different frequency converters. The main focus of this thesis is on the radial flow end-suction centrifugal pumps, but the studied methods can also be feasible with mixed and axial flow centrifugal pumps, if allowed by their characteristics.

Costs and Benefits of a Shared Digital Long-Term Preservation System

Paper presented at the 40th Annual Conference of LIBER (Ligue des Bibliothèques Européennes de Recherche - Association of European Research Libraries) on July 1st, 2011; with the slides used at the presentation.

Toikansuon kaatopaikkakaasun hyödyntäminen kaukolämmöntuotantoon

Tämän työn päätavoitteena oli selvittää, onko Toikansuon kaatopaikkakaasun hyödyntäminen kaukolämmöntuotantoon Lappeenrannan Energialle taloudellisesti kannattavaa. Kaatopaikkakaasulla voitaisiin korvata kaukolämmöntuotannossa puuta ja maakaasua, mistä aiheutuisi säästöä. Kaukolämmöntuotantoa varten olisi hankittava lämpökeskus ja rakennettava tarvittava infrastruktuuri, mistä aiheutuisi taas toisaalta kustannuksia. Paroc hyödyntää nykyisin Toikansuon kaatopaikkakaasun. Paroc ei hyödynnä kaasua niin paljon kuin olisi mahdollista, ja tulevaisuudessa Paroc ei välttämättä pysty hyödyntämään kaasua ollenkaan. Työssä arvioitiin Toikansuon kaatopaikkakaasupotentiaali, jonka perusteella pyydettiin toimittajilta tarjous kohteeseen soveltuvasta lämpökeskuksesta. Lämpökeskukselle etsittiin lisäksi sijoituspaikka sekä arvioitiin tarvittavan infrastruktuurin rakentamisesta aiheutuvat kustannukset ja lämpökeskuksen käytönaikaiset kustannukset. Aiheutuvia kustannuksia verrattiin vaihtoehtoisten kaukolämmöntuotantotapojen polttoainekustannuksissa saavutettuun säästöön nykyarvomenetelmän avulla. Investoinnin nykyarvo esitettiin eri kaatopaikkakaasun hinnoilla, sillä kaatopaikkakaasusta maksettava hinta on Lappeenrannan Energian ja Lappeenrannan kaupungin välinen neuvottelukysymys. Työn tulosten perusteella Toikansuon kaatopaikkakaasua pystyttäisiin hyödyntämään kaukolämmöntuotantoon noin 15 vuotta. Investointi on Lappeenrannan Energialle kannattava, kunhan kaatopaikkakaasusta maksettava hinta on riittävän alhainen ja laskelmiin valitut lähtöarvot pitävät riittävän hyvin paikkansa. Investointiin sisältyy kuitenkin riskinsä, sillä laskelmat sisältävät useita tulevaisuudessa muuttuvia tekijöitä, joiden kehitystä on vaikea arvioida tarkasti. Investointia tulisi harkita, jos Paroc ei pysty tulevaisuudessa hyödyntämään kaasua ollenkaan tai tavoitteena on minimoida kasvihuonekaasupäästöt. Pelkkää taloudellisen tuoton tavoittelua ajatellen investointi on liian epävarma.

Costs and Benefits of a Shared Digital Long-Term Preservation System

This paper describes the cost-benefit analysis of digital long-term preservation (LTP) that was carried out in the context of the Finnish National Digital Library Project (NDL) in 2010. The analysis was based on the assumption that as many as 200 archives, libraries, and museums will share an LTP system. The term ‘system’ shall be understood as encompassing not only information technology, but also human resources, organizational structures, policies and funding mechanisms. The cost analysis shows that an LTP system will incur, over the first 12 years, cumulative costs of €42 million, i.e. an average of €3.5 million per annum. Human resources and investments in information technology are the major cost factors. After the initial stages, the analysis predicts annual costs of circa €4 million. The analysis compared scenarios with and without a shared LTP system. The results indicate that a shared system will have remarkable benefits. At the development and implementation stages, a shared system shows an advantage of €30 million against the alternative scenario consisting of five independent LTP solutions. During the later stages, the advantage is estimated at €10 million per annum. The cumulative cost benefit over the first 12 years would amount to circa €100 million.

Non-Markovian Dynamics in Continuous Variable Quantum Systems

The present manuscript represents the completion of a research path carried forward during my doctoral studies in the University of Turku. It contains information regarding my scientific contribution to the field of open quantum systems, accomplished in collaboration with other scientists. The main subject investigated in the thesis is the non-Markovian dynamics of open quantum systems with focus on continuous variable quantum channels, e.g. quantum Brownian motion models. Non-Markovianity is here interpreted as a manifestation of the existence of a flow of information exchanged by the system and environment during the dynamical evolution. While in Markovian systems the flow is unidirectional, i.e. from the system to the environment, in non-Markovian systems there are time windows in which the flow is reversed and the quantum state of the system may regain coherence and correlations previously lost. Signatures of a non-Markovian behavior have been studied in connection with the dynamics of quantum correlations like entanglement or quantum discord. Moreover, in the attempt to recognisee non-Markovianity as a resource for quantum technologies, it is proposed, for the first time, to consider its effects in practical quantum key distribution protocols. It has been proven that security of coherent state protocols can be enhanced using non-Markovian properties of the transmission channels. The thesis is divided in two parts: in the first part I introduce the reader to the world of continuous variable open quantum systems and non-Markovian dynamics. The second part instead consists of a collection of five publications inherent to the topic.

Modeling and simulation of forced-air cooling of strawberries using variable convective coefficient

In the forced-air cooling process of fruits occurs, besides the convective heat transfer, the mass transfer by evaporation. The energy need in the evaporation is taken from fruit that has its temperature lowered. In this study it has been proposed the use of empirical correlations for calculating the convective heat transfer coefficient as a function of surface temperature of the strawberry during the cooling process. The aim of this variation of the convective coefficient is to compensate the effect of evaporation in the heat transfer process. Linear and exponential correlations are tested, both with two adjustable parameters. The simulations are performed using experimental conditions reported in the literature for the cooling of strawberries. The results confirm the suitability of the proposed methodology.

Fuzzy rule-based system for evaluation of uncertainty transaction in cassava chain

A fuzzy ruled-based system was developed in this study and resulted in an index indicating the level of uncertainty related to commercial transactions between cassava growers and their dealers. The fuzzy system was developed based on Transaction Cost Economics approach. The fuzzy system was developed from input variables regarding information sharing between grower and dealer on “Demand/purchase Forecasting”, “Production Forecasting” and “Production Innovation”. The output variable is the level of uncertainty regarding the transaction between seller and buyer agent, which may serve as a system for detecting inefficiencies. Evidences from 27 cassava growers registered in the Regional Development Offices of Tupa and Assis, São Paulo, Brazil, and 48 of their dealers supported the development of the system. The mathematical model indicated that 55% of the growers present a Very High level of uncertainty, 33% present Medium or High. The others present Low or Very Low level of uncertainty. From the model, simulations of external interferences can be implemented in order to improve the degree of uncertainty and, thus, lower transaction costs.

Effects of a Financial Transaction Tax - Do Transaction Costs Lower Volatility?: A Literature Review

In this literature review the theorethical framework of Financial transaction taxes and their assumed effect on market volatility is assessed. The empirical evidence from various studies is compared against the theory and a simple empirical review of the Finnish stock market is conducted. The findings implicate that financial transaction taxes can not reduce volatility and their actual effect on markets is dependend by many other factors as well. Some evidence even suggests that transactions taxes may actually raise volatility.

Variable structure position control of an industrial robotic manipulator

The use of a robust position controller for a robotic manipulator moving in free space is presented. The aim is to implement in practice a controller that is robust to uncertainties in the model of the system, as well as being inexpensive from a computational point of view. Variable structure theory provides the technique for the design of such controller. The design steps are presented, first from a theoretical perspective and then applied to the control of a two degree-of-freedom manipulator. Simulation results that backed the implementation are presented, followed by the experiments conducted and the results that were obtained. The conclusion is that variable structure control is readily applicable to industrial robots for the robust control of positions.