908 resultados para Machine-tools
Resumo:
Prostate-specific antigen (PSA) is a marker that is commonly used in estimating prostate cancer risk. Prostate cancer is usually a slowly progressing disease, which might not cause any symptoms whatsoever. Nevertheless, some cases of cancer are aggressive and need to be treated before they become life-threatening. However, the blood PSA concentration may rise also in benign prostate diseases and using a single total PSA (tPSA) measurement to guide the decision on further examinations leads to many unnecessary biopsies, over-detection, and overtreatment of indolent cancers which would not require treatment. Therefore, there is a need for markers that would better separate cancer from benign disorders, and would also predict cancer aggressiveness. The aim of this study was to evaluate whether intact and nicked forms of free PSA (fPSA-I and fPSA-N) or human kallikrein-related peptidase 2 (hK2) could serve as new tools in estimating prostate cancer risk. First, the immunoassays for fPSA-I and free and total hK2 were optimized so that they would be less prone to assay interference caused by interfering factors present in some blood samples. The optimized assays were shown to work well and were used to study the marker concentrations in the clinical sample panels. The marker levels were measured from preoperative blood samples of prostate cancer patients scheduled for radical prostatectomy. The association of the markers with the cancer stage and grade was studied. It was found that among all tested markers and their combinations especially the ratio of fPSA-N to tPSA and ratio of free PSA (fPSA) to tPSA were associated with both cancer stage and grade. They might be useful in predicting the cancer aggressiveness, but further follow-up studies are necessary to fully evaluate the significance of the markers in this clinical setting. The markers tPSA, fPSA, fPSA-I and hK2 were combined in a statistical model which was previously shown to be able to reduce unnecessary biopsies when applied to large screening cohorts of men with elevated tPSA. The discriminative accuracy of this model was compared to models based on established clinical predictors in reference to biopsy outcome. The kallikrein model and the calculated fPSA-N concentrations (fPSA minus fPSA-I) correlated with the prostate volume and the model, when compared to the clinical models, predicted prostate cancer in biopsy equally well. Hence, the measurement of kallikreins in a blood sample could be used to replace the volume measurement which is time-consuming, needs instrumentation and skilled personnel and is an uncomfortable procedure. Overall, the model could simplify the estimation of prostate cancer risk. Finally, as the fPSA-N seems to be an interesting new marker, a direct immunoassay for measuring fPSA-N concentrations was developed. The analytical performance was acceptable, but the rather complicated assay protocol needs to be improved until it can be used for measuring large sample panels.
Resumo:
In the Innovation Union Scoreboard of 2011, Latvia ranked last amongst the EU countries in innovation performance. Even though there is sufficient scientific and technological basis, the results remain modest or low in most of the indicators concerning innovations. Several aspects influence the performance a national innovation system. In Latvia, the low effectiveness is often attributed to lack of financial support tools. As a comparison, Finland was chosen because of its well-established and documented innovation system. The aim of this study is to research the efficiency and effectiveness of the current financial innovation support tool system in Latvia from the point of view of an innovating company. It also attempts to analyze the support tool system of Latvia and compare to the relevant parts of the Finnish system. The study found that it is problematic for innovative companies in Latvia to receive the necessary funding especially for start-ups and SMEs due to the low number of grant programs, funds and lacking offer from banks, venture capital and business angels. To improve the situation, the Latvian government should restructure the funding mechanisms putting a bigger emphasis on innovative start-ups and SMEs. That would lay a foundation for future growth and boost research and scientific activities in Latvia.
Resumo:
This bachelor’s thesis is a part of the research project realized in the summer 2011 in Lappeenranta University of Technology. The goal of the project was to develop an automation concept for controlling the externally excited synchronous motor. Thesis concentrates on the testing planning and testing the system. Testing plan was made for three sectors: For the PLC program testing, for the communication testing and for the whole system testing. PLC program was tested with white box and destructive methods. Communication testing was done by switching maximum com-munication speed and checked if communication was reliable. Whole system testing included among other things speed and torque controlling. The system was tested with exploratory testing also. This enabled more reliable and broader testing than with systematical testing only.
Resumo:
This master’s thesis mainly focuses on the design requirements of an Electric drive for Hybrid car application and its control strategy to achieve a wide speed range. It also emphasises how the control and performance requirements are transformed into its design variables. A parallel hybrid topology is considered where an IC engine and an electric drive share a common crank shaft. A permanent magnet synchronous machine (PMSM) is used as an electric drive machine. Performance requirements are converted into Machine design variables using the vector model of PMSM. Main dimensions of the machine are arrived using analytical approach and Finite Element Analysis (FEA) is used to verify the design and performance. Vector control algorithm was used to control the machine. The control algorithm was tested in a low power PMSM using an embedded controller. A prototype of 10 kW PMSM was built according to the design values. The prototype was tested in the laboratory using a high power converter. Tests were carried out to verify different operating modes. The results were in agreement with the calculations.
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The current research emphasizes on various questions raised and deliberated upon by different entrepreneurs. It provides a valuable contribution to comprehend the importance of social media and ICT-applications. Furthermore, it demonstrates how to support and implement the management consulting and business coaching start-ups with the help of social media and ICT-tools. The thesis presents a literary review from different information systems science, SME and e-business journals, web articles, as well as, survey analysis reports on social media applications. The methodology incorporated into a qualitative research method in which social anthropological approaches were used to oversee the case study activities in order to collect data. The collaborative social research approach was used to shelter the action research method. The research discovered that new business start-ups, as well as small businesses do not use social media and ICT-tools, unlike most of the large corporations use. At present, the current open-source ICT-technologies and social media applications are equally available for new and small businesses as they are available for larger companies. Successful implementation of social media and ICT-applications can easily enhance start-up performance and overcome business hassles. The thesis sheds some light on effective and innovative implementation of social media and ICT-applications for new business risk takers and small business birds. Key words
Resumo:
Technological developments in microprocessors and ICT landscape have made a shift to a new era where computing power is embedded in numerous small distributed objects and devices in our everyday lives. These small computing devices are ne-tuned to perform a particular task and are increasingly reaching our society at every level. For example, home appliances such as programmable washing machines, microwave ovens etc., employ several sensors to improve performance and convenience. Similarly, cars have on-board computers that use information from many di erent sensors to control things such as fuel injectors, spark plug etc., to perform their tasks e ciently. These individual devices make life easy by helping in taking decisions and removing the burden from their users. All these objects and devices obtain some piece of information about the physical environment. Each of these devices is an island with no proper connectivity and information sharing between each other. Sharing of information between these heterogeneous devices could enable a whole new universe of innovative and intelligent applications. The information sharing between the devices is a diffcult task due to the heterogeneity and interoperability of devices. Smart Space vision is to overcome these issues of heterogeneity and interoperability so that the devices can understand each other and utilize services of each other by information sharing. This enables innovative local mashup applications based on shared data between heterogeneous devices. Smart homes are one such example of Smart Spaces which facilitate to bring the health care system to the patient, by intelligent interconnection of resources and their collective behavior, as opposed to bringing the patient into the health system. In addition, the use of mobile handheld devices has risen at a tremendous rate during the last few years and they have become an essential part of everyday life. Mobile phones o er a wide range of different services to their users including text and multimedia messages, Internet, audio, video, email applications and most recently TV services. The interactive TV provides a variety of applications for the viewers. The combination of interactive TV and the Smart Spaces could give innovative applications that are personalized, context-aware, ubiquitous and intelligent by enabling heterogeneous systems to collaborate each other by sharing information between them. There are many challenges in designing the frameworks and application development tools for rapid and easy development of these applications. The research work presented in this thesis addresses these issues. The original publications presented in the second part of this thesis propose architectures and methodologies for interactive and context-aware applications, and tools for the development of these applications. We demonstrated the suitability of our ontology-driven application development tools and rule basedapproach for the development of dynamic, context-aware ubiquitous iTV applications.
Resumo:
Measurement is a tool for researching. Therefore, it is important that the measuring process is carried out correctly, without distorting the signal or the measured event. Researches of thermoelectric phenomena have been focused more on transverse thermoelectric phenomena during recent decades. Transverse Seebeck effect enables to produce thinner and faster heat flux sensor than before. Studies about transverse Seebeck effect have so far focused on materials, so in this Master’s Thesis instrumentation of transverse Seebeck effect based heat flux sensor is studied, This Master’s Thesis examines an equivalent circuit of transverse Seebeck effect heat flux sensors, their connectivity to electronics and choosing and design a right type amplifier. The research is carried out with a case study which is Gradient Heat Flux Sensors and an electrical motor. In this work, a general equivalent circuit was presented for the transverse Seebeck effect-based heat flux sensor. An amplifier was designed for the sensor of the case study, and the solution was produced for the measurement of the local heat flux of the electric motor to improve the electromagnetic compatibility.
Resumo:
The power demand of many mobile working machines such as mine loaders, straddle carriers and harvesters varies significantly during operation, and typically, the average power demand of a working machine is considerably lower than the demand for maximum power. Consequently, for most of the time, the diesel engine of a working machine operates at a poor efficiency far from its optimum efficiency range. However, the energy efficiency of dieseldriven working machines can be improved by electric hybridization. This way, the diesel engine can be dimensioned to operate within its optimum efficiency range, and the electric drive with its energy storages responds to changes in machine loading. A hybrid working machine can be implemented in many ways either as a parallel hybrid, a series hybrid or a combination of these two. The energy efficiency of hybrid working machines can be further enhanced by energy recovery and reuse. This doctoral thesis introduces the component models required in the simulation model of a working machine. Component efficiency maps are applied to the modelling; the efficiency maps for electrical machines are determined analytically in the whole torque–rotational speed plane based on the electricalmachine parameters. Furthermore, the thesis provides simulation models for parallel, series and parallel-series hybrid working machines. With these simulation models, the energy consumption of the working machine can be analysed. In addition, the hybridization process is introduced and described. The thesis provides a case example of the hybridization and dimensioning process of a working machine, starting from the work cycle of the machine. The selection and dimensioning of the hybrid system have a significant impact on the energy consumption of a hybrid working machine. The thesis compares the energy consumption of a working machine implemented by three different hybrid systems (parallel, series and parallel-series) and with different component dimensions. The payback time of a hybrid working machine and the energy storage lifetime are also estimated in the study.
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The Japanese quail Coturnix japonica originated from North Africa, Europe and Asia, is used worldwide as an experimental animal and model for aviculture. The current paper characterizes Eimeria bateri, Eimeria tsunodai and Eimeria uzura recovered from C. japonica. Based on the fact that quails have a global distribution, as are their coccidia, the findings of this study should provide the means for diagnosis of those Eimeria spp. in other regions and continents. Eimeria bateri showed the greatest intensity of infection and shed oocysts from the fourth day after infection; in contrast, E. tsunodai and E. uzura shed oocysts from the fifth day after infection. The three species shared a high degree of similarity and were all polymorphic. Yet, the application of line regressions, histograms and ANOVA provided means for the identification of these species. Finally, the algorithm was very efficient since verified that resultant values were not superimposed.
Resumo:
Paremmin lastuttavia M-käsiteltyjä teräksiä on käytetty yrityksissä jo yli 20 vuoden ajan. Ominaisuuksiensa ansiosta M-teräksillä on pystytty pienentämään koneistuskustannuksia ja parantamaan kilpailukykyä. Viime vuosien aikana lastuavat terät ja työstökoneet ovat kuitenkin kehittyneet ja ero M-terästen ja tavanomaisten terästen välillä on voinut kaventua. Tämän diplomityön tavoitteena oli tutkia, saavutetaanko M-teräksen käytöllä taloudellisia etuja nykyaikaisissa konepajaolosuhteissa. Tutkimuksessa vertailtiin M-käsitellyn ja tavanomaisen 42CrMo4 – teräksen koneistusta. Valmistuskokeissa tarkasteltiin terien kulumista, lastun muotoa ja pinnanlaatua. Koekappaleena toimi olakkeellinen kuusiomutteri M64 kierteellä. Tuotteita valmistettiin yli 500 kappaletta ja materiaalia poistettiin noin 2000 kg. Koetulosten perusteella tuotteille laskettiin koneistuskustannukset kuvitteellisessa yrityksessä. Ero materiaalien välillä oli suurin työvaiheissa, joissa lastuaminen oli jatkuvaa. Sisä- ja ulkosorvauksessa M-käsiteltyä terästä lastunneiden terien kestoikä oli noin kaksinkertainen ja kierteen sorvauksessa noin nelinkertainen tavalliseen teräkseen verrattuna. Hakkaavassa työstössä terien kestoikä oli molemmilla materiaaleilla sama. Työssä suoritettujen kokeiden ja kustannuslaskelmien perusteella, käyttämällä M-käsiteltyä terästä voidaan pienentää valmistuskustannuksia. Materiaalien välinen ero korostuu, kun hakkaavaa työstöä on vähän, sarjat ovat suuria ja tuotanto on miehittämätöntä.
Resumo:
This doctoral thesis presents a study on the design of tooth-coil permanent magnet synchronous machines. The electromagnetic properties of concentrated non-overlapping winding permanent magnet synchronous machines, or simply tooth-coil permanent magnet synchronous machines (TC-PMSMs), are studied in details. It is shown that current linkage harmonics play the deterministic role in the behavior of this type of machines. Important contributions are presented as regards of calculation of parameters of TC-PMSMs,particularly the estimation of inductances. The current linkage harmonics essentially define the air-gap harmonic leakage inductance, rotor losses and localized temporal inductance variation. It is proven by FEM analysis that inductance variation caused by the local temporal harmonic saturation results in considerable torque ripple, and can influence on sensorless control capabilities. Example case studies an integrated application of TC-IPMSMs in hybrid off-highway working vehicles. A methodology for increasing the efficiency of working vehicles is introduced. It comprises several approaches – hybridization, working operations optimization, component optimization and integration. As a result of component optimization and integration, a novel integrated electro-hydraulic energy converter (IEHEC) for off-highway working vehicles is designed. The IEHEC can considerably increase the operational efficiency of a hybrid working vehicle. The energy converter consists of an axial-piston hydraulic machine and an integrated TCIPMSM being built on the same shaft. The compact assembly of the electrical and hydraulic machines enhances the ability to find applications for such a device in the mobile environment of working vehicles.Usage of hydraulic fluid, typically used in working actuators, enables direct-immersion oil cooling of designed electrical machine, and further increases the torque- and power- densities of the whole device.
Resumo:
Magaly Basconesin esitys Kirjastoverkkopäivillä 24.10.2013 Helsingissä.
Resumo:
Drug discovery is a continuous process where researchers are constantly trying to find new and better drugs for the treatment of various conditions. Alzheimer’s disease, a neurodegenerative disease mostly affecting the elderly, has a complex etiology with several possible drug targets. Some of these targets have been known for years while other new targets and theories have emerged more recently. Cholinesterase inhibitors are the major class of drugs currently used for the symptomatic treatment of Alzheimer’s disease. In the Alzheimer’s disease brain there is a deficit of acetylcholine and an impairment in signal transmission. Acetylcholinesterase has therefore been the main target as this is the main enzyme hydrolysing acetylcholine and ending neurotransmission. It is believed that by inhibiting acetylcholinesterase the cholinergic signalling can be enhanced and the cognitive symptoms that arise in Alzheimer’s disease can be improved. Butyrylcholinesterase, the second enzyme of the cholinesterase family, has more recently attracted interest among researchers. Its function is still not fully known, but it is believed to play a role in several diseases, one of them being Alzheimer’s disease. In this contribution the aim has primarily been to identify butyrylcholinesterase inhibitors to be used as drug molecules or molecular probes in the future. Both synthetic and natural compounds in diverse and targeted screening libraries have been used for this purpose. The active compounds have been further characterized regarding their potencies, cytotoxicity, and furthermore, in two of the publications, the inhibitors ability to also inhibit Aβ aggregation in an attempt to discover bifunctional compounds. Further, in silico methods were used to evaluate the binding position of the active compounds with the enzyme targets. Mostly to differentiate between the selectivity towards acetylcholinesterase and butyrylcholinesterase, but also to assess the structural features required for enzyme inhibition. We also evaluated the compounds, active and non-active, in chemical space using the web-based tool ChemGPS-NP to try and determine the relevant chemical space occupied by cholinesterase inhibitors. In this study, we have succeeded in finding potent butyrylcholinesterase inhibitors with a diverse set of structures, nine chemical classes in total. In addition, some of the compounds are bifunctional as they also inhibit Aβ aggregation. The data gathered from all publications regarding the chemical space occupied by butyrylcholinesterase inhibitors we believe will give an insight into the chemically active space occupied by this type of inhibitors and will hopefully facilitate future screening and result in an even deeper knowledge of butyrylcholinesterase inhibitors.