On the adaptation of broadcast transactions in token-passing fieldbus networks with heterogeneous transmission media

Broadcast networks that are characterised by having different physical layers (PhL) demand some kind of traffic adaptation between segments, in order to avoid traffic congestion in linking devices. In many LANs, this problem is solved by the actual linking devices, which use some kind of flow control mechanism that either tell transmitting stations to pause (the transmission) or just discard frames. In this paper, we address the case of token-passing fieldbus networks operating in a broadcast fashion and involving message transactions over heterogeneous (wired or wireless) physical layers. For the addressed case, real-time and reliability requirements demand a different solution to the traffic adaptation problem. Our approach relies on the insertion of an appropriate idle time before a station issuing a request frame. In this way, we guarantee that the linking devices’ queues do not increase in a way that the timeliness properties of the overall system turn out to be unsuitable for the targeted applications.

Microvascularização arterial da cóclea

RESUMO: Na descrição deste estudo foi utilizada a terminologia anatómica da Sociedade Brasileira de Anatomia adaptada ao português por J. A. Esperança-Pina de acordo com o tratado Anatomia Humana da Relação. Os actuais estudos sobre hipoacusia sensorioneural implicam um grupo crescente de situações, em que a lesão se situa ao nível da microvascularização coclear, daí que o conhecimento exacto da angiomorfologia normal se torne essencial na fase actual do conhecimento. A autora tem vindo a estudar, desde 1986, a angiomorfologia do ouvido Interno no modelo experimental, o Cobaio, utilizando várias técnicas microvasculares. sendo dado enfâse particular neste estudo à técnica de microscopia electrónica de varrimento em moldes vasculares. Os animais usados no presente estudo pertencem à espécie cavia porcellus, cobaio, por serem considerados na comunidade cientifica internacional como o melhor modelo experimental para estudo do ouvido interno, pelo facto de a morfologia coclear ser muito semelhante à do Homem e por isso ser um modelo fiável para cirurgia experimental e microdissecção. Este estudo foi realizado em 100 cobaios, cavia porcellus, de ambos os sexos com peso médio de 450g. A vascularização do ouvido interno, no cobaio como no homem, faz-se através dos ramos de divisão da artéria auditiva interna ou labiríntica. A artéria labiríntica origina-se como ramo colateral da artéria cerebelosa ântero-inferior a qual tem origem na artéria basilar ou na artéria vertebral. Embora no homem a artéria auditiva interna possa também destacar-se da artéria basilar e até da artéria vertebral, no cobaio em todos os casos estudados a sua origem verificou-se sempre na artéria cerebelosa ântero-inferior. A artéria labiríntica, ao passar abaixo do meato auditivo interno, divide-se na artéria vestibular anterior e na artéria coclear comum.A artéria vestibular anterior dirige-se para o nervo vestibular, emite vasa nervorum para este nervo e vasculariza o utrículo e os canais semicirculares. A artéria coclear comum origina dois ramos principais, a artéria vestíbulo‑coclear ou vestibular posterior no cobaio, a qual se destaca junto à espira basal da cóclea e a artéria coclear, como ramo terminal, que passa a denominar-se de artéria modiolar ou espiralada, após entrar no modíolo. A artéria modiolar ascende no modíolo promovendo através dos seus ramos colaterais e dos seus ramos terminais a microvascularização coclear, numa vascularização de órgão de tipo terminal. Ao longo do seu trajecto verificou‑se de modo constante uma redução gradual de calibre em cada uma das espiras, por emissão de ramos colaterais, sendo que o calibre da artéria na base da cóclea apresenta um valor que diminui gradualmente até ao ápice. A artéria modiolar origina em todo o seu trajecto ramos colaterais, cujo número diminui em valor absoluto da base para o ápice: Arteríolas radiárias internas, arteríolas de trajecto flexuoso que caminham junto às estruturas sensorioneurais da parede interna da cóclea, junto ao lábio timpânico da lâmina espiral óssea e na parede do próprio modíolo, que se relacionam intimamente com este. As arteríolas radiárias internas originam‑se no flanco da artéria modiolar espiralada. Contam‑se dez a doze em cada espira, extraordinariamente flexuosas desde a sua origem. As arteríolas radiárias internas originam como ramos colaterais, vários grupos de arteríolas de menor calibre, que vascularizam distintas regiões da parede interna da cóclea, as arteríolas do gânglio espiral, a rede espiral interna, as arteríolas de origem dos glomérulos de Schwalbe e a arteríola da lâmina basilar. As arteríolas radiárias externas importantes ramos colaterais da artéria modiolar espiralada promovem a vascularização de importantes estruturas da parede externa. Ao atingir o limite externo do ligamento espiral, as arteríolas radiárias externas dividem‑se em vários ramos arteriolares de menor calibre, ao longo da convexidade do limite externo do ligamento espiral, originando a rede capilar pós-estriada que ocupa a porção lateral do ligamento espiral e a rede capilar ad‑ -estriada, na sua porção mais medial em íntima relação com a estria vascular. A espira basal da cóclea apresenta grande riqueza de vascularização, com características particulares apenas a esta espira, a qual é metabolicamente a mais exigente. A arteríola da janela da cóclea aborda a janela da cóclea pela sua convexidade e divide-se numa rica rede vascular da qual emergem arteríolas pré-capilares que se ramificam em capilares, os quais se dirigem em profundidade penetrando a rampa timpânica da cóclea ao nível da espira basal. Importou neste estudo verificar quais as semelhanças em termos de calibre de estruturas análogas, na parede interna e na parede externa da cóclea, com particular incidência na rede capilar. Do estudo estatístico realizado com testes paramétricos de Tamahane e não paramétricos de Mann-Whitney, verifica-se que comparando todas as estruturas consideradas estas têm calibres diferentes, com excepção dos capilares da estria vascular e do ligamento espiral, pertencentes à parede externa da cóclea que têm calibres iguais aos capilares da rede espiral interna e aos capilares da parede interna da cóclea, dependentes das arteríolas da rede espiral interna. As redes capilares dependentes das arteríolas radiárias internas que vascularizam as estruturas sensorioneurais junto á parede interna do modiolo são em tudo semelhantes em termos de calibre às redes capilares da parede externa da cóclea, incluindo os capilares da estria vascular. Esta particularidade traduz num órgão com vascularização de tipo terminal,um mecanismo de controlo do fluxo sanguíneo coclear tão importante na parede interna como na parede externa da cóclea. ------------ ABSTRACT:Current studies on sensorineural hearing loss, imply a growing group of situations in which the lesion is located at the level of the cochlear microvasculature, hence the exact knowledge of normal angiomorfology becomes essential in current state of knowledge. The author has been studying since 1986, the angiomorfology of inner on the experimental model, the guinea pig, using various microvascular techniques being given particular emphasis in this study to the results of the technique of scanning electron microscopy on corrosion casts. The animals used in this study belong to the species cavia porcellus, guinea pig, to be considered in the international scientific community as the best experimental model for the study of the inner ear, the cochlear morphology is very similar to human and therefore a reliable model for experimental surgery and microdissection. This study was performed in 100 guinea pigs of both sexes with average weight of 450g. There shall be a brief description of embryology, anatomy and cochlear physiology in the light of developmental biology, regarding also the spatial location of the cochlea and the determinism of morphogenetic fields in their development and function. The cochlear transduction mechanism converts the sound wave in stimuli sound and so afferent auditory nerve fibres and deafness are closely related to the cochlear microvasculature. Cochlear ischemia is accompanied by immediate hearing loss. The different type of cochlear injury that leads to sensorineural deafness is well studied in presbycusis where an objective link with the audiometric pattern as been established. The sensory type of deafness, is closely related to the degeneracy of the organ of Corti and damage to the outer hair cells at the basal turn of the cochlea. Keeping in mind cochlear tonotopy with location of high frequency sounds at the level of the base of the cochlea, it explains the audiometric pattern with loss in high frequencies. The neural type of deafness, is characterized by neuronal loss with loss of descendant important neuronal afferents, with audiometric translation on a gradually curve with important loss of auditory discrimination. The metabolic type of deafness results in atrophy of the vascular stria, with consequent change in the potential of the endolymph by decreasing the vascular stria cells and changes in K + recycling mechanism. There is also a change in the morphology of the spiral ligament and the audiometric patern as a flattened curve with loss at all frequencies. Bearing in mind cochlear tonotopy and being characterized all types of sensorineural deafness, we may inquire to what extent the cochlear microvasculature, considering not only the cochlea as a whole but different regions of the inner wall and the outer wall of the cochlea, contributes to deafness. We analysed the entire cochlear morphology on scanning electron microscopy with particular emphasis on bone and membranous cochlea. The inner wall of the cochlea and intramodiolar structures such as the spiral ganglion, the morphology of its cell bodies and their axons are analyzed. The morphology of Corti’s organ is described in detail, with description and large detail of the inner and outer hair cells. Is then presented the study of the microvasculature itself. The spiral modiolar artery is observed with the diaphanization technique and the technique of scanning electron microscopy on corrosion vascular casts. After emergence of collateral branches of the greatest importance, the radiating internal and external arterioles, the modiolar artery gives rise to its terminal branches, the arterioles of the cochear apex. Arterial vasa vasorum and vasa nervorum are displayed with a great detail, which was not yet described in such detail in previous microvascular studies. The arterial radiating arterioles originate in the flank of the spiral modiolar artery in number of ten to twelve in each loop, and they vascularize through their branches the inner wall cochlear sensorineural structures located in the modiolus as the spiral ganglion and structures near the organ of Corti. Their caliber is above 20 μm on the basal turn and in the second loop it decreases to values between 12 and 20 μm, decreasing progressively to the apex of the cochlea.They arise near the modiolus or on their way in the spiral lamina forming vascular loops, and divide without presenting vascular constrictions in their divisions, originating new vascular loops of lower caliber. Internal ratiating arterioles originate as collateral branches several groups of smaller caliber arterioles, which vascularize distinct regions of the inner wall of the cochlea namely, the arterioles of the spiral ganglion, the internal spiral network, the arterioles of origin of the glomeruli of Schwalbe and the arterioles of the basilar membrane. The glomeruli of Schwalbe play an important functional role as relay-stations, in hemodynamic terms, to control the cochlear microvasculature. External radiating arterioles have their origin in the spiral modiolar artery, they are directed towards the outer wall of the cochlea and run through the roof of the scala vestibuli. Above the insertion of Reissner’s membrane on the external wall the external radiating arterioles originate the spiral ligament arterioles, which vascularize the spiral ligament, they divide into several arteriolar branches of smaller caliber, along the convexity of the outer edge of the spiral ligament. The connective tissue of the spiral ligament forms a mesh with supporting function of the highly specialized epithelium, where pericytes were identifiable. Next to its base there is the microvascular network of stria vascularis. The adstriated vascular network which is divided into a capillary network, the capillary network of stria vascularis. The stria vascularis, the only vascularized epithelium of the human body, plays an important role, forming an haemato-labyrintine barrier to assure labyrinthine endocochlear potential and transport of ions, essential for the mechanism of transduction of external hair cells. The cochlear basal turn has a special feature on its external wall, the region of the windows, the round windows giving access to scala tympani and the oval window thatleads into scala vestibuli, and so it is metabolic demanding. For their role in cochlear tonotopy the sensorineural structures and those of the external wall of the cochlea, are particularly vulnerable to hypoxia. Although the complementarity of all the techniques was important for three- -dimensional reconstruction of the microvasculature of the cochlea, the scanning electron microscopy technique, especially when we used the system Semafore was fundamental to perform precise morphometric mesures regarding all vascular structures.Regarding the capillaries of the inner and outer wall of the cochlea networks this technique allowed their characterization in morphometric terms. To conclude the capillaries of the inner wall and of the external wall of the cochlea have similar size. So although located at different cochlear regions, with a different functional role, in cochlear physiology these networks consist of capillaries of similar caliber. It seems to translate a cochlear blood flow control mechanism that is so important in the inner wall as in and the external wall of the cochlea to provide for in inner ear homeosthasia.

Ontology-based representation and generation of workflows for micro-task human-machine computation

Doctoral Program in Computer Science

Sex differences in the fetal heart rate variability indices of twins

Aims: To evaluate the differences in linear and complex heart rate dynamics in twin pairs according to fetal sex combination [male-female (MF), male-male (MM), and female-female (FF)]. Methods: Fourteen twin pairs (6 MF, 3 MM, and 5 FF) were monitored between 31 and 36.4 weeks of gestation. Twenty-six fetal heart rate (FHR) recordings of both twins were simultaneously acquired and analyzed with a system for computerized analysis of cardiotocograms. Linear and nonlinear FHR indices were calculated. Results: Overall, MM twins presented higher intrapair average in linear indices than the other pairs, whereas FF twins showed higher sympathetic-vagal balance. MF twins exhibited higher intrapair average in entropy indices and MM twins presented lower entropy values than FF twins considering the (automatically selected) threshold rLu. MM twin pairs showed higher intrapair differences in linear heart rate indices than MF and FF twins, whereas FF twins exhibited lower intrapair differences in entropy indices. Conclusions: The results of this exploratory study suggest that twins have sex-specific differences in linear and nonlinear indices of FHR. MM twins expressed signs of a more active autonomic nervous system and MF twins showed the most active complexity control system. These results suggest that fetal sex combination should be taken into consideration when performing detailed evaluation of the FHR in twins.

NovoTTF-100A versus physician's choice chemotherapy in recurrent glioblastoma: A randomised phase III trial of a novel treatment modality.

PURPOSE: NovoTTF-100A is a portable device delivering low-intensity, intermediate frequency electric fields via non-invasive, transducer arrays. Tumour Treatment Fields (TTF), a completely new therapeutic modality in cancer treatment, physically interfere with cell division. METHODS: Phase III trial of chemotherapy-free treatment of NovoTTF (20-24h/day) versus active chemotherapy in the treatment of patients with recurrent glioblastoma. Primary end-point was improvement of overall survival. RESULTS: Patients (median age 54years (range 23-80), Karnofsky performance status 80% (range 50-100) were randomised to TTF alone (n=120) or active chemotherapy control (n=117). Number of prior treatments was two (range 1-6). Median survival was 6.6 versus 6.0months (hazard ratio 0.86 [95% CI 0.66-1.12]; p=0.27), 1-year survival rate was 20% and 20%, progression-free survival rate at 6months was 21.4% and 15.1% (p=0.13), respectively in TTF and active control patients. Responses were more common in the TTF arm (14% versus 9.6%, p=0.19). The TTF-related adverse events were mild (14%) to moderate (2%) skin rash beneath the transducer arrays. Severe adverse events occurred in 6% and 16% (p=0.022) of patients treated with TTF and chemotherapy, respectively. Quality of life analyses favoured TTF therapy in most domains. CONCLUSIONS: This is the first controlled trial evaluating an entirely novel cancer treatment modality delivering electric fields rather than chemotherapy. No improvement in overall survival was demonstrated, however efficacy and activity with this chemotherapy-free treatment device appears comparable to chemotherapy regimens that are commonly used for recurrent glioblastoma. Toxicity and quality of life clearly favoured TTF.

Brain dynamics underlying training-induced improvement in suppressing inappropriate action.

Inhibitory control, a core component of executive functions, refers to our ability to suppress intended or ongoing cognitive or motor processes. Mostly based on Go/NoGo paradigms, a considerable amount of literature reports that inhibitory control of responses to "NoGo" stimuli is mediated by top-down mechanisms manifesting ∼200 ms after stimulus onset within frontoparietal networks. However, whether inhibitory functions in humans can be trained and the supporting neurophysiological mechanisms remain unresolved. We addressed these issues by contrasting auditory evoked potentials (AEPs) to left-lateralized "Go" and right NoGo stimuli recorded at the beginning versus the end of 30 min of active auditory spatial Go/NoGo training, as well as during passive listening of the same stimuli before versus after the training session, generating two separate 2 × 2 within-subject designs. Training improved Go/NoGo proficiency. Response times to Go stimuli decreased. During active training, AEPs to NoGo, but not Go, stimuli modulated topographically with training 61-104 ms after stimulus onset, indicative of changes in the underlying brain network. Source estimations revealed that this modulation followed from decreased activity within left parietal cortices, which in turn predicted the extent of behavioral improvement. During passive listening, in contrast, effects were limited to topographic modulations of AEPs in response to Go stimuli over the 31-81 ms interval, mediated by decreased right anterior temporoparietal activity. We discuss our results in terms of the development of an automatic and bottom-up form of inhibitory control with training and a differential effect of Go/NoGo training during active executive control versus passive listening conditions.

Aktiivinen melunvaimennus ampumaradalla

Aktiivinen melunvaimennus (active noise control, ANC) onkauan tunnettu ja sovellettu tekniikka. Kuitenkaan sitä ei ole aiemmin sovellettu impulssimaiseen satunnaiseen meluun. Tässä diplomityössä tutkitaan aktiivisenmelunvaimennuksen soveltuvuutta ampumaradan melunvaimennukseen. Ampumarata äärimmäisenä tapauksena asettaa korkean vaatimustason laitteistolle ja sen komponenteille. Suurin haaste on etsiä sopivat laitteiston komponentit, jotka tuottavat ja kestävät suurta äänenpainetasoa. Myös muuttuvat sääolosuhteet asettavat vaatimuksensa laitteiden mekaaniselle kestävyydelle sekä säänkestävyydelle. Työssä paneuduttiin erityisesti selvittämään, mitä kaupallisesti saatavilla olevia komponentteja voidaan hyödyntää aktiiviseen impulssimelunvaimennusjärjestelmään. Kaupallisten komponenttien soveltuvuutta aktiiviseen impulssimelunvaimennukseen analysoitiin laboratorio- ja kenttämittauksin. Työssä esitetään myös tulokset yksinkertaisella koelaitteistolla saavutetusta vaimennuksesta kenttäolosuhteissa.

Audiosignaalin digitaalinen käsittely aktiivisessa meluntorjunnassa

Meluntorjuntaan on perinteisesti käytetty passiivisia menetelmiä. Monissa sovelluksissa melua voidaan vaimentaa myös aktiivisella meluntorjunnalla. Tässä työssä tutkitaan aktiivisen meluntorjunnan signaalinkäsittelyä sekä signaalinkäsittelyyn soveltuvia laitteistoja. Lisäksi selvitetään ANC-järjestelmien (Active Noise Control) toimintaanja signaalinkäsittelyyn vaikuttavia tekijöitä. Tutkinnassa rajoitutaan yksikanavaisiin järjestelmiin. Esimerkkisovelluksena käytetään ulkotilan melunvaimennukseen soveltuvaa järjestelmää. Esimerkkijärjestelmään suunniteltiin signaalinkäsittelylaitteisto, jonka soveltuvuutta järjestelmän signaalinkäsittelyyn selvitettiin suorituskykymittauksin ja kokeellisin mittauksin.Lisäksi pohditaan signaalinkäsittelyn toteuttamista tutkittavassa järjestelmässä ja sovelluskohteessa.

Aktiivinen meluntorjunta ulkotiloissa

Ympäristömelu on nyky-yhteiskunnassa kasvava ongelma. Perinteisesti tätä melua on pyritty vähentämään passiivisen melunvaimennuksen avulla, kuten tienvarsien melumuureilla. Melua voidaan kuitenkin vaimentaa myös aktiivisellameluntorjunnalla (ANC, active noise control). Tässä työssä selvitetäänmitä ongelmia kohdataan, kun ANC-järjestelmää suunnitellaan ulkotiloihin ja mitä ominaisuuksia tällaiselta järjestelmältä vaaditaan. Työssä tutkitaan myös miten vaihtuvat ympäristöolosuhteet ja ulkoakustiset ilmiöt vaikuttavat ANC-järjestelmän toimintaan. Tutkimuksen pohjalta toteutetaan oma ANC-järjestelmä, jonka suorituskykyä työssä mitataan sekä komponentti- että järjestelmätasolla. Myös järjestelmän toimivuuteen vaikuttavia tekijöitä kartoitetaan mittausten avulla. Erikoistapauksena työssä selvitetään voiko suunnitellulla ANC-järjestelmällä vaimentaa impulssimaista melua paikallisesti.

Tuotantolinjan suorituskyvyn operatiivinen parantaminen ja ylläpitäminen

Työn tarkoitus on konelinjaan tutustumalla ja kyselyllä selvittää merkittävimmät kehitystä hidastavat ei-tekniset tekijät, jotka vaativat nykyistä enemmän panostusta suorituskyvyn nostamiseksi ja toiminnan tehostamiseksi valitulla konelinjalla. Työn tavoitteena on antaa suositus toimenpiteistä, joilla tehdyt ja tulevaisuudessa tehtävät parannustoimenpiteet viedään nykyistä paremmin käytäntöön. Kyselyn vastausten perusteella lähdetään etsimään haastatteluilla syvällisempiä vastauksia ja toimintaehdotuksia kyselyllä löydettyihin kehitystä vaativiin kohteisiin konelinjalla. Ongelmana eivät ole suorituskyvyn mittarit, vaan parannusten ja uusien toimintatapojen vieminen käytännön toiminnaksi.Nykyään ei-taloudelliset ja ei-tekniset tekijät ovat merkittävässä asemassa suorituskyvyn parantamisessa ja ylläpitämisessä. Henkilöstö on merkittävä voimavara, ja tämän vuoksi esimiesten yksi tärkeimmistä tehtävistä on motivoida työntekijät ja saada sitä kautta piilevät voimavarat tehokkaampaan käyttöön.Konelinjan henkilöstön tehokkaampi työskentely edellyttää läheistä yhteistyötä esimiesten ja työntekijöiden välillä, mitä edesauttaa esimerkiksi toimiva tiedonkulku. On löydettävä uusia toimintamalleja, joilla työntekijöiden osaaminen saadaan paremmin otettua huomioon

Calculation analysis of energy saving tools for fan and pump applications

This thesis analyses the calculation of FanSave and PumpSave energy saving tools calculation. With these programs energy consumption of variable speed drive control for fans and pumps can be compared to other control methods. With FanSave centrifugal and axial fans can be examined and PumpSave deals with centrifugal pumps. By means of these programs also suitable frequency converter can be chosen from the ABB collection. Programs need as initial values information about the appliances like amount of flow and efficiencies. Operation time is important factor when calculating the annual energy consumption and information about it are the length and profile. Basic theory related to fans and pumps is introduced without more precise instructions for dimensioning. FanSave and PumpSave contain various methods for flow control. These control methods are introduced in the thesis based on their operational principles and suitability. Also squirrel cage motor and frequency converter are introduced because of their close involvement to fans and pumps. Second part of the thesis contains comparison between results of FanSave’s and PumpSave’s calculation and performance curve based calculation. Also laboratory tests were made with centrifugal and axial fan and also with centrifugal pump. With the results from this thesis the calculation of these programs can be adjusted to be more accurate and also some new features can be added.

3D-tuoteyhdistelmämallien ja mittakuvien tuottaminen PDM-järjestelmästä

Tämä diplomityö on selvitystyö mittakuvien ja kolmiulotteisten CAD-mallien tuottamisesta. Mittakuvat ja 3D-CAD-mallit halutaan Neles-tuotemerkin omaaville tuotteille. Olennaisena osana työssä on tuotetiedonhallintajärjestelmä AtonPDM, koska mittakuvia ja malleja toivottaisiin hallittavan AtonPDM-järjestelmällä. Työ tehdään Metso Automationin (MA) Flow Control (FC) –liiketoimintalinjalle. Nykyiset mittakuvat aiheuttavat ongelmia sekä MA:ssa että asiakkaille. MA:ssa mittakuvien tekeminen kestää kauemmin kuin asiakas toivoisi. Nykyisen mittakuvaohjelmiston riittämättömät ominaisuudet aiheuttavat lisätyötä mittakuvien valmistuksessa. Asiakkaille mittakuvien viivästyminen on suunnittelua hidastava tekijä. Mittakuvissa olevat virheet ja puutteet vaikeuttavat asiakkaan suunnittelutyötä ja saattavat päästä läpi tarkatuksien myös loppusuunnitelmiin, jolloin seurauksena voi olla rahallisia menetyksiä. Tämän päivän putkistosuunnittelu hoidetaan suurimmaksi osaksi 3D-CADohjelmistoilla. Suunnittelua helpotetaan ja nopeutetaan valmiilla komponenttien 3Dmalleilla, joihin on liitetty tuotetietoa. Työssä on haastateltu MA:n henkilökuntaa, CAD-järjestelmien toimittajia ja asiakkaita. Haastattelut ovat työn tärkein tiedonlähde. Teoriatietoa on selvitetty kirjoista, lehdistä ja internetistä. Teoriaosiossa käydään läpi tuotetiedonhallinta (Product Data Management, PDM), tietokanta ja parametrinen mallintaminen. Työn lopputuloksena on pyritty saamaan kuvaus siitä miten tuotetaan 3D-CAD-mallit ja mittakuvat Neles-tuotteista käyttäen tiedonlähteenä AtonPDM:ää ja millaisia 3Dmallien ja mittakuvien tulee olla. Malleja ja mittakuvia tuottavaan järjestelmään on etsitty ratkaisuja CAD-ohjelmistoista. Ratkaisuja on verrattu keskenään ominaisuuksien, joustavuuden ja AtonPDM yhteensopivuuden perusteella.

Aktiivinen jännitteensäätö hajautetussa sähköntuotannossa

Hajautetun tuotannon määrä kasvaa jakeluverkossa tulevaisuudessa ja siksi jakeluverkon toiminta tulee muuttumaan aktiivisempaan suuntaan. Nykyisin tuotannon aiheuttamaa jännitteennousua rajoitetaan yleensä passiivisilla menetelmillä kuten vahvistamalla verkkoa. Tuotantolaitos ei tällöin osallistu jakeluverkon jännitteensäätöön. Tämä saattaa nostaa kapasiteetiltaan suurehkon tuotannon liittymiskustannukset niin korkeiksi, ettei tuotantolaitosta kannata rakentaa. Aktiivisella jännitteensäädöllä tuotantokapasiteettia voitaisiin merkittävästi kasvattaa nykyisissä jakeluverkoissa. Aktiivinen jännitteensäätö voi perustua joko paikalliseen säätöön, jolloin esim. tuotantolaitosta säädetään paikallisen jännitteen perusteella tai koordinoituun säätöön, jolloin verkon komponentteja säädetään kokonaisuutena. Työssä tutustutaan hajautettuun tuotantoon ja sen vaikutuksiin jakeluverkon jännitetasoissa sekä jännitteensäädössä. Työssä edetään passiivisesta jännitteensäädöstä aktiiviseen jännitteensäätöön. Aktiivisessa jännitteensäädössä tutustutaan muutamaan kirjallisuudessa esitettyyn algoritmiin ja käytännön toteutukseen. Työssä keskitytään vain verkon jännitetasoon, eikä muita jännitteen laadun ominaisuuksia oteta huomioon.

Sistema de alimentação gás-líquido para medidas de atividade catalítica

This note has as objective to present the advantages of the use of syringe-type pumps for the feeding of liquid reactants, together with mass flow controllers for gases, instead of the saturators, as it is generally accomplished. Among the advantages, the system with syringe pumps presents a greater flexibility in flow control as well as in composition compared with the system that uses saturator. In addition, the flow of the liquid reactants is known with precision in the syringe pump system.

Energy efficiency parameters in variable speed drives

The main purpose of this thesis is to measure and evaluate how accurately the current energy saving calculation in ABB’s new variable speed drive ACS850 works. The main topic of this thesis is energy-efficiency parameters. At the beginning of this thesis centrifugal pump, squirrel cage motor and variable speed drive, including some equations related to them, are being introduced. Also methods of throttling control and variable speed drive control of centrifugal pumps are being introduced. These subjects are introduced because the energy saving calculation in ACS850 is related to the centrifugal pumps usually driven by squirrel cage motors. The theory also includes short section about specific energy of pumping. Before measurements the current energy saving calculation of ACS850 is being introduced and analyzed. The measurements part includes introduction of measuring equipment, measurement results, summary and analysis of the measurements. At the end of this thesis a proposal for an improvement to the current energy saving calculation is being introduced and few proposals are made for new energy-efficiency parameters, which could be added to variable speed drives. At the end are also thoughts