Computational models for microvia fill process control

The microvia fill process is an electrochemical copper deposition process applied in the manufacturing of multilayered printed circuit boards (PCBs). It is the process where the metallic interconnections between adjacent signal layers of the multilayered PCB are made. The process chemistry is complex, including the interactions of several additive chemicals in addition to the underlying basic electrochemical processes of copper electrodeposition. To this day, the microvia fill process equipment set-ups utilized in the industry have none or very little automatic online control of the process variables. This is mostly because direct online measuring of the microvia fill process is practically impossible due to the vast number of microscopic features on a PCB, as well as to the small size of the features. The electronics industry is continuously striving to produce cheaper, smaller and more complex devices for an immeasurable number of applications. In the core of every electronics-appliance there is a PCB, which forms the chassis for the electronic components of the device as well as the signal paths between the components. Considering the enormous size of the electronics industry, as well as the ubiquitous nature of electronics, it is clear why PCB manufacturers consider that improving the microvia fill process technology is a relevant object for development. This doctoral thesis presents novel means for improving the microvia fill process through process simulation and model-based process design. The main results of the thesis are distributed parameter models, which together form the main components necessary for modeling a practical microvia fill electrolysis apparatus and designing a model-based control system for the process. Though the models are primarily based on physical and chemical first principles, the development work of all models presented in this thesis relies on experimental data that is gathered to parameterize and to validate the models. The thesis consists of a summary and nine publications, which address the modeling of the microvia fill process, the computational methods necessary for these models and the modeling of copper electrolysis systems in general

Intrauterine contraception after medical abortion : factors affecting success of early insertion

Objective: To assess the success and factors affecting early intrauterine device (IUD) provision after first trimester medical termination of pregnancy (MTOP). Study design: Subgroup analysis of a randomized contraceptive trial assessing the long-term effects of early provision of intrauterine contraception following abortion. Altogether, 606 women undergoing MTOP were included and followed for 3 months. The intervention group (n=307) was offered an IUD (either the levonorgestrel-releasing intrauterine system or copper-IUD) at a follow-up visit 1-4 weeks after MTOP. The control group (n=299) contacted primary health care for follow-up and contraceptive provision. Adverse events (infections, bleeding, residual tissue and incomplete abortion) were analyzed on intention-to-treat basis and IUD expulsions on per-protocol (PP) basis. Results: In the intervention group, 234 women (76.2%) received the IUD as scheduled, 46 later (altogether 91.2%). In the control group, the corresponding figures were 8 (2.7%) and 64 [altogether 24.1%, Odds ratio (OR) (95% Confidence interval (Cl)) = 32.7 (20.3-52.6)]. Eighty-five (27.7%) women in the intervention group and 38 (12.7%) in the control group received treatment (administration of antibiotics, misoprostol or surgical evacuation) because of presumed adverse event [2.63 (1.72-4.01)], mainly residual tissue. In the control group, 23 (60.5%) of these occurred during the first 2 weeks. IUD expulsion occurred in 12 (5.4%) of the 222 women in the intervention group (PP basis). Conclusions: When provided as part of abortion service, most early insertions following MTOP were performed as planned. The main reason for postponement was overdiagnosis of adverse events suspected at follow-up. The rate of IUD expulsion was similar to that reported previously. Implications: Early insertion following MTOP is safe, and the rate of IUD expulsion is low. Most adverse events possibly delaying IUD insertion occur early. Based on timing of adverse events in the control group, IUD insertion at approximately 2 weeks after completed MTOP seems optimal. (C) 2017 Elsevier Inc. All rights reserved.Peer reviewe

Mikrovian elektrolyyttisen täyttöpinnoitus: malli prosessimonitoroinnin kehitystä varten

Mikrovia on monikerrospiirilevyn yhden levyn läpi kulkeva reikä. Täyttämällä tämä reikä kuparilla muodostetaan yhteys kahdessa eri piirilevykerroksessa kulkevien johdinpiirien välille. Mikroviateknologia yhdistettynä moderniin piirisuunnitteluun mahdollistaa piirilevyjen johdintiheyden kasvattamisen ja näin ollen piirilevyjen sekä niille rakentuvien laitteiden pienentämisen. Viareiät täytetään elektrolyyttisesti rikkihappo-kuparisulfaatti-liuoksesta. Täyttöpinnoitusprosessissa mikrovia täyttyy täydellisesti kuparimetallilla ja reiän kohdalle jää peilikirkas kuparipinta valmiiksi seuraavan piirilevykerroksen ladontaa varten. Prosessin onnistuminen edellyttää kuparin pinnoittumista elektrolyyttiliuoksesta piirilevylle hallitun epätasaisesti siten, että kuparia pelkistyy eniten sinne, missä pinnassa on syvin reikä ja vähemmän sinne, missä pinta on tasainen tai siinä on kohouma. Ilmiö saadaan aikaan erityisten pinnoituslisäaineiden avulla. Mikroviojen pinnoitusastetta ei voida pinnoituksen aikana mitenkään mitata ja prosessin lunnonilmiöt huomioon ottava malli on ainut rationaalinen tapa arvioida pinnoituksen etenemistä. Tässä diplomityössä on kehitetty täyttöpinnoitusprosessin malli, joka luo perustan prosessin mallipohjaiselle ohjaukselle. Työssä esitellään pinnoitusprosessiin liittyvät perusilmiöt: diffuusion ja migraation aiheuttama massansiirto, sähkökemiallisen reaktion jännite-virta-tasapaino sekä läpivientireiän muodon muuttumisen vaikutukset. Kirjallisuusosassa käydään läpi monipuolisesti eri pinnoituslisäaineet sekä prosessissa esiintyvät pintakemialliset ilmiöt. Työssä kehitetty malli on toteutettu elementtimenetelmää käyttäen. Malli ottaa huomioon kaikki pinnoitusprosessin oleelliset fysikaaliset ja kemialliset ilmiöt sekä mallituskohteen muodonmuutokset. Myös pinnoituslisäaineiden vaikutus sisältyy malliin. Malli ennustaa pinnoitusprosessin vaatiman pinnoitusajan annetuissa prosessiolosuhteissa kohtalaisesti. Täyttöpinnoitusprosessin monimutkaisuuden sekä prosessiin liittyvien liikesalaisuuksien takia työn tulosta voidaan pitää hyödyllisenä. Kehitetty malli on sinällään käyttövalmis ja työn myötä täyttöpinnoitusprosessien ongelmakenttä on kartoitettu ja sen systemaattinen ratkaisu voi jatkua. Työn lopuksi kerrotaan tärkeimmät jatkotutkimuksen kohteet sekä niihin liittyvät koe- ja tutkimussuunnitelmat

Early provision of intrauterine contraception after first trimester induced abortion : complications, adherence to post-abortion care, recovery and risk of subsequent abortion during the first year

In Finland more than every third abortion is performed to a woman with history of previous abortion, which indicates suboptimal contraceptive use and inadequacy of postabortion contraceptive services. Previous studies have shown that long-acting reversible contraceptive (LARC) methods, especially intrauterine devices (IUD) are most efficient in preventing repeat unwanted pregnancy. IUDs can usually be inserted at the time of surgical termination of pregnancy (TOP). After medical TOP (MTOP), an IUD can be inserted when the abortion is shown to be complete, commonly 1–4 weeks afterwards, according to various recommendations. However, attendance at post-abortion contraceptive visits is poor, and thus the planned IUD insertion often fails. We have conducted a randomized trial assessing early postabortal IUD insertion provided comprehensively as a part of abortion services. Altogether 748 women undergoing a first trimester TOP were recruited and randomized into two groups. Women in the intervention group received an IUD (either a LNG-IUS or a Cu-IUD, according to the woman’s choice), at the hospital providing the TOP, either at the time of surgical TOP or at a follow-up visit 1–4 weeks after MTOP. Women in the control group were prescribed oral contraceptives and advised to contact their primary health care (PHC) unit for IUD insertion, according to the current practice and the national guideline. All study participants were provided with a questionnaire assessing anxiety, quality of life (QoL) and sexual well-being at baseline, as well as three months and one year after the TOP. The primary outcome was to assess the effects of the intervention on the incidence of subsequent TOP, when compared to the normal practice. In this thesis, the results of the first year are described. In addition, incidence of complications related to early IUD insertion, as well as compliance to post-abortion care and IUD insertion were assessed in women choosing MTOP. As secondary outcomes, mental health and sexual well-being during the first year after TOP was assessed. During the first year of follow-up after TOP, a significant difference between the two study groups was seen in the attendance at follow-up, in receiving the planned IUD, and in the incidence of repeat unwanted pregnancy. The early insertion of IUD after MTOP was safe and did not increase the risk of severe complications or IUD expulsions. In the entire study population general reduction of anxiety was seen at three month and one year, compared to baseline. Concordantly, a better quality of life was generally reported after three months. Regarding overall sexual well-being, there was no significant change during the follow-up. Better rates in the sexuality questionnaire, i.e. better sexual well-being, were associated with having a relationship, and correlated positively with frequency of intercourse, quality of life, and negatively with anxiety. Contraceptive method appeared to have little effect on overall sexual well-being. However, at three months, IUD users had better scores of sexual well-being, compared to users of other methods. This study shows that providing TOP and IUD insertion comprehensively at the same unit with minimal delay results in higher attendance at follow-up, higher uptake of IUD and a reduced need of subsequent TOP during one-year of follow-up.Raskaudenkeskeytys on tavallisin gynekologinen toimenpide maailmanlaajuisesti. Arviolta joka neljäs raskaus keskeytetään, mikä tarkoittaa lukumääräisesti n. 56 miljoonaa keskeytystä vuosittain. Vuonna 2017 Suomessa tehtiin 8,2 raskaudenkeskeytystä tuhatta hedelmällisessä iässä (15–49 vuotiasta) olevaa naista kohden. Näistä runsas kolmannes tehtiin naisille, joille oli jo aiemmin tehty yksi tai useampi keskeytys. Uusintakeskeytysten osuus kaikista keskeytyksistä onkin nousut viime vuosina, vaikka ehkäisyn saatavuus on yleisesti ottaen hyvä, ja ehkäisypalvelut ovat lakisääteisesti maksuttomia ja kuntien järjestämiä. Uusintakeskeytysten määrästä päätellen nykyiset ehkäisypalvelut eivät tavoita riittävän hyvin osaa naisista raskaudenkeskeytyksen jälkeen. Hedelmällisyys palautuu keskeytyksen jälkeen pian. Siksi uusien ei-toivottujen raskauksien estämiseksi nopeasti aloitettu tehokas raskaudenehkäisy on tärkeää. Pitkävaikutteiset raskaudenehkäisymenetelmät (kierukat ja ehkäisykapseli) ovat osoittautuneet kiistatta tehokkaimmiksi ehkäisymenetelmiksi. Tutkimusten mukaan kierukkaehkäisy vähentää uuden ei-toivotun raskauden riskiä jopa kolmikertaisesti verrattuna ns. lyhytvaikutteisiin menetelmiin kuten ehkäisypilleriin, -renkaaseen tai -laastariin, tai estemenetelmiin. Viimeisen 15 vuoden aikana Suomessa valtaosa raskaudenkeskeytyksistä on tehty lääkkeellisesti, ja vuonna 2017 vain 3% tehtiin imukaavinnalla. Monista hyvistä puolistaan huolimatta tämä kehitys asettaa haasteita kierukkaehkäisyn aloitukselle. Kaavinnan yhteydessä kierukka on voitu useimmiten asettaa välittömästi. Viimeisimpien tutkimusten valossa välitön (alle 72h) kierukan asetus lääkkeellisen raskaudenkeskeytyksen jälkeen on turvallista, mutta lisää kierukan osittaisen poistumisen (ekspulsio) riskiä. Tutkimuksissa, joissa kierukka on asetettu noin viikon kuluttua lääkkeellisestä keskeytyksestä, ekspulsioriskin ei ole todettu kohonneen myöhempään asetusajankohtaan verrattuna. Oma tutkimuksemme on viisivuotinen seurantatutkimus, johon osallistui 748 ensimmäisen raskauskolmanneksen keskeytykseen Kätilöopiston sairaalaan tulevaa täysi-ikäistä, kierukkaehkäisystä kiinnostunutta helsinkiläistä naista. Heidät satunnaistettiin kahteen eri hoitopolkua noudattavaan ryhmään. Kierukkaryhmään kuuluville asetettiin kierukka sairaalassa joko kaavintakeskeytyksen yhteydessä tai seurantakäynnillä 1–4 viikkoa lääkkeellisen keskeytyksen jälkeen. Verrokkiryhmään kuuluville aloitettiin tablettiehkäisy ja heitä ohjattiin nykyisen hoitokäytännön mukaisesti ottamaan yhteyttä omalle terveysasemalle jälkitarkastusta ja kierukkaehkäisyn aloitusta varten. Osallistujien terveydentilaa, ahdistuneisuutta, elämänlaatua ja seksuaalista hyvinvointia seurattiin kyselylomakkein tutkimuksen alkaessa, sekä kolmen kuukauden ja vuoden kuluttua. Keräsimme kolmen kuukauden ajalta tiedot kaikista raskaudenkeskeytykseen tai kierukkaan liittyvistä sairaalakäynneistä tarkastellaksemme komplikaatioita ja mahdollisia varhaiseen kierukkaehkäisyn aloitukseen liittyviä haittavaikutuksia. Vuoden seurannan jälkeen keräsimme tiedot uusista raskaudenkeskeytyksistä Terveyden ja hyvinvoinnin laitoksen (THL) raskaudenkeskeytysrekisteristä sekä sairaalan potilastietojärjestelmästä. Tarkastelimme lisäksi jälkitarkastusten ja suunniteltujen kierukanasetusten toteutumista sekä niihin vaikuttavia taustatekijöitä molemmissa ryhmissä. Varhainen kierukan asetus lääkkeellisen raskaudenkeskeytyksen jälkeen ei lisännyt vakavien komplikaatioiden eikä ekspulsion riskiä kolmen kuukauden seurannan aikana. Kierukkaryhmään kuuluvista naisista merkittävästi useampi kävi suunnitellussa jälkitarkastuksessa (93% vs. 66%) ja heille myös asetettiin kierukka kolmen kuukauden aikana useammin kuin verrokkiryhmään kuuluville (90% vs. 26%). Tutkimusinterventio vähensi uusien keskeytysten tarvetta lähes kolminkertaisesti verrattuna nykyiseen normaaliin ehkäisypalvelukäytäntöön. Kierukkaryhmässä 6 (1.6%) naiselle ja verrokkiryhmässä 17 (4.6%) naiselle tehtiin uusi raskaudenkeskeytys vuoden seurannan aikana. Tutkimukseen osallistujien elämänlaatu koheni ja ahdistuneisuus väheni yleisesti tutkimuksen aloituksen ja kolmen kuukauden seurannan välillä, ja säilyi sen jälkeen oleellisesti ennallaan vuoden ajan. Merkittävä osa naisista koki merkittävää ahdistusta raskauden keskeytyksen aikoihin; erityisesti näillä naisilla ahdistus lieventyi kolmen kuukauden aikana selvimmin. Seksuaalinen hyvinvointi ei tutkimukseemme osallistuvilla naisilla muuttunut oleellisesti vuoden seurannan aikana. Raskaudenkeskeytyksellä tai sen jälkeen aloitetulla ehkäisyllä ei ollut oleellista vaikutusta koettuun seksuaaliseen hyvinvointiin. Siihen olivat sitä vastoin yhteydessä koettu hyvä elämänlaatu, vähäinen ahdistuneisuus, parisuhde sekä seksuaalinen aktiivisuus

Provision of intrauterine contraception in association with first trimester induced abortion reduces the need of repeat abortion : first-year results of a randomized controlled trial

Correction: Volume: 34 Issue: 3 Pages: 587-588 DOI: 10.1093/humrep/dey376 Published: MAR 2019 Accession Number: WOS:000461140700021STUDY QUESTION: Can the need of subsequent abortion be reduced by providing intrauterine contraception as a part of the abortion service? SUMMARY ANSWER: Provision of intrauterine devices (IUDs) in association with first trimester abortion more than halved the incidence of repeat abortion during the first year of follow-up. WHAT IS KNOWN ALREADY: Following abortion, the incidence of subsequent abortion is high, up to 30-40%. In cohort studies, intrauterine contraception has reduced the need of repeat abortion by 60-70%. STUDY DESIGN, SIZE, DURATION: A randomized controlled trial. The main outcome measure was the incidence of subsequent induced abortions during the follow-up. Altogether 751 women seeking first trimester induced abortion were recruited and randomized into two groups. Randomization was accomplished by computer-assisted permuted-block randomization with random block sizes of four to six. The investigators did not participate in randomization, which was done before commencing the study. The participants were recruited between 18 October 2010 and 21 January 2013. PARTICIPANTS, SETTINGS, METHODS: The inclusion criteria were age >= 18 years, duration of pregnancy This study was conducted in collaboration between the Department of Obstetrics and Gynaecology, University of Helsinki and Helsinki University Hospital, and Centralized family planning of the City of Helsinki. The intervention group (n = 375) was provided with intrauterine contraception (either the levonorgestrel-releasing intrauterine system or copper-releasing intrauterine device) immediately following surgical abortion (18.1%) or at a follow-up 2-4 weeks after medical abortion (81.9%). Women in the control group were prescribed oral contraceptives and advised to contact their primary healthcare unit for a follow-up visit and further contraceptive services according to national guidelines. The women were followed-up to 28 February 2014 by using the Finnish National Abortion Registry, Helsinki University Hospital electronic database and clinical follow-up visit at 1 year. MAIN RESULTS AND THE ROLE OF CHANCE: The median age of the whole study group was 27 years and 44% had a history of induced abortion(s). During the follow-up year the number of women requesting subsequent abortion was significantly lower in the intervention than in the control group (9/375 [2.4%] versus 20/373 [5.4%], difference -3.0 [95% CI -6.0 to -0.2] percentage points, P = 0.038, according to intention-to-treat analysis and 5/346 [1.4%] versus 20/357 [5.6%], difference -4.2(-7.2 to -1.4) percentage points, P = 0.003, according toper-protocol analysis, respectively). Provision of intrauterine contraception was safe with rate of infection and expulsion similar to those reported previously. LIMITATIONS, REASONS FOR CAUTION: The powercalculation was calculated for a 5-year follow-up. However, significant differences between the two groups were already seen after 1 year. The present study was performed in a single clinic, where, similar to 15% of all abortions in Finland are performed. WIDER IMPLICATIONS OF THE FINDINGS: In order to decrease the need of subsequent abortions, IUDs should be provided at the time of abortion.Peer reviewe

Predicting poor compliance with follow-up and intrauterine contraception services after medical termination of pregnancy

Background Attendance at post-abortion follow-up visits is poor, but little is known about factors affecting it. Objective To assess the factors associated with non-compliance with post-abortion services and to evaluate differences in rates of attendance and intrauterine device (IUD) insertion according to the type of service provision. Methods 605 women undergoing a first trimester medical termination of pregnancy (MTOP) and planning to use intrauterine contraception were randomised into two groups. Women in the intervention group (n=306) were booked to have IUD insertion 1-4 weeks after the MTOP at the hospital providing the abortion, while women in the control group (n=299) were advised to contact their primary healthcare (PHC) centre for follow-up and IUD insertion. Results In the intervention group, 21 (6.9%) women failed to attend the fol low-up visit, whereas in the control group 67 (22.4%) women did not contact the PHC to schedule a follow-up (p Conclusions Factors predicting low compliance with post-MTOP fol low-up are few. Comprehensive provision of abortion care and post-abortion services seems beneficial for minimising the loss to fol low-up and delay in initiation of effective contraception.Peer reviewe

Validation of Neural Network-based Fault Diagnosis for Multi-stack Fuel Cell Systems: Stack Voltage Deviation Detection☆

Abstract This paper presents (i) an algorithm for the detection of unexpected stack voltage deviations in an Solid Oxide Fuel Cells (SOFC)-based power system with multiple stacks and (ii) its validation in a simulated online environment. The algorithm is based on recurrent neural networks (RNNs) and is validated by using operating data from the Wartsila WFC20 multi-stack SOFC system. The voltage deviation detection is based on statistical testing. Instead of a hardware implementation in the actual power plant, the algorithm is validated in a simulated online environment that provides data I/O communication based on the OPC (i.e. Object Linking and Embedding (OLE) for Process Control) protocol, which is also the technology utilized in the real hardware environment. The validation tests show that the RNN-based algorithm effectively detects unwanted stack voltage deviations and also that it is online-viable

On the use of neural networks and statistical tools for nonlinear modeling and on-field diagnosis of solid oxide fuel cell stacks

Abstract The paper reports on the activities performed within the European funded project GENIUS to develop black-box models for modeling and diagnosis of solid oxide fuel cell (SOFC) stacks. Two modeling techniques were investigated, i.e. Neural Networks (NNs) and Statistical Tools (STs). The deployment of NNs was twofold: Recurrent Neural Networks (RNNs) and an NN classifier were developed to simulate transient operation of SOFCs and identify some specific faults that may occur in such devices, respectively. On the other hand, STs are based on a stepwise multiple regression. Data for model development were obtained from experiments specifically designed to reach maximal information content. The final aim was to obtain highly general models of SOFC stacks' operation in both transient and steady state. All the developed black-box models exhibited high accuracy and reliability on both training and test data-sets. Moreover, the black-box models were also proven effective in performing real-time monitoring and degradation analysis for different SOFC stack technologies

Early provision of intrauterine contraception as part of abortion care-5-year results of a randomised controlled trial

STUDY QUESTION: Can the incidence of subsequent termination of pregnancy (TOP) be reduced by providing intrauterine contraception as part of the abortion service? SUMMARY ANSWER: Provision of an intrauterine device (IUD) as part of TOP services reduced the need for subsequent TOP but the effect was limited to the first 3 years of the 5-year follow-up. WHAT IS KNOWN ALREADY: An IUD is highly effective in preventing subsequent TOP. Prompt initiation of IUD use leads to a higher usage rate during follow-up, as compliance with post-TOP IUD insertion visits is low. STUDY DESIGN, SIZE, DURATION: The objective of this randomised controlled trial was to assess the effect of early comprehensive provision of intrauterine contraception after TOP, with primary outcome being the incidence of subsequent TOP during the 5 years of follow-up after the index abortion. This study was conducted at a tertiary care centre between 18 October 2010 and 21 January 2013. Altogether, 748 women undergoing a first trimester TOP were recruited and randomised into two groups. The intervention group (n = 375) was provided with an IUD during surgical TOP or 1-4 weeks following medical TOP at the hospital providing the abortion care. Women in the control group (n = 373) were advised to contact primary health care for follow-up and IUD insertion. Subsequent TOPs during the 5-year follow-up were identified from the Finnish Register on induced abortions. PARTICIPANTS/MATERIALS, SETTING, METHODS: The inclusion criteria were age >= 18 years, duration of gestation MAIN RESULTS AND THE ROLE OF CHANCE: The overall numbers of subsequent TOPs were 50 in the intervention and 72 in the control group (26.7 versus 38.6/1000 years of follow-up, P = 0.027), and those of requested TOPs, including TOPs and early pregnancy failures, were 58 and 76, respectively (30.9 versus 40.8/1000, P = 0.080). Altogether 40 (10.7%) women in the intervention and 63 (16.9%) in the control group underwent one or several subsequent TOPs (hazard ratio 1.67 [95% CI 1.13 to 2.49], P = 0.011). The number of TOPs was reduced by the intervention during years 0-3 (22.2 versus 46.5/1000, P = 0.035), but not during years 4-5 (33.3 versus 26.8/1000, P = 0.631). LIMITATIONS, REASONS FOR CAUTION: Both medical and surgical TOP were used. This may be seen as a limitation, but it also reflects the contemporary practice of abortion care. The immediate post-TOP care was provided by two different organizations, allowing us to compare two different ways of contraceptive service provision following TOP. WIDER IMPLICATIONS OF THE FINDINGS: Providing TOP and IUD insertion comprehensively in the same heath care unit leads to significantly higher rates of attendance, IUD use and a significantly lower risk of subsequent TOP.Peer reviewe