KauNet: A Versatile and Flexible Emulation System

This is a poster on the KauNet network emulation system. As compared to other emulation system, KauNet is deterministic. The poster shows how patterns enforce determinism and how patterns can be used to emulate a satellite channel at the IP level

IP-Level Satellite Link Emulation with KauNet

Distributed applications and transport protocols communicating over a satellite link may react very strongly to conditions specific to that kind of link. Providing a evaluation framework to allow tests of real implementations of such software in that context is quite a challenging task. In this paper we demonstrate how the use of the general-purpose KauNet IP-level emulator combined with satellite-specific packet loss patterns can help by reproducing losses and delays experienced on a satellite link with a simple Ethernet LAN setup. Such a platform is an essential tool for developers performing continuous testing as they provide new features for e.g. video codecs or transport-level software like DCCP and its congestion control components

Children´s sleep in hospital : a parent´s perspective

Background: The need for sleep varies, but sick children have a greater need. Lack of sleep has a negative impact on many functions. There are no procedures for assessing children’s sleep problems while in hospital and research is limited. Aim: To describe parents’ experiences of what affects children´s sleep while admitted to hospital. Method: Inductive qualitative study at a pediatric medicine ward at Astrid Lindgren’s Children´s Hospital. Convenience sample included nine participants. Semi-structured interviews were performed using an interview guide. Qualitative content analysis was used. Results: The result is presented in four categories with subcategories; setting, illness, routines and experiences. The factors that had the most impact on their sleep, were nocturnal procedures and the effects of the disease. Conclusion: Being hospitalized can implicate both an improved or worsened sleep. How the child sleeps at home and how well prepared the child is has an impact. Children are often disturbed during the night in hospital, but it varies if it has any effect on the child or not.Bakgrund: Sömnbehovet varierar men sjuka barn har ett ökat behov. Sömnbrist har negativ inverkan på flera funktioner. Det saknas rutiner för att bedöma sömnproblem hos barn på sjukhus och forskningen är begränsad. Syfte: Att beskriva föräldrars upplevelser av vad som påverkar barns sömn under tiden de vistas på sjukhus. Metod: Induktiv kvalitativ studie på en medicinsk avdelning på Astrid Lindgrens barnsjukhus. Bekvämlighetsurval inkluderade 11 deltagare. Semistrukturerade intervjuer utfördes med intervjuguide. Analysmetod var kvalitativ innehållsanalys. Resultat: Resultatet presenteras i fyra kategorier med subkategorier; miljö, sjukdom, rutiner och erfarenheter. Det som påverkade sömnen mest var nattliga procedurer samt sjukdomens effekter. Slutsats: Sjukhusvistelse kan innebära både en förbättrad eller försämrad sömn. Hur barnet sover hemma och hur förberett barnet är har inverkan. Barn störs ofta nattetid vid sjukhusvistelse, men det varierar om det har någon påverkan på barnet eller inte

A NEAT Way to do Network Programming

This work has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No. 644334 (NEAT). The views expressed are solely those of the author(s)Peer reviewedPreprin

Using Triggers for Emulation of Opportunistic Networking

Opportunistic networks do not require the availability of an end-to-end path, but may instead take advantage of tem- porary connectivity opportunities. Opportunistic networks pose a challenge for network emulation as the traditional em- ulation setup where application/transport endpoints send/ receive packets from the network following a black box approach is no longer applicable. Instead opportunistic networking protocols and applications need to react to the dynamics of the underlying network beyond what is conveyed through the exchange of packets. In order to support emulation evaluations for such challenging applications we in this paper introduce the concept of emulation triggers that can emulate arbitrary cross-layer feedback and that are synchronized with the emulated scenario. The design and implementation of triggers in the KauNet emulator are described. The use of triggers in the context of opportunistic networking is brie y sketched

Effect of Impurities and the Alloying Elements on the Reactions between Copper and Tin

Tässä työssä tutkittiin eräiden elektroniikkakokoonpanoissa yleisesti esiintyvien metallien vaikutusta juoteliitoksen peruselementtien, kuparin ja tinan välisiin reaktioihin. Näitä metalleja olivat nikkeli, kulta, hopea, rauta ja sinkki. Tavoitteena oli selvittää näiden seosaineiden vaikutukset yhdistekerrosten kasvuun sekä rajapinnassa esiintyvien huokosten muodostumiseen. Työssä käytiin läpi elektroniikan kokoonpanoprosessia, juoteliitokselle tyypillisiä kuormitustilanteita ja käytettyjä luotettavuustestejä kirjallisuuteen ja tieteellisiin julkaisuihin perustuen. Myös diffuusioilmiön perusteita sekä Kirkendallin efektiä tarkasteltiin mahdollisena huokosten aiheuttajana. Lisäksi tarkasteltiin aiemmissa tutkimuksissa havaittuja seosaineiden vaikutuksia juoteliitoksen luotettavuuteen ja mikrorakenteeseen. Yhdisteiden kasvun ja huokosten esiintymisen tutkimiseksi kuparia ja tinaa seostettiin edellä mainituilla metalleilla ja näistä seoksista valmistettiin erilaisia juote-substraatti -kombinaatioita. Juottamisen jälkeen näitä pareja hehkutettiin vielä kiinteässä tilassa 125-150°C:n lämpötilassa 0-2560 tuntia. Pareista tehtyjä poikkileikkausnäytteitä tutkittiin pyyhkäisyelektronimikroskoopilla. Nikkelillä oli seosaineista voimakkain vaikutus rajapintareaktioihin. Jo 0,1 atomiprosentin nikkeliosuus kuparissa riitti ohentamaan Cu3Sn-kerrosta. Seoksilla Cu1Ni ja Cu2,5Ni havaittiin puolestaan huokosia yhdistekerrosten ja kuparin rajapinnassa. Suurimmat, viiden ja kymmenen prosentin nikkelipitoisuudet aiheuttivat Cu6Sn5-kerroksen äärimmäisen nopean kasvun, mutta syrjäyttivät kokonaan Cu3Sn-kerroksen. Nikkelin liukeneminen Cu6Sn5-kerrokseen Cu5Ni- ja Cu10Ni-seosten tapauksessa teki siitä mikrorakenteeltaan hyvin epäyhtenäisen. Muiden seosaineiden vaikutukset yhdisteiden paksuuskasvuun olivat puolestaan lieviä eikä huokosia esiintynyt millään muulla kuin nikkeliä sisältävillä seoksilla. Työn tärkeimmät johtopäätökset liittyvät nikkelipitoisuuden vaikutuksiin liitosrajapinnan yhdisteisiin ja rakenteeseen. Näiden tulosten pohjalta on myös mahdollista suunnitella tarkentavia jatkotutkimuksia esimerkiksi ilmiöiden esiintymiselle kriittisten nikkelipitoisuuksien määrittämiseksi.Effects of some alloying elements and impurities on the reactions between copper and tin were studied in this thesis. These metals were nickel, gold, silver, iron and zinc. The aim of this work is mainly to find out the effects of these elements on the thickness growth and void formation in the Cu-Sn interface. The microelectronics assembly process, typical loading conditions and the most used reliability tests methods were considered based on literature and scientific articles. Also the basics of the diffusion phenomena and especially the Kirkendall effect were reviewed as the possible cause of voiding. In addition to this, the effects of the alloying elements on reliability and microstructure were investigated. Copper and tin were alloyed with the metals and then the solder-substrate couples were prepared. These couples were soldered and then annealed at 125-150°C for 0-2560 hours. The cross-section samples were prepared and their examination was done by scanning electron microscope. Nickel had the largest effect on the interfacial reactions. Already the 0.1 at-% nickel content in substrate copper decreased the thickness of the Cu3Sn layer. Voids were detected at the interface with Cu1Ni and Cu2.5Ni alloys. The largest nickel contents, 5 and 10 at-%, caused the extremely large growth of Cu6Sn5 layer and displaced the Cu3Sn layer. The dissolution of nickel in Cu6Sn5 compound caused the clear non-uniformity on its microstructure. The other metals had no significant effects on thickness growth and no voids were detected with these metals. The most important conclusions of this thesis are related to effects of nickel contents on the interfacial structure and reactions. These results provide also the guidelines for further studies. The determination of critical nickel contents could be one topic of further considerations

Transistor Circuits

Contains a report on a research project

Transistor Circuits

Contains reports on two research projects

Transistor Circuits

Contains reports on two research projects

Transistor and Diode Studies

Contains reports on two research projects.Lincoln Laboratory (Purchase Order DDL-B222)United States Department of the ArmyUnited States Department of the NavyUnited States Department of the Air Force (Contract AF19(122)-458