Magneettisten vetovoimien yhteisvaikutuksen laskentataulukko

Työssä kehitettiin Excel-pohjainen magneettisten vetovoimien yhteisvaikutuksen laskentatyökalu Ginolis Oy:lle. Tavoitteena oli hallita Excel-laskentataulukolla useiden magneettisten voimien yhteisvaikutus palettiin, jonka liikuttaminen ja paikoittaminen toteutetaan neodyymikestomagneeteilla. Laskentataulukon tarkoituksena on helpottaa suunnittelijoiden työtä, kun suunnitellaan erilaisia neodyymikestomagneetteihin perustuvia sovelluksia. Kehitystyö toteutettiin projektiluonteisesti. Työ aloitettiin selvittämällä, miten voidaan laskea magneettien välisiä voimia. Työssä päätettiin käyttää elementtimenetelmää, koska työhön sopivia laskentaohjelmistoja oli ilmaiseksi käytettävissä ja laskukaavojen hyödyntäminen olisi vaatinut ohjelmointia. Työstä laadittiin projektisuunnitelma, jossa projektin toteutus jaettiin karkeasti simulointiin ja simulointitulosten käsittelyyn, Excel-taulukon tekemiseen ja testaukseen. Laskentataulukon käytännön toimivuuden testaaminen jäi toteutumatta opinnäytetyössä. Opinnäytetyön tuloksena saatiin yksinkertainen laskentatyökalu magneettisten vetovoimien yhteisvaikutuksen laskemiseen. Laskentatyökalussa magneettisten voimien yhteisvaikutukset lasketaan elementtimenetelmällä lasketuista sama-akselisten ja samahalkaisijaisten magneettien välisistä vetovoimista. Magnetismia ei pystytä hallitsemaan yksinkertaisessa laskentatyökalussa, joten luotettaviin tarkasteluihin tarvitaan oikein tehtyjä elementtimenetelmään perustuvia simulaatioita

Weak smoking cessation awareness in primary health care before surgery : a real-world, retrospective cohort study

Objective: Tobacco smoking is a well-established risk factor for postoperative complications. Research on preoperative smoking cessation in primary health care is scarce. Design: This was a retrospective cohort study. Setting: The Stop Smoking before Surgery Project (SSSP) started in Porvoo, Finland, in May of 2016, involving both primary health care and specialized health care. The goals of the project were smoking awareness and preoperative smoking cessation. Subjects: Our study involved 1482 surgical patients operated at Porvoo Hospital between May and December of 2016. Main outcome measures: We studied the recording of smoking status in all patients, and ICD-10 diagnosis of nicotine dependency and the initiation of preoperative smoking cessation in current smokers. Variables were studied from electronic patient records, comparing primary health care referrals and surgical outpatient clinic records. Results: Smoking status was visible in 14.2% of primary health care referrals, and in 18.4% of outpatient clinic records. Corresponding rates for current smokers (n = 275) were 0.0 and 8.7% for ICD-10 diagnosis of nicotine dependence, and 2.2 and 15.3% for initiation of preoperative smoking cessation. The differences between primary health care referrals and outpatient clinic records were statistically significant for all three variables (pPeer reviewe

The effect of constitutive representations and structural constituents of ligaments on knee joint mechanics

Abstract Ligaments provide stability to the human knee joint and play an essential role in restraining motion during daily activities. Compression-tension nonlinearity is a well-known characteristic of ligaments. Moreover, simpler material representations without this feature might give reasonable results because ligaments are primarily in tension during loading. However, the biomechanical role of different constitutive representations and their fibril-reinforced poroelastic properties is unknown. A numerical knee model which considers geometric and material nonlinearities of meniscus and cartilages was applied. Five different constitutive models for the ligaments (spring, elastic, hyperelastic, porohyperelastic, and fibril-reinforced porohyperelastic (FRPHE)) were implemented. Knee joint forces for the models with elastic, hyperelastic and porohyperelastic properties showed similar behavior throughout the stance, while the model with FRPHE properties exhibited lower joint forces during the last 50% of the stance phase. The model with ligaments as springs produced the lowest joint forces at this same stance phase. The results also showed that the fibril network contributed substantially to the knee joint forces, while the nonfibrillar matrix and fluid had small effects. Our results indicate that simpler material models of ligaments with similar properties in compression and tension can be used when the loading is directed primarily along the ligament axis in tension

Gait alteration strategies for knee osteoarthritis:a comparison of joint loading via generic and patient-specific musculoskeletal model scaling techniques

Gait modifications and laterally wedged insoles are non-invasive approaches used to treat medial compartment knee osteoarthritis. However, the outcome of these alterations is still a controversial topic. This study investigates how gait alteration techniques may have a unique effect on individual patients; and furthermore, the way we scale our musculoskeletal models to estimate the medial joint contact force may influence knee loading conditions. Five patients with clinical evidence of medial knee osteoarthritis were asked to walk at a normal walking speed over force plates and simultaneously 3D motion was captured during seven conditions (0°-, 5°-, 10°-insoles, shod, toe-in, toe-out, and wide stance). We developed patient-specific musculoskeletal models, using segmentations from magnetic resonance imaging to morph a generic model to patient-specific bone geometries and applied this morphing to estimate muscle insertion sites. Additionally, models were created of these patients using a simple linear scaling method. When examining the patients’ medial compartment contact force (peak and impulse) during stance phase, a ‘one-size-fits-all’ gait alteration aimed to reduce medial knee loading did not exist. Moreover, the different scaling methods lead to differences in medial contact forces; highlighting the importance of further investigation of musculoskeletal modeling methods prior to use in the clinical setting

Workflow assessing the effect of gait alterations on stresses in the medial tibial cartilage:combined musculoskeletal modelling and finite element analysis

Abstract Knee osteoarthritis (KOA) is most common in the medial tibial compartment. We present a novel method to study the effect of gait modifications and lateral wedge insoles (LWIs) on the stresses in the medial tibial cartilage by combining musculoskeletal (MS) modelling with finite element (FE) analysis. Subject’s gait was recorded in a gait laboratory, walking normally, with 5° and 10° LWIs, toes inward (‘Toe in’), and toes outward (‘Toe out wide’). A full lower extremity MRI and a detailed knee MRI were taken. Bones and most soft tissues were segmented from images, and the generic bone architecture of the MS model was morphed into the segmented bones. The output forces from the MS model were then used as an input in the FE model of the subject’s knee. During stance, LWIs failed to reduce medial peak pressures apart from Insole 10° during the second peak. Toe in reduced peak pressures by −11% during the first peak but increased them by 12% during the second. Toe out wide reduced peak pressures by −15% during the first and increased them by 7% during the second. The results show that the work flow can assess the effect of interventions on an individual level. In the future, this method can be applied to patients with KOA

3D-pelinkehitys mobiililaitteille

Opinnäytetyössä oli tarkoituksena käydä läpi koodauksen perusteita ja sen jälkeen siirtyä Unity3D-peliohjelmointiin tekemään autopeli mobiililaitteille C#- ja Java-kielellä. Aluksi käytiin läpi perusteita, jonka jälkeen aloitettiin pelin tekeminen Unity3D:llä. Tulokseksi saatiin toimiva ja yksinkertainen peli, jonka tekemisessä oppi perusteet pelinteosta mobiililaitteille