546 research outputs found
Veljekset Laakkonen Oy - korjaamotoiminnan tehostaminen
Tämä insinöörityö on tehty kesän ja syksyn 2014 aikana Veljekset Laakkonen Oy:lle. Insinöörityön tavoitteena oli saada luotettavaa tietoa yhden toimipisteen henkilökunnalta korjaamon toiminnan tehokkuuteen vaikuttavista asioista.
Insinöörityön tutkimusmenetelmä oli kvalitatiivinen, eli tutkimus toteutettiin laadullisin menetelmin. Tietoa kerättiin korjaamon henkilökunnalta henkilökohtaisten haastatteluiden avulla. Tutkimukseen osallistuneet työntekijät työskentelevät Veljekset Laakkosella mekaanikkoina, työnjohtajina sekä varaosamyyjinä. Haastattelun tukena käytettiin haastattelulomaketta, joka sisälsi ennalta määritellyt kysymykset. Haastattelussa pyrittiin saamaan työntekijöiltä kattavasti tietoa korjaamon toiminnan tehokkuuteen vaikuttavista seikoista. Työntekijöillä oli myös haastattelun lopussa mahdollisuus vapaaseen sanaan, mikäli heillä oli korjaamon toimintaan liittyviä ehdotuksia tai toiveita.
Tutkimuksen tulosten perusteella korjaamotoiminnassa on muutamia osa-alueita, jotka kaipaavat muutoksia. Merkittävin tutkimuksessa esille noussut asia mekaanikkojen näkökulmasta on varaosapuolella asioinnin tehottomuus. Tutkimuksessa saatujen arvokkaiden tietojen pohjalta ideoitiin ongelmakohtiin kehitysehdotuksia, joilla korjaamotoimintaa saadaan tehostettua. Nämä kehitysehdotukset esitellään korjaamon johtotason henkilöstölle ja niitä tullaan hyödyntämään tulevaisuudessa korjaamotoiminnan kehittämisessä.The objective of this Bachelor’s thesis was to streamline the workshop operations of Veljekset Laakkonen Ltd and obtain reliable information about the matters effecting the efficiency of the workshop. This thesis was carried out during the summer and autumn of 2014.
The research method was a qualitative study which was conducted by using the information which was gathered from the workshop staff by interviewing them individually. The workers interviewed in this thesis were mechanics, foremen and spare part sellers. An interview form with pre-defined questions was used to support the interviews. The workshop staff answered questions considering the efficiency of the workshop and the objective was to gather information about their ideas on how to improve the efficiency of the workshop. The employees had also an opportunity to give their personal suggestions and recommendations for improving the workshop efficiency.
Based on the results of this thesis there seems to be a few issues that need improvement. The most significant issue from the mechanics’ point of view seems to be the inefficiency of the spare part department’s transactions. Based on the valuable information that was obtained during the interviews suggestions for improvement and streamlining the workshop operations were created. These improvement ideas will be presented to the management level of Veljekset Laakkonen Ltd
Life safety assessment in multi-storey building fires
Life safety is one of the most important objectives of Performance Based Fire-Design and is commonly considered to be achieved if building occupants escape the effects of the fire unharmed. Numerical simulations are often used to predict fire dynamics and factors affecting the evacuation capabilities of occupants.
The main scope of this research is to assess life safety in a multi-storey building fire. Statistics based fire risk assessment is used to choose the scenario to be simulated taking into consideration the damage severity and likelihood of occurrence. In the fire simulations, particular attention is given to the fuel modelling to consider the toxicity of combustion products and thus, its effects on the building occupants. Fire simulations results are then integrated with evacuation simulations. The fire risk assessment and fire/evacuation simulations are performed for a multi-storey hotel building located in Lecce, Italy
Effect of sprinklers on the patient's survival probability in hospital room fires
The effectiveness of sprinklers in protecting a patient in a hospital room fire was investigated by performing 26 sprinklered and four free-burn experiments in real hospital rooms equipped with water-based automatic suppression system. Three different fire loads were used: UL 1626 corner test fire and two different textile fires. The measurements included temperatures, pipe pressure, and concentrations of about 20 different gas compounds. Based on the measurement results, we calculated the Fractional Effective Dose (FED) and Fractional Irritant Concentration (FIC) –values, and estimated the likelihood of incapacitation as a function of time. The results showed that sprinklers maintained temperatures at low level and reduced toxicity, mainly through fire development control. In UL1626 and large textile fires, sprinklers decreased the patient's incapacitation probability from 0.9 or above to the level of 0.4. In small textile fires, the difference between the incapacitation probabilities of sprinklered fires and free-burns was less than the measurement uncertainty. FED results were sensitive to the calculation method due to the different treatment of NOx –gases.Peer reviewe
Chemical chaperone treatment reduces intracellular accumulation of mutant collagen IV and ameliorates the cellular phenotype of a COL4A2 mutation that causes haemorrhagic stroke
Haemorrhagic stroke accounts for approximately 20% of stroke cases and porencephaly is a clinical consequence of perinatal cerebral haemorrhaging. Here we report the identification of a novel dominant G702D mutation in the collagen domain of COL4A2 (collagen IV alpha chain 2) in a family displaying porencephaly with reduced penetrance. COL4A2 is the obligatory protein partner of COL4A1 but in contrast to most COL4A1 mutations, the COL4A2 mutation does not lead to eye or kidney disease. Analysis of dermal biopsies from patient and his unaffected father, who also carries the mutation, revealed that both display basement membrane (BM) defects. Intriguingly, defective collagen IV incorporation into the dermal BM was only observed in the patient and was associated with endoplasmic reticulum (ER) retention of COL4A2 in primary dermal fibroblasts. This intracellular accumulation led to ER-stress, unfolded protein response activation, reduced cell proliferation and increased apoptosis. Interestingly, absence of ER retention of COL4A2 and ER-stress in cells from the unaffected father indicate that accumulation and/or clearance of mutant COL4A2 from the ER may be a critical modifier for disease development. Our analysis also revealed that mutant collagen IV is degraded via the proteasome. Importantly, treatment of patient cells with a chemical chaperone decreased intracellular COL4A2, ER-stress and apoptosis, demonstrating that reducing intracellular collagen accumulation can ameliorate the cellular phenotype of COL4A2 mutations. Importantly, these data highlight that manipulation of chaperone levels, intracellular collagen accumulation and ER-stress are potential therapeutic options for collagen IV diseases including haemorrhagic stroke
Regulation of Type IV Collagen α Chains of Glomerular Epithelial Cells in Diabetic Conditions
An early feature of diabetic nephropathy is the alteration of the glomerular basement membrane (GBM), which may result in microalbuminuria, subsequent macroproteinuria, and eventual chronic renal failure. Although type IV collagen is the main component of thickened GBM in diabetic nephropathy, cellular metabolism of each α chains of type IV collagen has not been well studied. To investigate the regulation of α(IV) chains in diabetic conditions, we examined whether glucose and advanced glycosylation endproduct (AGE) regulate the metabolism of each α(IV) chains in the diabetic tissue and glomerular epithelial cells (GEpC). Glomerular collagen α3(IV) and α5(IV) chains protein were higher and more intense in immunofluorescence staining according to diabetic durations compared to controls. In vitro, mainly high glucose and partly AGE usually increased total collagen protein of GEpC by [3H]-proline incorporation assay and each α(IV) chain proteins including α1(IV), α3(IV), and α5(IV) in time-dependent and subchain-specific manners. However, the changes of each α(IV) chains mRNA expression was not well correlated to the those of each chain proteins. The present findings suggest that the metabolism of individual α(IV) chains of GBM is differentially regulated in diabetic conditions and those changes might be induced not only by transcriptional level but also by post-translational modifications
Modelling aerosol transport and virus exposure with numerical simulations in relation to SARS-CoV-2 transmission by inhalation indoors
We provide research findings on the physics of aerosol and droplet dispersion relevant to the hypothesized aerosol transmission of SARS-CoV-2 during the current pandemic. We utilize physics-based modeling at different levels of complexity, along with previous literature on coronaviruses, to investigate the possibility of airborne transmission. The previous literature, our 0D-3D simulations by various physics-based models, and theoretical calculations, indicate that the typical size range of speech and cough originated droplets (dPeer reviewe
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