Etäluentamittareiden tuomat tuotteistamismahdollisuudet sähkönmyyjille

Diplomityön tavoitteena oli selvittää etäluentamittareiden mahdollistamia tuotteita ja palveluita sekä niiden toteutettavuutta Mäntsälän Sähkö Oy:ssä. Työssä perehdytään yksityisasiakkaille suunnattuihin palveluihin, joita mittaritekniikka mahdollistaa. Mittarit tulee olla asennettuna 80%:lle verkkoyhtiön sähkönkäyttöpaikoista vuoteen 2014 mennessä. Mäntsälän Sähköllä mittareiden vaihtoprojektin alkamisen vuoksi haluttiin selvittää mahdollisten uusien tuotteiden toteutettavuutta. Työssä esitellään Mäntsälän Sähkö Oy:lle tulevan mittarijärjestelmän. Mittarijärjestelmä käyttää eri tietoliikennetapoja, jotka ovat GPRS, RS485 ja radio. Työ sisältää internet-paneelina suoritetun asiakaskyselyn, jossa selvitettiin asiakkaiden tarpeita ja mielipiteitä mahdollisten uusien tuotteiden osalta. Työssä käsiteltäviä tuotteita ovat kuormanohjaus, kysynnän hintajousto, spot-hinnoittelu, laskutus sekä raportointipalvelu. Kulutuksen hintajousto, kuormanohjaus ja spot-hinnoittelu toimivat toisiaan tukevina tuotteina. Tasasuuruista laskutusta voisi tarjota toteutuneen kulutuksen mukaisen laskutuksen ohessa lisäpalveluna. Raportointipalvelu internetissä on hyvä tapa toimittaa asiakkaalle lain velvoittamat tiedot.

Application of a Pid+fuzzy controller on the motion control system in machine tools

This work deals with an hybrid PID+fuzzy logic controller applied to control the machine tool biaxial table motions. The non-linear model includes backlash and the axis elasticity. Two PID controllers do the primary table control. A third PID+fuzzy controller has a cross coupled structure whose function is to minimise the trajectory contour errors. Once with the three PID controllers tuned, the system is simulated with and without the third controller. The responses results are plotted and compared to analyse the effectiveness of this hybrid controller over the system. They show that the proposed methodology reduces the contour error in a proportion of 70:1.

Instability of a square sheet under symmetric biaxial loading

An early experiment found that a square rubber sheet under symmetric biaxial loading may not remain square. This curious result has been one of the most instructive examples in finite elasticity. Here thermodynamic considerations are used to analyze this instability.

Unidirectional fiber-reinforced composite as an oral implant abutment material: Experimental studies of E-glass fiber/BisGMA-TEGDMA polymer in vitro

Fiber-reinforced composites (FRCs) are a new group of non-metallic biomaterials showing a growing popularity in many dental and medical applications. As an oral implant material, FRC is biocompatible in bone tissue environment. Soft tissue integration to FRC polymer material is unclear. This series of in vitro studies aimed at evaluating unidirectional E-glass FRC polymer in terms of mechanical, chemical, and biological properties in an attempt to develop a new non-metallic oral implant abutment alternative. Two different types of substrates were investigated: (a) Plain polymer (BisGMA 50%–TEGDMA 50%) and (b) Unidirectional FRC. The mechanical behavior of high fiber-density FRCs was assessed using a three-point bending test. Surface characterization was performed using scanning electron and spinning disk confocal microscopes. The surface wettability/energy was determined using sessile drop method. The blood response, including blood-clotting ability and platelet morphology was evaluated. Human gingival fibroblast cell responses - adhesion kinetics, adhesion strength, and proliferation activity - were studied in cell culture environment using routine test conditions. A novel tissue culture method was developed and used to evaluate porcine gingival tissue graft attachment and growth on the experimental composite implants. The analysis of the mechanical properties showed that there is a direct proportionality in the relationship between E-glass fiber volume fraction and toughness, modulus of elasticity, and load bearing capacity; however, flexural strength did not show significant improvement when high fiber-density FRC is used. FRCs showed moderate hydrophilic properties owing to the presence of exposed glass fibers on the polymer surface. Blood-clotting time was shorter on FRC substrates than on plain polymer. The FRC substrates also showed higher platelet activation state than plain polymer substrates. Fibroblast cell adhesion strength and proliferation rate were highly pronounced on FRCs. A tissue culture study revealed that gingival epithelium and connective tissue established an immediate close contact with both plain polymer and FRC implants. However, FRC seemed to guide epithelial migration outwards from the tissue/implant interface. Due to the anisotropic and hydrophilic nature of FRC, it can be concluded that this material enhances biological events related with soft tissue integration on oral implant surface.

Water relations of tree species growing on a rock outcrop in the "Parque Estadual de Itapuã", RS

Water relations of the tree species Myrsine umbellata Mart. ex A. DC., Dodonaea viscosa Jacq. and Erythroxylum argentinum O. E. Schulz, growing on a rock outcrop in the "Parque Estadual de Itapuã" (RS), were studied. Environmental (precipitation, temperature, soil water) and plant (water potential, vapor pressure deficit, stomatal conductance, transpiration, leaf specific hydraulic conductance, osmotic potential and cell wall elasticity) parameters were collected in five periods and pooled into two sets of data: wet and dry periods. Myrsine umbellata showed great stability of the plant parameters, including the maintenance of high pre-dawn (psiwpd) and mid-day (psiwmd) water potentials in the dry period (-0.48 and -1.12 MPa, respectively), suggesting the presence of a deep root system. Dodonaea viscosa and E. argentinum reached lower psiwpd (-1.41 and -1.97 MPa, respectively) and a greater degree of stomatal closure in the dry period, suggesting a shallower root system. Differential exposure to soil drought was also corroborated by differential drought effects on the whole-plant leaf specific hydraulic conductance (Gt). Correlation analysis pointed to weak correlations between psiwpd and g s. Erythroxylum argentinum was the only species to show osmotic adjustment in response to drought. It is suggested that M. umbellata has low tolerance to water deficits, adopting an avoidance behavior. The much lower values of psiw reached by D. viscosa and E. argentinum suggest a greater tolerance to drought by these species.

Heart rate variability in young adults - Reference values and associations with cardiometabolic risk factors and vascular properties. The Cardiovascular Risk in Young Finns Study.

Background: The function of the autonomic nervous system (ANS) can be evaluated with heart rate variability (HRV). Decreased HRV is associated with aging, the male sex, increased heart rate, and overall increased cardiometabolic risk. It has been hypothesized that early atherosclerotic vascular changes and ANS function are related. Aims: The aims were to assess reference values on HRV in young adults, and examine associations with HRV and cardiometabolic risk factors and metabolic syndrome (MetS) and to study relations between HRV and ultrasonographically measured vascular properties. Participants and methods: The present thesis is part of the Cardiovascular Risk in Young Finns Study. The thesis is based on the follow-up study in 2001, when the study individuals were 24-39 years of age. HRV data were available on 1 956 individuals. Results: HRV was inversely associated with age and heart rate (for all p<0.001). Highfrequency HRV (HF) was higher, and low-frequency HRV (LF) lower in women than men (p<0.0001 for both). MetS was associated with 11% decreased HF and 12% increased LF/HF-ratio in women, and 8% decreased HF and 4% increased LF/HF-ratio in men. Carotid artery distensibility was independently associated with HF and total HRV (for both p<0.05). Conclusions: The reference values in young adults were generated. Decreased HRV was associated with age, the male sex and increased heart rate. Women had higher HF and lower LF variability than men. MetS was related to decrease in HRV. The observed associations between carotid elasticity and HRV, supports the hypothesis that reduction in carotid elasticity may lead to decrease in autonomic cardiac control.

Chronic hypertension alters the expression of Cx43 in cardiovascular muscle cells

Connexin43 (Cx43), the predominant gap junction protein of muscle cells in vessels and heart, is involved in the control of cell-to-cell communication and is thought to modulate the contractility of the vascular wall and the electrical coupling of cardiac myocytes. We have investigated the effects of arterial hypertension on the expression of Cx43 in aorta and heart in three different models of experimental hypertension. Rats were made hypertensive either by clipping one renal artery (two kidney, one-clip renal (2K,1C) model) by administration of deoxycorticosterone and salt (DOCA-salt model) or by inhibiting nitric oxide synthase with NG-nitro-L-arginine methyl ester (L-NAME model). After 4 weeks, rats of the three models showed a similar increase in intra-arterial mean blood pressure and in the thickness of the walls of both aorta and heart. Analysis of heart mRNA demonstrated no change in Cx43 expression in the three models compared to their respective controls. The same 2K,1C and DOCA-salt hypertensive animals expressed twice more Cx43 in aorta, and the 2K,1C rats showed an increase in arterial distensibility. In contrast, the aortae of L-NAME hypertensive rats were characterized by a 50% decrease in Cx43 and the carotid arteries did not show increased distensibility. Western blot analysis indicated that Cx43 was more phosphorylated in the aortae of 2K,1C rats than in those of L-NAME or control rats, indicating a differential regulation of aortic Cx43 in different models of hypertension. The data suggest that localized mechanical forces induced by hypertension affect Cx43 expression and that the cell-to-cell communication mediated by Cx43 channels may contribute to regulating the elasticity of the vascular wall.

Effect of ultrastructural features on mechanical properties of softwood fiber

The main objective of this study was to develop mathematical model capable to describe the effect of ultrastructural features on the longitudinal modulus of elasticity of softwood fiber. Another objective was to identify, based on ultrastructural features, a potential explanatory factor for the mechanical difference between Norway spruce and Scots pine fibers and to demonstrate its influence utilizing developed modelling tools. According to the literature, the main difference between the pine and spruce fibers is the pit structure, which is clearly different in these fibers. The spruce fiber contains a lot of tiny pits, whereas the pits of the pine fiber are larger and the total number of them is smaller. The effect of the pits on the longitudinal modulus of elasticity of fiber is studied with both the analytical and the numerical model. The results show that, although the spruce fiber seems to contain clearly more pits, larger pits appearing in the pine fiber turn out to have a stronger influence on the longitudinal modulus of elasticity of the fiber. The effect of local variation of microfibril angle which occurs near the pits seems to be minor. Moreover, the results suggest that spruce fibers may have higher ultimate strength due to the more uniform straining behavior.

Food restriction induces in vivo ventricular dysfunction in spontaneously hypertensive rats without impairment of in vitro myocardial contractility

Cardiac structures, function, and myocardial contractility are affected by food restriction (FR). There are few experiments associating undernutrition with hypertension. The aim of the present study was to analyze the effects of FR on the cardiac response to hypertension in a genetic model of hypertension, the spontaneously hypertensive rat (SHR). Five-month-old SHR were fed a control or a calorie-restricted diet for 90 days. Global left ventricle (LV) systolic function was evaluated in vivo by transthoracic echocardiogram and myocardial contractility and diastolic function were assessed in vitro in an isovolumetrically beating isolated heart (Langendorff preparation). FR reduced LV systolic function (control (mean ± SD): 58.9 ± 8.2; FR: 50.8 ± 4.8%, N = 14, P < 0.05). Myocardial contractility was preserved when assessed by the +dP/dt (control: 3493 ± 379; FR: 3555 ± 211 mmHg/s, P > 0.05), and developed pressure (in vitro) at diastolic pressure of zero (control: 152 ± 16; FR: 149 ± 15 mmHg, N = 9, P > 0.05) and 25 mmHg (control: 155 ± 9; FR: 150 ± 10 mmHg, N = 9, P > 0.05). FR also induced eccentric ventricular remodeling, and reduced myocardial elasticity (control: 10.9 ± 1.6; FR: 9.2 ± 0.9%, N = 9, P < 0.05) and LV compliance (control: 82.6 ± 16.5; FR: 68.2 ± 9.1%, N = 9, P < 0.05). We conclude that FR causes systolic ventricular dysfunction without in vitro change in myocardial contractility and diastolic dysfunction probably due to a reduction in myocardial elasticity.

Immediate effects of submaximal effort on pulse wave velocity in patients with Marfan syndrome

Marfan syndrome (MS) is a dominant autosomal disease caused by mutations in chromosome 15, the locus controlling fibrillin 1 synthesis, and may exhibit skeletal, ocular, cardiovascular, and other manifestations. Pulse wave velocity (PWV) is used to measure arterial elasticity and stiffness and is related to the elastic properties of the vascular wall. Since the practice of exercise is limited in MS patients, it was of interest to analyze the acute effect of submaximal exercise on aortic distensibility using PWV and other hemodynamic variables in patients with MS with either mild or no aortic dilatation. PWV and physiological variables were evaluated before and after submaximal exercise in 33 patients with MS and 18 controls. PWV was 8.51 ± 0.58 at rest and 9.10 ± 0.63 m/s at the end of exercise (P = 0.002) in the group with MS and 8.07 ± 0.35 and 8.98 ± 0.56 m/s in the control group, respectively (P = 0.004). Comparative group analysis regarding PWV at rest and at the end of exercise revealed no statistically significant differences. The same was true for the group that used β-blockers and the one that did not. The final heart rate was 10% higher in the control group than in the MS group (P = 0.01). Final systolic arterial pressure was higher in the control group (P = 0.02). PWV in MS patients with mild or no aortic dilatation did not differ from the control group after submaximal effort.

Modification of commercial poly-lactide for extrusion coated food packaging applications

Poly-L-lactide (PLLA) is a widely used sustainable and biodegradable alternative to replace synthetic non-degradable plastic materials in the packaging industry. Conversely, its processing properties are not always optimal, e.g. insufficient melt strength at higher temperatures (necessary in extrusion coating processes). This thesis reports on research to improve properties of commercial PLLA grade (3051D from NatureWorks), to satisfy and extend end-use applications, such as food packaging by blending with modified PLLA. Adjustment of the processability by chain branching of commercial poly-L-lactide initiated by peroxide was evaluated. Several well-defined branched structures with four arms (sPLLA) were synthesized using pentaerythritol as a tetra-functional initiator. Finally, several block copolymers consisting of polyethylene glycol and PLLA (i.e. PEGLA) were produced to obtain a well extruded material with improved heat sealing properties. Reactive extrusion of poly-L-lactide was carried out in the presence of 0.1, 0.3 and 0.5 wt% of various peroxides [tert-butyl-peroxybenzoate (TBPB), 2,5-dimethyl-2,5-(tert-butylperoxy)-hexane (Lupersol 101; LOL1) and benzoyl peroxide (BPO)] at 190C. The peroxide-treated PLLAs showed increased complex viscosity and storage modulus at lower frequencies, indicating the formation of branched/cross linked architectures. The material property changes were dependent on the peroxide, and the used peroxide concentration. Gel fraction analysis showed that the peroxides, afforded different gel contents, and especially 0.5 wt% peroxide, produced both an extremely high molar mass, and a cross linked structure, not perhaps well suited for e.g. further use in a blending step. The thermal behavior was somewhat unexpected as the materials prepared with 0.5 wt% peroxide showed the highest ability for crystallization and cold crystallization, despite substantial cross linking. The peroxide-modified PLLA, i.e. PLLA melt extruded with 0.3 wt% of TBPB and LOL1 and 0.5 wt% BPO was added to linear PLLA in ratios of 5, 15 and 30 wt%. All blends showed increased zero shear viscosity, elastic nature (storage modulus) and shear sensitivity. All blends remained amorphous, though the ability of annealing was improved slightly. Extrusion coating on paperboard was conducted with PLLA, and peroxide-modified PLLA blends (90:10). All blends were processable, but only PLLA with 0.3 wt% of LOL1 afforded a smooth high quality surface with improved line speed. Adhesion levels between fiber and plastic, as well as heat seal performance were marginally reduced compared with pure 3051D. The water vapor transmission measurements (WVTR) of the blends containing LOL1 showed acceptable levels, only slightly lower than for comparable PLLA 3051D. A series of four-arm star-shaped poly-L-lactide (sPLLA) with different branch length was synthesized by ring opening polymerization (ROP) of L-lactide using pentaerythritol as initiator and stannous octoate as catalyst. The star-shaped polymers were further blended with its linear resin and studied for their melt flow and thermal properties. Blends containing 30 wt% of sPLLA with low molecular weight (30 wt%; Mwtotal: 2500 g mol-1 and 15000 g mol-1) showed lower zero shear viscosity and significantly increased shear thinning, while at the same time slightly increased crystallization of the blend. However, the amount of crystallization increased significantly with the higher molecular weight sPLLA, therefore the star-shaped structure may play a role as nucleating agent. PLLA-polyethylene glycol–PLLA triblock copolymers (PEGLA) with different PLLA block length were synthesized and their applicability as blends with linear PLLA (3051D NatureWorks) was investigated with the intention of improving heat-seal and adhesion properties of extrusion-coated paperboard. PLLA-PEG-PLLA was obtained by ring opening polymerization (ROP) of L-lactide using PEG (molecular weight 6000 g mol-1) as an initiator, and stannous octoate as catalyst. The structures of the PEGLAs were characterized by proton nuclear magnetic resonance spectroscopy (1H-NMR). The melt flow and thermal properties of all PEGLAs and their blends were evaluated using dynamic rheology, and differential scanning calorimeter (DSC). All blends containing 30 wt% of PEGLAs showed slightly higher zero shear viscosity, higher shear thinning and increased melt elasticity (based on tan delta). Nevertheless, no significant changes in thermal properties were distinguished. High molecular weight PEGLAs were used in extrusion coating line with 3051D without problems.

Obtention and characterization of gluten-free baked products

This work had as objective the development of gluten-free breads and muffins using rice flour and maize and cassava starches. From seven samples resulting from a Simplex-Centroid design, the sensory and instrumental analyses of specific volume, elasticity, and firmness were performed. For the sensory analysis, the optimized formulation contained 50% of rice flour and 50% of cassava starch, and for the instrumental evaluation, the optimal simultaneous point for the three conducted analyses were 20% of rice flour, 30% of cassava starch, and 50% of maize starch. A comparative analysis of specific volume, elasticity, firmness, and triangular test was performed with pre-baked, baked, and frozen bread. Physicochemical, nutritional, and microbiological analyses were performed for both bread and muffin according to the Brazilian legislation.

Effect of whey protein concentrate on texture of fat-free desserts: sensory and instrumental measurements

It is important to understand how changes in the product formulation can modify its characteristics. Thus, the objective of this study was to investigate the effect of whey protein concentrate (WPC) on the texture of fat-free dairy desserts. The correlation between instrumental and sensory measurements was also investigated. Four formulations were prepared with different WPC concentrations (0, 1.5, 3.0, and 4.5 wt. (%)) and were evaluated using the texture profile analysis (TPA) and rheology. Thickness was evaluated by nine trained panelists. Formulations containing WPC showed higher firmness, elasticity, chewiness, and gumminess and clearly differed from the control as indicated by principal component analysis (PCA). Flow behavior was characterized as time-dependent and pseudoplastic. Formulation with 4.5% WPC at 10 °C showed the highest thixotropic behavior. Experimental data were fitted to Herschel-Bulkley model. The addition of WPC contributed to the texture of the fat-free dairy dessert. The yield stress, apparent viscosity, and perceived thickness in the dairy desserts increased with WPC concentration. The presence of WPC promotes the formation of a stronger gel structure as a result of protein-protein interactions. The correlation between instrumental parameters and thickness provided practical results for food industries.

Sähkönmyyntiyhtiöiden riskienhallinnan haasteet ja kehittäminen

Diplomityön tavoitteena on esitellä sähkökaupan ja erityisesti sähköyhtiöiden kokemia sähkönmyynnin riskejä sekä kuvata sähkönmyyntiin liittyvää riskienhallinnan problematiikkaa. Tarkastelun näkökulmana on tietojärjestelmien ja saatavissa olevan tiedon hyödyntäminen energiayhtiöiden riskienhallinnassa. Toinen päätavoitteista on tutkia, kuinka saatavilla olevaa tiedon hyödyntämistä voidaan kehittää sähkönmyynnin hinnoittelussa sekä suojausten suunnittelussa. Työ toteutettiin työskentelemällä asiantuntijana energia-alaan keskittyneessä ohjelmistoyrityksessä sekä haastattelemalla yhdeksän suomalaisen sähkönmyyntiyhtiön henkilöitä riskienhallinnan haasteiden sekä tietojärjestelmien näkökulmasta. Saatavilla olevien tietojen nykyistä parempi hyödyntäminen ja automatisointi voivat auttaa pienentämään yhtiöiden riskitasoa ja parantaa menestymisen edellytyksiä sähkönmyynnin vähittäismarkkinoilla. Lisäksi kulloiseenkin markkinatilanteeseen sopivat sähkön hankintahinnan suojausstrategiat sekä monipuoliset dynaamiset hinnoittelumallit auttavat pienentämään yhtiön kokemia riskejä tai niiden vaikutuksia. Näiden hyödyntäminen vaatii laajaa ymmärrystä sähkö- ja johdannaismarkkinoiden toiminnasta sekä usein myös nykyisten tietojärjestelmien kehittämistä. Tulevaisuudessa yhä yleistyvä hajautettu tuotanto sekä kysynnän jousto asettavat tietojärjestelmille uusia vaatimuksia, jotka toteutuessaan mahdollistavat uudenlaisten palveluiden käyttöönoton sekä voivat tuoda tilaa myös alan uusille toimijoille. Työssä käsitellään energiayhtiöiden kokemia riskejä sähkönmyynnin näkökulmasta, esitellään alan yleisimmät riskit sekä keinot ja työkalut niiltä suojautumiseen. Työn lopuksi tarkastellaan sähkönmyynnin ja –hankinnan oleellisimpia prosesseja riskienhallinnan kehittämisen näkökulmasta.

Reciprocidade implícita e crescimento na economia internacional: uma perspectiva estruturalista

Implicit reciprocity and growth in the international economy: a structuralist perspective. This paper discusses some of the structuralist ideas about international coordination and growth in an international system formed by countries whose productive structures and technological capabilities are strongly asymmetric. These ideas are formalized taking as a point of departure the Keynesian Balance-of-Payments constrained growth model with two countries. To this model is added a function (based on the catching up literature) in which the income elasticity of the demand for exports and imports depends on the technology gap. The model allows for discussing the inter-relations between the fiscal and the industrial and technological policies. It also allows for finding the rate of growth of autonomous expenditure in the periphery which ensures that it will use all the foreign exchange it earns in promoting economic growth (the principle of "automatic reciprocity").