The main objective of this thesis is to offer empirical evidence in support of the hypothesis that differences in firms' balance sheet structures may generate heterogeneous responses to monetary policy innovations. To this end in the second, introductory, chapter we start providing some evidence in favor of a large degree of heterogeneity in the asset and liability side of the balance sheet structure of manufacturing firms belonging to different European countries and different size classes. This static comparison is complemented with a quantitative assessment of the sensitivity of asset and liability items to business cycle conditions.In the third chapter we focus on a specific dimension along which the presence of heterogeneities in the balance sheet structure may induce different responses to a monetary policy action. In particular we address the existence of a channel of transmission of monetary policy, the cost-channel, that operates through the effect of interest expenses on the marginal cost of production. Such a channel is based on an active role of net working capital (inventories, plus trade receivables, less trade payables) in the production process and on the fact that variations in interest rate and credit conditions alter firms' short-run ability to produce final output by investing in net working capital. It has been argued that this mechanism may explain the dimension of the real effects of monetary policy, give a rationale for the positive short-run response of prices to rate increases (the "price puzzle") and call for a more gradual monetary policy response to shocks. The analysis is based on a unique panel, that includes about 2,000 Italian manufacturing firms and 14 years of data on individual prices and interest rates paid on several types of debt. We find robust evidence in favor of the presence of a cost-channel of monetary policy transmission, proportional to the amount of working capital held by each firm and with a size large enough to have non-trivial monetary policy implications. The empirical analysis of chapter three is based on the hypothesis that the type of heterogeneity that produces different firm level responses to an interest rate variation is well defined and measurable. On the contrary, most of the empirical literature that tests for the existence of heterogeneous effects of monetary policy on firms' production or investment choices is based on an ad hoc assumption of the specific firm level characteristic that should distinguish more sensitive from less sensitive firms. A similar degree of arbitrariness is adopted in selecting the number of classes of firms characterized by different responses to monetary policy shocks as well as in the selection of the cutoff points. The objective of chapter four is to apply a recent econometric methodology that building on data predictive density provides a well defined criteria to detect both the "optimal" dimension along which analyze firms' responses to monetary policy innovations and the "optimal" endogenous groups. The empirical analysis is focused on Italian manufacturing firms and, in particular, on the response of inventory investment to monetary policy shocks from 1983 to 1998. The main results are the following. In strike contrast with what is normally assumed in the literature in most of the cases it turns out that the optimal number of classes that is larger than two. Moreover orderings that are based on variables that are normally thought to be equivalent proxies for the size of the firm (i.e. turnover, total assets and level of employment) do not lead neither to the same number of groups nor to similar splitting points. Finally even if endogenous clusters are mainly characterized by different degrees of within group heterogeneity, with groups composed by smaller firms showing the largest dispersion, there also exist important differences in the average effect of monetary policy across groups. In particular the fact that some of the orderings do not show the expected monotonicity between the rank and the average effect appears to be one of the most remarkable aspects.

Abstract This study focused on web forming at a 5–10% consistency range, termed Ultra High Consistency (UHC). The study continued work done by Gullichsen with his research groups (1981–2007) and combined it with the HC forming research done by Valmet (HC, 1999–2004). The hypothesis was that by utilizing a rotor to fluidize suspension and a wedge to eliminate the free jet and thus prevent reflocculation, web forming at UHC is feasible at commercial speeds. The research method was experimental. The bulk of the research was conducted at pilot scale. A new UHC headbox was designed and mounted on a pilot former. The key elements of the headbox are the rotor and the wedge. As fluidization forms the base for UHC forming, this was evaluated at the pilot former using image analysis. In addition, fluidization was studied using a laboratory-scale device. Besides basic paper analysis, X-ray microtomography and sheet splitting methods were utilized to analyze the sheet structure. The results show that forming is possible within the focus area, 5–10% consistency and machine speeds of 150–600 m/min, although the operation potential of the UHC former is even wider. The results demonstrate that the wedge is needed for successful UHC forming, but the rotor is not required, providing the flow rate is sufficiently high. This indicates that various forces induced by the flow itself can be adequate to fluidize suspension for forming. The critical Reynolds number of full fluidization was found to be 200–250. The Reynolds numbers were estimated utilizing the linear dependencies found between the apparent viscosity and consistency, using the maximum mean flow velocities inside the headbox, and neglecting the possible rotation of the rotor. The corresponding critical flow velocities at 10% consistency are 12 and 19 m/s for a eucalyptus and pine pulp. The velocities are on average 70 and 60% lower than those given in the literature (40–50 m/s). The results reveal that the fiber orientation of UHC sheets is planar, the floc size of the web increases with consistency, the internal bond increases linearly with the floc size, and the tensile strength appears to decrease with increasing floc size. In consequence, it is postulated that the increase in the out-of-plane strength at the expense of in-plane strength with the consistency increase results from a more flocculated structure. / Tiivistelmä Tutkimus keskittyi rainanmuodostukseen 5–10 % sakeudessa. Sakeusalue nimitettiin ultra korkeaksi (lyhenne UHC). Tämä työ jatkoi Gullichsenin ja hänen tutkimusryhmiensä tutkimustyötä (1981–2007) ja samalla yhdisti sen Valmetin tekemään suursakeusrainaustutkimukseen (HC, 1994–2004). Työn hypoteesina oli, että käyttämällä roottoria massan fluidisoimiseen sekä ns. wedgeä eliminoimaan vapaa suihku ja estämään jälleenflokkaantuminen, rainanmuodostus UHC-sakeudessa on mahdollista kaupallisissa nopeuksissa. Tutkimusmetodi oli kokeellinen. Pääosa tutkimuksesta suoritettiin koekonemittakaavassa. Uusi UHC-perälaatikko suunniteltiin ja asennettiin koeformeille. Perälaatikon pääelementit ovat pyörivä roottori ja wedge. Koska fluidisointi muodostaa UHC-rainauksen perustan, fluidisointia evaluoitiin koekoneella käyttäen kuva-analyysiä sekä tutkittiin lisäksi käyttäen röntgenmikrotomografia ja arkin halkaisu -metodeja. Tulokset osoittavat, että rainaaminen on mahdollista määritellyllä fokusalueella, 5–10 %sakeudessa ja konenopeudella150–600 m/min, joskin UHC-formerin toimintapotentiaali on vieläkin laajempi. Tulokset osoittavat, että wedge tarvitaan onnistuneeseen UHC-muodostamiseen, mutta roottoria ei tarvita, mikäli virtausnopeus on riittävän suuri. Tämä tarkoittaa, että virtauksen aikaansaamat voimat voivat itsessään olla riittäviä massan fluidisoimiseksi rainaamista varten. Täyden fluidisaation kriittisen Reynoldsin luvun havaittiin olevan välillä 200–250. Reynoldsin luvut arvioitiin käyttäen löydettyjä viskositeetin ja sakeuden välisiä lineaarisia riippuvuuksia, päävirtauksen maksiminopeuksia perälaatikossa ja jättäen huomioon ottamatta mahdollinen roottorin pyöriminen. Reynoldsin lukuja vastaavat kriittiset virtausnopeudet 10 % sakeudessa ovat eukalyptus- ja mäntymassalla 12 ja 19 m/s. Nopeudet ovat keskimäärin 70 ja 60 % pienempiä kuin kirjallisuudessa annetut (40–50 m/s). Tulokset osoittavat, että UHC-arkeissa kuituorientaatio on tasomainen, rainan flokkikoko kasvaa sakeuden kasvaessa, palstautumislujuus kasvaa lineaarisesti flokkikoon kanssa ja vetolujuus näyttäisi laskevan flokkikoon kasvaessa. Näin ollen esitetään, että sakeuden kasvaessa tapahtuva palstautumislujuuden kasvu tasolujuuksien kustannuksella johtuu flokkaantuneemmasta rakenteesta.

This thesis asses the financial health of company WAX, s.r.o., in the years 2004 to 2006 at the basis of selected methods of the financial analysis. It contains proposals of possible solutions of identified problems which should result in the improvement of financial situation of the firm in future years.