Oak forests of Croatia

Hrastovi predstavljaju važnu komponentu šumske vegetacije u Hrvatskoj. Različite vrste hrastova dolaze u različitim vegetacijskim zajednicama diljem zemlje. Osim ekološke važnosti, bitni su i u industriji kao drvni materijal. Ovaj rad donosi pregled najvažnijih fitocenoza Hrvatske koje uključuju hrastove kao bitnu komponentu. Nakon kratkog osvrta na hrastove kao rod slijedi pregled po klimazonalnim zajednicama.The oaks represent an important component of forest vegetation of Croatia. Different oak species form a variety of phytocoenosis all over the country. Except for their ecological value, they're industrially important as wood material. This paper brings an overview of most important oak phytocoenosis in Croatia. A short review of oak species growing in Croatia is followed by an overview of its plant communities through climatic zones

Notranji in zunanji transportni upor v procesu nestacionarne adsorbcije vlage v les

The assumption that non-stationary sorption processes associated with wood canbe evaluated by analysis of their transient system response to the disturbance developed is undoubtedly correct. In general it is, in fact, possible to obtain by time analysis of the transient phenomenon - involving the transition into an arbitrary new state of equilibrium - all data required for a credible evaluation of the observed system. Evaluation of moisture movement during drying or moistening requires determination of external moisture transfer resistance from or to wood surfaces, as well as internal resistance. Time-dependent changes in the moisture content of the spruce (Picea abies Karst.) samples of different thickness were monitored gravimetrically, during which the frequency of weighing was in accord with thespeed of moistening. It was assumed that quasi-isothermal sorption processes associated with wood could be evaluated as first order systems. The characteristic time constant ? determines, wholly and uniformly, the time dependence of the sorption process for the relevant sorption range of wood tissue. The connection between the time constant and the thickness of the sample measured in the direction of the material flux is potential, with the power depending solely on the relationship between the external mass transfer convection and internal diffusion resistance. To determine the said resistances or coefficients of mass transfer convection and diffusivity, the experiment must be carried out on samples of varying thickness. It is only in this way that the external mass transfer convection and internal diffusion resistance can be correctly distinguished.Predpostavka, da je možno nestacionarne sorptivne procese, povezane z lesom, ovrednotiti z analizo njihovega časovnega prehodnega sistemskega odziva na nastalo motnjo, je nedvomno pravilna. V splošnem je namreč s časovno analizo prehodnega pojava, gre za prehod v poljubno novo ravnovesno stanje, možno pridobiti vse potrebne podatke za verodostojno vrednotenje opazovanega sistema. Vsak prehod v novo ravnovesno stanje je ne glede na lastnosti opazovanega sistema nestacionaren in kot tak primeren za analizo nestacionarnih pojavov, kot so na primer sorptivni procesi, povezani z lesom. Za analizo sorpcijskih transportnih značilnosti je treba poznati tako notranjidifuzijski kakor tudi zunanji masni prestopni upor. Časovno odvisne spremembe vlažnosti v smrekovih vzorcih (Picea abies Karst.) različnih debelinsmo spremljali gravimetrično, pri čemer je bila pogostnost tehtanja skladna hitrosti navlaževanja, se pravi v začetku največja, z naraščajočo masovzorcev pa se je zmanjševala. Predpostavljeno je bilo, da lahko sorbcijskeprocese, povezane z lesom, vrednotimo kot sisteme prvega reda. Značilna časovna konstanta ? določa časovno odvisnost sorbcijskega procesa za relevantno sorptivno območje lesnega tkiva v celoti in enolično. Zveza med časovno konstanto in debelino vzorca, merjeno v smeri snovnega toka, je potenčna, pri čemer je vrednost potence odvisna zgolj od razmerja med zunanjimprestopnostnim in notranjim difuzijskim uporom. Za določitev omenjenihuporov oziroma koeficientov snovne prestopnosti in difuzivnosti je treba napraviti eksperiment na vzorcih različnih debelin. Samo tako je mogoče korektno ločiti zunanji prestopnostni in notranji difuzijski upor

Structural Violence and Migration: Explaining Global and Local Total Institutions

Decades ago Johan Galtung presented his perspective on violence which includes the distinction between structural, direct and cultural violence. This paper tries to incorporate his approach and present the connection between structural violence and migrations with focus on immigration in the EU. The author argues that the consequence of structural violence is the appearance of two types of excluded spaces: a) global total institutions, which include countries or entire regions of economically less or underdeveloped countries; b) local total institutions within the economically developed countries, which include physical spaces (immigrant neighbourhoods, ghettos, prisons, detention centers for foreigners, etc.) and also social spaces of exclusion in which immigrants are put due to stereotype, prejudice and consequential discrimination.要旨数十年前、ヨハン・ガルトゥングは構造的、直接的、文化的な暴力の違いを含む暴力についての見解を示した。本稿ではその視角を取り入れながら、ＥＵ内の移民政策に焦点を当て構造的暴力と移住の関係について述べたい。構造的暴力とは、以下の２つのタイプの排除された空間の出現であると考えられる。a) 経済的に遅れている国や発展途上国などを含むグローバルな空間の出現。b) 物理的な空間を含む経済先進国内の地域空間（移民地域、ゲットー、刑務所、外国人拘留センターなど）や固定観念による先入観や差別を受け移民が排除される社会的空間の出現

What Does the (In)ability to React to the Covid-19 Coronavirus Reveal About Our Societies?

The many questions raised by the novel coronavirus pandemic go far beyond medical issues. Everything that was self-evident recently became impossible after the global spread of the virus. Despite the declarative EU emphasis of solidarity, the novel coronavirus pandemic clearly demonstrated the limits of solidarity and opened doors to nationalism. This crisis reveals all the anomalies of globalisation and the capitalist system in its currently dominant version of neoliberalism. The present crisis is indeed posing a serious challenge to the existing state system and capitalist economy. Evidence in support of this argument may be found in the surprising generosity of governments in many countries. Former enthusiastic advocates of austerity measures have come to realise that the legitimacy of the system is being tested at this time

Resonance in idling circular saw blades

V članku je prikazana analiza aerodinamičnega vzbujanja prosto vrtečega se krožnega žagnega lista. Ko se krožni žagni list prosto vrti, se zrak v pazdušnem prostoru ozobljenega dela orodja pri prehodu rezila loči od njegovihmejnih bočnih površin in tvori spremenljivo valovito brazdo oziroma turbolentni tok zraka. Posledica časovno spremenljivega turbolentnega toka je nastanek spremenljivega tlaka zraka ob površnah rezila, kar predstavlja aerodinamično vzbujanje žagnega lista. Za pojav prečnega resonančnega nihanja orodja ne zadošča zgolj aerodinamično generirana vzbujevalna sila s primerno frekvenco. Poleg omenjenega pogoja morata biti namreč izpolnjena še dodatna pogoja, in sicer morajo biti vzbujevalne tlačne razlike okoliškega zraka primerno velike, dušilne sposobnosti materiala nosilnega telesa žagnega lista pa dovolj majhne. Ugotovili smo, da nikoli nista vzbujena dva ali več lastnih načinov nihanja hkrati in da je prehod iz enega resonančnega stanja v drugega skokovit. Z naraščajočo frekvenco vrtenja se praviloma povečuje tudi območje vrtljajev, v katerem pride do aerodinamične vzbuditve lastnih nihajnih načinov.The article deals with the analysis of the aerodynamic excitation of a freely rotating circular saw blade. When the circular saw blade rotates freely, the air in the gullet spaces of the rim area of the tool separates (in the passing of the knife from its border flanking surfaces) and forms a variable waveform wake or turbulent airflow. The consequence of the time-variable turbulent airflow is the occurrence of variable air pressure along the knife surfaces, which constitutes the aerodynamic excitation of the saw blade. For the occurrence of transversal resonant vibration of the tool, there does not suffice only aerodynamically generated excitation force at a suitable frequency. In addition to the said condition, two additional conditions must also be met: the exciting pressure differences of the surrounding air must be adequately large, and the damping capabilities of the material of the saw plate sufficiently small. We have found that two or more natural manners of vibration are never excited simultaneously and that the transition from one resonant condition into another is abrupt. With the increasing frequency of rotation there is also, as a rule, an increase in the range of rotations in which the aerodynamic excitation of natural manners of vibration occurs

Slovenia: a case of a small, relatively new member country

The concept of differentiated integration (DI) is practically invisible in Slovenian politics. The analysis showed that the key words associated with DI are seldom used in parliamentary debates, coalition programmes or prime ministerial speeches. This suggests that the issue of DI is more a topic of academic discussion than of daily politics. While the low salience of DI in Slovenian political debates makes it hard to establish governmental positions in detail, the common thread throughout Slovenian foreign policy from independence in 1991 onwards has been that a strong and united EU is of key importance for Slovenia. The few instances where wording related to DI models was used reflect a concern about a multi-speed Europe, especially a fear that a multi-tier EU would mean fewer opportunities for future Slovenian governments and in general, fewer opportunities for smaller and/or less developed countries