REMEMBER TO NOT FORGET: Construction of the Serbian collective memory through media reportage of the commemorations of the Kosovo War

In 2019, Serbia marked the 20th anniversary of the end of the Kosovo War through numerous commemorations that received significant media coverage. Through qualitative, ideographical research, this article explores how the Serbian media constructs the collective memory of the 1999 NATO intervention. By using thematic analysis and coding, the article analyses a total of ten newspaper articles from two newspaper outlets. Three themes emerged from the analysis: 1. “Unjustified and premeditated bombing campaign”; 2. “Do not forget Milica!”; and 3. “No justice?”. The thread that unites all three themes is the element of victimhood that the media frames and positions at the centre of collective memory. The article concludes that this view of victimhood is not an anomaly in history, but is aligned with the existing collective memory through the continuous emphasis on the suffering of Serbs

Long induced paths in expanders

We prove that any bounded degree regular graph with sufficiently strong spectral expansion contains an induced path of linear length. This is the first such result for expanders, strengthening an analogous result in the random setting by Dragani\'c, Glock and Krivelevich. More generally, we find long induced paths in sparse graphs that satisfy a mild upper-uniformity edge-distribution condition.Comment: 7 page

DJELOVANJE EKSPLOZIJA NA KONSTRUKCIJE

The paper describes the process of determining the blast load on structures and provides a numerical example of a fictive structure exposed to this load. The aim was to become familiar with the issue of blast load because of ever growing terrorist threat and the lack of guidelines from national and European regulations on the verification of structures exposed to explosions. The blast load was analytically determined as a pressure-time history and numerical model of the structure was created in SAP2000. The results confirm the initial assumption that it is possible with conventional software to simulate an explosion effects and give a preliminary assessment of the structure.Dana je analiza opterećenja eksplozijom na konstrukciju te numerički primjer djelovanja na fiktivnu građevinu. Cilj je bio upoznati se s fenomenom eksplozije kao opterećenja na konstrukcije uslijed sve veće terorističke prijetnje te nedostatka smjernica u nacionalnim i europskim propisima o provjeri konstrukcija izloženih djelovanju eksplozija. Analitički je određeno opterećenje eksplozijom kao vremenski zapis promjene tlaka zraka te numerički modeliranja konstrukcija i prethodno određeno opterećenje u programskom paketu SAP2000. Dobiveni rezultati potvrđuju početnu pretpostavku kako je moguće konvencionalnim softverom simulirati djelovanje eksplozije i dati preliminarnu ocjenu stanja konstrukcije

NUMMERISCHE SIMULATION DER EINWIRKUNG EINER EXPLOSION AUF ÜBERFÜHRUNGEN

Nadvožnjak nije moguće učiniti, projektiranjem i/ili izvedbom, apsolutno sigurnim na djelovanje eksplozije jer se ni sama količina eksploziva koja bi se detonirala ispod mosta u nekakvom napadu ne može odrediti s prihvatljivom vjerojatnošću. U radu je analizirano djelovanje tri količine eksploziva detonirane ispod rasponske konstrukcije nadvožnjaka. Promatrano je djelujuće opterećenje, ponašanje i oštećenje rasponskog sklopa nadvožnjaka. Zaključeno je kako sve tri količine eksploziva znatno oštećuju uobičajeni nadvožnjak te uzrokuju rušenje. Nelinearna numerička analiza nadvožnjaka provedena je koristeći hidrokod softver Ansys Autodyn.Overpasses can not be made absolutely safe to explosive action, regardless of interventions made during their design and/or realisation. This is due to the fact that the very quantity of explosive to be activated under the bridge during an attack can not be defined with an acceptable level of probability. Three quantities of explosives activated under the overpass structure are analysed. The load, behaviour, and damage to overpass superstructure are considered. It is stated in conclusion that all three quantities of explosive afflict considerable damage to usual overpasses, and cause their collapse. The nonlinear numerical analysis of the overpass was conducted using the Ansys Autodyn hydrocode software.In Übereinstimmung damit wurde die Wirkung von drei Sprengstoffmengen analysiert, die unter der Konstruktion der Überführung detonierten. Beobachtet wurden die einwirkende Belastung, das Verhalten und die Beschädigung am Überbau der Überführung. Es wurde festgestellt, dass alle drei Sprengstoffmengen eine normale Überführung erheblich beschädigen sowie den Einsturz verursachen. Die nicht lineare nummerische Analyse der Überführung wurde durch Anwendung der hidrokod Software Ansys Autodyn durchgeführt

Utjecaj vertikalne komponente potresa na AB nosače velikog raspona

Most of the previous studies in the field of earthquake engineering have neglected the effects of vertical ground motion and are usually guided by horizontal motion. The EN1998 proposes action analysis of the vertical acceleration for certain types of elements and their length and their distance from the active fault. In this paper simply supported beams with various spans, 10, 15 and 20 m, are calculated for the action of real earthquakes with different intensities. Two typical cross sections were chosen: "T" cross section and rectangular cross section. The linear and nonlinear material models were used, and all the models were calculated using rigid and elastic supports. Through the combinations of these different spans, cross sections, material models and types of the supports, the influence and importance of the vertical component of the ground motion is estimated. Based on the results obtained it was concluded that there is a need for the application of vertical acceleration in the seismic analysis of these elements.Dosadašnja su ispitivanja učinaka potresa zanemarivala vertikalno gibanje tla te se uglavnom usmjeravala prema horizontalnoj komponenti. EN1998 daje preporuku analize djelovanja vertikalnog ubrzanja za određene vrste elemenata i njihovih duljina te njihove udaljenosti od aktivnog rasjeda. U radu se analiziraju jednostavno oslonjeni nosači različitih raspona, 10, 15, 20 m te pravokutnog i "T" poprečnog presjeka. Primijenjena su dva tipa oslanjanja, kruti i elastični ležaj te dva tipa modela materijala, linearni i nelinearni. Nosači su podvrgnuti djelovanju četiri realna potresa različitog intenziteta. Na ovaj se način pratila promjena u momentima savijanja nosača u polovici raspona kako bi se vidio doprinos vertikalnog ubrzanja. Na temelju dobivenih rezultata zaključeno je kako za analizirane nosače ipak postoji potreba primjene vertikalne akceleracije prilikom seizmičke analize

REAL-TIME BRIDGE MONITORING

Mostovi su važne infrastrukturne građevine i zbog toga ih je potrebno održavati. Održavanje obuhvaća preglede i popravak uočenih oštećenja. U radu je dan pregled nekih od metoda za kontinuirano motrenje i primjeri njihove primjene na izgrađenim mostovima. Metode koriste: GPS (Global Positioning System; satelitski Sustav globalnog pozicioniranja), akcelerometre, optička vlakna, anemometre, tenzometre. Iako je postavljanje opreme za kontinuirano motrenje mostova isprva skuplje od uobičajenih metoda, ono omogućuje uvid u stanje mosta u bilo kojem trenutku te pravodobno reagiranje.Bridges are important infrastructural objects and they must be maintained. Maintenance includes inspection and repair of identified damages. Paper gives a review of several methods for real-time monitoring. Methods use: GPS (Global Positioning System), accelerometars, optical fibers, anemometers, strain gages. Although the installation of equipment for real-time monitoring is initially more expensive then for conventional methods it enables an insight into a condition of the bridge in any given time and reaction in timely manner

UDAR MOTORNOG VOZILA U STUP MOSTA

As speed limits and traffic on city roads continue to increase, collisions between road vehicles and bridge columns are becoming more common. Current regulations analyze collision with one major simplification: replacing dynamic action with the equivalent static force. In the present paper, we develop a numerical model of a typical Croatian overpass and loaded it with an equivalent static load according to the EN1991-7 and ASSHTO LRFD provisions, analyzing the differences in overpass behavior between them. We compared this to a simplified dynamic analysis, which assumed the impact forces to be impulse loads. Protection measures can be installed around bridge columns that reduce the probability of vehicle collision and open possibilities for reducing collision forces.Udar vozila u stup mosta više nije rijetkost, ponajviše zbog sve veće opterećenosti prometnica i povećanja dopuštenih brzina vozila. Problem udara obrađen je u propisima uz znatno pojednostavljenje, dinamičko djelovanje zamijenjeno je ekvivalentnim djelovanjem statičke sile. Izrađen je numerički model tipičnog mosta na hrvatskim cestama na koji je primijenjena sila udara prema EN1991-7 i ASSHTO LRFD propisima kako bi se pokazala razlika između preporučenih djelovanja. Izvedena je dodatna usporedba s pojednostavljenim dinamičkim proračunom, gdje je sila udara pretpostavljena kao impulsno opterećenje. Oko stupova mostova mogu biti postavljene zaštitne mjere koje umanjuju vjerojatnost pojave udara i omogućavaju smanjenje veličina sila korištenih u proračunu