Analysis of strain distribution in overmatching V groove weld using digital image correlation

Welded joints are treated as critical sites when constructing and calculating welded structures due to inhomogeneity and anisotropy of materials at the welded joint site. Because of the change in the geometry of the elements, the welded joint is viewed as the location of the stress concentration and therefore as a place that weakens the overall load capacity of the structure. Due to this approach in the design of welded structures, practice requires that in most cases welded joints are performed with better mechanical properties compared to the base metal. A welded joint that is made so that the mechanical properties of the weld metal exceed the mechanical properties of the base metal is called the overmatching welded joint. This paper presents the measurement of the strain over the 'overmatching' welded V joint using the DIC (Digital Image Correlation) method and the analysis of the strain distribution is provided. The strain distribution obtained is interesting because it shows that in the stress concentration points the strain have almost minimal values

Improvement of the key indicators of business performance in the foundry industry

Unapređenje ključnih indikatora perofrmansi poslovanja u industriji livarstva radi dostizanja globalnih standarda procesne i resursne efikasnosti od opšteg je interesa za srpske livnice s obzirom na dokazanu polaznu hipotezu ove disertacije da su ključni indikatori performansi poslovanja srpskih livnica na nižem nivou u odnosu na ruske i evropske livnice. Doprinos ove disertacije se može posmatrati iz naučne perspektive i perspektive poslovne prakse u industriji livarstva. U naučnom smislu, doprinos disertacije se može predstaviti na sledeći način: - izvršeno je snimanje stanja u industriji livarstva u Srbiji i izvršeno je upoređivanje (benčmarking) performansi srpskih livnica s performansama evropskih, ruskih i svetskih livnica; - definisan je BSC model za livnice; - na bazi modela realizovano je i primenjeno u realnom okruženju softversko rešenje primenom modifikovanog softvera BSC DESIGNER i na bazi njega prikazan stepen ostvarenja poslovnih ciljeva u srpskim livicama; - potvrđeno je da su ključni indikatori performansi poslovanja u srpskim livnicama su na nižem nivou u odnosu na evropske i ruske livnice; - potvrđeno je da se metod vektora podrške SVM može uspešno koristiti pri unapređenju tehnoloških procesa u livnicama; - potvrđeno je da se optimizacija procesa livenja može ostvariti regresionom analizom primenjenom na odlivke otporne na habanje; - potvrđeno je da se primenom BSC metoda iskazuje efektivnost poslovnih procesa u livnicama, a na bazi toga nivo organizacionog učenja. Praktični doprinos disertaciji se odnose na: - izradu softverskog rešenja primenom modifikovanog softvera BSC DESIGNER i njegovu primenu u srpskim livicama; - unapređenjene tehnološkog procesa u livnici Guča primenom SVM metoda na primeru odlivaka otpornih na habanje; - optimizaciju procesa livenja primenom regresione analize na primeru odlivaka otpornih na habanje u livnici Guča; - unapređenje ključnih indikatora performansi poslovanja na primeru livnice Guča i povećanje efektivnost poslovnih procesa u livnici primenom BSC modela.Improvement of the key indicators of business performance in foundry industry in order to achieve global standards of process and resource efficiency is of general interest for the Serbian foundries due to the proven initial hypothesis of this dissertation that the key performance indicators of business of Serbian foundries at a lower level compared to the Russian and European foundries. The contribution of this dissertation can be seen from the scientific perspective and the perspective of business practices in the industry of casting. In scientific terms, the contribution of the dissertation can be divided as follows: - Taken of the situation in the foundry industry in Serbia the comparison has been carried out (benchmarking) between the performance of Serbian foundry with performance of European, Russian and worlds foundries; - Definition of BSC model for foundry; - Based on the model, software solution using the modified software BSC Designer was implemented and applied in a realistic environment and based on,it shows the level of achievement of the business goals of the Serbian foundries; - It is confirmed that the key performance indicators of business in Serbian foundries are at a lower level compared to European and Russian foundries; - It is confirmed that the Support Vector Machine - SVM model can be successfully used in improving of technological process in foundries; - It is confirmed that the casting process optimization is possible to achieve by regression analysis applied to a wear-resistant castings; - It is confirmed that the implementation of the BSC method shows the effectiveness of business processes in foundries and the level of oPractical contribution of dissertation is refer to: - Making software solutions using modified softwre BSC Designer and its application in the Serbian foundries; - Advancing technological processes in foundry Guca using SVM model on example of wear resistant castings; - Optimization of casting process using regression analysis on the example of wear resistant castings foundry in Guca; - Improving key indicators of business performance in the case of foundry Guca and increase the effectiveness of business processesrganizational learning on that basis

Kimura's disease in a young Balkan male

Introduction. Kimura's disease is a rare, chronic inflammatory disorder of unknown cause, mainly seen in young Asian men. To our knowledge it has not been reported previously in persons from the Balkan countries. Case report. We presented a 15-year-old male with Kimura's disease manifested as chronic left neck mass. The diagnosis was based on the histopathological findings of the excised lesion. Peripheral blood eosinophilia and raised serum Immunoglobulin E (IgE) level supported the diagnosis. Conclusion. The presented patient confirmed the fact that Kimura's disease could occur in different ethnic groups. Histopathological examination, should be performed prior to making the definitive diagnosis

Impact of COVID-19 pandemic on international trade flows in Serbia

The COVID-19 pandemic has had an impact on the global business environment, and these consequences have been heterogeneous across countries. This work contributes to the scarce literature that has been published considering the COVID-19 pandemic’s impacts on Serbian foreign trade. We analyzed the structure of Serbian imports and exports over the period 2019-2020, with a particular focus on the manufacturing sector being the most significant contributor to the Serbian international trade flows. The analysis shows that the structure of Serbian imports and exports, after the initial volatility following the outbreak of the pandemic in 2021, has stabilized and remained resilient to the impact of the COVID-19 pandemic, with very few exemptions

Strategija komunikacije za oblast klimatskih promena

Ovaj dokument predstavlja okvir za nacionalnu komuni- kaciju za oblast klimatskih promena osmišljenu sa ci- ljem da se građanima Srbije i posebnim ciljnim javnosti- ma približe tema i značaj oblasti klimatskih promena. Strategija komunikacije za oblast klimatskih promena (u daljem tekstu: Strategija komunikacije) jeste dokument na- pisan za potrebe Ministarstva zaštite životne sredine (u daljem tekstu: Ministarstvo)

Structural integrity assessment of ferrite-austenitic welded joints

Ovaj rad prikazuje uticaj prslina na integritet heterogenih feritno-austenitnih zavarenih spojeva primenom osnovnih principa mehanike loma. Sile rasta prsline su određene numerički primenom Kingove metode, dok je otpornost materijala na rast prsline određena eksperimentalno pomoću J-R krive. Da bi se odredila svojstva ovakvog zavarenog spoja, zavarene su ploče visokolegiranog austenitnog čelika i mikrolegiranog feritnog čelika. Eksperimentalno istraživanje, u kombinaciji sa numerički dobijenim rezultatima, omogućilo je procenu integriteta feritno-austenitnih zavarenih spojeva.In this paper the influence of cracks on structural integrity of heterogeneous ferrite-austenite welded joints applying the basic fracture mechanics concept was analyzed. The crack driving force was obtained numerically using King's method, while materials resistance to crack growth was determined experimentally via J-integral and was given as the J-R curve. In order to find out properties of such welded joints, plates made of high alloyed austenite steel were welded to plates made of micro alloyed ferrite steel. The experimental investigation, in combination with the numerically obtained results, enabled reliable estimation of structural integrity of ferrite-austenite welded joints

Repair welding of pressure equipment with unacceptable defects

The paper describes non-destructive testing and the repair welding technology for eliminating defects in the pressure equipment of RHE BB (Bajina Basta) (located in Serbia). The obtained results had justified the proposed technology

Repair welding of pressure equipment with unacceptable defects

The paper describes non-destructive testing and the repair welding technology for eliminating defects in the pressure equipment of RHE BB (Bajina Basta) (located in Serbia). The obtained results had justified the proposed technology

Structural integrity assessment of ferrite-austenitic welded joints

Ovaj rad prikazuje uticaj prslina na integritet heterogenih feritno-austenitnih zavarenih spojeva primenom osnovnih principa mehanike loma. Sile rasta prsline su određene numerički primenom Kingove metode, dok je otpornost materijala na rast prsline određena eksperimentalno pomoću J-R krive. Da bi se odredila svojstva ovakvog zavarenog spoja, zavarene su ploče visokolegiranog austenitnog čelika i mikrolegiranog feritnog čelika. Eksperimentalno istraživanje, u kombinaciji sa numerički dobijenim rezultatima, omogućilo je procenu integriteta feritno-austenitnih zavarenih spojeva.In this paper the influence of cracks on structural integrity of heterogeneous ferrite-austenite welded joints applying the basic fracture mechanics concept was analyzed. The crack driving force was obtained numerically using King's method, while materials resistance to crack growth was determined experimentally via J-integral and was given as the J-R curve. In order to find out properties of such welded joints, plates made of high alloyed austenite steel were welded to plates made of micro alloyed ferrite steel. The experimental investigation, in combination with the numerically obtained results, enabled reliable estimation of structural integrity of ferrite-austenite welded joints

LATE LIVER METASTASIS 20 YEARS AFTER THE INITIAL DIAGNOSIS: A CASE REPORT OF METACHRONOUS HORMONE DEPENDENT TUMORS OF BREAST AND ENDOMETRIUM

Breast cancer is the most common cancer and a significant cause of morbidity and mortality in female population worldwide. The liver is the third most common metastatic site for invasive breast malignancy besides bones, lungs and brain. Breast cancer has been linked with metachronous bone, endometrial, colon/rectal, connective tissue (sarcoma), leukemia, lung, ovary or thyroid cancer. Studies have shown an increased risk of secondary malignancies in women treated for breast malignancy in connection to adjuvant treatment in certain cases. We present a case of a 71 year old woman who was diagnosed with breast cancer 20 years ago. The primary diagnosis was invasive lobular breast cancer localized in left lower lateral quadrant. Micromorphological, histochemical and immunohistochemical analyses rendered diagnosis inconclusive due to lack of tissue so after 4 months rebiopsy was performed. Clinico-pathological correlation of the second biopsy was in favor of liver metastasis of partially hormone dependent breast cancer. Immunohistochemistry was vital for the diagnosis on the liver biopsy, in particular GATA3 positivity and vimentin negative staining which helped us exclude endometrial cancer metastasis which was diagnosed before the initial liver biopsy. GATA 3(+)/vimentin(-) panel proved to be superior to GCDFP-15 and mammaglobin in proving the breast origin of  the secondary tumor deposit.Liver metastasis from primary breast cancer can in certain cases occur many years after the initial diagnosis which shows the importance and necessity for long term follow-up of these patients, while considering the possibility of metachronous tumors as well