Alternativna metoda za povečanje prenosnih zmogljivosti konvencionalne 110 kV linije

The purpose of this paper is to show that a significant increase in the ampacity of a 110 kV underground cable line is achievable, if a hydronic asphalt pavement system is applied along the entire line, and if the cable trench is completely filled with high thermal conductivity bedding in order to improve the conduction of heat between the line and the surface of the earth. In such a way, it would be possible to simultaneously collect and then store heat from the sun and cable line. The mutual thermal effects between the 110 kV cable line and the hydronic asphalt pavement, in the presence of solar radiation, wind-driven convection and heat emission along the earth surface, are simulated using FEM-based models for the most unfavourable summer conditions and the most common winter conditions. An adequate experimental background is also provided based on the existing measurements relevant to the thermal analysis performed. It was found that, compared to the associated base cases, the cable ampacity can be increased up to 92.3% for the most unfavourable summer conditions, and up to 60.3% for the most common winter conditions.Namen prispevka je prikazati možnost doseganja znatnega povečanja zmogljivosti 110 kV podzemnega vodnika, kadar je vzdolž celotne linije uporabljen hidronični asfalt in v kolikor je kabelski jarek popolnoma zapolnjen z visoko toplotno prevodnim ležiščem, ki izboljša prevodnost toplote med vodnikom in zemeljsko površino. Na tak način bi bilo možno hkrati zbirati in shranjevati toploto sonca in vodnika. Medsebojni toplotni učinki med 110 kV vodnikom in hidroničnim asfaltom ob prisotnosti sončnega sevanja, vetrne konvekcije in oddajanja toplote vzdolž zemeljske površine so v prispevku simulirani z uporabo modelov baziranih na MKE. Za vremenske pogoje so izbrane najbolj neugodne poletne razmere in najpogostejše zimske razmere. Zagotovljeno je ustrezno eksperimentalno ozadje na podlagi obstoječih meritev, ki se nanašajo na opravljeno toplotno analizo. Ugotovljeno je bilo, da je možno na tak način v primerjavi s trenutno izvedbo zmogljivost vodnikov za najbolj neugodne poletne razmere povečati do 92,3 %, za najpogostejše zimske razmere pa do 60,3 %

The Role of Antibiotics in Nasal Fractures after Closed Reduction

Background:. Nasal fractures represent the most common fracture in facial trauma. The role of prophylactic antibiotics in these injuries is debated, given low infection rates and demonstrated risks of antibiotics. We studied the isolated effect of prophylactic antibiotics on infection rate in patients with nasal fracture after closed reduction. Methods:. Retrospective cohort study of a prospectively maintained facial trauma database was conducted. Demographics, comorbidities, fracture classifications, and management of patients who received antibiotics at the time of closed nasal reduction were compared against those who did not receive antibiotics. Infection rates between groups were analyzed. Multivariate analysis was conducted to control for confounding variables. Qualitative analysis was performed for patients who experienced infection following nasal fracture. Results:. A total of 282 patients met inclusion criteria (n = 144, antibiotic; n = 138, nonantibiotic). Six patients experienced infection. There was no difference in infection rate between antibiotic and nonantibiotic groups (2.0% versus 2.2%; P = 0.90). On multivariate regression, antibiotics did not significantly decrease odds of infection (OR 1.7 [0.17–13.6]; P = 0.64). Moreover, patients with open nasal fractures did not have significantly higher odds of infection (OR 1.9 [0.08–20.8]; P = 0.64). Similarly, increasing severity of injury based on Rohrich classification did not significantly impact odds of infection (OR 0.68 [0.23–1.9]; P = 0.46). All six infections were managed at the bedside, with zero infections following operating room management (P = 0.32). Conclusions:. Prophylactic antibiotics do not decrease infection rates following nasal fractures managed by closed reduction. Bedside management may be a risk factor for the development of infection; however, this finding requires further evaluation