Electrification of Airport Operations: Electric Powered Tow-Truck Utilization in Taxiing Operations

ABSTRACT Civil aviation has steadily increased over the past decades and plays an essential role in connecting people and countries across the world. According to the International Civil Aviation Organization (ICAO, 2018), passenger traffic has grown with an average of 5.4% between 1995 and 2015. ICAO estimates the demand for aviation to continue increasing by an annual rate of 4.3% until 2035 and 4.1% until 2045. Among several crucial objectives of air transportation system problems, the minimization of fuel consumption has a profound impact on both the economic viability of airline companies and the impact of air-transportation in the environment. Although aviation is not currently the leading cause of global warming, industry development, and the increase in air transportation will make it a significant factor for global warming over the coming decades. Predicting the impact of aviation on economic and environmental systems requires investigations at different stages of air transport operations. One of the strategies to reduce the fuel consumption of aviation is to optimize the fuel burn during airplane ground movement (taxiing) in airports. The main reason is that aircraft ground movement is a significant source of fuel consumption and emissions at an airport (e.g., it is estimated that aircraft burn about 7% of their fuel during this stage of the flight). Among different ways of taxiing operation in an airport, electrification of ground transportation has proven to be one of the most efficient ways which have many advantages such as reducing fuel consumption and emission of greenhouse gases with low maintenance cost. However, it should be noted that electric-powered vehicles can be a beneficial and efficient way of taxiing in airports if the electricity is clean. Clean electricity is produced from IV renewable and non-emitting sources such as wind, sun, and water. Using electric-powered vehicles in airports might not be the optimal option if the electricity is produced by burning fossil fuels like coal. Nowadays, in many provinces of Canada, the produced electricity is clean, and the government is determined to have 90% clean electricity across Canada by 2030. The presented study discusses the scheduling of aircraft towing tractors at the airport in order to minimize the fuel consumption and environmental emission of airplane engines and towing tractors. In this study, we developed a Mixed Integer-Linear Programming (MILP) model to schedule electric-powered towing vehicles (pushback Tugs) to provide taxiing services to aircraft. The proposed MILP solution enables aircraft to request a towing vehicle when it is available or perform traditional taxiing operations by using aircraft engines to minimize operating costs, which includes delay/earliness costs, fuel consumption cost, and towing cost. We concluded that the hybrid system for taxiing operation which includes both traditional engine powered solutions and the proposed electric-powered towing vehicle approaches, is the optimal solution. Through sensitivity analysis, the proposed taxiing operations planning model determines the optimum number of towing vehicles in an airport

Optimal Scheduling of Distributed Energy Resources Considering Volt-VAr Controller of PV Smart Inverters

This paper proposes an operational scheduling model of distributed energy resources (DERs) and PV smart inverters with Volt-VAr controller using an accurate AC optimal power flow (ACOPF) in an unbalanced distribution network. A mathematical mixed-integer model of local Volt-VAr droop controller of the distributed mixed-phase PV smart inverters is proposed based on the IEEE 1547-2018 standard and is incorporated in the unbalanced ACOPF, which enables effective utilization of the Volt-VAr controllers to not only alleviate voltage issues locally but also at the feeder level. The proposed model is tested on two actual snapshots of a distribution feeder in Arizona. Also, the proposed operational scheduling method considering the Volt-VAr droop controller of PV smart inverters is compared with a recent work in scheduling of the PV smart inverters. The results illustrate that the PV smart inverters dispatches obtained by the proposed model can be practically implemented by local controller of inverters.Comment: In proceedings of the 11th Bulk Power Systems Dynamics and Control Symposium (IREP 2022), July 25-30, 2022, Banff, Canad

MODEL KLINIČKOG ZAKLJUČIVANJA U PRISTUPU FEBRILNIM ZARAZNIM BOLESTIMA U SREDNJOVJEKOVNOJ PERZIJI

Reviewing ancient manuscripts of Persian medicine (PM) reveals that there have been some basic principles for decision-making in epidemic infectious diseases that existed in the past. These PM rules for clinical reasoning were applied through a personalized approach along with public health advice in such situations. Currently, the coronavirus pandemic has been the biggest problem in the world. Its mainstay of treatment is based on preventative measures and symptomatic treatments. Meanwhile, traditional medical systems for providing preventive, supportive, and rehabilitative care to patients have received more attention than before. Thus, the specific individual approach considered by PM scholars for clinical courses of epidemic infectious diseases may help shed more light on the spread of knowledge on epidemic diseases in ancient Persia.Pregledom drevnih rukopisa perzijske medicine (PM) otkriveno je da su u prošlosti postojali neki osnovni principi za donošenje odluka o epidemijskim zaraznim bolestima. Ta PM pra-vila za kliničko zaključivanje primijenjena su kroz personalizirani pristup zajedno sa savjeti-ma o javnom zdravlju u takvim situacijama. Trenutačno je pandemija koronavirusa najveći problem u svijetu. Glavni temelj liječenja koronavirusa preventivne su mjere i simptomatska obrada. U međuvremenu, tradicionalnim medicinskim sustavima za pružanje preventivne, potporne i rehabilitacijske skrbi pacijentima posvećena je veća pozornost nego prije. Prema tome, specifičan individualni pristup koji su znanstvenici PM-a razmatrali kod kliničkog tijeka epidemijskih zaraznih bolesti mogao bi pomoći u rasvjetljavanju širenja znanja o epi-demijskim bolestima u drevnoj Perziji

Human Umbilical Cord Mesenchymal Stem Cells-Derived Exosomes Can Alleviate the Proctitis Model Through TLR4/NF-Κb Pathway

Background: Proctitis is a significant concern of inflammatory bowel diseases, especially ulcerative colitis. Exosomes are a new method for treating many diseases by their immunosuppressive and tissue-repairing potential. Here, we tried Mesenchymal stem cells (MSCs)-derived Exosomes for treating the proctitis model of rats. Materials and Methods: Rats were assigned into four groups: sham, control group, rectal, and intraperitoneal exosome injection. The proctitis model was induced by rectal administration of 4% acetic acid. The exosome was derived from human MSCs isolated from human umbilical cords. After seven days, rectum samples were assessed for histopathological, IHC, and PCR analysis. Results: The histopathologic scores, collagen deposition, and the expression of NF-κB, TLR4, TNFα, IL-6, and TGFβ were decreased in intraperitoneal exosome compared to controls. The result was not promising for the rectal administration of exosomes. Conclusion: Exosomes can suppress the inflammatory response in the proctitis model and improve the rectum's healing process. Exosomes can inhabit the NF-κB/TLR4 pathway and downstream pro-inflammatory cytokines. This study implicates the therapeutic benefits of exomes in treating proctitis

Comparação da precisão de medições lineares em imagens CBCT com diferentes campos de visão

This study sought to investigate the effect of the field of view (FOV) on linear measurements of cone beam computed tomography (CBCT) images. Methods: In this in vitro study, five dry human skulls were used. After using red wax to simulate soft tissue, the skulls were scanned using Galileos CBCT scanner (Sirona, Bensheim, Germany) with exposure parameters of 85 kVp and 21 mAs and voxel size of 0.280 mm; once with FOV of 15 cm × 8 cm and once again with 15 cm × 15 cm. The measured distances were the distance between the center of the bilateral mental foramen in the axial view (MM), the distance between the alveolar crest and the mandibular inferior border in the sagittal view on the midline (CB), and the depth of the socket of the left mandibular central incisor (L1). Descriptive statistics as well as Pearson’s correlation coefficient were used for statistical analysis (α = 0.05) using SPSS software (v. 25, IBM, NY, USA). Results: The measurements obtained with small and large FOV and with the dry skull were not significantly different (p > 0.05). The measurements obtained in small FOV had excellent correlation coefficient when compared with those obtained with the dry skull, with values of 0.890 for MM, 0.954 for CB, and 0.921 for L1 (p < 0.001). The measurements in large FOV also had excellent correlation coefficient when compared with those on the dry skull, with values of 0.894 for MM, 0.949 for CB, and 0.902 for L1 (p < 0.001). Conclusion: According to our findings, linear measurements obtained by CBCT scans in small and large FOVs were not significantly different than those on dry skulls. Since the linear measurements are accurate regardless of FOV size, selection of FOV must be based on patient factors, such as area of interest and radiation dose.O objetivo do presente estudo é investigar o efeito do campo de visão (field of view – FOV) em imagens de tomografia computadorizada de feixe cônico (CBCT) na medida linear. Métodos: Neste estudo in vitro, foram utilizados cinco crânios humanos secos. Depois de usar cera vermelha para simular tecidos moles, os crânios foram escaneados usando o scanner GALILEOS CBCT (Sirona, Bensheim, Alemanha) usando parâmetros de exposição de 85 kVp e 21 mAs e o tamanho de voxel de 0,280 mm; uma vez com FOV de 15 cm × 8 cm e outra com 15 cm × 15 cm. As medidas usadas foram as distâncias entre o centro dos forames mentuais bilaterais, na visão axial (MM): a distância entre a crista alveolar e a borda inferior da mandíbula, na visão sagital na linha média (CB); e a profundidade do soquete do incisivo central da mandíbula esquerda (L1). Estatística descritiva e o coeficiente de correlação de Pearson foram utilizados para análise estatística (α = 0,05) usando o software SPSS (v. 25, IBM, NY, EUA). Resultado: As medidas obtidas com FOV pequeno e grande e com o crânio seco não foram significativamente diferentes (p > 0,05). As medidas feitas com FOV pequeno apresentaram excelente coeficiente de correlação em relação ao crânio seco, com valores de 0,890 para MM, 0,954 para CB e 0,921 para L1 (p < 0,001). As medidas feitas no FOV grande também apresentaram excelente coeficiente de correlação em relação ao crânio seco, sendo 0,894 para MM, 0,949 para CB e 0,902 para L1 (p < 0,001). Conclusão: De acordo com nossos resultados, as medidas lineares obtidas por CBCT em FOV pequenos e grandes não foram significativamente diferentes das medidas obtidas com crânios secos. Como as medições lineares são precisas, independentemente do tamanho do FOV, a seleção do FOV deve ser baseada de acordo com os fatores do paciente, como área de interesse e dose de radiação

Prevalência de osteosclerose idiopática em ossos da mandíbula: estudo de tomografia computadorizada de feixe cônico

Objective: The aim of this study is to determine the prevalence of idiopathic osteosclerosis (IO) in the mandible in an Iranian subpopulation using cone beam computed tomography (CBCT). Methods: This cross-sectional study was performed on all CBCT images obtained in 2010-2014 from the archive of Oral and Maxillofacial Radiology Department at Isfahan Dental School. Images were evaluated by two observers in identical room and monitoring conditions. IO was defined as homogenous radiopacities with no particular etiology, ranging from 2 mm to 2 cm in size. Demographic information of all patients, as well as the lesion’s number, location, border, shape, and association with adjacent teeth were recorded. Results: From 377 CBCT images, 43 images (11.4%) had at least one IO lesion. Two separate IO lesions were detected in six patients; therefore, 49 IO lesions were found in total. No gender differences were observed in IO prevalence (P = 0.806). Although most common in patients who were in their 30s, IO prevalence was not statistically different among age groups (P = 0.369). IO was most frequent in the molar region, with 63.2% of lesions. Conclusion: IO prevalence was 11.4% in the studied population and was not statistically different between age groups or sexes. Most lesions were found in the mandibular molar region.Objetivo: Este estudo busca determinar a prevalência de osteosclerose idiopática (OI) na mandíbula em uma subpopulação iraniana usando tomografia computadorizada de feixe cônico (TCFC). Métodos: Este estudo transversal foi conduzido em todas as imagens de TCFC obtidas entre 2010 e 2014 do arquivo do Departamento de Radiologia Oral e Maxilo-facial da Isfahan Dental School. As imagens foram avaliadas por dois observadores em condições iguais de ambiente e monitoramento. A OI foi definida como radiopacidades homogêneas sem causa específica, de tamanho entre 2 mm e 2 cm. As informações demográficas de todos os pacientes foram registradas, assim como o número, localização, borda e formato da lesão e sua relação com dentes adjacentes. Resultados: De 377 imagens de TCFC, 43 imagens (11,4%) tiveram pelo menos uma lesão de OI. Duas lesões individuais de OI foram detectadas em seis pacientes; assim, houve 49 lesões no total. A prevalência de OI não demonstrou preferência por gênero (P = 0,806). A OI foi mais comum em pacientes na faixa dos 30 anos de idade, mas sua prevalência não diferiu estatisticamente entre faixas etárias (P = 0,369). A região mais comum para OI foi a do molar, onde ocorreram 63,2% das lesões. Conclusão: A prevalência de OI foi de 11,4% na população estudada e não diferiu estatisticamente entre faixas etárias e sexos. A maioria das lesões foi encontrada na região do molar mandibular

Behavior-Aware Aggregation of Distributed Energy Resources for Risk-Aware Operational Scheduling of Distribution Systems

Recently there has been a considerable increase in the penetration level of distributed energy resources (DERs) due to various factors, such as the increasing affordability of these resources, the global movement towards sustainable energy, and the energy democracy movement. However, the uncertainty and variability of DERs introduce new challenges for power system operations. Advanced techniques that account for the characteristics of DERs, i.e., their intermittency and human-in-the-loop factors, are essential to improving distribution system operations. This paper proposes a behavior-aware approach to analyze and aggregate prosumers’ participation in demand response (DR) programs. A convexified AC optimal power flow (ACOPF) via a second-order cone programming (SOCP) technique is used for system scheduling with DERs. A chance-constrained framework for the system operation is constructed as an iterative two-stage algorithm that can integrate loads, DERs’ uncertainty, and SOCP-based ACOPF into one framework to manage the violation probability of the distribution system’s security limits. The benefits of the analyzed prosumers’ behaviors are shown in this paper by comparing the optimal system scheduling with socially aware and non-socially aware approaches. The case study illustrates that the socially aware approach within the chance-constrained framework can utilize up to 43% more PV generation and improve the reliability and operation of distribution systems

Prevalence and Causes of Neonatal Mortality in Hormozgan Province, Southern Iran

Infant health care should be one of the first and most important tasks of every nation and one of the main programs of any government, because children, as a vulnerable group, have a special place in health services . Based on the findings, the number of live births in 2014 and 2015 was 39627 and 41575, respectively. The number of neonatal deaths in 2014 was 12.5%̧ while it was 10.5% in 2015. The most common causes of neonatal mortality in 2014 and 2015 were respectively premature birth defects, congenital anomalies, and respiratory infections, which were similar to previous years. it is necessary to identify the preventable factors in neonatal mortality and design the necessary interventions to reduce infant mortality

Using Of Educational Movie In Teaching Preapical Bisecting Technique In Dental Students’ Isfahan University Medical Sciences

Introduction: Parallel with the progress in the educational technology, teaching methods have shifted from traditional methods to new methods. One of these methods and educational tools, in the electronic education, is educational movies. This study was done to review the effect of educational bisecting periapical radiograph technique video clip on dentistry students’ learning at Isfahan University of Medical Sciences. Methods: In this quasi-experimental study, 54 students of the 6th semester of the dentistry school of Isfahan University of Medical Sciences, who studied the course of dental radiology in the academic years 2017-2018, were included in the study. These students were randomly divided into two groups; in the first group, method of taking radiographs were taught in the field. In the second group, the teaching method was both in the field and by movie. Scores of two groups were compared for evaluate learning of the students. Data analysis was performed using descriptive statistics and independent test. Results: The mean score of dental radiography in the traditional group was 41±9/06 and in the other group was 105±16.05. The difference between the means of the two groups was significant )p>0/001,t 32.1). The average score of students' satisfaction with the quality of the educational video was 40/3±5/2. Conclusion: The results showed that educational movie with traditional methods could be an effective strategy for better learning in students