286 research outputs found

    An Optimal Coordination Framework for Connected and Automated Vehicles in two Interconnected Intersections

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    In this paper, we provide a decentralized optimal control framework for coordinating connected and automated vehicles (CAVs) in two interconnected intersections. We formulate a control problem and provide a solution that can be implemented in real time. The solution yields the optimal acceleration/deceleration of each CAV under the safety constraint at "conflict zones," where there is a chance of potential collision. Our objective is to minimize travel time for each CAV. If no such solution exists, then each CAV solves an energy-optimal control problem. We evaluate the effectiveness of the efficiency of the proposed framework through simulation.Comment: 8 pages, 5 figures, IEEE CONFERENCE ON CONTROL TECHNOLOGY AND APPLICATIONS 201

    Pediatric Elbow Fractures in a Major Trauma Center in Iran

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    Background: Elbow fractures are one of the most common traumatic fractures in the pediatric population. Since severe complications may occur, appropriate diagnosis and treatment are imperative when dealing with this type of fracture. Objectives: The aim of this study was to evaluate the epidemiology of elbow fracture in children admitted in Alzahra hospital, Isfahan, IR Iran over a one year period. Patients and Methods: During a one year period, a prospective study was conducted on 300 patients under the age of 16 who had sustained elbow fractures. Data included age, gender, mechanism of trauma, type of elbow fractures, complications, and outcomes. Results: The mean age of the patients was 8.1 ± 2.31 years old. Boys were injured 2.6 times more often than the girls. Falling was the major cause of pediatric elbow fractures (86%). Supra condylar were the most common type of fracture. There was a significant association between gender and type of injury (P < 0.01). Conclusions: Supracondylar fracture is the most common fracture type resulting from 4 - 8 year old boys’ falls. Our findings indicate the critical nature of appropriate treatment in order to prevent severe complications

    Evaluation and Importance of Trauma

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    Experimental Validation of a Real-Time Optimal Controller for Coordination of CAVs in a Multi-Lane Roundabout

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    Roundabouts in conjunction with other traffic scenarios, e.g., intersections, merging roadways, speed reduction zones, can induce congestion in a transportation network due to driver responses to various disturbances. Research efforts have shown that smoothing traffic flow and eliminating stop-and-go driving can both improve fuel efficiency of the vehicles and the throughput of a roundabout. In this paper, we validate an optimal control framework developed earlier in a multi-lane roundabout scenario using the University of Delaware's scaled smart city (UDSSC). We first provide conditions where the solution is optimal. Then, we demonstrate the feasibility of the solution using experiments at UDSSC, and show that the optimal solution completely eliminates stop-and-go driving while preserving safety.Comment: 6 Pages, 4 Figures, 1 tabl

    Methylene blue usage in the evaluation of traumatic necrosis in a rabbit liver injury model

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    BACKGROUND: In this study, the efficacy of methylene blue in the differentiation of devascularized and vital areas in a traumatic liver model in rabbits was investigated. METHODS: Twenty healthy rabbits were selected and randomly divided into two equal groups. Surgery was performed through an upper abdominal mid-line incision 5 cm in length. After induction of liver injury, diluted methylene blue was injected through the portal vein and staining onset and discoloration times were recorded. RESULTS: All 20 rabbits survived until the end of the experiment. In cases, non-perfused areas of the liver remained unstained. In control rabbits, liver parenchyma was stained homogeneously. The mean onset time of staining in normal parenchyma was 18.1±1.3 sec in cases and 17.7±1.4 sec in controls (p=NS). The mean discoloration time was 53.1±3.7 sec in cases and 53.1±3.2 sec in controls (p=NS). CONCLUSION: In major liver injuries requiring surgical intervention, methylene blue injection can be used for detection of non-perfused areas in the liver

    Evaluation of the Safe Ischemic Time of Clamping During Intermittent Pringles Maneuver in Rabbits

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    Background: The liver is the most commonly injured organ in blunt abdominal trauma. Although major hepatic bleeding may be partially controlled with portal triade clamping (the Pringle’s maneuver), continuous prolonged clamping results in liver ischemia. Objectives: The purpose of this study was to determine the safe time of Pringle maneuver based on pathologic changes of liver in rabbit models. Materials and Methods: In an experimental study, 20 New-Zealand white rabbits were selected. In laparotomy, a blunt dissector was passed through the foramen of Winslow and the hepato-duodenal ligament encircled with an umbilical tape. En masse Pringle maneuver was performed using atraumatic flexible clamps. Rabbits were divided into four groups based on Pringle maneuver time (30 minutes, 45 minutes, 60 minutes, and 75 minutes). A hepatic biopsy was performed at the beginning of operation. The degree of tissue injury was evaluated using blood markers. Results: There were five rabbits in each group. At the end of 60 minutes ischemia, only minor alterations were observed in pathological specimens. At the end of 75 minutes, hepatocyte damage and necrosis were observed. The serum levels of alanine aminotransferase (Group A: P = 0.02; Group B: P = 0.01; Group C: P = 0.0002; Group D: P = 0.01) and Aspartate aminotransferase (Group A: P = 0.03; Group B: P = 0.002; Group C: P = 0.0004; Group D: P = 0.0003) were significantly increased post-operatively. The maximum level was in the first day after operation. Conclusions: Continuous portal triade clamping (the Pringle maneuver) during liver ischemia (30 and 45 minutes) in rabbits resulted in no ischemic change. Increasing time of clamping to 30 minutes was safe in intermittent Pringle maneuver

    Evaluation of lidocaine ointment in treatment of chronic anal fissure

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    زمینه و هدف: تا چند سال اخیر درمان اصلی فیشر مزمن آنال، روشهای جراحی جهت اسفنکتروتومی لترال به روش باز یا بسته بود. در طی سال های اخیر استفاده از درمان طبی در درمان این بیماری مطرح شده است که هر یک دارای محدودیت هایی می باشد. این مطالعه با هدف مقایسه دو روش جراحی و درمان طبی لیدوکائین در درمان فیشر مزمن آنال انجام شده است. روش بررسی: در این مطالعه نیمه تجربی 180 بیمار مبتلا به فیشر مزمن آنال که با علایم بیش از 6 هفته به درمانگاه جراحی بیمارستان الزهرا(س) اصفهان مراجعه کرده بودند به روش در دسترس انتخاب شدند. پس از اخذ شرح حال از بیماران و معاینه و تایید فیشر مزمن دو روش درمان جهت بیماران توضیح داده می شد و بر اساس انتخاب ایشان بیمار در گروه یک (جراحی) و یا دو (درمان طبی با لیدوکائین) قرار می گرفت. روش درمان جراحی شامل اسفنکتروتومی لترال اسفنکتر داخلی به روش بسته بود. روش درمان طبی شامل رژیم پر فیبر، طشت آب گرم، قرص سی لاکس هر شب، قرص ناپروکسن 250 میلی گرم هر 12 ساعت و استعمال پماد لیدوکائین 5 درصد قبل از اجابت مزاج و شستشوی مداوم ناحیه مقعد در حین اجابت مزاج بود. در هر دو گروه بیماران به مدت 8 هفته پی گیری شدند. داده ها به کمک آزمون های آماری کای دو، فیشر و من ویتنی تجزیه و تحلیل گردید. یافته ها: تعداد بیمارانی که مورد عمل جراحی قرار گرفتند 100 نفر و تعداد بیمارن گروه درمان طبی 80 نفر بود. میانگین سنی بیماران گروه اول 3/4±2/36 سال و گروه دوم 1/3±3/38 سال بود (05/0P>). از نظر جنسی بین دو گروه اختلاف معنی داری وجود نداشت. .مدت علایم بیماری در گروه جراحی 5/2±1/8 هفـته و در گروه درمان طبی 1/3±9/7 هفته بود (05/0P>). در گروه جراحی عوارض پس از عمل شامل 10 مورد اکیموز پوستی (10) 2 مورد هماتوم بزرگ (2) و 10 مورد (10) بی اختیاری خفیف نسبت به باد بود. در گروه دوم هیچ عارضه ای دیده نشد. میزان بروز ترمیم زخم در گروه اول 93 و در گروه دوم 75 بود (05/0
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