scholarly journals PRACTICAL ASPECTS OF MEASURING CRITICAL GAPS AND FOLLOW-UP TIMES AT MEDIAN UNCONTROLLED T-INTERSECTIONS

2021 ◽  
Vol 113 ◽  
pp. 17-28
Author(s):  
Adrian BARCHAŃSKI ◽  
Renata ŻOCHOWSKA
Keyword(s):  
Field Tests ◽  
Traffic Conditions ◽  
Essential Step ◽  
Traffic Measurements

Estimation of critical gaps and follow-up times between vehicles at uncontrolled intersections is an essential step in estimating the capacity of these objects and assessment of traffic conditions. Therefore, measurements of these parameters should be properly prepared and implemented. This paper presents issues related to the performance of field tests at median uncontrolled T-intersection. Measurements included both critical gaps and follow-up times. Based on the collected material, the authors identified problems occurring during traffic observation. Analyzed intersections were located both within and outside built-up areas. Furthermore, this article discusses the influence of selected factors on the accuracy of estimating the critical gaps and follow-up times and formulates the principles of conducting traffic measurements at selected types of intersections.

scholarly journals Arteriovenous Passage Times and Visual Field Progression in Normal Tension Glaucoma

2013 ◽  
Vol 2013 ◽  
pp. 1-6 ◽  
Author(s):  
Eva Charlotte Koch ◽  
Kay Oliver Arend ◽  
Marion Bienert ◽  
Andreas Remky ◽  
Niklas Plange
Keyword(s):  
Visual Field ◽  
Field Tests ◽  
Normal Tension Glaucoma ◽  
Retinal Blood Flow ◽  
Visual Field Progression ◽  
Confocal Scanning Laser Ophthalmoscope ◽  
Confocal Scanning ◽  
Confocal Scanning Laser ◽  
Passage Times

Purpose. Fluorescein angiographic studies revealed prolonged arteriovenous passage (AVP) times and increased fluorescein filling defects in normal tension glaucoma (NTG) compared to healthy controls. The purpose of this study was to correlate baseline AVP and fluorescein filling defects with visual field progression in patients with NTG.Patients and Methods. Patients with a follow-up period of at least 3 years and at least 4 visual field examinations were included in this retrospective study. Fluorescein angiography was performed at baseline using a confocal scanning laser ophthalmoscope (SLO, Rodenstock Instr.); fluorescein filling defects and AVP were measured by digital image analysis and dye dilution curves (25 Hz). Visual field progression was evaluated using regression analysis of the MD (Humphrey-Zeiss, SITA-24-2, MD progression per year (dB/year)). 72 patients with NTG were included, 44 patients in study 1 (fluorescein filling defects) and 28 patients in study 2 (AVP).Results. In study 1 (mean follow-up years, visual field tests), MD progression per year ( dB/year) was significantly correlated to the age (, ) but not to fluorescein filling defects, IOP, or MD at baseline. In study 2 (mean follow-up years, visual field tests), MD progression per year ( dB/year) was significantly correlated to AVP (, ) but not to age, IOP, or MD at baseline.Conclusion. Longer AVP times at baseline are correlated to visual field progression in NTG. Impaired retinal blood flow seems to be an important factor for glaucoma progression.

scholarly journals The Influence of the Carbo-Glass Geogrid-Reinforcement on the Fatigue Life of the Asphalt Pavement Structure / Wpływ Zbrojenia Siatka Weglowo–Szklana Na Trwałosc Zmeczeniowa Asfaltowej Nawierzchni Drogowej

2012 ◽  
Vol 58 (1) ◽  
pp. 97-113 ◽  
Author(s):  
J. Górszczyk ◽  
S. Gaca
Keyword(s):  
Fatigue Life ◽  
Asphalt Pavement ◽  
Field Tests ◽  
Traffic Loading ◽  
Geogrid Reinforcement ◽  
Traffic Conditions ◽  
Pavement Structure ◽  
Number Of Cycles ◽  
The One ◽  
Stress Fatigue

Abstract This paper describes the analyses of the fatigue life of the asphalt pavement reinforced with geogrid interlayer under traffic loading. Finite Element ANSYS package with using nCode applications, as well as macros specially designed in APDL programming script and VBA were used to model the considered problem. Our analysis included computation of stress, fatigue life, damage matrix and rainflow matrix. The method applied was the one of fatigue calculation: stress - number of cycles in short S-N. On the basis of the performed high cycle fatigue analysis, the influence of the location of the used geogrid and of its bond with asphalt layers on the fatigue life and the work of the asphalt pavement structure were determined. The study was carried out for three temperature seasons i.e. spring and fall (assumed as one season), winter and summer. The variability of the traffic conditions were taken into account by assuming weekly blocks of traffic loading. The calculations were made using the real values of loading measured in field tests on the German highways by means of HS-WIM weighing system. As a result of the performed tests, it was proved that the use of geogrid-reinforcement may prolong the fatigue life of the asphalt pavement. However, it is required that: the geogrid should be located in the tension zone as low as possible in the structure of the asphalt layers. Moreover, it is necessary to provide high stiffness of the bond between the geogrid and the asphalt layers.

Assessment of Pantograph Loss-of-Contact Transients: A Follow-Up

2017 ◽  
Author(s):  
Bih-Yuan Ku ◽  
Guan-Ru Chen
Keyword(s):  
Field Test ◽  
Measurement Data ◽  
Field Tests ◽  
Performance Criteria ◽  
Effective Measure ◽  
Contact Wire ◽  
Video Clips ◽  
Loss Of Contact ◽  
European Standards

In this paper we present the follow-up of our work on the assessment of pantograph arcs during loss-of-contact transients. It is not easy to accurately detect the gap between the contact strip of the pantograph and the contact wire on the fly. Instead, in the European Standards EN50119 the measurable arcs are used in the performance criteria. This paper addresses the issue of arc detection from two aspects: arc image and arc intensity. Using the arc intensity sensors and an action camera we performed two field tests to verify the speculation that arc intensity does vary in different directions. This implies the requirement of more than one sensor in the detection of arcs, and the need to combine the outputs of all sensors to obtain an effective measure of arc intensity. Both issues are addressed in this paper using video clips and measurement data conducted in a field test in Taiwan.

scholarly journals Capacities and LOS Measures of Intersections

10.29007/xp8m ◽  
2018 ◽  
Author(s):  
Saiyad Shabazahara Mukhtyarali ◽  
Laxmansinh B. Zala ◽  
Amit A. Amin
Keyword(s):  
Population Growth ◽  
Signalized Intersection ◽  
Design Parameters ◽  
Gujarat State ◽  
Design Factor ◽  
Critical Gap ◽  
Traffic Conditions ◽  
Capacity Evaluation ◽  
The World

Urbanization and industrialization has caused a drastic revolution all over the world. Intersections are crucial to street’s performance. They control a speed, safety, cost, and efficiency, making right turns the key design factor in intersections improvements and operations. In Anand city of Gujarat state, due to increasing population growth and increased traffic need Capacity Evaluation selected intersections. Borsad Chowkdi-which is highly congestible, and similarly Ganesh Chowkdi and Janta Chowkdi with similar traffic conditions has been selected. Using two methods e.g.IRC-65 Method and HCM-2000 method Capacity of two Roundabouts and One un-signalized intersection has been evaluated. IRC-65(1976) method based on the geometrics of Rounabouts and give the Capacity of entire Intersections. HCM-2000 method, Design parameters are Critical Gap and Follow up Time based on Gap Acceptance Method, give the each leg Capacity.

scholarly journals Premarital genetic investigations: effect of genetic counselling

2000 ◽  
Vol 6 (4) ◽  
pp. 652-660
Author(s):  
N. Abdel Meguid ◽  
M. S. Zaki ◽  
S. A. Hammad
Keyword(s):  
Genetic Counselling ◽  
Chromosomal Abnormalities ◽  
Genetic Disorders ◽  
Consanguineous Marriage ◽  
Research Centre ◽  
Essential Step ◽  
History Of ◽  
Normal Offspring ◽  
Changing Attitudes

Over a period of 2 years, 86 couples (172 cases) were referred to the genetics clinic of the National Research Centre for premarital genetic counselling. About 73.25% had a family history of different genetic disorders. Consanguinity was found in 86.04%. Genetic investigations revealed chromosomal abnormalities in 26 cases [15.11%]; 23 cases (13.37%) had other abnormal results. After genetic counselling, postconceptional follow-up was carried out for 30 couples; 10 of them required amniocentesis that showed abnormal fetuses in 2 mothers. Other couples had normal offspring. We conclude that premarital genetic counselling is of great use in the detection of genetic disorders and is an essential step in changing attitudes towards premarital testing and reducing consanguineous marriage

scholarly journals Imaging of Gastric Carcinomatosis

2021 ◽  
Vol 10 (22) ◽  
pp. 5294
Author(s):  
Raquel Saiz Martínez ◽  
Clarisse Dromain ◽  
Naik Vietti Violi
Keyword(s):  
Risk Factors ◽  
Gastric Cancer ◽  
Peritoneal Carcinomatosis ◽  
Imaging Techniques ◽  
Response To Treatment ◽  
Imaging Features ◽  
Future Directions ◽  
Essential Step ◽  
Complete Surgical Resection

Diagnosing the absence or presence of peritoneal carcinomatosis in patients with gastric cancer, including its extent and distribution, is an essential step in patients’ therapeutic management. Such diagnosis still remains a radiological challenge. In this article, we review the strengths and weaknesses of the different imaging techniques for the diagnosis of peritoneal carcinomatosis of gastric origin as well as the techniques’ imaging features. We also discuss the assessment of response to treatment and present recommendations for the follow-up of patients with complete surgical resection according to the presence of risk factors of recurrence, as well as discussing future directions for imaging improvement.

scholarly journals Structural Responses Data Measured in an Instrumented Flexible Pavement

2020 ◽  
Vol 9 (1) ◽  
pp. 1-13
Author(s):  
Md Rashadul Islam ◽  
Rafiqul A. Tarefder
Keyword(s):  
New Mexico ◽  
Field Tests ◽  
Flexible Pavement ◽  
Temperature Variations ◽  
Traffic Conditions ◽  
Structural Responses ◽  
Different Depths ◽  
Weather Variations ◽  
Strain Responses ◽  
Real Traffic

 This study presents and analyses the stress-strain responses data measured under real traffic conditions measured between Oct. 2012 to Oct. 2013 on an instrumented flexible pavement section on Interstate 40 (I-40) in the state of New Mexico, USA. Some weather variations data such as moisture and temperature variations at different depths of the pavement over the entire year are also discussed. The moduli of different layers determined using laboratory and field tests are also presented. It is expected that results of this study will be greatly useful to understand the behaviour of flexible pavement. The data presented in this study can be used to validate any constitutive or numerical model developed by readers.

Ocular manifestations of Parkinson disease

2020 ◽  
Vol 1 (1) ◽  
pp. 1-10
Author(s):  
Mashael Al-Namaeh
Keyword(s):  
Early Diagnosis ◽  
Neurodegenerative Disorder ◽  
Imaging Techniques ◽  
Field Tests ◽  
Ocular Manifestations ◽  
Convergence Insufficiency ◽  
Eye Movement Disorders ◽  
Rule Out

Background: Parkinson's disease (PD) is the second most common neurodegenerative disorder. We aimed to review both the disease and the drug-related ocular manifestations of PD. Methods: In this manuscript, we have reviewed and summarized existing literature on the ocular manifestations and drug-related complications of PD. We have also discussed the use of current noninvasive imaging techniques, such as optical coherence tomography (OCT), for the early diagnosis and monitoring of PD. Results: Impaired color vision, reduced stereopsis, reduced contrast sensitivity, pupillary abnormalities, eye movement disorders, convergence insufficiency, dry eye syndrome, glaucoma, visual dysfunctions, retinal abnormalities, and drug-related side effects were among the listed ocular manifestations of PD. There is a large knowledge gap regarding the type of glaucoma affecting PD patients—whether it is open-angle or other types. Further case studies and long-term follow-ups during PD progression are necessary to fill this gap. Patient compliance with follow-up visits for more visual field tests and OCT during PD progression may become problematic when dementia and cognitive impairment occur. Conclusions: There is a general need for clinicians to perform further tests and more visual examinations to rule out ocular manifestations. Furthermore, additional clinical trials are needed to further evaluate the use of different types of OCT findings as biomarkers of PD progression. This would aid in early diagnosis and in delaying disease progression, if treated promptly.

Implantation of XEN After Failed Trabeculectomy: an Efficient Therapy?

2021 ◽  
Author(s):  
Caroline Bormann ◽  
Manuela Schmidt ◽  
Catharina Busch ◽  
Matus Rehak ◽  
Christian Thomas Scharenberg ◽  
...  
Keyword(s):  
Visual Acuity ◽  
Standard Procedure ◽  
Field Tests ◽  
Glaucoma Surgery ◽  
Corrected Visual Acuity ◽  
Ahmed Valve ◽  
Long Time ◽  
The Mean ◽  
Valve Implantation

Abstract Background Trabeculectomy (TE) has been the standard procedure in glaucoma surgery for a long time. This study examined the efficacy and safety profile of XEN45 Gel Stent (XEN) after failed and/or scarred trabeculectomy. Material and Methods We analysed all files of patients, who received a XEN after insufficient TE and examined changes in intraocular pressure (IOP), IOP-lowering medication, best corrected visual acuity, visual field tests as well as the intra- and postoperative complications recorded within a 12-month follow-up period. Results 31 eyes of 28 patients were analysed in our study (mean age: 66,2 ± 13,4 years; 39% female; 48% right eye; mean follow-up after TE: 70,3 ± 64,9 months). The mean IOP decreased from 23,5 ± 6,5 to 18,0 ± 5,3 mmHg (− 23,5% compared to baseline-IOP; p = 0,01) while the mean IOP-lowering medication could be reduced from 2,8 ± 1,1 to 1,1 ± 1,5 (p < 0,01) 12 months after XEN-implantation. The mean visual acuity did not change significantly (pre-op: 0,5 ± 0,6 logMAR; 12 months post-op: 0,5 ± 0,6 logMAR). The most common complications postoperatively were choroideal detachment due to postoperative hypotony in 4 eyes (13%), a needling procedure in 9 eyes (29%), a Re-XEN-Implantation in 4 eyes (13%), an open revision of the conjunctiva in 3 eyes (10%), and a Re-TE in 1 eye (3%) as well as an Ahmed-Valve implantation in 2 eyes (6%). Overall, neither needling procedure nor further glaucoma surgery was necessary in 19 eyes (61%). In 10 of 22 evaluable eyes (45%) an IOP reduction of > 20% was achieved 12 months after XEN implantation. Conclusion XEN could be an effective method to reduce IOP after failed TE. The rate of complications seems to be low and the rate of needling procedures and/or revisions is acceptable.

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