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Deadlock-free Supervisor Design for Robotic Manufacturing Cells With Uncontrollable and Unobservable Events 被引量:4
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作者 Bo Huang MengChu Zhou +2 位作者 Cong Wang Abdullah Abusorrah Yusuf Al-Turki 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2021年第3期597-605,共9页
In this paper,a deadlock prevention policy for robotic manufacturing cells with uncontrollable and unobservable events is proposed based on a Petri net formalism.First,a Petri net for the deadlock control of such syst... In this paper,a deadlock prevention policy for robotic manufacturing cells with uncontrollable and unobservable events is proposed based on a Petri net formalism.First,a Petri net for the deadlock control of such systems is defined.Its admissible markings and first-met inadmissible markings(FIMs)are introduced.Next,place invariants are designed via an integer linear program(ILP)to survive all admissible markings and prohibit all FIMs,keeping the underlying system from reaching deadlocks,livelocks,bad markings,and the markings that may evolve into them by firing uncontrollable transitions.ILP also ensures that the obtained deadlock-free supervisor does not observe any unobservable transition.In addition,the supervisor is guaranteed to be admissible and structurally minimal in terms of both control places and added arcs.The condition under which the supervisor is maximally permissive in behavior is given.Finally,experimental results with the proposed method and existing ones are given to show its effectiveness. 展开更多
关键词 Deadlock prevention Petri nets robotic manufacturing cells structure-minimized supervisor supervisory control uncontrollability unobservability
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Community Knowledge about Bleeding Control in Jazan, KSA: Is There a Need for First Aid Educational Programs
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作者 Md Mazharul Hoque Hamoud Yahya Alsuriha +10 位作者 Mohamed E. Moukhyer Bahja Siddig Mohamed Mubarak Almaki Amna Moukhyer Fawaz Yahya Masswadi Mofareh Salman Harubi Elias Yosef Modabish Talal Omar Khasawi Yaser Mohammed Hantool Mohammed Awaji Mohammed Madkhali Aziza Mukhayer 《Journal of Biosciences and Medicines》 2024年第6期64-84,共21页
The current study aimed to evaluate the first aid knowledge and general awareness of bleeding control, and their relations with different variables among the population of Jazan City, Saudi Arabia, in 2023. A cross-se... The current study aimed to evaluate the first aid knowledge and general awareness of bleeding control, and their relations with different variables among the population of Jazan City, Saudi Arabia, in 2023. A cross-sectional study was conducted in Jazan City, Saudi Arabia between April 2023 and May 2023. Participants, >13 years old, living in Jazan City, were self-enrolled. Data collection was carried out by distributing a self-reported online survey questionnaire via email and social media apps. A validated, pretested online self-report questionnaire was used for data collection, with data analysis performed using (MS) Excel 2022 and SPSS version 26. A Chi-square test was used to determine the association of sociodemographic variables and Bleeding Control (BC) knowledge with, significance set at p < 0.05. A total of 250 participants completed the questionnaire, predominantly aged between 16 - 25 years, with 152 (60.8%) being male, and about 90% being Saudi citizens. Only 53 (21.2%) participated in previous first aid training concentrating on bleeding control. Only 76 (30.4%) of participants had good knowledge, while 131 (52.4%) exhibited positive attitude towards BC first aid. There were no statistically significant associations between BC knowledge and age, gender, occupation, nationality, and education. However, a significant association was observed between previous BC training and knowledge (Chi-test = 40.373, d.f = 1, p = 0.000) at p < 0.05. Conclusion: The prevalence of poor knowledge of bleeding control among community members in Jazan City was high. The findings of this study should be carefully considered by various healthcare organizations to implement educational first-aid programs and activities aimed at enhancing community awareness and knowledge of bleeding control. 展开更多
关键词 INJURY Uncontrolled Bleeding First Aid Knowledge ATTITUDE Jazan City
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Dataset of Large Gathering Images for Person Identification and Tracking
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作者 Adnan Nadeem Amir Mehmood +7 位作者 Kashif Rizwan Muhammad Ashraf Nauman Qadeer Ali Alzahrani Qammer H.Abbasi Fazal Noor Majed Alhaisoni Nadeem Mahmood 《Computers, Materials & Continua》 SCIE EI 2023年第3期6065-6080,共16页
This paper presents a large gathering dataset of images extracted from publicly filmed videos by 24 cameras installed on the premises of Masjid Al-Nabvi,Madinah,Saudi Arabia.This dataset consists of raw and processed ... This paper presents a large gathering dataset of images extracted from publicly filmed videos by 24 cameras installed on the premises of Masjid Al-Nabvi,Madinah,Saudi Arabia.This dataset consists of raw and processed images reflecting a highly challenging and unconstraint environment.The methodology for building the dataset consists of four core phases;that include acquisition of videos,extraction of frames,localization of face regions,and cropping and resizing of detected face regions.The raw images in the dataset consist of a total of 4613 frames obtained fromvideo sequences.The processed images in the dataset consist of the face regions of 250 persons extracted from raw data images to ensure the authenticity of the presented data.The dataset further consists of 8 images corresponding to each of the 250 subjects(persons)for a total of 2000 images.It portrays a highly unconstrained and challenging environment with human faces of varying sizes and pixel quality(resolution).Since the face regions in video sequences are severely degraded due to various unavoidable factors,it can be used as a benchmark to test and evaluate face detection and recognition algorithms for research purposes.We have also gathered and displayed records of the presence of subjects who appear in presented frames;in a temporal context.This can also be used as a temporal benchmark for tracking,finding persons,activity monitoring,and crowd counting in large crowd scenarios. 展开更多
关键词 Large crowd gatherings a dataset of large crowd images highly uncontrolled environment tracking missing persons face recognition activity monitoring
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Synthesis of Petri net supervisors enforcing general constraints 被引量:6
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作者 ZHANG Yao-yao YAN Gang-feng 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第4期623-628,共6页
This paper deals with the synthesis of Petri net supervisor enforcing the more expressive constraints including marking terms, firing vector terms and Parikh vector terms. The method is developed to handle uncontrolla... This paper deals with the synthesis of Petri net supervisor enforcing the more expressive constraints including marking terms, firing vector terms and Parikh vector terms. The method is developed to handle uncontrollable and unobservable transitions existing in the constraints. The “greater-than or equal” general constraints can also be transformed into “less-than or equal” Parikh constraints. An example is analyzed to show how the problem is solved. General constraint is first transformed into Parikh vector constraints, and Matrix-Transformation is proposed to obtain the admissible constraints without uncontrollable and unobservable transitions. Then the supervisor can be constructed based on constraints only consisting of Parikh vector terms. The method is proved to be more concise and effective than the method presented by Iordache and Moody especially when applied to large scale systems. 展开更多
关键词 Petri net Supervisor control Parikh vector uncontrollable Unobservable
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Contained local compression on peri-ascending aortic area for postoperative bleeding control:a case report 被引量:1
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作者 Su Young Yoon Si-Wook Kim +1 位作者 Dohun Kim Jong-Myeon Hong 《The Journal of Biomedical Research》 CAS CSCD 2021年第1期72-74,共3页
After type A acute aortic dissection(AAD)repair or modified Bentall procedure,uncontrollable bleeding from the anastomotic sites of the fragile dissected tissues or aortic root area is a critical situation to a cardia... After type A acute aortic dissection(AAD)repair or modified Bentall procedure,uncontrollable bleeding from the anastomotic sites of the fragile dissected tissues or aortic root area is a critical situation to a cardiac surgeon.For postoperative care,lots of blood transfusion with strict monitoring on the patient all night and subsequent reoperation for the bleeding control is usually needed.We managed to make contained local compression of upper half of the heart,from upper part of the right ventricle to just above the innominate vein,using bovine pericardium with closing both sides of transverse sinus in two cases of uncontrolled postoperative bleeding(bleeding from distal anastomotic site in type-A AAD and valve sitting site in modified Bentall procedure).Even though reoperations for the removal of packed gauges were done in both cases 2 days later,postoperative courses at intensive care unit were very smooth with little need for transfusion.This kind of contained local compression trial could be a useful strategy for dealing with the malignant uncontrollable bleeding from the fragile aortic tissue or root area after acute dissection or aortic root repair. 展开更多
关键词 uncontrollable bleeding contained local compression aortic dissection aortic root repair
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Chaotic motions of the L-mode to H-mode transition model in tokamak
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作者 陈芳启 周良强 +1 位作者 王霞 陈予恕 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2009年第7期811-820,共10页
The chaotic dynamics of the transport equation for the L-mode to H-mode near the plasma in a tokamak is studied in detail with the Melnikov method. The transport equations represent a system with external and parametr... The chaotic dynamics of the transport equation for the L-mode to H-mode near the plasma in a tokamak is studied in detail with the Melnikov method. The transport equations represent a system with external and parametric excitation. The critical curves separating the chaotic regions and nonchaotic regions are presented for the system with periodically external excitation and linear parametric excitation, or cubic parametric excitation, respectively. The results obtained here show that there exist uncontrollable regions in which chaos always take place via heteroclinic bifurcation for the system with linear or cubic parametric excitation. Especially, there exists a controllable frequency, excited at which chaos does not occur via homoclinic bifurcation no matter how large the excitation amplitude is for the system with cubic parametric excitation. Some complicated dynamical behaviors are obtained for this class of systems. 展开更多
关键词 transitions in tokamak CHAOS Melnikov method uncontrollable regions controllable frequency
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DOE在SMT新产品导入中的效应及案例分析 被引量:1
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作者 杨根林 《现代表面贴装资讯》 2013年第1期37-48,共12页
引言 电子产品的SMT新品导入及生产过程中,必然会遇到产品的结构设计、各种新型制程工艺、特殊或非标元器件、相关的辅材导入等验证要求,以及生产制程参数优化、产品缺陷分析与改善等问题。为了搞好相关验证并解决以上问题,从而获... 引言 电子产品的SMT新品导入及生产过程中,必然会遇到产品的结构设计、各种新型制程工艺、特殊或非标元器件、相关的辅材导入等验证要求,以及生产制程参数优化、产品缺陷分析与改善等问题。为了搞好相关验证并解决以上问题,从而获得恰当的制程工艺参数及产品品质, 展开更多
关键词 实验设计(DoE) 新产品导入(NPI) 实验因子(Experiment Factor) 稳健性参数设计(Robust Parameter Design) 可控因子(Controllable Factor) 不可控因子(uncontrollable Factor) 信号因子(Signal Factor) M㈣tab统计方法(Minitab Statistical Method) 焊点可靠性(SOIder Joint Reliability)
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Adaptive practical output tracking of a class of nonlinear systems
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作者 QiangdeWANG YuanweiJING 《控制理论与应用(英文版)》 EI 2004年第2期117-120,共4页
Focus is laid on the adaptive practical output-tracking problem of a class of nonlinear systems with high-order lower-triangular structure and uncontrollable unstable linearization. Using the modified adaptive additio... Focus is laid on the adaptive practical output-tracking problem of a class of nonlinear systems with high-order lower-triangular structure and uncontrollable unstable linearization. Using the modified adaptive addition of a power integrator technique as a basic tool, a new smooth adaptive state feedback controller is designed. This controller can ensure all signals of the closed-loop systems are globally bounded and output tracking error is arbitrary small. 展开更多
关键词 Adaptive practical output tracking Adaptive smooth state feedback uncontrollable unstable linearization
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Cancer,Mankind’s Challenge
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作者 Ying-Yu Cui 《Current Cancer Reports》 2019年第1期1-5,共5页
Cancer, or malignant tumour, is a group of diseases defined by the uncontrollable growth of the transformed cells, and their capabilities of invasion into surrounding healthy tissues and metastasis to remote sites in ... Cancer, or malignant tumour, is a group of diseases defined by the uncontrollable growth of the transformed cells, and their capabilities of invasion into surrounding healthy tissues and metastasis to remote sites in the body of organisms[1, 2]. 展开更多
关键词 CANCER uncontrollable GROWTH transformed CELLS
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Efficacy and economic analysis of Ex- PRESS implantation versus trabeculectomy in uncontrolled glaucoma: a systematic review and Meta-analysis 被引量:5
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作者 Ling Wang Fang Sha +4 位作者 Da-Dong Guo Hong-Sheng Bi Jun-Kang Si Yu-Xiang Du Kai Tang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2016年第1期124-131,共8页
AIM:To systematically review the current evidence based on the efficacy and cost of Ex-PRESS implantation and trabeculectomy(Trab)for uncontrolled glaucoma.·METHODS:Clinical trials were identified by electron... AIM:To systematically review the current evidence based on the efficacy and cost of Ex-PRESS implantation and trabeculectomy(Trab)for uncontrolled glaucoma.·METHODS:Clinical trials were identified by electronic databases(Pub Med,EMBASE,ISI Web of science and Cochrane library),and data,such as intraocular pressure(IOP),the complete and qualified success rate,the postoperative complications and the cost,were exacted from these relevant studies.Weighted mean difference(WMD),odds ratio(OR)and 95%confidence intervals(CIs)were calculated and were pooled using a randomeffects model.·RESULTS:Eleven relevant publications and two abstracts met the inclusion criteria.The efficacy of ExPRESS was similar to that of Trab in the percentage of IOP reduction(IOPR%)at 1,2y(WMD:-2.01;95%CI:-7.92-3.90;=0.50 and WMD:2.89;95%CI:-8.05-13.83;=0.60,respectively).Ex-PRESS possessed a significant higher complete and qualified success rate(OR:1.59;95%CI:1.07-2.35;=0.02 and OR:1.74;95%CI:1.06-2.86;=0.03,respectively).Moreover,Ex-PRESS exerted a significantly lower frequency of hypotony and hyphema than Trab(OR:0.39;95%CI:0.21-0.72;=0.003 and OR:0.27;95%CI:0.10-0.69;=0.003,respectively).However,there was no consistent result on the cost between the two groups according to the previous three studies.·C ONCLUSION:Both Trab and Ex-PRESS have equivalent efficacy in lowering IOP,yet Ex-PRESS had a lower risk of hypotony and hyphema than Trab.Nevertheless,whether the cost of Ex-PRESS was less than that of Trab should be further investigated to ensure evidence-based conclusion in the long run. 展开更多
关键词 Ex-PRESS implantation TRABECULECTOMY uncontrolled glaucoma systematic review META-ANALYSIS
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Factors associated with intensification of antihypertensive drug therapy in patients with poorly controlled hypertension 被引量:2
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作者 Olga Siga Barbara Wizner +2 位作者 Barbara Gryglewska Jolanta Walczewska Tomasz Grodzicki 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2019年第1期19-26,共8页
Objective To assess antihypertensive management of older patients with poor blood pressure(BP)control.Methods Physicians,voluntary participating in the study,included six consecutive hypertensive patients during routi... Objective To assess antihypertensive management of older patients with poor blood pressure(BP)control.Methods Physicians,voluntary participating in the study,included six consecutive hypertensive patients during routine visits.Hypertension had to have been previously recognized and averaged office BP was>140 and/or>90 mmHg in spite of>6 weeks of antihypertensive therapy.The physicians completed a questionnaire on patients'history of cardiovascular(CV)risk factors,comorbidities,home BP monitoring,anthropometric data and the pharmacotherapy.Results Mean age of the 6462 patients was 61 years,7%were>80 years,51%were female.Mean士SD office BP values were 158士13/92土10 mmHg.The most commonly prescribed antihypertensive drugs were:diuretics(67%),ACE inhibitors(64%),calcium channel blockers(58%)and卩-blockers(54%),and their use increased with age.On monotherapy or dual therapy,43%of the patients and 40%had their latest treatment modification within six months.Home BP monitoring was a factor that accelerated the modification of the therapy.Older patients had to have less chance on faster modification of antihypertensive therapy in spite of presence of diabetes and higher systolic BP.Conclusions Our study suggests that a large number of outpatients with poor BP control receive suboptimal antihypertensive therapy,especially in primary care.In older patients,higher BP values in the office settings are more frequently accepted by physicians even in case of higher CV risk.Regular home BP monitoring hastens the decision to intensify of antihypertensive treatment. 展开更多
关键词 ANTIHYPERTENSIVE THERAPY COMORBIDITIES Modification of THERAPY Older PATIENTS Uncontrolled HYPERTENSION
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Measurement of the Effective Dose Radiation at Radiology Departments of Some Hospitals in Duhok Governorate 被引量:1
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作者 Dindar S. Bari Pshtiwan M. Amin Nawzad A. Abdulkareem 《Journal of Modern Physics》 2015年第5期566-572,共7页
During operating of the X-ray machines, if the protection of X-ray rooms is insufficient, not only the patient but also clinical staffs as well as public are exposed to high X-ray dosage and they are affected from X-r... During operating of the X-ray machines, if the protection of X-ray rooms is insufficient, not only the patient but also clinical staffs as well as public are exposed to high X-ray dosage and they are affected from X-ray related to the dose level. In the present survey, by testing the radiological leakage and scatter from X-rays machines in radiology departments of 7 randomly selected hospitals in Duhok governorate, the effects dose of X-ray to the both control panel area and the patients waiting or visiting area who are located near the radiography room, were measured. The dose was recorded for a range of peak kilovoltage (kVp) and mAs values to find efficiency of shielding materials (barriers) of radiography rooms for different X-rays level. The measurements were performed at one meter above the ground surface which was the same height of X-rays tube by using Gamma Scout dosimeter. From the measurement results, it was seen that the most hospitals barriers (doors and walls) were not appropriate to the standards except 2 hospitals. The maximum effective doses were measured in uncontrolled area of Khazer hospital which was 82.48 ± 0.73 mSv&middot;yr-1 that was much more than the reference dose limits and in controlled area of Haval Banda Zaroka hospital which was 12.98 ± 0.16 mSv&middot;yr-1. In result, the knowledge about the radiation dose affecting the radiologists and public in the selected hospitals was obtained, and by informing the radiologists and the hospitals managements, the necessary regulations would be planned. 展开更多
关键词 RADIATION DOSE LEAKAGE RADIATION RADIATION Protection DIAGNOSTIC X-RAY X-RAY ROOM Duhok Hospitals Controlled and Uncontrolled Areas
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Psychological flexibility, occupational burnout and eating behavior among working women 被引量:1
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作者 Nina Nevanpera Raimo Lappalainen +3 位作者 Eeva Kuosma Leila Hopsu Jukka Uitti Jaana Laitinen 《Open Journal of Preventive Medicine》 2013年第4期355-361,共7页
Background: Occupational burnout is associated with diminished psychological flexibility and higher emotional (EE) and uncontrolled eating (UE). Psychological flexibility could be a mediating factor between burnout an... Background: Occupational burnout is associated with diminished psychological flexibility and higher emotional (EE) and uncontrolled eating (UE). Psychological flexibility could be a mediating factor between burnout and eating behaviour. Objectives: To investigate differences in eating behaviour between those with different levels of psychological flexibility, and the association of the interaction between psychological flexibility and occupational burnout with eating behaviour. Design: The participants were working women (n = 263), who took part in the randomized controlled health intervention trial. Analyses were performed in a cross-sectional setting at baseline. Methods: Eating behaviour was measured using the Three Factor Eating Behaviour Questionnaire-18 [which evaluates EE, UE and cognitive restraint (CR)], psychological flexibility using Acceptance and Action Questionnaire-II and occupational burnout using Bergen Burnout Indicator-15. Participants were divided into four groups based on the quartile points of psychological flexibility. Results: The EE of those who were inflexible was higher than that of those whose flexibility was high moderate (p = 0.013) and who were flexible (p = 0.001). The UE of those who were inflexible was higher than the UE in the other groups with higher flexibility [low moderate (p = 0.034), high moderate (p een occupational burnout and EE and UE. Multivariate analysis of variances revealed that the combination of psychological flexibility and burnout had a stronger association with the variances of EE and UE than psychological flexibility alone. Conclusions: Persons who are psychologically inflexible have higher EE and UE. Future studies should investigate if increasing psychological flexibility helps decrease EE and UE. 展开更多
关键词 Psychological Flexibility Occupational Burnout Eating Behavior Emotional Eating Uncontrolled Eating Cognitive Restraint
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Analysis of occupation time of vehicles at urban unsignalized intersections in non-lane-based mixed traffic conditions
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作者 Gowri Asaithambi Chepuru Anuroop 《Journal of Modern Transportation》 2016年第4期304-313,共10页
In India, traffic flow on roads is highly mixed in nature with wide variations in the static and dynamic characteristics of vehicles. At unsignalized intersections, vehicles generally do not follow lane discipline and... In India, traffic flow on roads is highly mixed in nature with wide variations in the static and dynamic characteristics of vehicles. At unsignalized intersections, vehicles generally do not follow lane discipline and ignore the rules of priority. Drivers generally become more aggressive and tend to cross the uncontrolled intersections without considering the conflicting traffic. All these conditions cause a very complex traffic situation at unsignal- ized intersections which have a great impact on the capacity and performance of traffic intersections. A new method called additive conflict flow (ACF) method is suitable to determine the capacity of unsignalized inter- sections in non-lane-based mixed traffic conditions as prevailing in India. Occupation time is the key parameter for ACF method, which is defined as the time spent by a vehicle in the conflict area at the intersection. Data for this study were collected at two three-legged unsignalized intersections (one is uncontrolled and other one is semi- controlled) in Mangalore city, India using video-graphic technique during peak periods on three consecutive week days. The occupation time of vehicles at these intersections were studied and compared. The data on conflicting traffic volume and occupation time by each subject vehicle at the conflict area were extracted from the videos using image processing software. The subject vehicles were divided into three categories: two wheelers,cars, and auto-rickshaws. Mathematical relationships were developed to relate the occupation time of different cate- gories of vehicles with the conflicting flow of vehicles for various movements at both the intersections. It was found that occupation time increases with the increasing con- flicting traffic and observed to be higher at the uncontrolled intersection compared to the semicontrolled intersec- tion. The segregated turning movements and the presence of mini roundabout at the semicontrolled intersection reduces the conflicts of vehicular movements, which ulti- mately reduces the occupation time. The proposed methodology will be useful to determine the occupation time for various movements at unsignalized intersections. The models developed in the study can be used by practitioners and traffic engineers to estimate the capacity of unsignalized intersections in non-lane-based discipline and mixed traffic conditions. 展开更多
关键词 Occupation time Conflicting flow Unsignalized intersection Conflict area Mixed traffic Uncontrolled intersection Semicontrolled intersection
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The Impact of Some Uncontrolled Landfill Sites on the Ecosystems of Surrounding Areas of Eastern and Western Parts of Georgia
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作者 Nugzar Buachidze Khatuna Chikviladze +2 位作者 Gulchina Kuchava Ekaterina Shubladze George Kordzakhia 《Open Journal of Ecology》 2019年第2期25-33,共9页
The most visible uncontrolled landfill sites were selected in the western and eastern parts of the territory of Georgia. Particularly, in eastern Georgia the regions of Mtskheta-Mtianeti and Kvemo Kartli have been res... The most visible uncontrolled landfill sites were selected in the western and eastern parts of the territory of Georgia. Particularly, in eastern Georgia the regions of Mtskheta-Mtianeti and Kvemo Kartli have been researched;and in western Georgia Imereti and Samtskhe-Javakheti correspondingly. Both chemical and microbiological analyses were conducted in the samples taken from their adjacent territories. In case the landfill site is located near the river, during field works using portable equipment main physical-chemical indicators of surface waters were determined. After processing of the obtained results the corresponding estimations were provided. The risks due to the environmental pollution and negative impacts on population health were assessed. 展开更多
关键词 Pollution Waste Management HEAVY Metals Uncontrolled LANDFILLS Maximum Permissible CONCENTRATIONS
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Environmental Impact of Casablanca Landfill on Groundwater Quality, Morocco
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作者 Driss Smahi Ahmed Fekri Ouafa El Hammoumi 《International Journal of Geosciences》 2013年第1期202-211,共10页
The Casablanca landfill is one among many uncontrolled dumping sites in Morocco with no bottom liner. About 4000 tons/day of solid wastes from mixed urban and industrial origins are placed directly on the fifteen old ... The Casablanca landfill is one among many uncontrolled dumping sites in Morocco with no bottom liner. About 4000 tons/day of solid wastes from mixed urban and industrial origins are placed directly on the fifteen old sandstone quarries. At the site of this landfill, the groundwaters circulate deeply (10 m) in the fractured aquiferous quartzites, the site has never been sealed before its opening. The aim of this study is the characterization the groundwater quality around the landfill, to delimit the contaminated zone and the factors controlling the extent of groundwater contamination. To evaluate groundwater pollution due to this landfill, piezometric level and geochemical analyses have been carried out on 19 wells. The results of geochemical analyses show an important qualitative degradation of the groundwater, especially in the parts situated in the down gradient area and in direct proximity to the landfill. In these polluted zones, we have observed the following values: higher than 11 mS/cm in electric conductivity, 1400 mg/L in bicarbonates, 275 mg/L in chemical oxygen demand, 2616 and 100 mg/L respectively in chlorides and sulfate, 269.5 mg/L in nitrates, 50 - 100 mg/L in cadmium, and 40 - 230 μg/L in chromium. These concentrations widely exceed the standard values for potable and irrigation water. Several determining factors in the evolution of groundwater contamination have been highlighted, such as: depth of the water table, permeability of unsaturated zone and lineaments, effective infiltration, absence of a system for leachate drainage. So, to reduce the pollution risks of the groundwater, it is necessary to set a system of collection, drainage and treatment of landfill leachates and to emplace an impermeable surface at the site of landfill, in order to limit the infiltration of leachate. 展开更多
关键词 GROUNDWATER POLLUTION LANDFILL LEACHATE Uncontrolled LANDFILL LINEAMENT Morocco
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Prevalence of Chronic Kidney Disease in Patients with Cardiovascular Disease
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作者 Said S. Khamis Ahmed M. Zahran +2 位作者 Nagwa N. Hegazy Heba E. Kasem Hayam K. El-Fiky 《Open Journal of Nephrology》 2020年第3期227-240,共14页
<strong>Background:</strong> Chronic kidney disease (CKD) is a worldwide public health alarming problem. Although both heart and kidneys are separated by a quite distance within the body and they perform v... <strong>Background:</strong> Chronic kidney disease (CKD) is a worldwide public health alarming problem. Although both heart and kidneys are separated by a quite distance within the body and they perform varied functions, there is a close physiological relationship between them. The diseases in the kidneys can trigger a disease in the heart and vice versa. High blood pressure is the most significant risk factor for the development and progression of chronic kidney disease (CKD). Lowering blood pressure is a goal to prevent CKD progress. Chronic abnormalities in cardiac function (e.g., chronic congestive heart failure) causing, chronic kidney disease and anemia appear to act together in a vicious circle in which each condition causes or exacerbates the other progressive chronic kidney disease. <strong>Objective:</strong> To assess the prevalence of chronic kidney disease in patients with cardiovascular disease at Shebin El-Kom Teaching Hospital and Menoufia University Hospital Cardiology Outpatient Clinic, Menoufia Governorate, Egypt. <strong>Methods:</strong> This is a cross-sectional study that was conducted in Shebin El-Kom Teaching Hospital Cardiology Outpatient Clinic, Menoufia University Cardiology Outpatient Clinic from April 2019 to July 2019. This study included 200 patients with cardiovascular disease or hypertension for more than 6 months. All patients were subjected to detailed history taking, clinical examination, laboratory investigation, echo and abdominal ultrasound. <strong>Results:</strong> This study included 200 patients with cardiovascular disease or hypertension for more than 6 months, which showed that: 63 (31.5%) were diagnosed as chronic kidney disease, 24 (38%) known to be CKD, 39 (62%) not known diagnosed in our study. Uncontrolled hypertension, congestive heart failure, diuretics and ACEI or ARBS with diuretics together are significant risk factors for renal impairment;uncontrolled hypertension and diuretics are the most predictors for renal impairment. <strong>Conclusion:</strong> Uncontrolled hypertension is the most preventable cause of renal impairment;RAAS not cause renal impairment but lead to decreased GFR in CKD patients. We should be careful with ACEI or ARBS with diuretics or diuretics only and control congestive heart disease to avoid kidney injury and chronic cardiorenal. 展开更多
关键词 Uncontrolled Hypertension Congestive Heart Failure Chronic Kidney Disease DIURETICS ACEI or ARBS
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Subsoil Natural Physico-chemical Reactor: The Property of Deep Abiogenic Methane-Containing High-Thermobaric Fluid to Form Coal Seams
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作者 J.M.Svoren 《Journal of Geological Resource and Engineering》 2021年第1期25-28,共4页
For the first time,the property of deep abiogenic methane-containing high-thermobaric fluid to decompose organic residues in the Earth’s crust and form coal seams was established.
关键词 Abiogenic methane-containing high-thermobaric fluid coal seams organic residues uncontrolled natural physicochemical processes mass spectrometric research method
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Gap acceptance behavior of drivers at uncontrolled T-intersections under mixed traffic conditions
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作者 Manish Dutta Mokaddes Ali Ahmed 《Journal of Modern Transportation》 2018年第2期119-132,共14页
Explicit traffic control measures are absent in uncontrolled intersections which make them susceptible to frequent conflicts and resulting collisions between vehicles. In developing countries like India, drivers at su... Explicit traffic control measures are absent in uncontrolled intersections which make them susceptible to frequent conflicts and resulting collisions between vehicles. In developing countries like India, drivers at such intersections do not yield to higher priority movements which cause more crashes between vehicles. The objective of this study is to analyze and model the gap acceptance behavior of minor street drivers at uncontrolled T-intersections considering their aggressive nature. Three intersections in the northeast region of India have been selected as the case study area. Preliminary analysis of the data revealed that drivers behave aggressively, not because they have to wait for a long time at the stop line, but because of their lack of respect for traffic rules. Binary logit models are developed for minor road right turning vehicles which show that gap acceptance behavior is influenced by gap duration, clearing time and aggressive nature of drivers. The equations obtained were used to estimate the critical gaps for aggressive and non-aggressive drivers. Critical gaps are also calculated using an existing method called clearing behavior approach. It is also shown that the estimation of critical gap is more realistic if clearing time and aggressive behavior of drivers are considered. 展开更多
关键词 Mixed traffic ACCEPTANCE Clearing timemodel Uncontrolled intersection GAP Aggressive behavior LOGIT
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Investigation of migration of pollutant at the base of Suzhou Qizishan landfill without a liner system 被引量:12
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作者 Hai-jian XIE Yun-min CHEN +4 位作者 Liang-tong ZHAN Ren-peng CHEN Xiao-wu TANG Ru-hai CHEN Han KE 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2009年第3期439-449,共11页
We investigated migration of pollutant at the base of the Suzhou landfill after it had been operated for 13 years. The investigation was carried out by performing chemical analyses on the soil samples taken from the s... We investigated migration of pollutant at the base of the Suzhou landfill after it had been operated for 13 years. The investigation was carried out by performing chemical analyses on the soil samples taken from the silty clay deposit. Concentrations of chloride, chemical oxygen demand (COD) and the heavy metals in the soil samples were determined using the standard methods. The experimental data showed that the maximum migration depth of chloride was more than 10 m, while the maximum migration depth of COD varied between 1 and 3.5 m. It is believed that the difference is attributed to the variation in diffusion rate and leachate-soil interaction. The chloride profiles also indicated that adveetion may be the dominant contaminant transport mechanism at this site. The total contents ofCu, Pb and Cr are very close to the background levels and the concentration values of these metals mainly are lower than the threshold values specified by the Chinese soil quality standard and the European one. The water-extractable concentrations of COD in the surface of the silty clay generally exceed the limit value specified by the Chinese standard. The concentrations of copper and chromium in pore water are 1-2 orders of magnitude less than the total concentrations of these heavy metals within the soils, implying that heavy metals are mainly adsorbed by the soil particles. Finally, remediation methods were suggested for this landfill site. 展开更多
关键词 Uncontrolled landfill Field investigation Contaminant migration Soil contamination Heavy metals Organic contaminants CHLORIDE
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