The Impact of Intersection Geometry and Control Type on Fuel Consumption Cost at Various Types at the Level of Service

2016 ◽  
Vol 7 (3) ◽  
pp. 1-16
Author(s):  
A Abdalla ◽  
M Basiouny ◽  
Ahmed Khater
Keyword(s):  
Fuel Consumption ◽  
Level Of Service ◽  
Consumption Cost ◽  
Intersection Geometry ◽  
And Control ◽  
The Impact

Multidisciplinary Assessment of the Control of the Propellers of a Pusher Geared Open Rotor—Part I: Zero-Dimensional Performance Model for Counter-Rotating Propellers

2016 ◽  
Vol 138 (7) ◽  
Author(s):  
Pablo Bellocq ◽  
Inaki Garmendia ◽  
Vishal Sethi ◽  
Alexis Patin ◽  
Stefano Capodanno ◽  
...  
Keyword(s):  
Wind Tunnel ◽  
Fuel Consumption ◽  
Test Data ◽  
Wind Tunnel Test ◽  
Performance Model ◽  
Preliminary Design ◽  
Open Rotor ◽  
And Control ◽  
The Impact ◽  
A Performance

Due to their high propulsive efficiency, counter-rotating open rotors (CRORs) have the potential to significantly reduce fuel consumption and emissions relative to conventional high bypass ratio turbofans. However, this novel engine architecture presents many design and operational challenges both at engine and aircraft level. The assessment of the impact of the main low-pressure preliminary design and control parameters of CRORs on mission fuel burn, certification noise, and emissions is necessary at preliminary design stages in order to identify optimum design regions. These assessments may also aid the development process when compromises need to be performed as a consequence of design, operational, or regulatory constraints. The required preliminary design simulation tools should ideally be 0D or 1D (for computational purposes) and should capture the impact of the independent variation of the main low-pressure system design and control variables, such as the number of blades, diameter and rotational speed of each propeller, the spacing between the propellers, and the torque ratio (TR) of the gearbox or the counter-rotating turbine (CRT), among others. From a performance point of view, counter-rotating propellers (CRPs) have historically been modeled as single propellers. Such a performance model does not provide the required flexibility for a detailed design and control study. Part I of this two-part publication presents a novel 0D performance model for CRPs allowing an independent definition of the design and operation of each of the propellers. It is based on the classical low-speed performance model for individual propellers, the interactions between them, and a compressibility correction which is applied to both propellers. The proposed model was verified with publicly available wind tunnel test data from NASA and was judged to be suitable for preliminary design studies of geared and direct drive open rotors. The model has to be further verified with high-speed wind tunnel test data of highly loaded propellers, which was not found in the public domain. In Part II, the novel CRP model is used to produce a performance model of a geared open rotor (GOR) engine with a 10% clipped propeller designed for a 160 PAX and 5700 NM aircraft. This engine model is first used to study the impact of the control of the propellers on the engine specific fuel consumption (SFC). Subsequently, it was integrated in a multidisciplinary simulation platform to study the impact of the control of the propellers on engine weight, certification noise, and NOx emission.

Advanced 0-D Performance Modelling of Counter Rotating Propellers for Multi-Disciplinary Preliminary Design Assessments of Open Rotors

2014 ◽  
Author(s):  
Pablo Bellocq ◽  
Vishal Sethi ◽  
Stefano Capodanno ◽  
Alexis Patin ◽  
Fernando Rodriguez Lucas
Keyword(s):  
Fuel Consumption ◽  
Low Pressure ◽  
Performance Model ◽  
Preliminary Design ◽  
Performance Modelling ◽  
Performance Point ◽  
Regulatory Constraints ◽  
And Control ◽  
The Impact ◽  
A Performance

Due to their high propulsive efficiency, Counter Rotating Open Rotors (CRORs) have the potential to significantly reduce fuel consumption and emissions relative to conventional high bypass ratio turbofans. However, this novel engine architecture presents many design and operational challenges both at engine and aircraft level. The assessment of the impact of the main low pressure preliminary design and control parameters of CRORs on mission fuel burn, certification noise and emissions is necessary at preliminary design stages in order to identify optimum design regions. These assessments may also aid the development process when compromises need to be performed as a consequence of design, operational or regulatory constraints. The required preliminary design simulation tools should ideally be 0-D or 1-D (for computational purposes) and should capture the impact of the independent variation of the main low pressure system design and control variables such as: the number of blades, diameter and rotational speed of each propeller, the spacing between the propellers and the torque ratio of the gearbox or the counter rotating turbine amongst others. From a performance point of view, counter rotating propellers have historically been modelled as single propellers. Such a performance model does not provide the required flexibility for a detailed design and control study. This paper presents a novel 0-D performance model for Counter Rotating Propellers (CRPs) based on the classical low speed performance model for individual propellers and the interactions between them. This model also incorporates a compressibility correction which is applied to both propellers. The proposed model is verified with publicly available wind tunnel test data from NASA. The novel 0-D counter rotating propeller performance model is used to produce a performance model of a geared Open Rotor engine with a 10% clipped propeller. This engine model is first used to study the impact of the control of the propellers on the cruise fuel consumption. Subsequently, the engine performance model is integrated in a multi-disciplinary simulation platform to study the impact of the control of the propellers on the certification noise. The results of this case study show that 1–2% SFC savings at cruise are possible and an optimal control schedule is identified. It is also concluded that significant certification noise reductions are possible through an adequate control of the rotational speeds of the propellers.

HEAC and THYCS Projects

2006 ◽  
Author(s):  
Stefano Mola ◽  
Stefania Martini ◽  
Maria Laura Parodi ◽  
Giulio Lo Presti ◽  
Carloandrea Malvicino
Keyword(s):  
Thermal Comfort ◽  
Fuel Consumption ◽  
Air Conditioning ◽  
Environmental Concern ◽  
Research Activity ◽  
Air Conditioning System ◽  
Rapid Action ◽  
Hot Weather ◽  
And Control ◽  
The Impact

Due to its more and more widespread diffusion, Air Conditioning (A/C) systems in automobiles will face two main challenges in the near future: to improve the evaluation and control of perceived thermal comfort, and to reduce the fuel consumption increase due to its use (up to 70% in urban operation under hot weather [1]). In view of future regulations and heightening environmental concern, rapid action is needed to reduce such negative A/C impact. Moreover, the A/C system has also an important role in safety, since it has to assure the driver’s visibility by avoiding fogging formation on the windshield in any condition of use. This function has to be assured in the most reliable and automatic way, minimising the interaction of the driver with the A/C system itself. The two research projects described in the present paper have the following goals: • To improve the perceived thermal comfort evaluation. • To lower the impact of air conditioning system on fuel consumption. • To detect incipient fogging conditions in a reliable and predictive way. The research activity has been performed with the following constraints: • To minimize the number of sensors. • To reduce the cost of the air conditioning system.

scholarly journals THE IMPACT OF FREIGHT VEHICLE ACCESS RESTRICTION ON THE SUSTAINABILITY OF JAKARTA INTRA URBAN TOLLWAY SYSTEM

2018 ◽  
Vol 16 (5) ◽  
Author(s):  
Nahry Yusuf
Keyword(s):  
Fuel Consumption ◽  
Positive Impact ◽  
Sustainable Transportation ◽  
Fatality Rate ◽  
Sustainable Transport ◽  
Restriction Policy ◽  
Before And After ◽  
Consumption Cost ◽  
Accident Victim ◽  
The Impact

Freight vehicle access restriction policy in 2011 has had an impact on the performance of Jakarta Intra Urban Tollway (JIUT) system. The purpose of this study is to analyse the impact of the policy on Jakarta Intra Urban Toll way system before and after its implementation and to analyse the impact that occurs without the implementation of this policy by using the sustainable transportation indicators as the research parameters. The assessment results of the parameters (speed, amount of fuel consumption, cost of fuel consumption, fatality rate, cost of accident victim, amount of CO2 emissions, cost of carbon pollution, and noise level) indicate that freight vehicle access restriction policy has a positive impact on traffic smoothness and safety but does not support overall urban sustainable transportation in JIUT system. In addition, if the policy was not implemented, its impact would have been worse than the current condition. It implies that the implementation of the policy is a right decision though some parameters should be improved to attain sustainable transport system.

scholarly journals THE IMPACT OF FREIGHT VEHICLE ACCESS RESTRICTION ON THE SUSTAINABILITY OF JAKARTA INTRA URBAN TOLLWAY SYSTEM

2018 ◽  
Vol 16 ◽  
Author(s):  
Nahry Yusuf
Keyword(s):  
Fuel Consumption ◽  
Positive Impact ◽  
Sustainable Transportation ◽  
Fatality Rate ◽  
Sustainable Transport ◽  
Restriction Policy ◽  
Before And After ◽  
Consumption Cost ◽  
Accident Victim ◽  
The Impact

Freight vehicle access restriction policy in 2011 has had an impact on the performance of Jakarta Intra Urban Tollway (JIUT) system. The purpose of this study is to analyse the impact of the policy on Jakarta Intra Urban Toll way system before and after its implementation and to analyse the impact that occurs without the implementation of this policy by using the sustainable transportation indicators as the research parameters. The assessment results of the parameters (speed, amount of fuel consumption, cost of fuel consumption, fatality rate, cost of accident victim, amount of CO2 emissions, cost of carbon pollution, and noise level) indicate that freight vehicle access restriction policy has a positive impact on traffic smoothness and safety but does not support overall urban sustainable transportation in JIUT system. In addition, if the policy was not implemented, its impact would have been worse than the current condition. It implies that the implementation of the policy is a right decision though some parameters should be improved to attain sustainable transport system.

Suppressed, but Not Forgotten

2011 ◽  
Vol 70 (1) ◽  
pp. 5-11 ◽  
Author(s):  
Beat Meier ◽  
Anja König ◽  
Samuel Parak ◽  
Katharina Henke
Keyword(s):  
Memory Trace ◽  
Thought Suppression ◽  
Test Phase ◽  
Indirect Test ◽  
Final Test ◽  
Test Experiment ◽  
And Control ◽  
Cue Words ◽  
The Impact

This study investigates the impact of thought suppression over a 1-week interval. In two experiments with 80 university students each, we used the think/no-think paradigm in which participants initially learn a list of word pairs (cue-target associations). Then they were presented with some of the cue words again and should either respond with the target word or avoid thinking about it. In the final test phase, their memory for the initially learned cue-target pairs was tested. In Experiment 1, type of memory test was manipulated (i.e., direct vs. indirect). In Experiment 2, type of no-think instructions was manipulated (i.e., suppress vs. substitute). Overall, our results showed poorer memory for no-think and control items compared to think items across all experiments and conditions. Critically, however, more no-think than control items were remembered after the 1-week interval in the direct, but not in the indirect test (Experiment 1) and with thought suppression, but not thought substitution instructions (Experiment 2). We suggest that during thought suppression a brief reactivation of the learned association may lead to reconsolidation of the memory trace and hence to better retrieval of suppressed than control items in the long term.

Research Participation Experiences of Informants of Suicide and Control Cases

Crisis ◽  
2010 ◽  
Vol 31 (5) ◽  
pp. 238-246 ◽  
Author(s):  
Paul W. C. Wong ◽  
Wincy S. C. Chan ◽  
Philip S. L. Beh ◽  
Fiona W. S. Yau ◽  
Paul S. F. Yip ◽  
...  
Keyword(s):  
Ethical Issues ◽  
Research Participation ◽  
Self Report ◽  
Initial Contact ◽  
Psychological Autopsy ◽  
Autopsy Study ◽  
The People ◽  
And Control ◽  
The Impact

Background: Ethical issues have been raised about using the psychological autopsy approach in the study of suicide. The impact on informants of control cases who participated in case-control psychological autopsy studies has not been investigated. Aims: (1) To investigate whether informants of suicide cases recruited by two approaches (coroners’ court and public mortuaries) respond differently to the initial contact by the research team. (2) To explore the reactions, reasons for participation, and comments of both the informants of suicide and control cases to psychological autopsy interviews. (3) To investigate the impact of the interviews on informants of suicide cases about a month after the interviews. Methods: A self-report questionnaire was used for the informants of both suicide and control cases. Telephone follow-up interviews were conducted with the informants of suicide cases. Results: The majority of the informants of suicide cases, regardless of the initial route of contact, as well as the control cases were positive about being approached to take part in the study. A minority of informants of suicide and control cases found the experience of talking about their family member to be more upsetting than expected. The telephone follow-up interviews showed that none of the informants of suicide cases reported being distressed by the psychological autopsy interviews. Limitations: The acceptance rate for our original psychological autopsy study was modest. Conclusions: The findings of this study are useful for future participants and researchers in measuring the potential benefits and risks of participating in similar sensitive research. Psychological autopsy interviews may be utilized as an active engagement approach to reach out to the people bereaved by suicide, especially in places where the postvention work is underdeveloped.

Using Work Domain Analysis to Evaluate the Impact of Digitization on Command and Control

2008 ◽  
Author(s):  
Daniel P. Jenkins ◽  
Neville A. Stanton ◽  
Paul M. Salmon ◽  
Guy H. Walker
Keyword(s):  
Command And Control ◽  
Domain Analysis ◽  
Work Domain Analysis ◽  
And Control ◽  
The Impact ◽  
Work Domain

Experimental Study of the Impact of Alisma plantago-aquatica Secretions on Pathogenic Bacteria

2014 ◽  
Vol 1 (3) ◽  
pp. 3-7
Author(s):  
O. Zhukorskyy ◽  
O. Hulay
Keyword(s):  
Pathogenic Bacteria ◽  
Initial Density ◽  
Biologically Active ◽  
Erysipelothrix Rhusiopathiae ◽  
Natural Focus ◽  
Test Species ◽  
Popula Tions ◽  
And Control ◽  
The Impact

Aim. To estimate the impact of in vivo secretions of water plantain (Alisma plantago-aquatica) on the popula- tions of pathogenic bacteria Erysipelothrix rhusiopathiae. Methods. The plants were isolated from their natural conditions, the roots were washed from the substrate residues and cultivated in laboratory conditions for 10 days to heal the damage. Then the water was changed; seven days later the selected samples were sterilized using fi lters with 0.2 μm pore diameter. The dilution of water plantain root diffusates in the experimental samples was 1:10–1:10,000. The initial density of E. rhusiopathiae bacteria populations was the same for both experimental and control samples. The estimation of the results was conducted 48 hours later. Results. When the dilution of root diffusates was 1:10, the density of erysipelothrixes in the experimental samples was 11.26 times higher than that of the control, on average, the dilution of 1:100 − 6.16 times higher, 1:1000 – 3.22 times higher, 1:10,000 – 1.81 times higher, respectively. Conclusions. The plants of A. plantago-aquatica species are capable of affecting the populations of E. rhusiopathiae pathogenic bacteria via the secretion of biologically active substances into the environment. The consequences of this interaction are positive for the abovementioned bacteria, which is demon- strated by the increase in the density of their populations in the experiment compared to the control. The intensity of the stimulating effect on the populations of E. rhusiopathiae in the root diffusates of A. plantago-aquatica is re- ciprocally dependent on the degree of their dilution. The investigated impact of water plantain on erysipelothrixes should be related to the topical type of biocenotic connections, the formation of which between the test species in the ecosystems might promote maintaining the potential of natural focus of rabies. Keywords: Alisma plantago-aquatica, in vivo secretions, Erysipelothrix rhusiopathiae, population density, topical type of connections.

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