21,100 research outputs found
The effects of increased workload on driving performance and visual behaviour
No full textThe workload of drivers has been increasing in modern times due to the growing use of In-Vehicle systems. The higher task demand resulting from these extra visual and auditorystimuli presents an increasingly challenging problem for drivers, and has become a growing safety concern, as the higher workloads can adversely affect driving performance and must be balanced against the benefits from in-vehicle systems. Existing models suggest that when the induced workload is relatively low, drivers can deal with this increased demand by using different coping strategies; however, when the workload increases above a certain level, drivers’ performance decreases. These models are relatively simplistic and do not describe the extent to which drivers’ coping strategies can impact on the relationship between workload and performance, which are difficult to observe by traditional measures. The literature suggests that visual behaviour or eye movements, with its physiological nature, combines attributes of both attention state and human behaviour, and can be used to provide sensitive, diagnostic, and instantaneous measurements to investigate the impact of increased workload on performance, and explore associated coping strategies. An on-road experiment was therefore conducted to observe drivers’ behaviour when their workload was increased by in-vehicle secondary tasks, and the impact this had on their performance, using eye movement as well as traditional vehicle control and manoeuvring measurements. The field experiment was run under two driving scenarios of Car-Following and Free-Driving, on two road sections in Hampshire over a period of three months, using the Transportation Research Group’s Instrumented Vehicle (IV) and a FaceLabTM eye monitoring system. An Operation Simulation System was developed for drivers to perform a series of in-vehicle auditory and visual tasks through touch screen and audio systems, which reflected two different types of workload (i.e. mental and visual), with three levels of difficulty. Surveys were also conducted during and after each test run to assess drivers’ workload perception and gain an understanding of their experiences of performing the tasks, and a database established to organise all the information collected to enable subsequent analyses to be conducted readily. The results show that drivers’ behaviour was significantly impacted by additional tasks, and their secondary task performance decreased steadily with task complexity. The effects were consistent across the two Scenarios, although driving performance generally deteriorated more for the visual tasks than auditory ones, which reflects the higher conflict of visual and manual resource caused by these tasks, and all drivers took action to compensate either by increasing their headways in Car-Following, or reducing their speed in Free-Driving. The effects were reflected in their visual behaviour, which showed higher blink rates and shrunk visual searching range for the auditory tasks, i.e. a higher mental workload over baseline driving, and higher saccade and more visual transactions between different objects for the visual ones. Differences were also found in the driving and visual behaviour of individual driver characteristics groups, including gender and different experience groups. While traditional performance measurements showed many differences in behaviour due to the extra in-vehicle tasks, the different coping strategies adopted by drivers were typically observed only through the analysis of their visual behaviour. The use of these additional measurements provides an improvement to existing models for describing the relationship between workload and performance in dual-tasking
Run-up tests on a permeable slope
No full textThis report is the result of the Master of Science thesis of the author, at the Delft University of Technology, sub-Faculty of Civil Engineering. Although a lot is known nowadays about the run-up on smooth and impermeable slopes as well as the run-up on slopes covered with a rock armour layer, the physical properties of the armour layer of a rubble mound breakwater are not incorporated in the relations describing the run-up on a breakwater's slope. The roughness of a slope and its permeability, which can be described by a characteristic diameter of the armour unit and the porosity of the layer, are not used in the description of the run-up. This report is an attempt to get insight into the influence that the roughness and the permeability of a slope have on the run-up on this slope. In order to achieve this goal, dimensional parameters are derived describing the roughness of a slope and its permeability. Firstly, the framework of the design of a breakwater is given in order to place the run-up on a rough, permeable slope. The run-up itself is dealt with separately. Experiments were performed in order to obtain data that can be used to quantify the influence of the roughness of the slope and its permeability. The experiments were performed leaving the permeability of the whole structure out of consideration. To achieve a difference in porosity of the armour layer, rock armour units were used as well as tetrapod armour units. Two approaches of data analysis are applied on the data obtained from these experiments. This first approach describes the run-up on a rough, permeable slope by a combination of a roughness parameter, a permeability parameter and the breaker parameter. The roughness parameter and the permeability parameter are derived by forming non-dimensional parameters that describe roughness and permeability. The run-up, usually made non-dimensional using the wave height (H) is made non-dimensional here using the nominal diameter. This gave better results in combination with the derived parameters describing the roughness and the permeability of a slope. The second approach describes the run-up on a rough, permeable slope by using the relative run-up R.lH and a newly derived non-dimensional parameter resembling the Iribarren parameter, but incorporating the influence of the permeability of the armour layer. When the relative run-up is put against the Iribarren parameter and is put against the newly derived non-dimensional parameter, the appearing scatter is less in the latter case. In both approaches, two relations describing the run-up on a rough permeable slope are derived. One for breaking waves and one for non-breaking waves. For the second approach, the found relations have a significant resemblance with the known formulae for run-up on a slope covered with rock armour units, derived by van der Meer and Starn. When the relations derived following the both approaches are compared, the relations derived by the second approach are the relations that give the best feeling with the physical processes as they occur. The relation for non-breaking waves, derived using the first approach, is applied on data obtained from physical model tests on a breakwater covered with tetrapod armour units. The calculated nondimensional run-up is compared with the measured non-dimensional run-up. The results show that the permeability of the whole structure can not be neglected, especially inthe case of non-breaking waves.Hydraulic EngineeringCivil Engineering and Geoscience
Real Exchange Rate in China : A Long-run Perspective
No full textThis paper investigates the RMB exchange rate from a long-run viewpoint. Whether Chinas rapid economic growth brought about real exchange rate appreciation between 1975 and 2002 is empirically examined, based on a supply-side model, the BalassaSemuelson Hypothesis (BSH). The same test is conducted on Japan, Hong Kong, Korea, Malaysia, Singapore, Thailand, the Philippines, Indonesia and India. Our result indicates that the BSH only exists where the industrial structure has been upgraded and the economy has been successfully transformed from an agricultural economy to a manufacturing economy. Interestingly, China, among those where the BSH does not present, appears to be upgrading its industrial and trade structure. We then try to answer the question of why past rapid growth has no significant relationship with the RMB real exchange rate and what factors are underlying the trend of the RMB real exchange rate. We expect an appreciating trend of RMB real exchange rate in the foreseeable future, presuming that Chinas industrial upgrading process continues and the factors pertaining to the BSHs prediction, such as rise of wage rates in both tradables and nontradables, become more significant.RMB real exchange rate, economic growth
Run Kids: Exercise Physiology and Parents Practice Guide
No full textThis book focuses on the parents and how to guide and motivate their children’s physical activity,” said Yan. “The number one question I will get from parents in China is ‘If my child spends time on physical activity, won’t it take away from their academics?’ But the evidence shows physical activity enhances academic performance and improves memory and cognitive functions.” -- From the author https://www.merrimack.edu/news/merrimack-professors-book-looks-to-change-the-culture-of-youth-physical-activity-in-china
Controllable Synthesis, Diffusion Study and Catalysis of Hierarchical Zeolites
No full textHierarchical zeolites refer to zeolitic materials having bi-/multi-modal interconnective pores arranged in order of certain ranks, which improve the molecular diffusion within their frameworks, and hence the performance in their applications such as adsorption and heterogeneous catalysis. Hierarchical zeolites are commonly produced via the top-down post-synthetic treatments(such as dealumination and/or desilication) of pre-synthesized zeolites(i.e. the parent zeolites) and the bottom-up synthesis-by-design methods(such as soft/hard templating). This review presents the recent advances(mainly post 2000) in the strategies of making hierarchical zeolites, with the emphasis on the top-down approaches due to their relatively high practicality. Since hierarchical zeolites are proposed to improve intracrystalline diffusion, experimental studies of guest molecules diffusion in hierarchical zeolites are also reviewed. Additionally, catalytic applications of hierarchical zeolites, in comparison with the conventional microporous pristine zeolites, are also commented to highlight the advantages of hierarchical zeolites to improve catalysis
COMPASS polarized Drell-Yan experiment
No full textThe COMPASS II started at 2012 that includes polarized Drell-Yan program with a polarized solid target. The availability of pion beam provides an access to the Drell-Yan physics throughout the process where quark(target)-antiquark(beam) pair annihilates electromagnetically with a production of dilepton pair. Study of angular dependencies of the Drell-Yan process cross-section allows us to access to parton distribution functions (PDFs) or, more precisely, a convolutions of various PDFs. The transversely polarized target together with negative pion beam is an important feature of the COMPASS Drell-Yan experiment, that provides us with unique data on transverse momentum dependent (TMD) PDFs. After a plot run in 2014, the experiment has just started in 2015. The role of the Drell-Yan experiment at COMPASS in TMD PDFs study, with a comparison to semi-inclusive deep inelastic scattering experiment, is described. The experimental set-up, the status of the data taking in 2015 and preliminary analysis results in the 2014 run are presented. XVIth
The short-run macroeconomic impact of foreign aid to small states: An agnostic time series analysis
No full text"We herein investigate the short-run macroeconomic impact of aid in small developing countries (SDCs) by using a vector auto regression (VAR) model to study the impact of aid on net import (absorption) and domestic demand (spending). We focus on average country effects within two country sub-groups, and find substantial differences between ‘aid-dependent' SDCs and other SDCs that are more dependent on natural resources, tourism or financial services. In aid-dependent SDCs, aid absorption more or less equals spending, although only half of the aid flow is absorbed and spent. In the non-aid-dependent group, aid does not seem to be absorbed or spent in any systematic fashion." from authors' abstractForeign aid, Small states, Vector auto regression, Mean group estimator, Macroeconomic impacts, Development strategies, Public investment,
Mapping a class of run-time dependencies onto regular arrays
No full textThe production of regular computations using algorithmic engineering techniques is beginning to play an important role in the synthesis of massively parallel and VLSI processor arrays. The author widens the class of algorithms that can be formally synthesized by introducing a mapping theorem for a class of algorithms with run-time dependencies. The technique is illustrated by deriving uniform recurrences for the so-called knapsack problem, the resulting systolic array is known to be optimal
Yan Linn Aung – Grammatical recordings
No full textNine recordings in which Mr Yan Linn Aung provides some examples that demonstrate Cholim grammatical features.
This consists of the following nine sound files:
nst-cho_20150104_01_SM_H5_YanLinnAung_Grammar
nst-cho_20150104_02_SM_H5_YanLinnAung_Grammar
nst-cho_20150104_03_SM_H5_YanLinnAung_Grammar
nst-cho_20150104_04_SM_H5_YanLinnAung_Grammar
nst-cho_20150104_05_SM_H5_YanLinnAung_Grammar
nst-cho_20150104_06_SM_H5_YanLinnAung_Grammar
nst-cho_20150104_07_SM_H5_YanLinnAung_Grammar
nst-cho_20150104_08_SM_H5_YanLinnAung_Grammar
nst-cho_20150119_01_SM_H5_YanLinnAung_Grammar
nst-cho_20150119_02_SM_H5_YanLinnAung_Grammar
The detials of these recordings are as follows:
nst-cho_20150104_01_SM_H5_YanLinnAung_Grammar_Duration 3’36”, Word List, word for ‘fat’ do³, pi²pjo³ ‘flower’
nst-cho_20150104_02_SM_H5_YanLinnAung_Grammar_Duration 1’09”, Word List, ne² ‘paddy field’ and ne³ ‘ear’
nst-cho_20150104_03_SM_H5_YanLinnAung_Grammar_Duration 6’45”, Word List pʰai² ‘left side’, tsai¹ ‘right side’ , ‘year’ &c
nst-cho_20150104_04_SM_H5_YanLinnAung_Grammar_Duration 0’46”, Word List, verbs tsa² ‘be born’ ɪtsa³ ‘be born, nominalised form’
nst-cho_20150104_05_SM_H5_YanLinnAung_Grammar_Duration 20’28”, Word List, verbs in nominalised and verbal forms: tsa² ‘be born’ ɪtsa³ ‘be born, nominalised form’ and others, CALMSEA list up to ‘white’
nst-cho_20150104_06_SM_H5_YanLinnAung_Grammar_Duration 2’12”, Word List, verbs in nominalised and verbals forms, CALMSEA list from ‘eat’ up to ‘give’
nst-cho_20150104_07_SM_H5_YanLinnAung_Grammar_Duration 10’56”, Word List, verbs in nominalised and verbals forms, CALMSEA list from ‘lick’ to ‘roll’
nst-cho_20150104_08_SM_H5_YanLinnAung_Grammar_Duration 1’31”, Tone marks of the agreement markers
nst-cho_20150119_01_SM_H5_YanLinnAung_Grammar_Duration 0’50”, Tonal variation between differences; I did not run /ʒɯ¹ maŋ²/ and the causative /ʒɯ³ maŋ²/ ‚I did not make (him) flee‘. Also past tense.
nst-cho_20150119_02_SM_H5_YanLinnAung_Grammar_Duration 0’16”, The word for ‘self’ /kʰu³ʃi¹
Determination of the efficiency of the hodoscopes during the Drell-Yan run
No full textThe COMPASS trigger system is mainly composed of fast plastic scintillators working as hodoscopes. For the selection of events of physical interest during the COMPASS Drell-Yan run in 2015 it was configured to trigger single- and dimuon-events. Unbiased trigger decisions can be used to determine the efficiency of the six symmetrically oriented hodoscopes used in 2015. The unbiasedness of the trigger is based on the usage of the hadron calorimeter trigger (CT) which was used on two dates during the run: The first time in the beginning and the second one in the middle respectively. Due to different beam conditions between the two dates a direct comparison between the results is unfortunately difficult. Especially in the beginning of the run, most of the strips of different hodoscopes show between 90% and often even 100%-efficiency. Compared to the results from the middle of the run, the efficiency of several strips seemed to get much worse during this time. Furthermore it can be seen that the method of determining the efficiency for each hodoscope strip separately works only for those hodoscopes where the track resolution is several times smaller than the strip width. Unfortunately a confirmation of this trend for dates earlier and later cannot be created by using the same methods since no further data sets with CT trigger exist
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