A
bstract
This report details the capabilities of LHCb and its upgrades towards the study of kaons and hyperons. The analyses performed so far are reviewed, elaborating on the prospects for some key ...decay channels, while proposing some new measurements in LHCb to expand its strangeness research program.
Microelectromechanical Systems (MEMS) technology is playing a key role in the design of the new generation of smartphones. Thanks to their reduced size, reduced power consumption, MEMS sensors can be ...embedded in above mobile devices for increasing their functionalities. However, MEMS cannot allow accurate autonomous location without external updates, e.g., from GPS signals, since their signals are degraded by various errors. When these sensors are fixed on the user's foot, the stance phases of the foot can easily be determined and periodic Zero velocity UPdaTes (ZUPTs) are performed to bound the position error. When the sensor is in the hand, the situation becomes much more complex. First of all, the hand motion can be decoupled from the general motion of the user. Second, the characteristics of the inertial signals can differ depending on the carrying modes. Therefore, algorithms for characterizing the gait cycle of a pedestrian using a handheld device have been developed. A classifier able to detect motion modes typical for mobile phone users has been designed and implemented. According to the detected motion mode, adaptive step detection algorithms are applied. Success of the step detection process is found to be higher than 97% in all motion modes.
In this paper a novel step length model using a handheld Micro Electrical Mechanical System (MEMS) is presented. It combines the user's step frequency and height with a set of three parameters for ...estimating step length. The model has been developed and trained using 12 different subjects: six men and six women. For reliable estimation of the step frequency with a handheld device, the frequency content of the handheld sensor's signal is extracted by applying the Short Time Fourier Transform (STFT) independently from the step detection process. The relationship between step and hand frequencies is analyzed for different hand's motions and sensor carrying modes. For this purpose, the frequency content of synchronized signals collected with two sensors placed in the hand and on the foot of a pedestrian has been extracted. Performance of the proposed step length model is assessed with several field tests involving 10 test subjects different from the above 12. The percentages of error over the travelled distance using universal parameters and a set of parameters calibrated for each subject are compared. The fitted solutions show an error between 2.5 and 5% of the travelled distance, which is comparable with that achieved by models proposed in the literature for body fixed sensors only.
Most portable systems like smart-phones are equipped with low cost consumer grade sensors, making them useful as Pedestrian Navigation Systems (PNS). Measurements of these sensors are severely ...contaminated by errors caused due to instrumentation and environmental issues rendering the unaided navigation solution with these sensors of limited use. The overall navigation error budget associated with pedestrian navigation can be categorized into position/displacement errors and attitude/orientation errors. Most of the research is conducted for tackling and reducing the displacement errors, which either utilize Pedestrian Dead Reckoning (PDR) or special constraints like Zero velocity UPdaTes (ZUPT) and Zero Angular Rate Updates (ZARU). This article targets the orientation/attitude errors encountered in pedestrian navigation and develops a novel sensor fusion technique to utilize the Earth's magnetic field, even perturbed, for attitude and rate gyroscope error estimation in pedestrian navigation environments where it is assumed that Global Navigation Satellite System (GNSS) navigation is denied. As the Earth's magnetic field undergoes severe degradations in pedestrian navigation environments, a novel Quasi-Static magnetic Field (QSF) based attitude and angular rate error estimation technique is developed to effectively use magnetic measurements in highly perturbed environments. The QSF scheme is then used for generating the desired measurements for the proposed Extended Kalman Filter (EKF) based attitude estimator. Results indicate that the QSF measurements are capable of effectively estimating attitude and gyroscope errors, reducing the overall navigation error budget by over 80% in urban canyon environment.
The EasyMED process is composed of an association of simple ‘‘human-size’’ elementary cells. The plates, frames and grids constituting each cell are easy to construct and transport
1. The cells can ...be combined in parallel and series to form evaporators with variable capacity. In order to demonstrate the performances of this new process, a laboratory unit was constructed. It is composed of five evaporation-condensation cells. Three operate in series and two in parallel. The distillation of synthetic salted water is studied and brine is recycled to avoid consumption and waste of large quantities of salt. The heat carrier fluid is hot water produced by electric devices. The influence of operating parameters like heating fluid flowrates, temperature difference between effects is investigated. The optimal film flowrate deduced from previous tests is 200 L/h/cell
1. The average distilled water production is 0.95 m
3/d. The distillate conductivity is less than 12
μS/cm. The measured thermal performances are satisfactory: thermal efficiency ≈77%, gain output ratio ≈2.6. The overall heat transfer coefficients between condensation cell and evaporation cell of the next effect reached 2500 W.m
−2.K
−1 for a temperature difference of 3–4°C. The coefficient between heating cell and evaporation cell of the first effect is around 1100 W.m
−2.K
−1. These performances are promising, and by increasing the number of effects in series in a larger industrial unit, the GOR will be largely increased and the specific consumption decreased.
A new multi-effect plate evaporator, EasyMED, is presented. This patented process 1 is applicable for seawater desalination using simple and modular technology. Experimental results from the ...hydrodynamics and thermal performances obtained with a one-effect laboratory unit with 0.4 m
3/d distilled water production were analysed. The hydrodynamics study shows the importance of the grids used to improve salted water film stability and to promote turbulence. A film distribution system was designed to ensure good plate wetting for flow rates lower than 50 L/h. Baffles were added in the heating and cooling cells to increase the heat transfer coefficient. The influence of heat carrier fluid and salted water film flow rates on performance was studied. The production of distilled water ranged between 0.3 and 0.4 m
3/d for one plate whose area is 0.72 m
2. Distillate conductivity was very low. The evaporation ratio ranged between 10% and 50%. The mean heat exchange coefficient between heating cell and evaporating film was around 1100 W.m
−2.K
−1. These results were higher than those obtained with a first pilot in 2000 2. The results were modelled in order to distinguish the three thermal resistances implied in the transfer. It is shown that the film flow may be considered as turbulent even at low Reynolds numbers due to the influence of the grids.
A new model has been developed to predict the clogging behaviour of high-efficiency particulate air filters. The model takes into account the heterogeneous deposit of particles inside the filter ...medium. The filter is considered to be a series of elementary slices which are assumed to be homogeneously loaded by aerosol. Particles are assumed to form dendrites which can be considered as newly formed fibres. For each time increment and for each slice, particle collection efficiency of initial and new fibres is calculated according to the Payet model in order to give an overall prediction of the mass of aerosol deposited and the pressure drop. Model results are compared with experimental results.
Exergy analysis has been shown to be an efficient tool for understanding and improvement of industrial processes. In the present study, exergy analysis has been used to examine the energy consumption ...of an existing Steam Methane Reforming (SMR) process and then to test for possible savings in primary energy consumption and environmental protection.
In the first step, energy and exergy balances of a steam methane reforming process were established to identify the thermodynamic imperfections of the process. Recommendations from this study have contributed to the building of a new and more efficient process. Consequently, a heat exchanger, corresponding to 44.9% of the total required area for the SMR heat exchange, has been incorporated in the SMR for waste heat recovery.
The thermal and exergetic efficiencies of the original process are 70% and 65.5%, respectively. For the new process, the thermal and exergetic efficiencies are 74% and 69.1%, respectively. The unused exergy is reduced by 9.3% from 125.9 to 114.2kJ per mole of H2 produced. One mole of methane produces 2.48mol of H2 compared to 2.35mol of H2 produced in the original process. Furthermore, the new SMR process produces the lower greenhouse gas emissions.
► Exergy analysis is used for evaluating a steam methane reforming process and for guiding efficiency-improvement efforts. ► The main part of the processes exergy destroyed occurs in the chemical reactors. ► To improve the exergetic efficiency the system components should be improved and/or the exhaust exergy should be decreased. ► Heat recovery not only helps to save energy but also decreases the environmental impact.
EasyMED, a new MED process constructed with plates has shown good performances for desalination of salted water in laboratory with only one effect
1. In order to prove the reliability of this process ...in real conditions, a three effects evaporator was recently built in La Spezia Italy (see Fig. 1). This unit is composed of three effects in series and five cells in parallel and is heated by hot water at about 75°C. 3 m
3/d of high quality distillate with a conductivity lower than 20
μS/cm was obtained. The evaporation ratio ranged between 8 and 13%. To avoid large consumption of energy to preheat seawater up to its boiling point, about 80% of the brine is recycled to the evaporator inlet. The overall heat transfer coefficients between heating water and seawater falling film reached 1400 W·m
−2·K
−1 whereas the coefficient between condensing vapour and evaporating seawater is about 4000 W·m
−2·K
−1. Temperature difference between the heating cells and the first evaporation cells is around 11°C. For the rest of the unit, the temperature difference between condensation cells and evaporation cells of the next effect is between 3 and 6°C. The first results concerning the influence of the heating fluid temperature and the heating fluid flowrate are presented.
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