Soil conditioning for EPBMs

Nowadays, the Earth Pressure Balanced (EPB) shields are used more and more caused by both the mechanical development of the machines and the more effective use of additives such as foams and polymers. These additives are used to condition spoil in the screw conveyor. A crucial component of EPB tunnelling applications is ground conditioning. Thus, in order to permit quantitative measurements of the conditioned ground behavior, it is necessary to develop and use a test able to simulate the extraction of earth from the chamber with a screw conveyor. This reliable test procedure can provide quantitative parameters that can really describe the conditioned soil behavior.

Laboratory tests for EPB tunnelling soil conditioning

The screw conveyor system plays a fundamental role during the EPB tunnelling operations for the tunnel face pressure control. On the other hand, the use of additives such chemical foams is even more applied in order to extend the EPB technology to the cohesionless soils. Despite the extensive use of the EPB technique in urban environment, little knowledge exists in the understanding of the behavior of such conditioned soil during the excavation operations. At the Turin University of Technology the Tunnelling and Underground Space Centre, in the mainframe of a wider research on soil conditioning, has developed an experimental apparatus that simulates the extraction phase with screw conveyor from a pressurized tank. In this paper the apparatus is presented and the results of a first series of tests carried out on sand are discussed. © 2007 Taylor & Francis Group.

Soil conditioning of sand for EPB applications:A laboratory research

EPB tunnelling requires the application of soil conditioning to increase its field of applicability particularly for cohesionless soils. Choosing the most suitable conditioning set for the various soils requires the use of a feasible laboratory test which can permit to define the characteristics of the conditioned soils and provide measurable data. A series of tests has been carried out using a laboratory screw conveyor device which was designed for this purpose and which simulates the extraction of the spoil from a pressure chamber in a similar way as in EPB tunnelling. The tested soils were medium-grain sands with varying amounts of silt and the tested conditioned mixtures were obtained with different water contents and amounts of foam. A simple slump test was also used to analyze the global characteristics of the conditioned soils. The test has shown that the proposed laboratory procedure permits a quantitative comparison to be made between different conditioning amounts and agents on the basis of measurable parameters. © 2007 Elsevier Ltd. All rights reserved.

Soil Conditioning and Ground Monitoring for Shield Tunnelling

Soil conditioning consists of mixing and remolding the natural material during the mechanical excavation of tunnels, generally at low depth, with additives, in order to obtain suitable properties of plasticity and consistency for the excavated material, so becoming able to apply a counterpressure against natural earth pressure and groundwater flow towards the excavation chamber. The assessment and the control of the soil parameters and of machine performance are fundamental for a regular and safe excavation, also with regards to surface stability. This paper mainly focus on testing approach aimed to the proper soil conditioning with EPB shields, whose results have been validated at real scale. The influence of the water content and the amount of conditioning foam has been studied by the Authors. A proper definition of conditioning parameters can allow to extend the application field of Earth Pressure Balance (EPB) tunnel machines to various grain soil distribution, even in weak rock formations (e.g. siltstone or flysch). Importance of conditioning is reflected also on the possibility of a proper spoil disposal or better for its reuse.

Treatment of relapse after allogeneic bone marrow transplantation with reduced intensity conditioning (FLAG +/- Ida) and second allogeneic stem cell transplant

Acute leukaemias in relapse after allogeneic stem cell transplantation (SCT) respond poorly to donor leucocyte infusions (DLI) compared with chronic myeloid leukaemia (CML), at least in part because of faster disease kinetics. Fludarabine-containing 'non-myeloablative' chemotherapy followed by further allo SCT may offer more rapid and effective disease control. We report 14 patients with relapse after allo SCT for acute leukaemia [seven acute myeloid leukaemia (AML), five acute lymphoblastic leukaemia (ALL)] or refractory anaemia with excess blasts in transformation (RAEB-t, n = 2) treated with fludarabine, high-dose cytosine arabinoside (ara-C) and granulocyte colony-simulating factor (G-CSF) with (n = 10) or without (n = 2) idarubicin (FLAG +/- Ida) or DaunoXome (FLAG-X) (n = 2) and second allo SCT from the original donor. Donors were fully human leucocyte antigen (HLA) -matched in 13 cases with a single class A mismatch in one. Actuarial overall survival was 60% and disease-free survival was 26% at 58 months. Remissions after the second SCT were longer than those after the first bone marrow transplantation (BMT) in eight of the 13 assessable patients to date. Haematopoietic recovery was rapid. Transplants were well tolerated with no treatment-related deaths. The major complication was graft-versus-host disease (GvHD, acute >/= grade II-2 cases, chronic - eight cases, two limited, six extensive) although there have been no deaths attributable to this. FLAG +/- Ida and second allo SCT is a safe and useful approach and may be more effective than DLI in the treatment of acute leukaemias relapsing after conventional allo SCT.

Short Report:Engraftment of T-cell-depleted allogeneic haematopoietic stem cells using a reduced intensity conditioning regimen

Graft-versus-host disease (GVHD) remains a significant complication in patients undergoing allogeneic stem cell transplantation (SCT) using a reduced intensity conditioning regimen. Although T-cell depletion (TCD) reduces the risk of GVHD after a myeloablative conditioning regimen, it is associated with an increased risk of graft failure. We have therefore examined whether TCD compromises engraftment using a fludarabine-based conditioning regimen. Fifteen patients have been transplanted using such a regimen of whom 13 underwent ex vivo TCD. All but one patient demonstrated durable engraftment and no patient receiving a TCD product developed severe GVHD. Thus, TCD may play a role in GvHD prophylaxis using such regimens.

Behavioural and neural correlates of operant conditioning in Lymnaea stagnalis : role of previous experience during development /

The freshwater mollusc Lymnaea stagnalis was utilized in this study to further the understanding of how network properties change as a result of associative learning, and to determine whether or not this plasticity is dependent on previous experience during development. The respiratory and neural correlates of operant conditioning were first determined in normally reared Lymnaea. The same procedure was then applied to differentially reared Lymnaea, that is, animals that had never experienced aerial respiration during their development. The aim was to determine whether these animals would demonstrate the same responses to the training paradigm. In normally reared animals, a behavioural reduction in aerial respiration was accompanied by numerous changes within the neural network. Specifically, I provide evidence of changes at the level of the respiratory central pattern generator and the motor output. In the differentially reared animals, there was little behavioural data to suggest learning and memory. There were, however, significant differences in the network parameters, similar to those observed in normally reared animals. This demonstrated an effect of operant conditioning on differentially reared animals. In this thesis, I have identified additional correlates of operant conditioning in normally reared animals and provide evidence of associative learning in differentially reared animals. I conclude plasticity is not dependent on previous experience, but is rather ontogenetically programmed within the neural network.

Fit For Action: A Comparative Case Study of the Implementation of an Adaptive Fitness and Conditioning Program for Moderate Functioning Teens and Transition Age Youth with ASD

The purpose of my research was to develop and refine pedagogic approaches, and establish fitness baselines to adapt fitness and conditioning programs for Moderate-functioning ASD individuals. I conducted a seven-week study with two teens and two trainers. The trainers implemented individualized fitness and conditioning programs that I developed. I conducted pre and post fitness baselines for each teen, a pre and post study interview with the trainers, and recorded semi-structured observations during each session. I used multi-level, within-case and across case analyses, working inductively and deductively. My findings indicated that fundamental movement concepts can be used to establish fitness baselines and develop individualized fitness programs. I tracked and evaluated progressions and improvements using conventional measurements applied to unconventional movements. This process contributed to understanding and making relevant modifications to activities as effective pedagogic strategies for my trainers. Further research should investigate fitness and conditioning programs with lower functioning ASD individuals.

Natural air conditioning, traditions and trends : high performance of sustainable indoor ventilation in a hot and dry climate

De nos jours, l'utilisation accrue de combustibles à base de fossiles et l'électricité met en péril l'environnement naturel à cause des niveaux élevés de pollution. Il est donc plausible de prévoir des économies d'énergie significatives grâce à la climatisation dite «naturelle»». En accord avec les objectifs acceptés à l'échelle internationale d'une architecture «verte» et durable, l'utilisation de cours intérieures associées aux capteurs de vent, aux murs-Trombe et à d'autres systèmes de climatisation naturelle (aussi bien traditionnels que nouveaux), paraît prometteuse. Ce mémoire propose une analyse de nouvelles approches à la climatisation naturelle et à la production d'air frais avec une consommation minimale d'énergie, eu égard aux traditions et aux tendances, en particulier dans les zones climatiques chaudes et sèches comme l'Iran. Dans ce contexte, regarder l'architecture de l'Islam et la discipline du Qur'an paraissent offrir un guide pour comprendre l'approche musulmane aux processus de décision en design. Nous regardons donc les traditions et les tendances en ce qui concerne la climatisation naturelle à travers l'élément le plus important du contexte islamique, à savoir le Qur'an. C'est pourquoi, à l'intérieur du thème de la tradition, nous avons pris en compte quelques considérations concernant l'influence de l'Islam, et en particulier le respect de la nature associé à un équilibre entre l'harmonie et l'individualité. Ce sont autant de facteurs qui influencent la prise de décisions visant à résoudre des problèmes scientifiques majeurs selon la philosophie et les méthodes islamiques ; ils nous permettent de faire quelques recommandations. La description des principes sous-jacents aux capteurs à vent et des antécédents trouvés dans la nature tels que les colonies de termites, est présentée également. Sous la rubrique tendances, nous avons introduit l'utilisation de matériaux et de principes de design nouveaux. Regarder simultanément ces matériaux nouveaux et l'analogie des colonies de termites suggère de bonnes approches à la conception d'abris pour les victimes de tremblements de terre dans les régions sisimques. Bam, une ville iranienne, peut être considérée comme un exemple spécifique illustrant où les principes exposés dans ce mémoire peuvent s'appliquer le plus adéquatement.

Qualitative Air Flow Modelling and Analysis of Data Centre Air Conditioning as Multiple Jet Array

Data centre is a centralized repository,either physical or virtual,for the storage,management and dissemination of data and information organized around a particular body and nerve centre of the present IT revolution.Data centre are expected to serve uniinterruptedly round the year enabling them to perform their functions,it consumes enormous energy in the present scenario.Tremendous growth in the demand from IT Industry made it customary to develop newer technologies for the better operation of data centre.Energy conservation activities in data centre mainly concentrate on the air conditioning system since it is the major mechanical sub-system which consumes considerable share of the total power consumption of the data centre.The data centre energy matrix is best represented by power utilization efficiency(PUE),which is defined as the ratio of the total facility power to the IT equipment power.Its value will be greater than one and a large value of PUE indicates that the sub-systems draw more power from the facility and the performance of the data will be poor from the stand point of energy conservation. PUE values of 1.4 to 1.6 are acievable by proper design and management techniques.Optimizing the air conditioning systems brings enormous opportunity in bringing down the PUE value.The air conditioning system can be optimized by two approaches namely,thermal management and air flow management.thermal management systems are now introduced by some companies but they are highly sophisticated and costly and do not catch much attention in the thumb rules.

Qualitative air flow modelling and analysis of data centre air conditioning as multiple jet array

This work identifies the importance of plenum pressure on the performance of the data centre. The present methodology followed in the industry considers the pressure drop across the tile as a dependant variable, but it is shown in this work that this is the only one independent variable that is responsible for the entire flow dynamics in the data centre, and any design or assessment procedure must consider the pressure difference across the tile as the primary independent variable. This concept is further explained by the studies on the effect of dampers on the flow characteristics. The dampers have found to introduce an additional pressure drop there by reducing the effective pressure drop across the tile. The effect of damper is to change the flow both in quantitative and qualitative aspects. But the effect of damper on the flow in the quantitative aspect is only considered while using the damper as an aid for capacity control. Results from the present study suggest that the use of dampers must be avoided in data centre and well designed tiles which give required flow rates must be used in the appropriate locations. In the present study the effect of hot air recirculation is studied with suitable assumptions. It identifies that, the pressure drop across the tile is a dominant parameter which governs the recirculation. The rack suction pressure of the hardware along with the pressure drop across the tile determines the point of recirculation in the cold aisle. The positioning of hardware in the racks play an important role in controlling the recirculation point. The present study is thus helpful in the design of data centre air flow, based on the theory of jets. The air flow can be modelled both quantitatively and qualitatively based on the results.

“Qualitative Air Flow Modelling And Analysis Of Data Centre Air Conditioning As Multiple Jet Array

In the present study the effect of hot air recirculation is studied with suitable assumptions. It identifies that, the pressure drop across the tile is a dominant parameter which governs the recirculation. The rack suction pressure of the hardware along with the pressure drop across the tile determines the point of recirculation in the cold aisle. The positioning of hardware in the racks play an important role in controlling the recirculation point. The present study is thus helpful in the design of data centre air flow, based on the theory of jets. The air flow can be modelled both quantitatively and qualitatively based on the results

Impact of sward type, cutting date and conditioning temperature on mass and energy flows in the integrated generation of solid fuel and biogas from semi-natural grassland

Energy production from biomass and the conservation of ecologically valuable grassland habitats are two important issues of agriculture today. The combination of a bioenergy production, which minimises environmental impacts and competition with food production for land with a conversion of semi-natural grasslands through new utilization alternatives for the biomass, led to the development of the IFBB process. Its basic principle is the separation of biomass into a liquid fraction (press fluid, PF) for the production of electric and thermal energy after anaerobic digestion to biogas and a solid fraction (press cake, PC) for the production of thermal energy through combustion. This study was undertaken to explore mass and energy flows as well as quality aspects of energy carriers within the IFBB process and determine their dependency on biomass-related and technical parameters. Two experiments were conducted, in which biomass from semi-natural grassland was conserved as silage and subjected to a hydrothermal conditioning and a subsequent mechanical dehydration with a screw press. Methane yield of the PF and the untreated silage was determined in anaerobic digestion experiments in batch fermenters at 37°C with a fermentation time of 13-15 and 27-35 days for the PF and the silage, respectively. Concentrations of dry matter (DM), ash, crude protein (CP), crude fibre (CF), ether extract (EE), neutral detergent fibre (NDF), acid detergent fibre (ADF), acid detergent ligning (ADL) and elements (K, Mg, Ca, Cl, N, S, P, C, H, N) were determined in the untreated biomass and the PC. Higher heating value (HHV) and ash softening temperature (AST) were calculated based on elemental concentration. Chemical composition of the PF and mass flows of all plant compounds into the PF were calculated. In the first experiment, biomass from five different semi-natural grassland swards (Arrhenaterion I and II, Caricion fuscae, Filipendulion ulmariae, Polygono-Trisetion) was harvested at one late sampling (19 July or 31 August) and ensiled. Each silage was subjected to three different temperature treatments (5°C, 60°C, 80°C) during hydrothermal conditioning. Based on observed methane yields and HHV as energy output parameters as well as literature-based and observed energy input parameters, energy and green house gas (GHG) balances were calculated for IFBB and two reference conversion processes, whole-crop digestion of untreated silage (WCD) and combustion of hay (CH). In the second experiment, biomass from one single semi-natural grassland sward (Arrhenaterion) was harvested at eight consecutive dates (27/04, 02/05, 09/05, 16/05, 24/05, 31/05, 11/06, 21/06) and ensiled. Each silage was subjected to six different treatments (no hydrothermal conditioning and hydrothermal conditioning at 10°C, 30°C, 50°C, 70°C, 90°C). Energy balance was calculated for IFBB and WCD. Multiple regression models were developed to predict mass flows, concentrations of elements in the PC, concentration of organic compounds in the PF and energy conversion efficiency of the IFBB process from temperature of hydrothermal conditioning as well as NDF and DM concentration in the silage. Results showed a relative reduction of ash and all elements detrimental for combustion in the PC compared to the untreated biomass of 20-90%. Reduction was highest for K and Cl and lowest for N. HHV of PC and untreated biomass were in a comparable range (17.8-19.5 MJ kg-1 DM), but AST of PC was higher (1156-1254°C). Methane yields of PF were higher compared to those of WCD when the biomass was harvested late (end of May and later) and in a comparable range when the biomass was harvested early and ranged from 332 to 458 LN kg-1 VS. Regarding energy and GHG balances, IFBB, with a net energy yield of 11.9-14.1 MWh ha-1, a conversion efficiency of 0.43-0.51, and GHG mitigation of 3.6-4.4 t CO2eq ha-1, performed better than WCD, but worse than CH. WCD produces thermal and electric energy with low efficiency, CH produces only thermal energy with a low quality solid fuel with high efficiency, IFBB produces thermal and electric energy with a solid fuel of high quality with medium efficiency. Regression models were able to predict target parameters with high accuracy (R2=0.70-0.99). The influence of increasing temperature of hydrothermal conditioning was an increase of mass flows, a decrease of element concentrations in the PC and a differing effect on energy conversion efficiency. The influence of increasing NDF concentration of the silage was a differing effect on mass flows, a decrease of element concentrations in the PC and an increase of energy conversion efficiency. The influence of increasing DM concentration of the silage was a decrease of mass flows, an increase of element concentrations in the PC and an increase of energy conversion efficiency. Based on the models an optimised IFBB process would be obtained with a medium temperature of hydrothermal conditioning (50°C), high NDF concentrations in the silage and medium DM concentrations of the silage.

Genetic influences on hypoxic conditioning

This paper addresses the relationship between noise-induced hearing loss (NIHL) and hypoxic conditioning prior to noise exposure. The study begins the process of determining the number and characteristic of the gene(s) involved in the cochlear hypoxic conditioning response.

The relation between the electroencephalogram and the ease of autonomic conditioning

This paper discusses the results of a study to determine a relationship between the EEG pattern and autonomic conditioning.