Moveable Wall Research Articles

Correction to: Exploration of water conveying carbon nanotubes, graphene, and copper nanoparticles on impermeable stagnant and moveable walls experiencing variable temperature: thermal analysis

Correction to: Exploration of water conveying carbon nanotubes, graphene, and copper nanoparticles on impermeable stagnant and moveable walls experiencing variable temperature: thermal analysis

Exploration of water conveying carbon nanotubes, graphene, and copper nanoparticles on impermeable stagnant and moveable walls experiencing variable temperature: thermal analysis

Exploration of water conveying carbon nanotubes, graphene, and copper nanoparticles on impermeable stagnant and moveable walls experiencing variable temperature: thermal analysis

Lighting Improvement and Space Flexibility using Moveable Walls

This article discusses design of possible connection system by moving the vertical and horizontal construction’ elements. The vertical and horizontal elements are applied to ensure comfortable indoor lighting comfort. This idea is part of sustainable low-technology strategy. The developed mobile facade technology aims to transmit sunlight into the space unimpeded, as well as to improve the building’ performance. This research is preliminary part of the design development in producing flexible space using movable wall and also the need to control sunlight by using dynamic facades. The research method uses application of modeling to create the desired shapes and prototypes for movement design. Applying multiple movable joints and various vertical or horizontal elements will improve lighting conditions. In addition, the application of a movable wall system into design can increase the indoor comfort without reducing the room function.Keywords: dynamic facades; indoor comfort; lighting improvement, moveable walls; space flexibility

Clariant launches catalyst R&D in Shanghai

This study compared three methods of removing mineral matter (washing) from coal: jigging coal particles in water using the Roben Jig, the float/sink method using traditional organic liquids (naptha, perchloroethylene, methylene bromide), and a full-sized industrial wash plant. Clean coal composites from six coal types (A, B, C, D, E, and F) were tested. All coals were washed using the Roben Jig and the float/sink method and seams E and F were also washed in an industrial wash plant. In each case, the Roben Jig was capable of producing a clean coal composites with coal quality characteristics (proximate analysis, FSI, S, calorific value, mineral analysis of ash, RoMax) very similar to that of the clean coal samples created by the organic liquids float/sink method and the industrial wash plant sample. The Gieseler fluidity and Ruhr dilatation values were lower in the traditional float/sink method where the coal was exposed to organic liquids. There was very little difference in the Sapozhnikov Y values and small differences in the G Caking Index values. All six coal types were carbonized in a sole-heated oven and CSR was tested. Comparing the CSRs for the clean samples created by the Roben Jig and organic liquids for coals A, B, C, and D, in four out of five cases the CSR from the organic liquids treated samples was higher (differences ranging from 2 to 8 points). Coals E and F were washed using all three methods and the samples prepared in the organic liquids had the highest CSRs (differences ranging from 3 to 7). The clean coal samples from Coal F were carbonized in a moveable wall oven. CSRs ranged from 66.7 to 69.2, with the plant sample having the highest value. ASTM stability values ranged from 51.7 to 57.3 with the lowest value resulting from the organic liquids washed sample.

Preparation of clean coal samples using the Roben Jig

This study compared three methods of removing mineral matter (washing) from coal: jigging coal particles in water using the Roben Jig, the float/sink method using traditional organic liquids (naptha, perchloroethylene, methylene bromide), and a full-sized industrial wash plant. Clean coal composites from six coal types (A, B, C, D, E, and F) were tested. All coals were washed using the Roben Jig and the float/sink method and seams E and F were also washed in an industrial wash plant. In each case, the Roben Jig was capable of producing a clean coal composites with coal quality characteristics (proximate analysis, FSI, S, calorific value, mineral analysis of ash, RoMax) very similar to that of the clean coal samples created by the organic liquids float/sink method and the industrial wash plant sample. The Gieseler fluidity and Ruhr dilatation values were lower in the traditional float/sink method where the coal was exposed to organic liquids. There was very little difference in the Sapozhnikov Y values and small differences in the G Caking Index values. All six coal types were carbonized in a sole-heated oven and CSR was tested. Comparing the CSRs for the clean samples created by the Roben Jig and organic liquids for coals A, B, C, and D, in four out of five cases the CSR from the organic liquids treated samples was higher (differences ranging from 2 to 8 points). Coals E and F were washed using all three methods and the samples prepared in the organic liquids had the highest CSRs (differences ranging from 3 to 7). The clean coal samples from Coal F were carbonized in a moveable wall oven. CSRs ranged from 66.7 to 69.2, with the plant sample having the highest value. ASTM stability values ranged from 51.7 to 57.3 with the lowest value resulting from the organic liquids washed sample.

Analysis of Earth Pressure Variation for Partial Displacement of Retaining Wall

Parts of the retaining wall might produce displacement under different load conditions. The moveable wall could impact the adjacent fixed wall, mainly reflecting on the variation of earth pressure and formation of the soil arching effect. This paper conducted the horizontal trap-door test to explore the variation of active earth pressure caused by partial displacement of the retaining wall. Different trap-door width and three displacement modes were addressed as the influence factors. The results indicated that the horizontal soil arching effect was generated after the active displacement of the trap-door and the soil pressure was redistributed. The distribution of lateral soil pressure was approximately an “inverted bell” curve. For trap-door widths of 20 cm, 30 cm, and 40 cm, a secondary soil arching effect appeared in the test. The relationship between lateral earth pressure and displacement was different with the traditional limited theory due to the influence of the soil arching effect. The variation curve of earth pressure corresponding to displacement could be divided into three stages. In addition, the distribution of earth pressure along the trap-door height was non-linear. Trap-door width can significantly influence the maximum earth pressure on the fixed wall and the range where pressure changes. Finally, the effect of load sharing was explored and found to be related with displacement and width of trap-door as well as the displacement mode.

Experimental determination of the influence of additives on shrinkage in self-compacting concrete

The paper deals with the influence of additives on the progress of shrinkage and mass losses in self-compacting concrete. Limestone and fly ash at varying amounts were used as an additive in the production of four types of self-compacting concrete. Volume changes were observed from an early stage of setting (the measurement was commenced within 1 hour of mixing) using shrinkage drains with a moveable wall, followed by a long-term manual measurement using an external strain gauge. For the first 48 hours the volume-change measurement was continuous, and for the next few months it was performed manually. Mass losses were determined simultaneously with shrinkage – during the first 48 hours by weighing on a special weighing table capable of continuous recording, and manually afterwards.

Application Research of an Efficient and Stable Boundary Processing Method for the SPH Method

The boundary truncation of the kernel function affects the numerical accuracy and calculation stability of the smooth particle hydrodynamics (SPH) method and has been one of the key research fields for this method. In this paper, an efficient and stable boundary processing method for the SPH method was introduced by adopting an improved boundary interpolation method (i.e., the improved Shepard method) which needs only the sum of direct accumulation for fixed-boundary particles to improve the numerical stability and computational efficiency of the fixed ghost particle method. The improvement effect of the method was demonstrated by comparing it with different interpolation methods using the cases of still water, a wave generated by dam-breaking, and a solitary wave attacking problem with fixed walls and a moveable wall. The results showed that the new boundary processing method for SPH can help remarkably improve the efficiency of calculation and reduce the oscillations of pressure when simulating various flows.

Assessment of flexible features in the design of event centres in Minna, Niger state Nigeria

Flexibility overtime has been known to enhance the peculiarity of a space, making spaces adaptable to multipurpose use, without altering the functional requirements. The design features and techniques that allow for changing situations in the use and operation of spaces are the focus of this paper. Components such as walls, floors and roofs are the design features that affect space in any building. Event centres being hubs for cultural and social activities, attract an unpredictable population, hence the need for flexible venues for event centres which are fast becoming stable and developing features of any city. The study assessed available event centres and the design features used to achieve flexibility, examining their adaptation to inadequacy of event spaces in selected event centres in Minna Niger state. Observation schedules was used as instrument to obtain data, the data collected was then analysed using Microsoft excel. It was observed from the study that all event centres had adaptability as their flexible design approach and this is as a result of the use of large open spaces, however 80% of event centres in Minna, Niger state failed to have flexible design features. The 20% that provided few of these features used curtain as flexible design elements. The paper recommended that design features for flexibility such as moveable walls, retractable roofs and sitting should be used in event centre designs to achieve an effective flexible design. Keywords : Adaptation, Design features, Event centre, Flexibility

Experimental Investigations to Use Splash Lubrication for High-Speed Gears

In order to use electric motors which run up to 40,000 rpm in future automotive applications, this study aims to experimentally investigate if splash lubrication technique is worth considering for high-speed gears, i.e., for tangential gear speed up to 60 m/s. To this end, a specific test rig has been used to operate a single spur or helical gear in various operating conditions (lubricant, oil sump volume, temperature, etc.). Churning loss is measured and, as the fraction of air in the lubricant (namely, oil aeration) can be influential on this source of dissipation, a specific sensor is also employed for online monitoring of oil sump aeration. By inserting some moveable walls in the gearbox, it is demonstrated that churning losses and oil aeration can be significantly reduced by mounting these flanges at an appropriate distance to the gear lateral faces. Based on dimensional analysis, an engineering criterion is proposed to properly choose the clearance between the tested gear and the flanges.

RF-MEMS Tuned GaN HEMT based Cavity Oscillator for X-band

This letter presents a radio frequency micro-electromechanical systems (RF-MEMS) tuned cavity oscillator for X-band. The active part of the oscillator is implemented in GaN-HEMT MMIC technology. The RF-MEMS-switches are realized on a quartz substrate that is surface mounted on a low loss PCB. The PCB is intruded in an aluminum cavity acting as an electrically moveable wall. For a three-row RF-MEMS setup, a tuning range of 5 % around an oscillation frequency of 10 GHz is demonstrated in measurements. The phase noise is as low as −140 dBc/Hz to −129 dBc/Hz at 100 kHz from the carrier, depending on the configuration of the RF-MEMS.

Natural whisker-guided behavior by head-fixed mice in tactile virtual reality.

During many natural behaviors the relevant sensory stimuli and motor outputs are difficult to quantify. Furthermore, the high dimensionality of the space of possible stimuli and movements compounds the problem of experimental control. Head fixation facilitates stimulus control and movement tracking, and can be combined with techniques for recording and manipulating neural activity. However, head-fixed mouse behaviors are typically trained through extensive instrumental conditioning. Here we present a whisker-based, tactile virtual reality system for head-fixed mice running on a spherical treadmill. Head-fixed mice displayed natural movements, including running and rhythmic whisking at 16 Hz. Whisking was centered on a set point that changed in concert with running so that more protracted whisking was correlated with faster running. During turning, whiskers moved in an asymmetric manner, with more retracted whisker positions in the turn direction and protracted whisker movements on the other side. Under some conditions, whisker movements were phase-coupled to strides. We simulated a virtual reality tactile corridor, consisting of two moveable walls controlled in a closed-loop by running speed and direction. Mice used their whiskers to track the walls of the winding corridor without training. Whisker curvature changes, which cause forces in the sensory follicles at the base of the whiskers, were tightly coupled to distance from the walls. Our behavioral system allows for precise control of sensorimotor variables during natural tactile navigation.

Impact of Oven Bulk Density and Coking Rate on Stamp-Charged Metallurgical Coke Structural Properties

Coke samples obtained by carbonizing a commercial coal blend in a pilot-scale moveable wall slot-oven were studied to evaluate the influence of oven bulk density and coking rate on coke structural quality. Coke samples were investigated using the coke strength after reaction (CSR) test, gas adsorption techniques, optical microscopy, and X-ray diffraction analyses. The results show that an increase in oven bulk density and coking rate led to an increase in CSR, a phenomenon attributed to enhanced coal particle adhesion and improved plasticity during the plastic stage. Surface area, total porosity, pore area, and cell wall measurements indicate that the compact nature of coal charge under high oven bulk density and accelerated events under a rapid coking rate result in limited pore structural development, leading to a less porous coke. An increase in coke oven bulk density resulted in the growth of carbon forms and also improved the degree of crystallization. However, the proportion of less-reactive carbon ...

Small scale determination of metallurgical coke CSR

Coke Strength after Reaction (CSR) and the concomitant Coke Reactivity Index (CRI) are useful parameters for assessing the behavior of coke in blast furnace. To measure CSR and CRI of the resultant coke from a particular metallurgical coal or blend, a pilot scale oven test for producing appropriate industrial grade coke for measurements is unavoidable. If the quantity of coal sample available is not sufficient for pilot scale oven test, CSR measurement of the resultant coke is normally not possible. CanmetENERGY has developed a procedure for producing coke to allow CSR measurement involving relatively small amounts of coal sample (∼15kg). The procedure involves producing semi-coke using the Sole Heated Oven in accordance with ASTM standard D2014-97 (2004). In the Sole Heated Oven test the coal sample is heated only from the bottom (the sole) up to 950°C with the top of the oven charge rising to 500°C over a period of 6–7h. The resulting semi-coke is quenched (either wet or dry) and subsequently reheated to 1100°C under nitrogen for 1h. CSR and CRI are measured using the coke produced using this procedure. To demonstrate the validity of CSR and CRI measured using this approach, identical coal blends were carbonized concurrently using the CanmetENERGY pilot scale moveable wall oven (460mm wide, 350kg capacity) and the procedures mentioned above. CSR and CRI of the cokes produced by these two approaches were compared. Statistical analysis and coke textual analysis were performed to demonstrate the relevance of this novel approach on CSR determination.

Design of built environments to accommodate mobility scooter users: part II

Purpose. Accessibility standards for wheeled mobility devices currently use a 1.5 m turning circle, designed to accommodate manual wheelchairs. Scooters are less manoeuvrable than wheelchairs, so allowing a full turning circle would require too much space. Instead, we propose using a rectangle that provides space for a three-point turn. Here, we determine the area requirements of this approach.Method. For rectangular ‘rooms’ of varying aspect ratios, we measured the minimum dimensions in which two four-wheeled scooters (the Celebrity-X and Fortress-1700), which combine good outdoor performance with reasonable indoor manoeuvrability, could enter the space, perform a three-point turn and exit. Moveable Styrofoam walls defined each ‘room’, and a doorway was located either near the corner of the space or in the middle of one wall. ‘Room’ size was decreased until our expert driver could no longer perform the manoeuvre.Results. Compared to the area required for a turning circle, 42–54% savings were achieved. Relative to existing requirements, 53–95% more space is required to accommodate the Celebrity-X; 173–223% increases are necessary for the Fortress-1700.Conclusions. When accommodating four-wheeled scooters, our proposed three-point turn definition would require more space than the current standards, but considerably less than if a full turning circle were used.

AN ADAPTIVE CAVITY SETUP FOR ACCURATE MEASUREMENTS OF COMPLEX DIELECTRIC PERMITTIVITY

In order to enhance the accuracy of the complex permittivity data employed in Ground Penetrating Radar (GPR) techniques, an adaptive cavity setup is presented. The use of moveable walls permits to relax the mechanical constraints on the sample dimensions so that it can be employed also in complicate measurement condition as, for example, in the case of wet samples. Moreover, exploiting the cavity resonance phenomenon, low loss materials, such as some type of marbles, can be accurately evaluated. The numerical characterization, the parametric analyses and the L-band measurement results show the validity and the reliability of this conflguration.

Effect of Concentration and Hydration on Restriction of Albumin by Lung Interstitium

In previous studies, the flow of albumin solution through hydrated lung interstitial segments was higher than a prior flow of Ringer solution (A. Tajaddinni et al., 1994, J. Appl. Physiol. 76, 578–583). We wondered whether this effect was caused by an increased pore size. We measured the flow of albumin solutions through interstitial segments subjected to a driving pressure of 5 cm H2O and various mean interstitial pressures (Pif). The ratio of albumin concentration (Calb) of the output solution to that of the input solution (Cout/Cin, sieving ratio) was measured using tracer 125I-albumin. At normal hydration (0 cm H2O Pif), Cout/Cin was minimal (0.6) with the flow of Ringer solution, increased to 0.8 with the flow of 5 g/dl albumin solution, and increased to 1 with increased hydration at 15 cm H2O Pif. We modeled the interstitium as a membrane subjected to flows of high Peclet numbers. Accordingly, the albumin reflection coefficient [ς = 1 − (Cout/Cin)] at 0 cm H2O Pif was 0.4 with the flow of Ringer solution and decreased to 0 at 5 g/dl Calb and 15 cm H2O Pif. This behavior suggests that the flow of albumin occurred through interstitial pores that increased in size as either Calb or hydration increased. We conceive of an interstitium that consists of pores with permeable moveable walls across which osmotic interaction occurs between the pore liquid and the surrounding tissue.

98/03557 Oxidative semicoking of coal in fluidized bed

Coke Strength after Reaction (CSR) and the concomitant Coke Reactivity Index (CRI) are useful parameters for assessing the behavior of coke in blast furnace. To measure CSR and CRI of the resultant coke from a particular metallurgical coal or blend, a pilot scale oven test for producing appropriate industrial grade coke for measurements is unavoidable. If the quantity of coal sample available is not sufficient for pilot scale oven test, CSR measurement of the resultant coke is normally not possible. CanmetENERGY has developed a procedure for producing coke to allow CSR measurement involving relatively small amounts of coal sample (∼15 kg). The procedure involves producing semi-coke using the Sole Heated Oven in accordance with ASTM standard D2014-97 (2004). In the Sole Heated Oven test the coal sample is heated only from the bottom (the sole) up to 950 °C with the top of the oven charge rising to 500 °C over a period of 6–7 h. The resulting semi-coke is quenched (either wet or dry) and subsequently reheated to 1100 °C under nitrogen for 1 h. CSR and CRI are measured using the coke produced using this procedure. To demonstrate the validity of CSR and CRI measured using this approach, identical coal blends were carbonized concurrently using the CanmetENERGY pilot scale moveable wall oven (460 mm wide, 350 kg capacity) and the procedures mentioned above. CSR and CRI of the cokes produced by these two approaches were compared. Statistical analysis and coke textual analysis were performed to demonstrate the relevance of this novel approach on CSR determination.

98/03555 Method of estimation and characteristics for coke heat quantities of coking coal

Coke Strength after Reaction (CSR) and the concomitant Coke Reactivity Index (CRI) are useful parameters for assessing the behavior of coke in blast furnace. To measure CSR and CRI of the resultant coke from a particular metallurgical coal or blend, a pilot scale oven test for producing appropriate industrial grade coke for measurements is unavoidable. If the quantity of coal sample available is not sufficient for pilot scale oven test, CSR measurement of the resultant coke is normally not possible. CanmetENERGY has developed a procedure for producing coke to allow CSR measurement involving relatively small amounts of coal sample (∼15 kg). The procedure involves producing semi-coke using the Sole Heated Oven in accordance with ASTM standard D2014-97 (2004). In the Sole Heated Oven test the coal sample is heated only from the bottom (the sole) up to 950 °C with the top of the oven charge rising to 500 °C over a period of 6–7 h. The resulting semi-coke is quenched (either wet or dry) and subsequently reheated to 1100 °C under nitrogen for 1 h. CSR and CRI are measured using the coke produced using this procedure. To demonstrate the validity of CSR and CRI measured using this approach, identical coal blends were carbonized concurrently using the CanmetENERGY pilot scale moveable wall oven (460 mm wide, 350 kg capacity) and the procedures mentioned above. CSR and CRI of the cokes produced by these two approaches were compared. Statistical analysis and coke textual analysis were performed to demonstrate the relevance of this novel approach on CSR determination.

Inverse Dynamics in the Classical Fermi Accelerator

The motion of a particle constrained to move between two walls one of which is moveable is solved. We determine analytically the effective forces that act on the particle or on the moveable wall. The quantal version of the solution is briefly discussed.