Internal Spacer Research Articles

Eye movements follow the dynamic shifts of attention through serial order in verbal working memory

How are arbitrary sequences of verbal information retained and manipulated in working memory? Increasing evidence suggests that serial order in verbal WM is spatially coded and that spatial attention is involved in access and retrieval. Based on the idea that brain areas controlling spatial attention are also involved in oculomotor control, we used eye tracking to reveal how the spatial structure of serial order information is accessed in verbal working memory. In two experiments, participants memorized a sequence of auditory words in the correct order. While their eye movements were being measured, they named the memorized items in a self-determined order in Experiment 1 and in a cued order in Experiment 2. We tested the hypothesis that serial order in verbal working memory interacts with the spatial attention system whereby gaze patterns in visual space closely follow attentional shifts in the internal space of working memory. In both experiments, we found that the gaze shifts in visual space correlated with the spatial shifts of attention along the left-to-right one-dimensional mapping of serial order positions in verbal WM. These findings suggest that spatial attention is employed for dynamically searching through verbal WM and that eye movements reflect the spontaneous association of order and space even in the absence of visuospatial input.

Non-minimal elliptic threefolds at infinite distance II: asymptotic physics

We interpret infinite-distance limits in the complex structure moduli space of F-theory compactifications to six dimensions in the light of general ideas in quantum gravity. The limits we focus on arise from non-minimal singularities in the elliptic fiber over curves in a Hirzebruch surface base, which do not admit a crepant resolution. Such degenerations take place along infinite directions in the non-perturbative brane moduli space in F-theory. A blow-up procedure, detailed generally in Part I of this project [1], gives rise to an internal space consisting of a union of log Calabi-Yau threefolds glued together along their boundaries. We geometrically classify the resulting configurations for genus-zero single infinite-distance limits. Special emphasis is put on the structure of singular fibers in codimension zero and one. As our main result, we interpret the central fiber of these degenerations as endpoints of a decompactification limit with six-dimensional defects. The conclusions rely on an adiabatic limit to gain information on the asymptotically massless states from the structure of vanishing cycles. We also compare our analysis to the heterotic dual description where available. Our findings are in agreement with general expectations from quantum gravity and provide further evidence for the Emergent String Conjecture.

A Ni–N–C catalyst for CO2 electroreduction based on the MOF@MOF configuration exhibiting wide active reaction sites

Decoupling the internal electron transfer space from the external active sites maximizes the reaction while keeping Ni as a single atom. Also, the catalyst core's superhydrophobic characteristics maintain the inner aerophilic environment.

Spatial confinement of MoS2 nanoparticles in jellyfish-inspired open-mouthed spheres for high-capacity and ultrafast-rate sodium-ion capture

Rational nanoscale structure engineering of electroactive nanoarchitecture is a very promising strategy for designing advanced capacitive deionization (CDI) materials. Herein, inspired by jellyfish physiological structure, open-mouthed MoS2/C hierarchical porous spheres were fabricated via direct-spray pyrolysis by adopting a strategy of coupling defective MoS2 with locally conductive network graphene quantum dots. Such a well-developed open-mouthed interconnected porous structure significantly stimulated the permeation of electrolyte ion the deep internal spaces of electrode, facilitated fast ion diffusion and provided abundant electrochemical adsorption sites, endowing the MoS2/C electrode with a remarkable desalination capacity of 118.83 mg g−1, an impressively rapid desalination rate of 51.35 mg g−1 min−1, and a good long-term cycle stability of 82 % after 50 cycles. This work inspires the design hierarchically porous composite materials with unique micro-nanostructures, offering a new viable route for the continuous and efficient production of CDI electrode materials.

A roller-type triboelectric nanogenerator based on rotational friction between wool and stacked interfaces for omnidirectional wind energy harvesting.

It is urgently desired to develop high-performance wind energy collectors to power numerous microelectronic devices along with the Internet of Things (IoT). A roller-type triboelectric nanogenerator (R-TENG) based on rotational friction between wool and stacked interfaces is proposed and efficiently used for harvesting wind energy. Wool, an electropositive and flexible material, is utilized in the design, effectively reducing abrasion on the contact surface and adjusting the output in response to varying compression levels. The conductive layer greatly enhances the output performance, which produces more induced charge by stacking different triboelectric materials in a particular order. By adding bottom power generation units, the internal space of the unit can be fully utilized to improve its energy conversion efficiency. At 900 rpm of the motor, the instantaneous open-circuit voltage (VOC), short-circuit current (ISC), and transferred charge (QSC) of the R-TENG can reach 1504 V, 67.24 μA and 157.4 nC, respectively. After connection to a load via a rectifier bridge, the R-TENG has a maximum power output of 14.58 mW and an instantaneous power density of 11.7 W m-3. In laboratory wind energy harvesting experiments, the design can easily drive at least 720 LEDs and charge a 2000 μF capacitor up to about 1.5 V in 78 s. In practice, the R-TENG can collect natural wind on windy seashores and moving vehicles to charge capacitors and successfully drive small electronic devices in real time. The experimental results indicate that the stacked PTFE/FKM/Wool R-TENG exhibits considerable output performance, making it a promising solution for efficiently capturing wind energy from all directions.

PRINCIPLES OF CIRCULATION AND MOVEMENT CONFIGURATIONS IN HOSPITAL DESIGN

Circulation paths can be defined as invisible threads linking internal and external spaces within a building relative to where a person is and the intended final destination. Various studies exist in the need to further understand the relationship between circulation and way-finding, particularly in hospital and healthcare buildings. In this study, a practical approach to hospital circulation design is presented to combine the principles of circulation as a design tool for layout configurations in the design of hospitals. This paper presents Circulation Elements as layers of flow that outline the movement paths within buildings. The study reviewed already established fundamental elements for circulation studies that are notable in architectural philosophies as major components for the way-finding process as it affects circulation in buildings. It further reviewed existing circulation systems to identify the potential patterns of circulation used in modern-day hospital buildings. These circulation principles were finally adopted in the conceptual design of a typical hospital building to justify its applicability. Analysis of the designed hospital circulation system is evaluated using VGA (visibility graph analysis) to identify the significance of carriage pathway sizes in improving visibility fields for indoor way-finding processes. The VGA analysis identified the ease of wayfinding and movement as dependent on the size of circulation spaces. This VGA method of analysis can be adopted by architects and designers for preliminary analysis of carriageways relative to circulation configuration during the design process to ensure improvement of circulation efficiency and way-finding.

‘A New Trend in Store Design’

In 1945 Pittsburgh Plate Glass Company released a portfolio of speculative designs for store fronts and retail interiors featuring glass. Titled There is a New Trend in Store Design, it was directed at designers and architects, and, through them, potential customers for their range of products. Pittsburgh Plate Glass Company was just one among many building material manufacturers competing for market share in the United States of America following World War II. This essay demonstrates how a set of unbuilt retail designs that were never intended to be constructed can illuminate prevailing trends of design and the socio-political, economic, and cultural contexts that informed their production. By examining drawings of unbuilt interiors, this essay establishes the types of contextual information that can be gleaned through an interpretive exploration of such works, including economic and social conditions, architectural and retail design trends, typical drawing modes and techniques, developments in building materials and practices, and approaches to advertising. Through an analysis of the historical circumstances that underpinned the portfolio’s production, it is established that unbuilt design drawings contain clues that foreshadow built designs to come, and by exploring these design ideas alongside the designers’ statements, a richer understanding of the subject of the designs, in this case, post-war retail premises, may be uncovered. This essay explores not only the use made of unbuilt interiors as marketing material but also the role of the glass and interior in the expression of Modernist ideas. Specifically, it reveals the importance of glass in the Modern retail interior, as it developed from being viewed solely as an enclosed internal space into becoming a critical part of the store’s ‘open front’, reconceptualising the fa.ade condition of architecture in the commercial context of urban retail spaces in post-war North America and marking this period as a turning point in design history.

Research on Structural Optimization and Excitation Control Method Using a Two-Dimensional OWPT System for Capsule Robots Based on Non-Equivalent Coils.

The rapid development of wireless power transfer (WPT) technology has provided new avenues for supplying continuous and stable power to capsule robots. In this article, we propose a two-dimensional omnidirectional wireless power transfer (OWPT) system, which enables power to be transmitted effectively in multiple spatial directions. This system features a three-dimensional transmitting structure with a Helmholtz coil and saddle coil pairs, combined with a one-dimensional receiving structure. This design provides sufficient internal space, accommodating patients of various body types. Based on the magnetic field calculation and finite element analysis, the saddle coil structure is optimized to enhance magnetic field uniformity; to achieve a two-dimensional rotating magnetic field, a phase difference control method for the excitation signal is developed through the analysis of circuit topology and quantitative synthesis of non-equivalent magnetic field vectors. Finally, an experimental prototype is built, and the experimental results show that the one-dimensional transmitting coil achieves a minimum received voltage stability of 94.5% across different positions. When the three-dimensional transmitting coils operate together, a two-dimensional rotating magnetic field in the plane is achieved at the origin, providing a minimum received power of 550 mW with a voltage fluctuation rate of 7.68%.

Constructing High-Performance Yarn-Shaped Electrodes via Twisting-after-Coating Technique for Weavable Seawater Battery.

Seawater batteries (SWBs) are green aqueous power sources with great potential in marine applications. So far, SWBs are mainly built on rigid substrates, which hinders their adaptability to marine textile applications. Herein, we constructed a rechargeable yarn-shaped SWB consisting of nickel hexacyanoferrate (Ni-HCF)-modified carbon yarn (positive electrode), glass fiber diaphragm, and polyimide (PI)-modified carbon yarn (negative electrode). To improve the performance of carbon yarn-based electrodes, a twisting-after-coating (TAC) technique was developed to replace the conventional twisting-before-coating (TBC) technique for immobilizing active materials. The TAC technique could fully utilize the internal spaces between adjacent fibers in carbon yarns and avoid the accumulation of active materials on the electrode surface. Taking the Ni-HCF-modified electrode as an example, its maximum specific capacity could reach 64.2 mAh/g, significantly higher than that (54.5 mAh/g) of the electrode prepared by the TBC technique. The improvement could be explained by embedding the active materials in the yarn and the close contact between the active materials and the carbon fibers caused by the twisting. The Ni-HCF-modified and PI-modified yarn electrodes prepared by the TAC technique were assembled to construct a yarn-shaped SWB that exhibits good rate performance, excellent flexibility, and high cycling stability. The yarn-shaped SWBs were further woven into a fishing net-like textile. After being soaked with seawater and electrically charged, the textile can successfully power a light panel composed of 10 light-emitting diodes, demonstrating the potential of yarn-shaped SWBs for power supply in marine.

Customer Satisfaction and Service Quality Assessment of Nepal Yatayat Public Buses: A Statistical Analysis of Passenger Perceptions

Background: Public transportation is vital for urban mobility, offering affordable and accessible commuting options, especially in densely populated regions. In Nepal, public buses serve a broad demographic, and understanding passenger satisfaction with services like Nepal Yatayat can provide insights for service improvements. Objective: This study aims to analyze customer satisfaction with the Nepal Yatayat bus service, examining factors such as comfort, safety, cleanliness, punctuality, and overall service reliability. The goal is to identify key areas for improvement to enhance user experience and promote public transport use. Methods: The study utilized a quantitative approach through a structured questionnaire distributed to 92 respondents. Data analysis was conducted using SPSS software, where various statistical tools such as correlation and reliability analysis assessed relationships between demographic factors and satisfaction variables. Findings: The majority of respondents were young adults aged 18-24 (75.8%), predominantly male (65.9%), with a significant portion holding bachelor's degrees (49.5%) and most being unemployed (61.8%). 59.4% of respondents expressed discomfort with bus seating and internal space arrangements, while 78.1% reported dissatisfaction or uncertainty about cleanliness standards. About 42.9% felt safe on Nepal Yatayat buses, while 30.8% were dissatisfied with punctuality. 37.7% of respondents rated staff behavior poorly, indicating a need for improvement in professionalism. Overcrowding was a significant concern, with 67.1% agreeing that buses were frequently crowded, and 45.1% believed the bus station locations were appropriate. : Reliability was rated as medium by 77.2% of respondents, with moderate recommendations for the service among users (40.7% likely to recommend). Conclusion: The analysis reveals that Nepal Yatayat requires improvements in comfort, cleanliness, safety, and punctuality to enhance passenger satisfaction. Crowding and staff professionalism are also key areas where service modifications could significantly impact commuter perceptions. Novelty: This study provides a detailed and empirical assessment of passenger satisfaction specifically with Nepal Yatayat, addressing service dimensions such as comfort, cleanliness, safety, and route effectiveness, previously underexplored in public transport studies within Nepal.

Daylighting in modernist educational architecture in the United Kingdom

The consideration of environmental quality in buildings became prominent in the Modernist movement in the UK and on the international scene, after the Second World War, including the emphasis on daylight access, particularly in educational buildings. The Marylebone building of the University of Westminster (1970s), in central London, is an example of this architectural trend. With rooflights, tilted ceilings, double height spaces and other features, this is a late modernist example of optimised daylighting design in educational buildings in the United Kingdom. However, the north-south symmetrical approach to the rooflights and the distribution of internal spaces raise questions about the efficiency of daylight. Hence, the aim of this technical study was to assess the daylight performance of the Marylebone building, considering its original and current layouts, with the use of Climate-Based Daylight Modelling (CBDM). Performance criteria included Useful Daylight Illuminance (UDI), Daylight Factor (DF), Illuminance levels and Glare Probability. Among the main results, it was found the achievement of the minimum threshold of 300 lux for most of the year (equivalent to 2% DF). Risks of glare were identified closer to windows and under the rooflights on the south side. It is concluded that the daylight strategies of the project were attuned to the activities and furniture layout of the atelier studio of the 1970s but not fully suitable for the use of personal computers that replaced the drawing boards in the 1990s, due to the excessive illuminance levels and penetration of direct solar radiation, leading to the recent insertion of internal blinds.

Numerical Optimization of Thermal Performance Using Kriging Method in a Propulsion Motor

Compared to traditional radial flux permanent magnet motors, axial flux permanent magnet (AFPM) motors face challenges in air-cooled internal space design due to their compact internal structure. A separate, independent liquid cooling system is applied to effectively dissipate heat generated within the stator core and windings. This research employs computational fluid dynamics (CFD) and the Kriging method to analyze the thermal performance and pressure characteristics of AFPM motors with outer-rotating housings. The aim is to derive a thermal performance map and optimal design parameters for the cooling passage. For efficient analysis, the motor was simplified into a simple thermal model that includes the coolant passage, stator hub, core, and stator coil. CFD was adopted to predict the temperature distribution of significant components, focusing on coolant channel diameter and flow rate as parameters. The Kriging method was applied to derive a thermal performance map, and optimal design parameters were proposed using a utility function. Results indicate that increasing the coolant channel diameter by 0.9 mm and flow rate by 0.2 lpm reduces the hydraulic power required for coolant circulation by 62.1%. The maximum winding temperature stays within the permissible limit of 109 °C, and the thermal performance index improves by 49.3%.

Nanotechnology and its role in raising the efficiency of the internal environment in negative patient isolation rooms in Egyptian hospitals-Evidence-Proofs

Despite the development of nanotechnology materials and the discovery of new properties that have contributed to improving various fields, especially the field of architecture, as it has been able to harness some materials to serve the architectural environment, whether internal or external to buildings, and combat the challenges that hinder the harmony of buildings with the natural external environment. Among the most important of these materials are coatings, which of course have an effective role in buildings, especially healthcare buildings, as nanotechnology has been able to produce materials that help support the internal environment of patient isolation rooms to combat the spread of infection and the spread of bacteria and fungi within that environment, which poses a clear danger to the patient and the medical staff responsible for his care. Despite all this, there is controversy over the effectiveness of these materials in that they are useless and similar to their counterparts from traditional materials. Here comes the role of the research to prove through experiments the effectiveness and validity of nanotechnology materials techniques and their role in combating infection in the internal space of patient isolation rooms, and also combating the heat flow through the outer shell to the patient isolation room, which increases the aggravation of bacterial infection particles in the spaces

Optimized impeller hydraulic performance of submersible drainage pumps: An experimental study

Optimizing the hydraulic efficiency of submersible drainage pumps (SDPs) is crucial for energy conservation and performance enhancement, especially in emergency applications. Therefore, this study aims to develop an energy-efficient SDP by designing an optimized impeller model using a numerical scheme and introducing a flow balance block (FBB) as an alternative to modifying the pump casing, thereby reducing internal space and improving performance. Experimental validation of the optimized impeller and FBB was conducted by comparing their performance with the original pump model. The results demonstrated that the optimized impeller increased efficiency by 3.35% at a flow rate of 0.195 m3/min, with an overall average efficiency improvement of 2.33%. Additionally, when the optimized impeller and FBB were combined, the pump's efficiency was further enhanced by 5%, and the flow rate increased by approximately 10%. The study also proposed that the tap bolt method is more effective for installing the FBB than the silicone attaching method. This research provides a comprehensive experimental approach to improving SDP efficiency and offers valuable insights for future pump optimization.

Application of quasicrystals to data processing

Abstract We propose a data processing method based on properties of quasicrystals and apply it to bitmap images. The method uses the mapping between the physical and internal spaces of a quasi-crystal to uniformly distribute the part of data that is lost in the transmitting or storing processes. At the same time, it is possible to unambiguously restore the rest of the data. The main advantages are strict aperiodicity of discrete sets and everywhere discontinuous property of the mapping as well as the speed of computation, simplicity of implementation and a straightforward possibility of extending the method to encryption of higher dimensional data. Several examples of construction of quasicrystals and examples of image processing are given.

Design of Control Strategies for Electric Actuators in 155mm

Abstract The performance of electromagnetic servo actuators as the control execution mechanism for guided projectiles plays a crucial role in the control system of guided projectiles. Due to the limited internal space of correction projectiles and the need to adapt to high-speed rotation, high overload, and small volume environments, the structure, control, and drive circuits of the electromagnetic servo actuators should be miniaturized as much as possible while meeting the requirements and control accuracy. This paper introduces the principle design of the motor drive and control circuit. A permanent magnet synchronous motor is adopted according to the characteristics of the required electromagnetic servo actuators. The model of the permanent magnet synchronous motor is studied, and based on the extended Kalman filter state observer, the estimation of the motor rotor position and speed is conducted. Subsequently, closed-loop vector control simulations of current, speed, and position are performed using Matlab/Simulink to evaluate the control strategy’s effectiveness in actual 155mm correction projectile payloads. This research can provide beneficial reference and guidance for the optimization of electromagnetic servo actuators in practical applications.

Assessment of the lethal effect of a 500 kg deep-earth penetrating warhead striking underground confined space

Abstract As a priority military facility, underground constructions are high-value targets for earth-penetrating warheads. The lethal effect is different from that of open areas due to the confined internal space. In this study, numerical simulation and theoretical calculation are used to quantitatively and comparatively evaluate the performance of a 500-kg deep earth penetrating warhead charged with TNT, PBXN-109, and AFX-757 in a specific underground fortification. This evaluation considers the lethality of the shock wave, thermal effects, and case fragments, and the experimental data verify the reliability of the simulation results. Additionally, a three-segment simplified model is used to analyse the percentage of detonation energy for each segment and the main fragments generation ratio of the 500-kg deep earth penetrating warhead’s case. The results show that, for the shock wave, the overpressure peak at the same distance from the detonation centre is up to 7 times higher due to wall reflections, and AFX-757 has the most significant shockwave effect. For the thermal effect, AFX-757 has the highest burst temperature, followed by PBXN-109. The high temperature in the confined space lasts longer, and the damage caused by thermal effects cannot be ignored. For fragments, theoretical calculations and numerical simulations were used to determine the proportion of detonation energy in each part of the case. It was concluded that for high-velocity deep penetration warheads, the fragments generated are mainly concentrated in the middle cylindrical section. The results of this study can provide guidance for the design of earth-penetrating warheads, the damage assessment of confined space, and the designation of engineering protection standards.

Conductive Modification of Activated Carbon Fiber Cloths via Electrophoretic Deposition for Cathode in Lithium‐Ion Capacitor

AbstractWith the growing demand for high performance energy storage devices, the advanced manufacturing technology of electrodes, which is a crucial component, has become increasingly essential in academic research and industrial applications. Activated carbon fiber cloth (ACFC) is a promising candidate for lithium‐ion capacitor (LIC) electrodes due to its abundant internal space and pores. However, the wider application of ACFC is restricted by its inferior conductivity. The conventional coating process is costly in terms of both materials and time and is only applicable to surface treatment with limitations in treating shaped substrate such as ACFCs. To overcome the applications obstacles of ACFC in batteries and capacitors, we propose a novel strategy for modification that utilizes electrophoretic deposition (EPD) to deposit Super P onto the surface, thus enhancing its conductivity. After being deposited for 10 min at 80 V, the modified ACFC exhibited higher conductivity. When matched with Si@C anode, the assembled LIC demonstrates excellent initial specific areal capacitance (710 mF cm−2) and cycling retention, with 76.92% remaining after 100 cycles at a current density of 7 mA cm−2. When matched with Si@C anode, the assembled LIC demonstrates excellent initial specific areal capacitance (26.91 F g−1) and cycling retention, with 85.21% remaining after 100 cycles at a current density of 0.2 A g−1. This work showcases the potential of EPD technology in the realm of electrode preparation and offers insights for electrode manufacture in other systems.

Morphology-controlled mesoporous core–shell carbon nanospheres decorated with Cu nanoparticles as highly efficient and reusable catalyst

Environmental pollution caused by industrial waste has recently become a serious issue. Therefore, effective pollutant removal using nanotechnology is required, in which catalysts based on precious metals, such as Pt, Ag, Au, and Pd, are widely utilized. However, the manufacturing costs of precious metal catalysts are high. In this study, copper, a promising metal for catalysis, is evaluated as an alternative to precious metal catalysts because of its low cost, high efficiency, and abundant natural reserves. However, nanoparticle agglomeration is problematic when evaluating the catalytic performance of isolated metal nanoparticles. To solve this problem and maintain a high catalytic activity of Cu, in this study, Cu was loaded on a mesoporous carbon support derived from a carbon precursor with a core–shell structure. The core–shell-structured carbon precursor was obtained by coating resorcinol-formaldehyde polymer spheres as the core with a 50 nm thick polydopamine shell with 10 nm mesopores through π–π stacking interactions. A copper precursor was used to form Cu(OH)2 on the surface of the support, and then the nanocomposite was synthesized at 500 °C for 2 h. The synthesized copper-carbon nanocomposite exhibits high catalytic activity owing to its high specific surface area, porosity, and accessible internal space. It exhibits excellent catalytic activity and stability, along with excellent reusability, in the reduction of 4-nitrophenol to 4-aminophenol using NaBH4. Moreover, excellent catalytic activity, exceeding 99 %, was achieved in the reduction of another organic dye, methylene blue.

The synergistic enhancement or inhibition of different molecular weight components of mannoproteins after ultrafiltration on the encapsulation.

This study investigated the effects of molecular weight regulation on mannoproteins (MPs) in encapsulating both monomeric and oligomeric proanthocyanidins (MOPC). To achieve this, two different conformations of MPs were fractionated by ultrafiltration into two main molecular weight components. The results indicated that regulating molecular weight through ultrafiltration altered the conformation of MPs chains, which in turn affected the intermolecular forces with MOPC. Specifically, the interactions among the different molecular weight components of MPs formed a cross-linking network. High molecular weight components provided external support to this network, while low molecular weight components contributed to internal stabilization. The dense, flexible, and irregular coil structure of MPs facilitated the entry of MOPC into the internal spaces of the cross-linking network. Additionally, protein unfolding into a more stable β-sheet structure further stabilized MPs' cross-linking network, enhancing its capacity to encapsulate MOPC. The presence of more hydrophobic regions and positive charges within the proteins increased the number of binding sites for MOPC. This study aimed to identify the primary structural forms of MPs with potent initial bitter inhibition capabilities on MOPC, and a proposed ultrafiltration method was introduced to modify the triple helix structure of polysaccharide, offering a foundational theoretical framework for enhancing the functional attributes of current or prospective MPs. Additionally, the mixed regulation of polysaccharides with varying conformations was also beneficial for guiding the production of high-efficiency polysaccharide products.