Physical Configuration Research Articles

Sensitivity of precipitation and atmospheric low-level circulation patterns to domain size and choice of parameterization schemes in RegCM4.4 over Central America

The sensitivity of regional climate model simulations to domain size and position is becoming increasingly important for generating reliable climate scenarios. In this study, the Central America CORDEX domain (CCA) at 50 km horizontal resolution with a relaxation zone of 10° around the boundaries (CCA+) was taken as the basis to increase domain size in the RegCM4.4 model. The low-level circulation and precipitation patterns over Central America, the western Caribbean Sea, and the eastern tropical Pacific do not show strong sensitivity to domain size changes for an area increment of 18, 32, and 52% with respect to the size of CCA+. The physical configuration in RegCM4.4 has a greater impact on the representation of relevant climate characteristics and atmospheric processes. Simulated 925 hPa winds over the Caribbean low-level jet (CLLJ) region show unrealistic winter and summer intensities, especially in July. Similar issues were found in other studies for the CCA domain, using different models and physical configurations. A reduction of the critical Richardson number in the selected planetary boundary layer scheme resulted in little change in the strength of the summer component of the CLLJ. The model simulations do not completely capture key regional precipitation patterns such as the mid-summer drought, due to limitations in adequately representing low-level circulation. However, simulations using the Grell cumulus parameterization perform relatively better than those using a mixed scheme (Grell over land-Emanuel over ocean).

A Numerical Modelling Method of Fractured Reservoirs with Embedded Meshes and Topological Fracture Projection Configurations

Projection-based embedded discrete fracture model (pEDFM) is an effective numerical model to handle the flow in fractured reservoirs, with high efficiency and strong generalization of flow models. However, this paper points out that pEDFM fails to handle flow barriers in most cases, and identifies the physical projection configuration of fractures is a key step in pEDFM. This paper presents and proves the equivalence theorem, which explains the geometric nature of physical projection configurations of fractures, that is, the projection configuration of a fracture being physical is equivalent to it being topologically homeomorphic to the fracture, by analyzing the essence of pEDFM. Physical projection configurations of fractures may be rigorously established based on this theorem, allowing pEDFM to obtain physical numerical results for many flow models, particularly those with flow barriers. Furthermore, a natural idea emerges of employing flow barriers to flexibly ‘cut’ the formation to quickly handle the flow problems in the formation with complex geological conditions, and several numerical examples are implemented to test this idea and application of the improved pEDFM.

A study of the relationship between contemporary memorial landscape and user perception

Contemporary Memorial landscape (CML) integrated within the city and people’s life is rapidly growing. It is a landscaped space commemorating individuals or events of the past and keeping them in the memory of people, through physical representation in public areas, by being active rather than passive spaces. Users experience these memorials through engagement with different perceptions, as a result of senses experienced at that space. Placing CML in everyday life and allowing users to engage strengthen their memory and place attachment. This research carries an analysis of CML classification, urban physical configuration, and user sensual experience. The research is carried through literature review and analytical studies for three examples; 9/11, Diana’s, and Jewish memorial. This research highlights the difference between monuments, memorials, and CML. The research concludes a theoretical framework, based on user’s interpretation highlighting their sensual perception, helping the designers bridge their ideas to the user, leading to memorial success.

Extractive Fermentation Processes: Modes of Operation and Application

AbstractBioprocesses can be hampered by product concentrations within a fermentation leading to product‐inhibition, and reductions in yield and productivity. This limitation impacts operational considerations, process economics, and viability, and, ultimately, whether a technology is industrially viable. One approach to circumventing these concerns is in situ extraction of products. In this way, the organism is no longer exposed to the inhibitory product, and fermentation can proceed, often at improved rates. Significant advances in this field have been made in recent years, however, they are for the most part siloed into sub‐fields (focusing on the product extracted, or the method of extraction). This review considers in situ extraction more holistically in terms of i) the separation methodology, ii) the mode of reactor operation, and iii) the physical reactor configuration. The summary hopes to give insight into promising areas for research and potentially spark ideas for novel in situ extractive processes.

Sparse Array Design for DOA Estimation of Non-Circular Signals: Reduced Co-Array Redundancy and Increased DOF

In the past decade, sparse arrays have aroused considerable attention for the ability to provide larger array aperture, more degrees of freedom (DOFs) and better estimation performance compared with the uniform linear array (ULA). In this paper, the problem of sparse array design is investigated for direction of arrival (DOA) estimation of non-circular (NC) signals, where both the difference co-array (DCA) and sum co-array (SCA) of physical array configuration can be utilized. Specifically, we first introduce a sliding array strategy which moves the array along the axis as a whole in order to reduce the co-array redundancy and enhance the consecutive DOFs of the sum-difference co-array (SDCA). Subsequently, we focus on the SCA of the conventional nested array (NA) and propose an approach which increases the DOFs of the SCA by relocating proper sensors. Furthermore, based on the above strategy and approach, we derive an extended sliding nested array (ESNA) with few redundant virtual sensors and an enhanced SCA, which can offer increased consecutive DOFs, enlarged virtual array aperture (VAA) and can thus bring high angle estimation accuracy of NC signals. Finally, analytic solutions and simulation results are given to validate the superiority of the proposed ESNA in terms of DOFs and estimation performance.

Multi-Scenario Physical Energy Storage Planning of Integrated Energy Systems Considering Dynamic Characteristics of Heating Network and Demand Response

The configuration of energy storage in the integrated energy system (IES) can effectively improve the consumption rate of renewable energy and the flexibility of system operation. Due to the high cost and long cycle of the physical energy storage construction, the configuration of energy storage is limited. The dynamic characteristics of the heating network and the demand-side response (DR) can realize the space-time transfer of energy. Although there is no actual energy storage equipment construction, it plays a similar role to physical energy storage and can be considered as virtual energy storage in IES planning. In this paper, a multi-scenario physical energy storage planning model of IES considering the dynamic characteristics of the heating network and DR is proposed. To make full use of the energy storage potential of the proposed model, the virtual energy storage features of the dynamic heating characteristics of the heating network and DR are analyzed at first. Next, aiming at the uncertainty of wind turbine (WT) and photovoltaic (PV) output, the scenario analysis method is used to describe the wind and photovoltaic power output with different probabilities. Finally, an electrothermal IES with an IEEE 33-node network and a 26-node heating network serves as an example to verify the effectiveness of the proposed model. The case study shows that the proposed model effectively reduces the physical energy storage configuration and achieves the economic trade-off between the investment cost and the operation cost.

The Uncertainty Quantification for Parameters Optimization in SERF Atomic Magnetomer

The magnetometer is a multi-parameter system, parameters optimization is always the problem to improve the sensitivity of the atomic magnetometer. Multiple parameters hardly decide the optimized conditions in the experiments because of the influence of several parameters and parameters may interact with each other. Besides, the influence of parameters on the signal-to-noise ratio can hardly be analyzed theoretically due to the complex physical configuration. We used a generalized polynomial chaos expansion to construct an agent model for the SERF atomic magnetometer to replace its complex physical model, and used a variance-based sobol method to perform a global sensitivity analysis of the parameters in this paper. The mathematical method of uncertainty quantification is used to comprehensively analyze six parameters’ effect on SERF atomic magnetometer performance. The results show that the probe laser power has the greatest impact on the atomic magnetometer, and it is the parameter with the highest degree of linearity with the atomic magnetometer. In accordance with the results of the uncertainty quantification analysis, the parameters of the probe laser power of the SERF atomic magnetometer were experimentally optimized, and the performance of the magnetometer was significantly improved.

CFD based study of fluid flow and heat transfer effect for novel turning tool configured with internal cooling channel

Internal-cooling method due to its numerous advantages has been used during the machining of hard to cut and difficult to machine materials. Cooling channels developed in the cutting inserts, drills, end mills and grinding wheels are used for the heat removal which is concentrated at a smaller region during machining process. So, these cooling channels play a vital role in decreasing the temperature and wear rate of the tools. The heat generation and transfer rate depend upon the physical configuration of the cooling channel. This research work presents novelty in the concept of developing internal cooling channel cutting inserts with different profiles. Three different profiles have been developed to investigate cooling effect on the turning tool insert with different shapes. The results have been compared with the standard tool having no cooling channel. Computational Fluid Dynamics (CFD) has been used to simulate temperature rise for all profiles. A temperature drop of 188 K has been found for internally cooled cutting insert in comparison to the standard tool having no channel. It has also been found that the temperature difference of range 20 K–88 K can be achieved by varying the profile of the channel. Besides this, an increase in the inlet pressure of the cutting fluid has been found to make the coolant profile more efficient in terms of heat removal. Through the velocity vector results, it has been found that with more flow velocity of coolant inside the channel more heat transfer takes place. Turbulence Kinetic Energy (TKE) results showed that the heat transfer rate can be increased with an increase in the TKE value which in turn depends upon the profile of the coolant flow channel. This CFD study in turn has laid the platform for setting the optimum parameters during the turning of Titanium alloy with internal cooling channels.

When perception is stronger than physics: Perceptual similarities rather than laws of physics govern the perception of interacting objects

When several multistable displays are viewed simultaneously, their perception is synchronized, as they tend to be in the same perceptual state. Here, we investigated the possibility that perception may reflect embedded statistical knowledge of physical interaction between objects for specific combinations of displays and layouts. We used a novel display with two ambiguously rotating gears and an ambiguous walker-on-a-ball display. Both stimuli produce a physically congruent perception when an interaction is possible (i.e., gears counterrotate, and the ball rolls under the walker’s feet). Next, we gradually manipulated the stimuli to either introduce abrupt changes to the potential physical interaction between objects or keep it constant despite changes in the visual stimulus. We characterized the data using four different models that assumed (1) independence of perception of the stimulus, (2) dependence on the stimulus’s properties, (3) dependence on physical configuration alone, and (4) an interaction between stimulus properties and a physical configuration. We observed that for the ambiguous gears, the perception was correlated with the stimulus changes rather than with the possibility of physical interaction. The perception of walker-on-a-ball was independent of the stimulus but depended instead on whether participants responded about a relative motion of two objects (perception was biased towards physically congruent motion) or the absolute motion of the walker alone (perception was independent of the rotation of the ball). None of the two experiments supported the idea of embedded knowledge of physical interaction.

A Hybrid particle swarm optimization of the rational function model for satellite strip images ortho-rectification

ABSTRACT The rational function model (RFM) is widely used for high-resolution satellite imagery allowing its use in GIS and remote sensing applications. RFM can be seen as a non-parametric model that establishes a geometric transformation between image and ground coordinate spaces. Unlike the rigorous models, it constitutes an easy and simple approach where any prior knowledge about the sensor’s physical configuration and parameters is required. For a precise ortho-rectification, RFM requires a large number of accurate and well-distributed ground control points (GCPs) which is a time-consuming and expensive process. Moreover, adjustment errors may occur due to the over-parameterization resulting from the high number of coefficients in this model. In fact, coefficients in RFM do not have any physical meaning, which makes it impossible to find their best combination. In order to overcome this problem, optimization based on evolutionary algorithms seems to be an appropriate solution. In this paper, a hybrid binary of particle swarm optimization (PSO) method is proposed. It combines the PSO concept with that of genetic algorithms by adding two new operations in the binary version of PSO consisting of crossover and mutation in order to increase the convergence speed and avoid the local optimum phenomenon. The proposed algorithm has been applied on two data sets provided by the Alsat-2 Algerian satellite in different configurations, namely standard scenes and strips which are a group of scenes acquired continuously from the same orbit. To the best of our knowledge, this is the first work dealing with the use of PSO for the RFM optimization aiming at the geometrical modelling of a strip of images. The obtained results have shown that the proposed HPSO-RFM method outperforms other competing methods by achieving, for the best scenario, an accuracy improvement of about 38% and 21% over PSORFO and PSO-KFCV, respectively.

Measurement of low sap flux density in plants using the single needle heat pulse probe

Heat pulse probes are used worldwide to quantify sap flow in plants. Probes consisting of a single needle inserted into a plant have a simple physical configuration relative to multi-probe methods. The single probe also minimizes physical damage to plant tissue. Single probe methods are therefore increasingly used for sap flux density measurements. However, at low sap flux density values, existing single probe heat pulse (SPHP) methods cannot be used for accurate measurements. To increase the sensitivity of SPHP to low sap flux densities, this paper describes and validates a simplified expression of sap flow and heat transport under various heat inputs and finite heat pulse time intervals. To test this theoretical development, measurements were collected from SPHP probes inserted into mature poplar forest trees (Populus tomentosa Carrière) during the 2020 growing season. The results show that the new method can successfully monitor low sap flux density: the lowest measured heat pulse velocity was 3 cm h−1, which is an improvement from the original SPHP method (20 cm h−1). The improved SPHP method had a root mean square deviation (RMSD) of 1.63 cm h−1 in comparison with the heat ratio (HR) method. The proposed SPHP method is therefore suitable for quantifying both low and high sap flux densities.

Investigating the Urban Spatial Growth by Using Space Syntax and GIS—A Case Study of Famagusta City

Urban morphology studies generally study how a city grows and transforms to embody its embedded history. This study examines the potentials of using space syntax and GIS methods to study the morphological evolution of traditional city centers throughout the historical periods. Using space syntax properties, human activities and movement patterns in the city can be investigated, typically by considering the degree to which urban spaces are integrated and connected. Through the syntactic analysis of street networks, urban planners can derive a better comprehending of the evolution of urban growth, and gain new insights to help with the new urban development. Space syntax theory and tools can extend the modeling capabilities of GIS, particularly in terms of the development of new advances and experimentation in the analysis of street network systems. Indeed, this study brings academic rigor and attention to details in the spatial growth and morphological evolution in the case of Famagusta city. The finding of this study will redound to the advantage of society considering that socio-economic processes and physical configuration play a significant role in the evolution of a city.

Emotional Responses to the Visual Patterns of Urban Streets: Evidence from Physiological and Subjective Indicators.

Despite recent progress in the research of people’s emotional response to the environment, the built—rather than natural—environment’s emotional effects have not yet been thoroughly examined. In response to this knowledge gap, we recruited 26 participants and scrutinized their emotional response to various urban street scenes through an immersive exposure experiment using virtual reality. We utilized new physiological monitoring technologies that enable synchronized observation of the participants’ electroencephalography, electrodermal activity, and heart rate, as well as their subjective indicators. With the newly introduced measurement for the global visual patterns of the built environment, we built statistical models to examine people’s emotional response to the physical element configuration and color composition of street scenes. We found that more diverse and less fragmented scenes inspired positive emotional feelings. We also found (in)consistency among the physiological and subjective indicators, indicating a potentially interesting neural−physiological interpretation for the classic form−function dichotomy in architecture. Besides the practical implications on promoting physical environment design, this study combined objective physiology-monitoring technology and questionnaire-based research techniques to demonstrate a better approach to quantify environment−emotion relationships.

감염병 대응 임시음압격리병동의 디자인 요구사항 도출 및 콘셉트 시나리오 탐색

Background Recently, the demand for isolation rooms has rapidly increased with the spread of infectious diseases such as COVID-19. Previous studies investigated temporary isolation wards to resolve the shortage of beds. Most of the studies, however, focused on construction methods and the capability of equipment instead of experiential aspects such as medical activities and life in quarantine. This article presents design requirements and the associated example design cases based on the identified needs of medical and facility staff from a participatory design workshop. Methods A participatory design workshop was conducted with 21 medical and facility staff in a hospital specializing in infectious diseases. Two workshop sessions including MACRO-level design for overall configurations and MICRO-level design for room layouts were conducted to participants. The collected data was analyzed to derive design requirements for temporary isolation wards. To verify the relevance and applicability of the derived design requirements, we asked four designers to develop conceptual designs of new isolation wards based on the card-type design aid, which includes the details of the requirements. Results From the design workshop, five design requirements were derived: supporting the communication between the inside and outside of an isolation ward;preventing contact with the infection source;relieving emotional anxiety;relieving medical staffs’ work burden;and securing an appropriate hospital environment. During the conceptual design process using the design aids, designers created animated conceptual scenarios for isolation wards (information system using QR codes, serving robots for delivery, trash bin discharging wastes in safety, digital window, and plugin facility module). Conclusions The design requirements can be applied for new medical service design projects, which should consider experiential aspects in addition to the physical and spatial aspects in context of temporary isolation ward design. The example scenarios would be beneficial for further exploration of a new product, system, and service design for infectious diseases while considering the experiences beyond the physical configuration. © 2021. This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License org/licenses/bync/ 3.0/), which permits unrestricted educational provided the original work is properly cited. All Rights Reserved.

Dynamic Performance Characterization Techniques in Gallium Nitride-Based Electronic Devices

In this paper, we compare and discuss the main techniques for the analysis of the dynamic performance of GaN-based transistors. The pulsed current-voltage characterization provides information on the effect of different trapping voltages on various bias points of the device under test, leading to the detection of all the possible effects, as well as to the choice of the optimal filling and measure bias conditions in other techniques. The drain current transients use one of the identified bias configurations to extract information on the deep level signature responsible for the performance variation and, thus, they can pinpoint the corresponding physical crystal lattice configuration, providing useful information to the growers on how the issue can be solved. Finally, given the complex interplay between the filling and emission time constants, the gate frequency sweeps can be used to obtain the real performance in the target operating condition.

Telepresence Robots in the Classroom

This study used the concept of shared affordance space to explore students’ perceptions of the use of a telepresence robot in a face-to-face classroom. Results from this qualitative pilot study suggest the telepresence robot has the potential to provide enough autonomy and agency for both the remote user and the in-class students to perceive a shared affordance space. Robot users and classmates use human pronouns to describe the robot user and discuss a process of adjusting to its presence. The physical configuration of the classroom can either facilitate or hinder this process. The research provides greater understanding of the experiences of students in a face-to-face classroom that includes remote students attending class using a telepresence robot. It can help educators design and implement these experiences in a way that creates a beneficial classroom experience for both in-class and remote learners.

Study of power flow mechanism of capacitive power transfer system based on Poynting vector analysis

In this paper, the power flow mechanism of a typical Capacitive Power Transfer (CPT) system is studied by analysing the electric field, magnetic field, and Poynting vector, to determine the power distribution as well as the average power flow to the load. It is found that the average power from the source flows along the wires on the transmitting side and passes the external areas of the coupling plates mainly along the channel between the two coupling pairs (instead of going through the air gaps in between), then converges along the wires before reaching the load. The average power calculated by integrating the real part of the Poynting vector across a defined power flow plane at the receiving end is consistent with CST (Computer Simulation Technology) simulation, circuit analysis, and practical measurements of the CPT system. Although the power density described by Poynting vector changes with the separation distance between the two coupling pairs, the total average power keeps approximately constant because the power flow area changes accordingly. Compared to the traditional lumped circuit analysis, the Poynting vector analysis shows the power distribution around the coupling plates in relation to their physical configuration. This research reveals the power flow mechanism and distribution in a CPT system from field point of view, which is useful to gain deeper understanding of the CPT system beyond the traditional circuit theory and would also be helpful to improve practical system design in the future.

Socio-technical practices of young children and parents in the home: a case study from Japan

ABSTRACT The purpose of this study is to explore what socio-technical arrangements are created from an amalgamation of young children, their families, and technology. Lawrence Lessig’s four forces – law, social norms, market, and architecture – were used to analyze the practices and constraints of children’s digital activities and parental involvement in the home. A home-visit interview study with six parent–child pairs found the children’s activities to be constrained by four elements: 1) rules arranged by children and parents; 2) domestic norms among their families; 3) markets through which parents purchase digital devices; and 4) architecture in the physical and spatial configuration of the home. These four constraints created new opportunities for children’s activities. The children’s use of technology not only expanded their activities, but also exploited technological vulnerabilities. The ambiguity of the activity led to a reorganization of the domestic architecture and a reconstruction of the rules between parents and children. IMPACT SUMMARY a. Prior State of Knowledge: Children’s domestic digital activities are collectively composed of heterogeneous actors including children, parents, artifacts, and technology. It is useful to introduce a perspective of human and non-human relationships and analyze what kinds of socio-technical arrangements exist in their activities. b. Novel Contributions: An analysis of children’s digital activities in the home, using Lessig’s four forces, showed both expansion and vulnerability of their activities. This ambiguity led to a reconstruction of the domestic architecture and the rules between parents and children. c. Practical Implications: Lessig’s four elements broaden children’s digital activities beyond individual children to parent-child relationships and socio-technical arrangements. Parents and practitioners can use them to consider extensions and constraints of children’s activities with technology.

Dendrite-Suppressing Polymer Materials for Safe Rechargeable Metal Battery Applications: From the Electro-Chemo-Mechanical Viewpoint of Macromolecular Design.

Metal batteries have been emerging as next-generation battery systems by virtue of ultrahigh theoretical specific capacities and low reduction potentials of metallic anodes. However, significant concerns regarding the uncontrolled metallic dendrite growth accompanied by safety hazards and short lifespan have impeded practical applications of metal batteries. Although a great deal of effort has been pursued to highlight the thermodynamic origin of dendrite growth and a variety of experimental methodologies for dendrite suppression, the roles of polymer materials in suppressing the dendrite growth have been underestimated. This review aims to give a state-of-the-art overview of contemporary dendrite-suppressing polymer materials from the electro-chemo-mechanical viewpoint of macromolecular design, including i) homogeneous distribution of metal ion flux, ii) mechanical blocking of metal dendrites, iii) tailoring polymer structures, and iv) modulating the physical configuration of polymer membranes. Judiciously tailoring electro-chemo-mechanical properties of polymer materials provides virtually unlimited opportunities to afford safe and high-performance metal battery systems by resolving problematic dendrite issues. Transforming these rational design strategies into building dendrite-suppressing polymer materials and exploiting them towards polymer electrolytes, separators, and coating materials hold the key to realizing safe, dendrite-free, and long-lasting metal battery systems.

Coastal complexity of the Antarctic continent

Abstract. The Antarctic outer coastal margin (i.e. the coastline itself or the terminus or front of ice shelves, whichever is adjacent to the ocean) is a key interface between the ice sheet and terrestrial environments and the Southern Ocean. Its physical configuration (including both length scale of variation, orientation, and aspect) has direct bearing on several closely associated cryospheric, biological, oceanographical, and ecological processes, yet no study has quantified the coastal complexity or orientation of Antarctica's coastal margin. This first-of-a-kind characterization of Antarctic coastal complexity aims to address this knowledge gap. We quantify and investigate the physical configuration and complexity of Antarctica's circumpolar outer coastal margin using a novel technique based on ∼ 40 000 random points selected along a vector coastline derived from the MODIS Mosaic of Antarctica dataset. At each point, a complexity metric is calculated at length scales from 1 to 256 km, giving a multiscale estimate of the magnitude and direction of undulation or complexity at each point location along the entire coastline. Using a cluster analysis to determine characteristic complexity “signatures” for random nodes, the coastline is found to comprise three basic groups or classes: (i) low complexity at all scales, (ii) most complexity at shorter scales, and (iii) most complexity at longer scales. These classes are somewhat heterogeneously distributed throughout the continent. We also consider bays and peninsulas separately and characterize their multiscale orientation. This unique dataset and its summary analysis have numerous applications for both geophysical and biological studies. All these data are referenced by https://doi.org/10.26179/5d1af0ba45c03 (Porter-Smith et al., 2019) and are available free of charge at http://data.antarctica.gov.au (last access: 7 June 2021).