Search results for: spatial circuit
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 3165

Search results for: spatial circuit

2745 Improving the LDMOS Temperature Compensation Bias Circuit to Optimize Back-Off

Authors: Antonis Constantinides, Christos Yiallouras, Christakis Damianou

Abstract:

The application of today's semiconductor transistors in high power UHF DVB-T linear amplifiers has evolved significantly by utilizing LDMOS technology. This fact provides engineers with the option to design a single transistor signal amplifier which enables output power and linearity that was unobtainable previously using bipolar junction transistors or later type first generation MOSFETS. The quiescent current stability in terms of thermal variations of the LDMOS guarantees a robust operation in any topology of DVB-T signal amplifiers. Otherwise, progressively uncontrolled heat dissipation enhancement on the LDMOS case can degrade the amplifier’s crucial parameters in regards to the gain, linearity, and RF stability, resulting in dysfunctional operation or a total destruction of the unit. This paper presents one more sophisticated approach from the traditional biasing circuits used so far in LDMOS DVB-T amplifiers. It utilizes a microprocessor control technology, providing stability in topologies where IDQ must be perfectly accurate.

Keywords: LDMOS, amplifier, back-off, bias circuit

Procedia PDF Downloads 339
2744 From Social Equity to Spatial Equity in Urban Space: Precedent Study Approach

Authors: Dorsa Pourmojib, Marc J. Boutin

Abstract:

Urban space is used everyday by a diverse range of urban dwellers, each with different expectations. In this space, opportunities and resources are not distributed equitably among urban dwellers, despite the importance of inclusivity. In addition, some marginalized groups may not be considered. These include people with low incomes, immigrants from diverse cultures, various age groups, and those with special needs. To this end, this research aims to enhance social equity in urban space by bridging the gap between social equity and spatial equity in the urban context. This gap in the knowledge base related to urban design may be present for several reasons; lack of studies on relationship between social equity and spatial equity in urban open space, lack of practical design strategies for promoting social equity in urban open space, lack of proper site analysis in terms of context and users of the site both for designing new urban open spaces and developing the existing ones, and lack of researchers that are designers and finally it could be related to priorities of the city’s policies in addressing such issues, since it is time, money and energy consuming. The main objective of this project is addressing the aforementioned gap in the knowledge by exploring the relationship between social equity and spatial equity in urban open space. Answering the main question of this research is a promising step to this end; 'What are the considerations towards providing social equity through the design of urban elements that offer spatial equity?' To answer the main question of this research there are several secondary questions which should be addressed. Such as; how can the characteristics of social equity be translated to spatial equity? What are the diverse user’s needs and which of their needs are not considered in that site? What are the specific elements in the site which should be designed in order to promote social equity? What is the current situation of social and spatial equity in the proposed site? To answer the research questions and achieve the proposed objectives, a three-step methodology has been implemented. Firstly, a comprehensive research framework based on the available literature has been presented. Afterwards, three different urban spaces have been analyzed in terms of specific key research questions as the precedent studies; Naqsh-e Jahan Square (Iran), Superkilen Park (Denmark) and Campo Dei Fiori (Italy). In this regard, a proper gap analysis of the current situation and the proposed situation of these sites has been conducted. Finally, by combining the extracted design considerations from the precedent studies and the literature review, practical design strategies have been introduced as a result of this research. The presented guidelines enable the designers to create socially equitable urban spaces. To conclude, this research proposes a spatial approach to social inclusion and equity in urban space by presenting a practical framework and criteria for translating social equity to spatial equity in urban areas.

Keywords: inclusive urban design, social equity, social inclusion, spatial equity

Procedia PDF Downloads 142
2743 Induction Motor Stator Fault Analysis Using Phase-Angle and Magnitude of the Line Currents Spectra

Authors: Ahmed Hamida Boudinar, Noureddine Benouzza, Azeddine Bendiabdellah, Mohamed El Amine Khodja

Abstract:

This paper describes a new diagnosis approach for identification of the progressive stator winding inter-turn short-circuit fault in induction motor. This approach is based on a simple monitoring of the combined information related to both magnitude and phase-angle obtained from the fundamental by the three line currents frequency analysis. In addition, to simplify the interpretation and analysis of the data; a new graphical tool based on a triangular representation is suggested. This representation, depending on its size, enables to visualize in a simple and clear manner, the existence of the stator inter-turn short-circuit fault and its discrimination with respect to a healthy stator. Experimental results show well the benefit and effectiveness of the proposed approach.

Keywords: induction motor, magnitude, phase-angle, spectral analysis, stator fault

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2742 Spatio-temporal Distribution of the Groundwater Quality in the El Milia Plain, Kebir Rhumel Basin, Algeria

Authors: Lazhar Belkhiri, Ammar Tiri, Lotfi Mouni

Abstract:

In this research, we analyzed the groundwater quality index in the El Milia plain, Kebir Rhumel Basin, Algeria. Thirty-three groundwater samples were collected from wells in the El Milia plain during April 2015. In this study, pH and electrical conductivity (EC) were conducted at each sampling well. Eight hydrochemical parameters such as calcium (Ca), magnesium (Mg), sodium (Na), potassium (K), chlorid (Cl), sulfate (SO4), bicarbonate (HCO3), and Nnitrate (NO3) were analysed. The entropy water quality index (EWQI) method was employed to evaluate the groundwater quality in the study area. Moran’s I and the ordinary kriging (OK) interpolation technique were used to examine the spatial distribution pattern of the hydrochemical parameters in the groundwater. It was found that the hydrochemical parameters Ca, Cl, and HCO3 showed strong spatial autocorrelation in the El Milia plain, indicating a spatial dependence and clustering of these parameters in the groundwater. The groundwater quality was evaluated using the entropy water quality index (EWQI). The results showed that approximately 86% of the total groundwater samples in the study area fall within the moderate groundwater quality category. The spatial map of the EWQI values indicated an increasing trend from the south-west to the northeast, following the direction of groundwater flow. The highest EWQI values were observed near El Milia city in the center of the plain. This spatial pattern suggests variations in groundwater quality across the study area, with potentially higher risks near the city center. Therefore, the results obtained in this research provide very useful information to decision-makers.

Keywords: entropy water quality index (EWQI), moran’s i, ordinary kriging interpolation, el milia plain

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2741 Permanent Magnet Synchronous Generator: Unsymmetrical Point Operation

Authors: P. Pistelok

Abstract:

The article presents the concept of an electromagnetic circuit generator with permanent magnets mounted on the surface rotor core designed for single phase work. Computation field-circuit model was shown. The spectrum of time course of voltages in the idle work was presented. The cross section with graphically presentation of magnetic induction in particular parts of electromagnetic circuits was presented. Distribution of magnetic induction at the rated load point for each phase were shown. The time course of voltages and currents for each phases for rated power were displayed. An analysis of laboratory results and measurement of load characteristics of the generator was discussed. The work deals with three electromagnetic circuits of generators with permanent magnet where output voltage characteristics versus rated power were expressed.

Keywords: permanent magnet generator, permanent magnets, vibration, course of torque, single phase work, asymmetrical three phase work

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2740 Spatiotemporal Analysis of Visual Evoked Responses Using Dense EEG

Authors: Rima Hleiss, Elie Bitar, Mahmoud Hassan, Mohamad Khalil

Abstract:

A comprehensive study of object recognition in the human brain requires combining both spatial and temporal analysis of brain activity. Here, we are mainly interested in three issues: the time perception of visual objects, the ability of discrimination between two particular categories (objects vs. animals), and the possibility to identify a particular spatial representation of visual objects. Our experiment consisted of acquiring dense electroencephalographic (EEG) signals during a picture-naming task comprising a set of objects and animals’ images. These EEG responses were recorded from nine participants. In order to determine the time perception of the presented visual stimulus, we analyzed the Event Related Potentials (ERPs) derived from the recorded EEG signals. The analysis of these signals showed that the brain perceives animals and objects with different time instants. Concerning the discrimination of the two categories, the support vector machine (SVM) was applied on the instantaneous EEG (excellent temporal resolution: on the order of millisecond) to categorize the visual stimuli into two different classes. The spatial differences between the evoked responses of the two categories were also investigated. The results showed a variation of the neural activity with the properties of the visual input. Results showed also the existence of a spatial pattern of electrodes over particular regions of the scalp in correspondence to their responses to the visual inputs.

Keywords: brain activity, categorization, dense EEG, evoked responses, spatio-temporal analysis, SVM, time perception

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2739 Aesthetic Embodiment of the Visual and/or Non-Visual: the Becoming of a Spatial Installation Exhibition Influenced by Shamanic Healing

Authors: Ningfei Xiao, Simon Twose, Hannah Hopewell

Abstract:

In urban settings worldwide, artists and researchers have drawn from shamanic healing, providing insightful responses to the environment. This project is a transdisciplinary creative research project where architecture and art practice draw from shamanic healing and provide the potential to expand knowledge of public space and inspire more aesthetic explorations of public spatial visions. The research started from the encounters with the Ewengki/Evenki shaman tribe in settlement areas of northern China in 2019 and extended through the partnerships with Maori artists in Poneke Aotearoa, New Zealand, in 2023. Based on the learnings and collaborations with female indigenous tradition practitioners and the healing that the researcher received from the land, a spatial installation exhibition was developed in this project. Indigenous practices are intricately woven with contemporary technology, merging visuals, soundscapes, and other non-visual aesthetics influenced by the researcher's personal experiences of embodied shamanic healing with brainwave generative technology. This synthesis seeks to ritualize and reimagine future public spaces, encompassing streetscapes and greenscapes from China to Aotearoa, and fostering connections between urbanized human body, mind, spirit, and land. In doing so, the project presents a feminist posthuman inquiry into how individuals perceive materiality within the context of a future city. Grounded in creative research and embodied methodologies, this paper focuses on the conceptual and autoethnographic aspects of visual-non-visual aesthetics and their creative representation. Through the exploration of aesthetics beyond the visual realm within urban and spatial contexts, this project showcases the spatial installation exhibition as an example of shamanic influence and related response to public space through embodied artistry and transdisciplinary creative inquiry.

Keywords: aesthetic, embodiment, visual and/or non-visual, spatial installation, shamanic healing, public space

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2738 Continuous Measurement of Spatial Exposure Based on Visual Perception in Three-Dimensional Space

Authors: Nanjiang Chen

Abstract:

In the backdrop of expanding urban landscapes, accurately assessing spatial openness is critical. Traditional visibility analysis methods grapple with discretization errors and inefficiencies, creating a gap in truly capturing the human experi-ence of space. Addressing these gaps, this paper introduces a distinct continuous visibility algorithm, a leap in measuring urban spaces from a human-centric per-spective. This study presents a methodological breakthrough by applying this algorithm to urban visibility analysis. Unlike conventional approaches, this tech-nique allows for a continuous range of visibility assessment, closely mirroring hu-man visual perception. By eliminating the need for predefined subdivisions in ray casting, it offers a more accurate and efficient tool for urban planners and architects. The proposed algorithm not only reduces computational errors but also demonstrates faster processing capabilities, validated through a case study in Bei-jing's urban setting. Its key distinction lies in its potential to benefit a broad spec-trum of stakeholders, ranging from urban developers to public policymakers, aid-ing in the creation of urban spaces that prioritize visual openness and quality of life. This advancement in urban analysis methods could lead to more inclusive, comfortable, and well-integrated urban environments, enhancing the spatial experience for communities worldwide.

Keywords: visual openness, spatial continuity, ray-tracing algorithms, urban computation

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2737 Effect of Jet Diameter on Surface Quenching at Different Spatial Locations

Authors: C. Agrawal, R. Kumar, A. Gupta, B. Chatterjee

Abstract:

An experimental investigation has been carried out to study the cooling of a hot horizontal Stainless Steel surface of 3 mm thickness, which has 800±10 °C initial temperature. A round water jet of 22 ± 1 °C temperature was injected over the hot surface through straight tube type nozzles of 2.5-4.8 mm diameter and 250 mm length. The experiments were performed for the jet exit to target surface spacing of 4 times of jet diameter and jet Reynolds number of 5000-24000. The effect of change in jet Reynolds number on the surface quenching has been investigated form the stagnation point to 16 mm spatial location.

Keywords: hot-surface, jet impingement, quenching, stagnation point

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2736 The Exploration on the Mode of Renovation and Reconstruction of Old Factory Buildings for Cultural and Creative Industrial Parks

Authors: Yu Pan, Jing Wu, Lingwan Shen

Abstract:

Since the reform and opening, China's cities have developed rapidly, and the industrial structure has been constantly adjusted and optimized. A large number of industrial plants have lost their production functions and become idle buildings. The renovation projects for the old factory buildings are important parts of the urban renewal, and most of them are the cultural and creative industrial park projects. In this paper, a statistical analysis of renovation projects of the representative cultural and creative industrial parks in recent years was conducted. According to the user's spatial experience satisfaction survey, the physical and spatial factors affecting the space regeneration of the old factory were concluded. Thus the relationship between space regeneration and material, structure, internal and external space design has been derived. Finally, we summarized the general spatial processing model in which the contradiction between ‘new’ and ‘old’ can be grafted and transformed.

Keywords: renovation of factory buildings, urban renewal, the cultural and creative industrial park, space regeneration, reconstruction mode

Procedia PDF Downloads 147
2735 A Coupling Study of Public Service Facilities and Land Price Based on Big Data Perspective in Wuxi City

Authors: Sisi Xia, Dezhuan Tao, Junyan Yang, Weiting Xiong

Abstract:

Under the background of Chinese urbanization changing from incremental development to stock development, the completion of urban public service facilities is essential to urban spatial quality. As public services facilities is a huge and complicated system, clarifying the various types of internal rules associated with the land market price is key to optimizing spatial layout. This paper takes Wuxi City as a representative sample location and establishes the digital analysis platform using urban price and several high-precision big data acquisition methods. On this basis, it analyzes the coupling relationship between different public service categories and land price, summarizing the coupling patterns of urban public facilities distribution and urban land price fluctuations. Finally, the internal mechanism within each of the two elements is explored, providing the reference of the optimum layout of urban planning and public service facilities.

Keywords: public service facilities, land price, urban spatial morphology, big data

Procedia PDF Downloads 215
2734 Impact of Map Generalization in Spatial Analysis

Authors: Lin Li, P. G. R. N. I. Pussella

Abstract:

When representing spatial data and their attributes on different types of maps, the scale plays a key role in the process of map generalization. The process is consisted with two main operators such as selection and omission. Once some data were selected, they would undergo of several geometrical changing processes such as elimination, simplification, smoothing, exaggeration, displacement, aggregation and size reduction. As a result of these operations at different levels of data, the geometry of the spatial features such as length, sinuosity, orientation, perimeter and area would be altered. This would be worst in the case of preparation of small scale maps, since the cartographer has not enough space to represent all the features on the map. What the GIS users do is when they wanted to analyze a set of spatial data; they retrieve a data set and does the analysis part without considering very important characteristics such as the scale, the purpose of the map and the degree of generalization. Further, the GIS users use and compare different maps with different degrees of generalization. Sometimes, GIS users are going beyond the scale of the source map using zoom in facility and violate the basic cartographic rule 'it is not suitable to create a larger scale map using a smaller scale map'. In the study, the effect of map generalization for GIS analysis would be discussed as the main objective. It was used three digital maps with different scales such as 1:10000, 1:50000 and 1:250000 which were prepared by the Survey Department of Sri Lanka, the National Mapping Agency of Sri Lanka. It was used common features which were on above three maps and an overlay analysis was done by repeating the data with different combinations. Road data, River data and Land use data sets were used for the study. A simple model, to find the best place for a wild life park, was used to identify the effects. The results show remarkable effects on different degrees of generalization processes. It can see that different locations with different geometries were received as the outputs from this analysis. The study suggests that there should be reasonable methods to overcome this effect. It can be recommended that, as a solution, it would be very reasonable to take all the data sets into a common scale and do the analysis part.

Keywords: generalization, GIS, scales, spatial analysis

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2733 Establishing Taiwan's Marine Space Planning System

Authors: Wen-Yan Chiau

Abstract:

Taiwan passed the 'Basic Ocean Act' in November 2019, and in accordance with Article 4 of its provisions, the government should draft a decree on ocean space planning (MSP). In the past few years, although Taiwan has passed the 'Coastal Zone Management Act' and the 'Spatial Planning Act', in the face of multiple use of marine areas, it still lacks a comprehensive marine area use blueprint and a fundamental mechanism for multi-purpose use planning management. In particular, Taiwan's active development of offshore wind power is facing this problem, and it is impossible to fully reconcile the use of each domain and the public welfare through a holistic system, highlighting the urgency of the establishment of MSP system. Therefore, this article will review relevant Taiwan laws and regulations, refer to important international initiatives and experiences, and participate in the exchange of practical experience in international conference(s), and propose adequate framework, principles, procedures, and promotion strategies on MSP. Possible solutions to promote sustainable and wise use in Taiwan's waters will also be suggested for comments.

Keywords: basic ocean act, coastal zone management act, marine spatial planning, spatial planning act, Taiwan

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2732 Magnetic Simulation of the Underground Electric Cable in the Presence of a Short Circuit and Harmonics

Authors: Ahmed Nour El Islam Ayad, Wafa Krika, Abdelghani Ayad, Moulay Larab, Houari Boudjella, Farid Benhamida

Abstract:

The purpose of this study is to evaluate the magnetic emission of underground electric cable of high voltage, because these power lines generate electromagnetic interaction with other objects near to it. The aim of this work shows a numerical simulation of the magnetic field of buried 400 kV line in three cases: permanent and transient states of short circuit and the last case with the presence of the harmonics at different positions as a function of time variation, with finite element resolution using Comsol Multiphysics software. The results obtained showed that the amplitude and distribution of the magnetic flux density change in the transient state and the presence of harmonics. The results of this work calculate the magnetic field generated by the underground lines in order to evaluate and know their impact on ecology and health.

Keywords: underground, electric power cables, cables crossing, harmonic, emission

Procedia PDF Downloads 229
2731 The Effectiveness of Adaptive Difficulty Adjustment in Touch Tablet App on Young Children's Spatial Problem Solving Development

Authors: Chenchen Liu, Jacques Audran

Abstract:

Using tablet apps with a certain educational purpose to promote young children’s cognitive development, is quite common now. Developing an educational app on an Ipad like tablet, especially for a young child (age 3-5) requires an optimal level of challenge to continuously attract children’s attention and obtain an educational effect. Adaptive difficulty adjustment, which could dynamically set the difficulty in the challenge according to children’s performance, seems to be a good solution. Since space concept plays an important role in young children’s cognitive development, we made an experimental comparison in a French kindergarten between one group of 23 children using an educational app ‘Debout Ludo’ with adaptive difficulty settings and another group of 20 children using the previous version of ‘Debout Ludo’ with a classic incremental difficulty adjustment. The experiment results of spatial problem solving indicated that a significantly higher learning outcome was acquired by the young children who used the adaptive version of the app.

Keywords: adaptive difficulty, spatial problem solving, tactile tablet, young children

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2730 Electromagnetic Modeling of a MESFET Transistor Using the Moments Method Combined with Generalised Equivalent Circuit Method

Authors: Takoua Soltani, Imen Soltani, Taoufik Aguili

Abstract:

The communications' and radar systems' demands give rise to new developments in the domain of active integrated antennas (AIA) and arrays. The main advantages of AIA arrays are the simplicity of fabrication, low cost of manufacturing, and the combination between free space power and the scanner without a phase shifter. The integrated active antenna modeling is the coupling between the electromagnetic model and the transport model that will be affected in the high frequencies. Global modeling of active circuits is important for simulating EM coupling, interaction between active devices and the EM waves, and the effects of EM radiation on active and passive components. The current review focuses on the modeling of the active element which is a MESFET transistor immersed in a rectangular waveguide. The proposed EM analysis is based on the Method of Moments combined with the Generalised Equivalent Circuit method (MOM-GEC). The Method of Moments which is the most common and powerful software as numerical techniques have been used in resolving the electromagnetic problems. In the class of numerical techniques, MOM is the dominant technique in solving of Maxwell and Transport’s integral equations for an active integrated antenna. In this situation, the equivalent circuit is introduced to the development of an integral method formulation based on the transposition of field problems in a Generalised equivalent circuit that is simpler to treat. The method of Generalised Equivalent Circuit (MGEC) was suggested in order to represent integral equations circuits that describe the unknown electromagnetic boundary conditions. The equivalent circuit presents a true electric image of the studied structures for describing the discontinuity and its environment. The aim of our developed method is to investigate the antenna parameters such as the input impedance and the current density distribution and the electric field distribution. In this work, we propose a global EM modeling of the MESFET AsGa transistor using an integral method. We will begin by describing the modeling structure that allows defining an equivalent EM scheme translating the electromagnetic equations considered. Secondly, the projection of these equations on common-type test functions leads to a linear matrix equation where the unknown variable represents the amplitudes of the current density. Solving this equation resulted in providing the input impedance, the distribution of the current density and the electric field distribution. From electromagnetic calculations, we were able to present the convergence of input impedance for different test function number as a function of the guide mode numbers. This paper presents a pilot study to find the answer to map out the variation of the existing current evaluated by the MOM-GEC. The essential improvement of our method is reducing computing time and memory requirements in order to provide a sufficient global model of the MESFET transistor.

Keywords: active integrated antenna, current density, input impedance, MESFET transistor, MOM-GEC method

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2729 Spatiotemporal Modeling of Under-Five Mortality and Associated Risk Factors in Ethiopia

Authors: Melkamu A. Zeru, Aweke A. Mitiku, Endashaw Amuka

Abstract:

Background: Under-five mortality is the likelihood that a baby will pass away before turning exactly 5 years old, represented as a percentage per 1,000 live births. Exploring the spatial distribution and identifying the temporal pattern is important to reducing under-five child mortality globally, including in Ethiopia. Thus, this study aimed to identify the risk factors of under-five mortality and the spatiotemporal variation in Ethiopian administrative zones. Method: This study used the 2000-2016 Ethiopian Demographic and Health Survey (EDHS) data, which were collected using a two-stage sampling method. A total of 43,029 (10,873 in 2000, 9,861 in 2005, 11,654 in 2011, and 10,641 in 2016) weighted sample under-five child mortality was used. The space-time dynamic model was employed to account for spatial and time effects in 65 administrative zones in Ethiopia. Results: From the result of a general nesting spatial-temporal dynamic model, there was a significant space-time interaction effect [γ = -0.1444, 95 % CI (-0.6680, -0.1355)] for under-five mortality. The increase in the percentages of mothers illiteracy [𝛽 = 0.4501, 95% CI (0.2442, 0.6559)], not vaccinated[𝛽= 0.7681, 95% CI (0.5683, 0.9678)], unimproved water[𝛽= 0.5801, CI (0.3793, 0.7808)] were increased death rates for under five children while increased percentage of contraceptive use [𝛽= -0.6609, 95% CI (-0.8636, -0.4582)] and ANC visit > 4 times [𝛽= -0.1585, 95% CI(-0.1812, -0.1357)] were contributed to the decreased under-five mortality rate at the zone in Ethiopia. Conclusions: Even though the mortality rate for children under five has decreased over time, still there is still higher in different zones of Ethiopia. There exists spatial and temporal variation in under-five mortality among zones. Therefore, it is very important to consider spatial neighbourhoods and temporal context when aiming to avoid under-five mortality.

Keywords: under-five children mortality, space-time dynamic, spatiotemporal, Ethiopia

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2728 Electromagnetic Energy Harvesting by Using a Rectenna with a Metamaterial Lens

Authors: Ursula D. C. Resende, Fabiano S. Bicalho, Sandro T. M. Gonçalves

Abstract:

The growing demand for cheap and clean energy sources have been motivated by the study and development of distinct technologies and devices able to provide different amounts of energy. In order to supply energy for small loads, the energy from the electromagnetic spectrum can be harvested. This possibility is particularly interesting because this kind of energy is constantly available in the environment and the number of radiofrequency sources is permanently increasing, due to advances in telecommunications services. A rectenna, which is a combination of an antenna and a rectifier circuit, is an equipment that can efficiently perform the electromagnetic energy harvesting. However, since the amount of electromagnetic energy available in the environment is very small, limited values of power can be harvested by the rectenna. Therefore, several technical strategies have been investigated in order to increase this amount of power. In this work, a metamaterial electromagnetic lens is used to improve the electromagnetic energy harvesting. The rectenna investigated was designed and optimized to charge a Li-Ion battery using the electromagnetic energy from an internet Wi-Fi commercial router model TL-WR841HP operating in 2.45 GHz with maximal output power equal to 18 dBm. The rectenna consists of a high directive antenna, a double voltage rectifier circuit and a metamaterial lens. The printed antenna, constituted of two rectangular radiator elements, was projected and optimized by using the Computer Simulation Software (CST) in order to obtain high directivities and values of S11 parameter below -10 dB in 2.45 GHz. The antenna was printed over a double-sided copper fiberglass substrate, FR4, with characterized relative electric permittivity εr = 4.3 and tangent of losses δ = 0.01. The rectifier circuit, which incorporates a circuit for impedance matching and uses the Schottky diode HSMS-2852, was projected and optimized by using Advanced Design Software (ADS) and built over the same FR4 substrate. The metamaterial cell is composed of two Square Split Ring Resonator (S-SRR) and a thin wire in order to operate with negative values of εr and relative magnetic permeability in 2.45 GHz. In order to evaluate the performance of the purposed rectenna two experimental charging tests were performed, one without and other with the metamaterial lens. The result obtained demonstrate that the electromagnetic lens was able to significantly increase the levels of electric current delivered to the battery, approximately 44%.

Keywords: electromagnetic energy harvesting, electromagnetic lens, metamaterial, rectenna

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2727 Spatial Distribution of Certified Mental Disabilities in China

Authors: Jiayue Yang

Abstract:

Based on an analysis of China's database of certified disabled persons in 2021, this study reveals several key findings. Firstly, the proportion of certified mentally disabled persons among China's certified disabled population (Certification rate 1) shows a decreasing distribution from the East to the West and from the South to the North. Secondly, the spatial distribution of the number of mentally disabled persons per 1,000 people holding certificates (certification rate 2) shows a relatively scattered pattern, with significant variations observed between cities in the eastern region. However, on an overall scale, a south-north gradient can still be observed, with higher rates in the North and lower rates in the west, while the central region demonstrates higher rates compared to the western region. The variation in the rate of mentally handicapped certificates among regions is influenced not only by traditional culture and welfare level but also exhibits a certain correlation with the level of economic development.

Keywords: certified disabled persons, mentally disabled persons, spatial distribution, China

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2726 The Evolution of Spatio-Temporal Patterns of New-Type Urbanization in the Central Plains Economic Region in China

Authors: Sun fang, Zhang Wenxin

Abstract:

This paper establishes an evaluation index system for spatio-temporal patterns of urbanization, with the county as research unit. We use the Entropy Weight method, coefficient variance, the Theil index and ESDA-GIS to analyze spatial patterns and evolutionary characteristics of New-Type Urbanization in the Central Plains Economic Region (CPER) between 2000 and 2011. Results show that economic benefit, non-agricultural employment level and level of market development are the most important factors influencing the level of New-Type Urbanization in the CPER; overall regional differences in New-Type Urbanization have declined while spatial correlations have increased from 2000 to 2011. The overall spatial pattern has changed little, however; differences between the western and eastern areas of the CPER are clear, and the pattern of a strong west and weak east did not change significantly over the study period. Areas with high levels of New-Type Urbanization were mostly distributed along the Beijing-Guangzhou and LongHai Railways on both sides, a new influx of urbanization was tightly clustered around ZhengZhou in the Central Henan Urban Agglomeration, but this trend was found to be weakening slightly. The level of New-Type Urbanization in municipal districts was found to be much higher than it was in the county generally. Provincial borders experienced a lower rate of growth and a lower level of New-Type Urbanization than did any other areas, consistently forming clusters of cold spots and sub-cold spots. The analysis confirms that historical development, location, and diffusion effects of urban agglomeration are the main drivers of changes in New-Type Urbanization patterns in CPER.

Keywords: new-type urbanization, spatial pattern, central plains economic region, spatial evolution

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2725 Spatial Interpolation of Intermediate Soil Properties to Enhance Geotechnical Surveying for Foundation Design

Authors: Yelbek B. Utepov, Assel T. Mukhamejanova, Aliya K. Aldungarova, Aida G. Nazarova, Sabit A. Karaulov, Nurgul T. Alibekova, Aigul K. Kozhas, Dias Kazhimkanuly, Akmaral K. Tleubayeva

Abstract:

This research focuses on enhancing geotechnical surveying for foundation design through the spatial interpolation of intermediate soil properties. Traditional geotechnical practices rely on discrete data from borehole drilling, soil sampling, and laboratory analyses, often neglecting the continuous nature of soil properties and disregarding values in intermediate locations. This study challenges these omissions by emphasizing interpolation techniques such as Kriging, Inverse Distance Weighting, and Spline interpolation to capture the nuanced spatial variations in soil properties. The methodology is applied to geotechnical survey data from two construction sites in Astana, Kazakhstan, revealing continuous representations of Young's Modulus, Cohesion, and Friction Angle. The spatial heatmaps generated through interpolation offered valuable insights into the subsurface environment, highlighting heterogeneity and aiding in more informed foundation design decisions for considered cites. Moreover, intriguing patterns of heterogeneity, as well as visual clusters and transitions between soil classes, were explored within seemingly uniform layers. The study bridges the gap between discrete borehole samples and the continuous subsurface, contributing to the evolution of geotechnical engineering practices. The proposed approach, utilizing open-source software geographic information systems, provides a practical tool for visualizing soil characteristics and may pave the way for future advancements in geotechnical surveying and foundation design.

Keywords: soil mechanical properties, spatial interpolation, inverse distance weighting, heatmaps

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2724 Environmental Resilience in Sustainability Outcomes of Spatial-Economic Model Structure on the Topology of Construction Ecology

Authors: Moustafa Osman Mohammed

Abstract:

The resilient and sustainable of construction ecology is essential to world’s socio-economic development. Environmental resilience is crucial in relating construction ecology to topology of spatial-economic model. Sustainability of spatial-economic model gives attention to green business to comply with Earth’s System for naturally exchange patterns of ecosystems. The systems ecology has consistent and periodic cycles to preserve energy and materials flow in Earth’s System. When model structure is influencing communication of internal and external features in system networks, it postulated the valence of the first-level spatial outcomes (i.e., project compatibility success). These instrumentalities are dependent on second-level outcomes (i.e., participant security satisfaction). These outcomes of model are based on measuring database efficiency, from 2015 to 2025. The model topology has state-of-the-art in value-orientation impact and correspond complexity of sustainability issues (e.g., build a consistent database necessary to approach spatial structure; construct the spatial-economic model; develop a set of sustainability indicators associated with model; allow quantification of social, economic and environmental impact; use the value-orientation as a set of important sustainability policy measures), and demonstrate environmental resilience. The model is managing and developing schemes from perspective of multiple sources pollutants through the input–output criteria. These criteria are evaluated the external insertions effects to conduct Monte Carlo simulations and analysis for using matrices in a unique spatial structure. The balance “equilibrium patterns” such as collective biosphere features, has a composite index of the distributed feedback flows. These feedback flows have a dynamic structure with physical and chemical properties for gradual prolong of incremental patterns. While these structures argue from system ecology, static loads are not decisive from an artistic/architectural perspective. The popularity of system resilience, in the systems structure related to ecology has not been achieved without the generation of confusion and vagueness. However, this topic is relevant to forecast future scenarios where industrial regions will need to keep on dealing with the impact of relative environmental deviations. The model attempts to unify analytic and analogical structure of urban environments using database software to integrate sustainability outcomes where the process based on systems topology of construction ecology.

Keywords: system ecology, construction ecology, industrial ecology, spatial-economic model, systems topology

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2723 The Research of Industrial Space Characteristics, Layout, and Strategy in Metropolitan Area in China: In Case of Wuhan

Authors: Min Zhou, Kaixuan Lin, Yaping Huang

Abstract:

In this paper, the industrial space of metropolitan area in Wuhan is taken as a sample. First of all, it puts forward that the structure of service economy, circle gradient relocation and high degree of regional collaboration are the rules of industrial spatial development in the modern world cities. Secondly, using the economic statistics and land use vector data (1993, 2004, 2010, and 2013) of Wuhan, it analyzes the present situation of industry development and the characteristics of industrial space layout from three aspects of the industrial economic structure, industrial layout, and industrial regional synergy. Then, based on the industrial development regularity of world cities, it puts forward to construct the industrial spatial level of ‘complex industrial concentration area + modular industry unit’ and the industrial spatial structure of ‘13525’. Finally, it comes up with the optimization tactics of the industrial space’s transformation in the future under the background of new economic era.

Keywords: big city of metropolitan area, industrial space, characteristics, layout, strategy

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2722 The Effects of Weather Events and Land Use Change on Urban Ecosystems: From Risk to Resilience

Authors: Szu-Hua Wang

Abstract:

Urban ecosystems, as complex coupled human-environment systems, contain abundant natural resources for breeding natural assets and, at the same time, attract urban assets and consume natural resources, triggered by urban development. Land use change illustrates the interaction between human activities and environments factually. However, IPCC (2014) announces that land use change and urbanization due to human activities are the major cause of climate change, leading to serious impacts on urban ecosystem resilience and risk. For this reason, risk assessment and resilience analysis are the keys for responding to climate change on urban ecosystems. Urban spatial planning can guide urban development by land use planning, transportation planning, and environmental planning and affect land use allocation and human activities by building major constructions and protecting important national land resources simultaneously. Urban spatial planning can aggravate climate change and, on the other hand, mitigate and adapt climate change. Research on effects of spatial planning on land use change and climate change is one of intense issues currently. Therefore, this research focuses on developing frameworks for risk assessment and resilience analysis from the aspect of ecosystem based on typhoon precipitation in Taipei area. The integrated method of risk assessment and resilience analysis will be also addressed for applying spatial planning practice and sustainable development.

Keywords: ecosystem, land use change, risk analysis, resilience

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2721 Multi-Criteria Decision Support System for Modeling of Civic Facilities Using GIS Applications: A Case Study of F-11, Islamabad

Authors: Asma Shaheen Hashmi, Omer Riaz, Khalid Mahmood, Fahad Ullah, Tanveer Ahmad

Abstract:

The urban landscapes are being change with the population growth and advancements in new technologies. The urban sprawl pattern and utilizes are related to the local socioeconomic and physical condition. Urban policy decisions are executed mostly through spatial planning. A decision support system (DSS) is very powerful tool which provides flexible knowledge base method for urban planning. An application was developed using geographical information system (GIS) for urban planning. A scenario based DSS was developed to integrate the hierarchical muti-criteria data of different aspects of urban landscape. These were physical environment, the dumping site, spatial distribution of road network, gas and water supply lines, and urban watershed management, selection criteria for new residential, recreational, commercial and industrial sites. The model provided a framework to incorporate the sustainable future development. The data can be entered dynamically by planners according to the appropriate criteria for the management of urban landscapes.

Keywords: urban, GIS, spatial, criteria

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2720 Enhancing Green Infrastructure as a Climate Change Adaptation Strategy in Addis Ababa: Unlocking Institutional, Socio-Cultural and Cognitive Barriers for Application

Authors: Eyasu Markos Woldesemayat, Paolo Vincenzo Genovese

Abstract:

In recent years with an increase in the concentration of Green House Gases (GHG), Climate Change (CC) externalities are mounting, regardless of governments, are scrambling to implement mitigation and adaptation measures. With multiple social, economic and environmental benefits, Green Infrastructure (GI) has evolved as a highly valuable policy tool to promote sustainable development and smart growth by meeting multiple objectives towards quality of life. However, despite the wide range of benefits, it's uptake in African cities such as Addis Ababa is very low due to several constraining factors. This study, through content analysis and key informant interviews, examined barriers for the uptake of GI among spatial planners in Addis Ababa. Added to this, the study has revealed that the spatial planners had insufficient knowledge about GI planning principles such as multi-functionality, integration, and connectivity, and multiscale. The practice of implementing these holistic principles in urban spatial planning is phenomenally nonexistent. The findings also revealed 20 barriers categorized under four themes, i.e., institutional, socio-cultural, resource, and cognitive barriers. Similarly, it was identified that institutional barriers (0.756), socio-cultural barriers (0.730), cognitive barriers (0.700) and resource barriers (0.642), respectively, are the foremost impending factors for the promotion of GI in Addis Ababa. It was realized that resource barriers were the least constraining factor for enshrining the GI uptake in the city. Strategies to hasten the adoption of GI in the city mainly focus on improving political will, harmonization sectorial plans, improve spatial planning and implementation practice, prioritization of GI in all planning activities, enforcement of environmental laws, introducing collaborative GI governance, creating strong and stable institutions and raising awareness on the need to conserve environment and CC externalities through education and outreach mechanisms.

Keywords: Addis Ababa, climate change, green infrastructure, spatial planning, spatial planners

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2719 A Political-Economic Analysis of Next Generation EU Recovery Fund

Authors: Fernando Martín-Espejo, Christophe Crombez

Abstract:

This paper presents a political-economic analysis of the reforms introduced during the coronavirus crisis at the EU level with a special emphasis on the recovery fund Next Generation EU (NGEU). It also introduces a spatial model to evaluate whether the governmental features of the recovery fund can be framed inside the community method. Particularly, by evaluating the brake clause in the NGEU legislation, this paper analyses theoretically the political and legislative implications of the introduction of flexibility clauses in the EU decision-making process.

Keywords: EU, legislative procedures, spatial model, coronavirus

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2718 An Investigation of the Quantitative Correlation between Urban Spatial Morphology Indicators and Block Wind Environment

Authors: Di Wei, Xing Hu, Yangjun Chen, Baofeng Li, Hong Chen

Abstract:

To achieve the research purpose of guiding the spatial morphology design of blocks through the indicators to obtain a good wind environment, it is necessary to find the most suitable type and value range of each urban spatial morphology indicator. At present, most of the relevant researches is based on the numerical simulation of the ideal block shape and rarely proposes the results based on the complex actual block types. Therefore, this paper firstly attempted to make theoretical speculation on the main factors influencing indicators' effectiveness by analyzing the physical significance and formulating the principle of each indicator. Then it was verified by the field wind environment measurement and statistical analysis, indicating that Porosity(P₀) can be used as an important indicator to guide the design of block wind environment in the case of deep street canyons, while Frontal Area Density (λF) can be used as a supplement in the case of shallow street canyons with no height difference. Finally, computational fluid dynamics (CFD) was used to quantify the impact of block height difference and street canyons depth on λF and P₀, finding the suitable type and value range of λF and P₀. This paper would provide a feasible wind environment index system for urban designers.

Keywords: urban spatial morphology indicator, urban microclimate, computational fluid dynamics, block ventilation, correlation analysis

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2717 Low Trigger Voltage Silicon Controlled Rectifier Stacking Structure with High Holding Voltage for High Voltage Applications

Authors: Kyoung-Il Do, Jun-Geol Park, Hee-Guk Chae, Jeong-Yun Seo, Yong-Seo Koo

Abstract:

A SCR stacking structure is proposed to have improved Latch-up immunity. In comparison with conventional SCR (Silicon Controlled Rectifier), the proposed Electrostatic Discharge (ESD) protection circuit has a lower trigger characteristic by using the LVTSCR (Low Voltage Trigger) structure. Also the proposed ESD protection circuit has improved Holding Voltage Characteristic by using N-stack technique. These characteristics enable to have latch-up immunity in operating conditions. The simulations are accomplished by using the Synopsys TCAD. It has a trigger voltage of 8.9V and a holding voltage of 1.8V in a single structure. And when applying the stack technique, 2-stack has the holding voltage of 3.8V and 3-stack has the holding voltage of 5.1 V.

Keywords: electrostatic discharge (ESD), low voltage trigger silicon controlled rectifier (LVTSCR), MVTSCR, power clamp, silicon controlled rectifier (SCR), latch-up

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2716 Design of Reconfigurable and Non-reciprocal Metasurface with Independent Controls of Transmission Gain, Attenuation and Phase

Authors: Shi Yu Wang, Qian Wei Zhang, He Li, Hao Han He, Yun Bo Li

Abstract:

The spatial controls of electromagnetic (EM) waves have always been a research hot spot in recent years. And the rapid development of metasurface-based technologies has provided more freedoms for manipulating the EM waves. Here we propose the design of reconfigurable and non-reciprocal metasurface with independent controls of transmission gain, attenuation and phase. The proposed meta-atom mainly consists of the cascaded textures including the receiving antenna, the middle layer in which the power amplifiers (PAs), programmable attenuator and phase shifter locate, and the transmitting antenna. The programmable attenuator and phase shifter can realize the dynamic controls of transmission amplitude and phase independently, and the PA devices in the meta-atom can actualize the performance of non-reciprocal transmission. The proposed meta-atom is analyzed applying field-circuit co-simulation and a sample of the meta-atom is fabricated and measured under using two standard waveguides. The measured results verify the ability of the independent manipulation for transmission amplitude and phase of the proposed the meta-atom and the design method has been verified very well correspondingly.

Keywords: active circuits, independent controls of multiple electromagnetic features, non-reciprocal electromagnetic transmission, reconfigurable and programmable

Procedia PDF Downloads 79