bluuebunny/crossref_metadata_2025 huggingface dataset:
Theoretical investigation of Cu influence on the stability characteristics of T-phase in crossover alloys
Authors: Xue Boyu , Xiao Wei , Li Xiwu , Gao Guanjun , Li Xiaowu , Yan Hongwei , Yan Lizhen , Zhang Yongan , Xiong Baiqing
Published: September 2024

In crossover Al-Mg-Zn alloys, the T-phase (Mg32(Al, Zn)49) is crucial for reinforcement. The critical nucleation size of the precipitated T-phase is notably reduced by Cu addition, as well as the activation energy. There is a lack of theoretical research on the influence of Cu elements on the stability of T-phases and mechanical properties. In this work, we systematically investigate the influence of varying Cu concentration on the T-phases by examining their stability, mechanical properties, and electronic structure characteristics through first-principles calculations. The findings reveal that the T-phase maintains lattice stability within the 0 to 5% Cu content range, with a linear decrease in the lattice parameter and formation energy (–0.16 ~ –0.15 eV/atom). Additionally, there is an observable positive correlation trend between the elastic moduli (B, E, and G) of the T-type phase and the Cu content. It is shown that the T-phase exhibits inherent ductility. Analysis based on Pugh’s criterion and Poisson’s ratio indicates a reduction in the ductility with increasing Cu content in the T-phase. This work theoretically validates the previous experimental observations and reveals the impacts of Cu concentration on the T-phase.
Multipeak ultraviolet lasing based on F-P mode from in-situ ZnO nanowire
Authors: Zhang Ying , Liu Ruibin
Published: September 2024

High-quality ultraviolet singlemode and multimode lasing from zinc oxide nanowires are highly desirable. In this paper, we achieve high-Q lasing oscillation in vertically grown Zinc oxide (ZnO) microwires. The broad gain range reaches 13 lasing modes under high-energy excitation. We observe multiple peak emissions from the Fabry-Perot (F-P) lasing mode. In contrast, nanorod arrays with low aspect ratios exhibit amplified spontaneous emission (ASE) due to significant diffraction losses. Our work demonstrates that high-quality ZnO nanowires with an appropriate aspect ratio realize high-Q ultraviolet multipeak lasing based on F-P mode. These findings will benefit the design and fabrication of nanolasers based on nanowires.
Research on the influence of applying counterweight on the deflection and stability of cantilever beam of machine tool
Authors: Jiang Xinguo , Fang Xifeng , Li Zhiduo , Zhang Shengwen
Published: September 2024

The deflection and stability of the cantilever beam of the machine tool are important factors that affect the machining accuracy of the machine tool. Because of the space size, it needs to be weighted within a limited size. By designing different weighting schemes, the static analysis and modal analysis are carried out by finite element analysis software, and the influence law of the deflection and stress of the beam is obtained, so the appropriate weighting scheme is selected. Through the analysis of different schemes, it is known that the deflection of the beam is the smallest under the action of the arm of 900mm and the force of 1000N, and the machine tool structure is more compact, which is the key component of the subsequent machine tool.
Effects of carbon content and heat treatment on wear-resistance and impact properties of novel cast steels with bainitic and martensitic structure
Authors: Tian Xuefeng , Zhang Guozhi , Wang Kun , Yang Xiaobo , Feng Lulu , Yang Weiguang
Published: September 2024

The traditional material for caterpillar boards is mainly Hadfield steel. The wear resistance of the Hadfield steel cannot be fully exerted due to insufficient work hardening during the operation of the caterpillar board. The effects of carbon content and heat treatment on the wear-resistant and impact properties of a novel caterpillar board cast steels with bainitic and martensitic structures have been investigated. The microstructural observation of worn surface topography was performed by scanning an electronic microscope, and the impact toughness was carried out by an impact tester, in a bid to improve the wear-resistant properties and its impact toughness. The results demonstrate that the hardness and wear-resistant properties of cast steels increase with the increase of carbon content, whereas the impact properties reduce because the brittle phases, such as the carbide precipitation and the martensite, are more. The heat treatment temperature of steels can change the relative ratio of bainitic and martensitic structures, thus affecting the wear-resistant properties of the steels. By controlling the carbon content and heat treatment processing of the steels, the optimal combination of toughness and wear-resistant properties can be achieved. The wear mechanism of dual-phase cast steel was analyzed through wear resistance tests, and it also shows that dual-phase cast steel with bainitic and martensitic structures had better wear-resistance properties compared to the Hadfield steel at low-impact wear conditions.
Study on the influence of geometric parameters of typical titanium alloy power milling tools
Authors: Shi Zhonglou , Yang Xiangjie
Published: September 2024

Based on ABAQUS, orthogonal finite element tests were carried out when the number of keyway milling cutter blades was three and four, and the spiral rise angle was 60° and 65°, respectively. The results showed that with the maximum number of blades and spiral rise angle, the milling quality of typical titanium alloy TC4 was greatly improved. The surface roughness decreases, and the effect of spiral lift angle on surface roughness is more significant, which provides a theoretical basis for improving the quality and energy of typical titanium alloy milling tool selection.
Research on the performance optimization of the cam linkage mechanism for marine diesel engines
Authors: Wang Keke , Meng Na , Yang Sen , Chen Longfa , Sun Wenzheng
Published: September 2024

In this paper, the impact of friction and wear in the flat bottom mechanism of a diesel engine on the reliability and durability of the valve train is investigated. A method for establishing a dynamic contact model is proposed, including the establishment of the cam profile equation, force analysis at the contact point, calculation of the curvature radius, and derivation of contact stress. Through the derivation of wear depth and structural optimization analysis, the proposed method can be used to optimize the cam profile and improve the service life and work efficiency of the valve train. The results show that the optimized cam follower’s life is increased by 31.8%, and the contact stress is decreased by 16.5%. This study is of great significance for improving the power and efficiency of diesel engines.
Modelling of a thin-film transistor based on the carbon nanotubes network and ESD circuit simulation by SPICE
Authors: Liao Xianghua , Zeng Weihao , Huang Hao , Wang Qinqin , Zhou Zijie
Published: September 2024

Carbon nanotubes are considered one of the most promising candidate materials for Si. However, there has been limited research on modeling devices based on carbon nanotubes and performing discharge (ESD) protection simulations for circuits composed of carbon nanotube-based devices. Within this article, the current characteristics of network carbon nanotube field-effect transistors (CNT-TFT) with micrometer size are studied, and the devices with channel length L
g = 11 μm and width of W = 108 μm are modelled. It is found that the simulation curves of the model are in good agreement with the experimental results. In this article, the ESD behavior modeling method is introduced. By utilizing this method, a bidirectional diode device model was programmed and integrated into an inverter built with CNT-TFT models. When an ESD positive pulse is applied between the input and ground terminals (PS mode), it is found that the simulation results of the circuit have passed the 500 V human body model (HBM) ESD pulse test in the PS mode, thereby achieving ESD protection simulation for carbon-based integrated circuits.
Optimization of the two-step coating formation process for ZK21 magnesium alloy
Authors: Wang Ruochao , Liu Qing , Liu Hongtao
Published: September 2024

The primary hindrance to the broader utilization of magnesium alloys lies in their insufficient corrosion resistance. This research initiative introduced an advanced two-phase methodology incorporating phosphating and alkali heating to produce a protective Ca-P coating on the surface of magnesium alloys. This innovative approach not only bolsters their corrosion resistance but also facilitates controlled degradation in bodily fluid environments. Following a 60-minute phosphating process in a solution with a pH level of 3, the resultant Ca-P coating achieved full coverage over the magnesium alloy surface, displaying commendable coating density and uniformity. Subsequent treatment with alkali heating for 30 minutes further enhanced the density and smoothness of the coating. Analysis utilizing EDS and XRD revealed that the primary constituents of the phosphate magnesium alloy and the phosphate + alkali heated magnesium alloy coating were DCPD and HA, respectively. Corrosion degradation assessments conducted in SBF solution validated that the two-step coating formation method significantly fortified the corrosion resistance of magnesium alloys.
Comparative study on TD treatment for preparation of VC coating composite processes
Authors: Deng Yutong , Liu Yongyue , Jin Haoxing , Jiang Peng , Chen Hao
Published: September 2024

A VC coating was prepared on the surface of mold steel Cr12MoV using the TD composite treatment process. The differences in microstructure and properties between the two composite treatment processes and the VC coating obtained from the ordinary TD vanadium infiltration process were compared using a microhardness tester, scratch tester, X-ray diffraction, etc. The results show that both composite processes can improve the unevenness of matrix carbides; The hardness of the VC coating obtained by the two composite processes is slightly higher than that of the ordinary TD; The TD+vacuum quenching process has to some extent improved the adhesion between the coating and the substrate; The valence state of the VC coating obtained by the secondary TD process has undergone significant changes.
Statistical regression analysis of bond splitting tensile properties of old and new concrete
Authors: Hou Da , Yuan Dongnan , Wang Keqin , Liu Duo
Published: September 2024

With the gradual increase of assembled and reinforced structures in modern construction, the bonding problem of new and old concrete has become a hotspot of increasing concern for scholars and engineers. Bond tensile properties are the main aspects of bond mechanical properties, and their main influencing factors are interface roughness, old and new concrete strength, roughness treatment, and normal stress. This paper analyses the influence of each factor on bond tensile property by collating a large amount of experimental data from established scholars. The analysis results show that the bond tensile property increases linearly with the increase of roughness and nonlinearly with the rise of new and old concrete strength. Based on summarising the influence law of a single factor, the calculation equation of bond tensile property was proposed. The calculated equations derived from the statistical regression were compared with the formulas of different scholars to analyze the closeness of the experimental and calculated values; the results show that the formula proposed in this paper is more accurate and stable.
Parameter characterization of the PBM-DEM method in numerical simulation of shallow buried mine explosions
Authors: Liu Pengpeng , Ye Hui , Deng Gangfeng , Chen Juan
Published: September 2024

To investigate the impact of various parameters on the numerical simulation of shallow buried mine explosions through the particle explosion method and discrete element method, this paper adopts a coupled method of particle blast method and discrete element method, namely the PBM-DEM method, to simulate the response of AL-6XN stainless steel plate under shallow buried mine explosions. This article first combines the experimental results of Børvik to validate the precision of the PBM-DEM approach. Then, the influence of particle quantity, interaction parameters between sand particles, and interaction parameters between sand particles and plate on the outcomes of the numerical simulations are analyzed. The analysis reveals that as the quantity of explosive particles rises, the central displacement and maximum kinetic energy of the plate escalate. In contrast, these values decrease as the number of sand particles increases. The interaction parameters between sand particles have almost no effect on the numerical simulation results. The damping and stiffness parameters between the sand particles and the plate have a pronounced effect on the numerical simulation results, and the center displacement and peak kinetic energy of the plate rise as the damping and stiffness parameters between the sand particles and the plate increase.
Wearable photonic crystal double network hydrogel sensor based on structural color analysis
Authors: Liu Zhenye , Zhang Wenxin , Qiao Yu , Qiu Lili , Meng Zihui
Published: September 2024

This paper introduces a high-toughness photonic crystal (PhCs) dual-network hydrogel sensor designed for mechanical sensing, which enables quantitative analysis of structural color using the HSB color space. The hydrogel achieves a maximum tensile strain of 250% under a tensile stress of 3.5 MPa, thanks to its dual-network structure comprising a covalently cross-linked polyacrylamide (PAM) network and an ionically cross-linked sodium alginate (SA) network. At an 80% tensile strain, the PAM-SA photonic crystal hydrogel displays a blue shift in the bandgap wavelength of over 130 nm and demonstrates a sensitivity of 1.69 nm/%. The analysis of the force-induced color change in the PAM-SA photonic crystal hydrogel utilized both RGB and HSB color spaces. In the HSB color space, the hue component (H) exhibited a strong linear correlation with strain (R2>0.95), indicating the feasibility of quantitative structural color analysis using HSB. As a wearable sensor, the PAM-SA photonic crystal hydrogel precisely detects human motion via bandgap displacement (R2=0.989) and structural color change (R2=0.978). The PAM-SA PhCs hydrogel, featuring easily accessible color information and high sensitivity, has broad potential applications in wearable devices and mechanical sensors.
Electric Boats for Fisherman as a Substitute for Fuel Oil on The Belitung Island (Indonesia)
Authors: Farisyi Sofwan , Ma’arif Samsul
Published: September 2024

Fishing constitutes a prominent livelihood for many Indonesian coastal residents. Indonesia boasts the world’s longest coastline, which suggests that fishermen should enjoy a high standard of living and a wholesome lifestyle. Nevertheless, a significant portion of traditional Indonesian fishermen fails to experience these benefits, as they persist in outdated fishing practices inherited from their forebears, remaining untouched by the technological advancements that can enhance their economic well-being. This results in elevated operational and maintenance costs during fishing operations. This issue primarily arises from inefficient energy utilization, including fuel, and restricted fuel availability. The objective of this research is to identify solutions to these challenges, particularly by leveraging more efficient technologies to reduce costs and protect fishermen from the health hazards of pollution during their fishing activities. To achieve this research goal, various stages were undertaken, encompassing on-site observations, the design of an electric boat (e-boat) system based on conventional vessels, simulations, and laboratory-scale testing. The testing results indicate that the electric boat, equipped with a 6-kW motor and an 8.64 kWh battery capacity, can be effectively applied in the retrofit process. The initial phase of retrofitting ten electric boats incurs a total cost of $88,620, with each boat’s retrofit expected to yield a return on investment over a span of 20 years. Therefore, this retrofit process necessitates government intervention to provide a 50% subsidy for the electric boat retrofit, subsequently reducing the duration of credit installment payments for fishermen.
Techno-economic comparisons of organic Rankine cycle and supercritical carbon dioxide cycle to utilize brine waste heat in Ulubelu geothermal power plant, Indonesia
Authors: Adven Brilian Vincentius , Khasani  , Pranoto Indro
Published: September 2024

Ulubelu geothermal power plant (GPP) in Indonesia reinjects 2,577 t/h of brine in one of its injection well pads with a temperature of 166°C and a pressure of 7.38 bar. Therefore, the brine still contains considerable waste heat that can be utilized through waste heat recovery (WHR) techniques. Organic Rankine cycle (ORC) and supercritical carbon dioxide (CO2) Brayton cycle (SCBC) are technologies that can be used to convert waste heat into electricity. ORC is already widely used for WHR applications. Meanwhile, SCBC is an emerging technology with the advantage of using CO2 as the working fluid in a closed-loop system. While CO2 is inert and non-flammable, supercritical CO2 has very high specific heat and density, so compact-sized equipment can be used. This study aims to compare the simple ORC, recuperative ORC, simple SCBC, and recuperative SCBC power cycle configurations for brine WHR at the Ulubelu GPP based on the technical and economic aspects. The results show that recuperative ORC produced the highest net output power and thermal efficiency (27,363 kW and 15.96%, respectively). Meanwhile, recuperative SCBC has the best economic performance with the lowest CAPEX (1,404 USD/kW-net), the highest NPV (414.7 million USD) and IRR (29%), and the shortest payback period (4.83 years).
Hydrogen blending with natural gas for combustion efficiency improvement toward decarbonisation of power plants
Authors: Afiq Zubir Muhammad , Hashim Haslenda , Alafiza Yunus Nor , Muhammad Dinie , Yinn Wong Kenn , Kayab Hesam
Published: September 2024

The 12th Malaysia Plan highlighted Malaysia’s commitment to reduce Greenhouse Gas (GHG) emissions by 45% based on Gross Domestic Product (GDP) in 2030 and reach net zero by 2050. To achieve this target, Malaysia has to decarbonise the energy sector as it is the primary emission source, contributing up to 75% of GHG emissions in Malaysia. Hydrogen fuel is getting much attention globally, and it has been said that it can be a new renewable energy source to replace fossil fuels. Hydrogen combustion is clean and only produces water and energy. However, several studies have identified that hydrogen combustion could produce NOx, which is more harmful to the environment than CO2. Studies on hydrogen application in the energy sector in Malaysia are limited, and the implementation of total hydrogen fuel in power plants may not happen shortly. Hence, a fundamental study was proposed on co-firing hydrogen and natural gas fuel. This study aimed to examine co-firing characteristics such as temperature, pressure, and air-to-fuel ratio on GHG emission and energy release to find the optimum natural gas-to-hydrogen ratio. The model was developed using Aspen Plus, and hydrogen-natural gas blend percentages varied from 0% to 30%. The findings showed that increased operating temperature led to higher NOx formation, while varying pressures did not impact the CO2 and NOx formation. The pure natural gas combustion system was more sensitive towards air-to-fuel ratio changes, and an increase in air-to-fuel ratio to 1.5 led to 160% higher NOx formation due to an increase in nitrogen content. The combustion of the hydrogen blend led to lower CO2 formation but higher NOx formation. Lastly, the energy released by the hydrogen blending system was lower due to the formation of water that absorbed the heat released by the combustion.
Potential Utilization of Tamblang Dam for Micro Hydro Power Plant to Increase Renewable Energy Mix for Indonesia
Authors: Putri P I D , Nuraga I K , Ariana I K A , Sugarayasa I W , Paramartha I G N D , Suryanti I , Abiyasa A P
Published: September 2024

Bali, a prominent tourist destination in Indonesia, faces an increasing demand for electricity, primarily supplied by non-renewable sources. With a target to increase renewable energy mix, Bali focuses on leveraging its water resources, notably Tamblang Dam, for hydroelectric power generation. This research aims to determine the potential utilization of Tamblang Dam as a micro hydro power plant, highlighting its capacity to significantly contribute to renewable energy mix in Indonesia generally and Bali particularly. Analysis reveals a potential electricity generation of 0.52 MW, with an annual hydro power production estimate of 4.57 GWh. Considering discharge availability, height of falling water and efficiency of hydro power system. The research also underscores the project’s economic viability and profitability, emphasizing its role in fostering sustainable energy practices in the region.
Pioneering Energy Digitalisation: Revolutionizing Accessibility Initiated by Pertamina Plaju Refinery
Authors: Krisna Prabatha Daniswara , Handoyo Seger , Suryanto  , Gusti Al Hakim Maulana
Published: September 2024

The oldest and less technologically advanced among Pertamina’s refineries, Pertamina Plaju Refinery, faced challenges in maintaining efficiency and competitiveness. However, the introduction of the PROFIT (Plant Performance Operations and Financial Tracking) mobile application transformed the refinery’s operations. With a focus on energy security and real-time data, PROFIT empowered engineers to make informed decisions, enhancing overall performance and productivity. The study employed a descriptive qualitative research design with a case study strategy. Data was collected through interviews and supplemented with secondary sources from the Pertamina library, ensuring data validity. The COVID-19 pandemic accelerated the development of PROFIT, emphasizing the urgency of digitalization in the oil and gas industry. Additionally, the transition to a younger workforce influenced its creation. PROFIT’s advantages in enhancing employee performance were evident, streamlining processes and increasing job satisfaction. The study highlighted its role as a strategic information system. The transformation of Pertamina Plaju Refinery serves as a pioneer for integrated information systems in the industry, promoting progress and sustainability. Embracing digital solutions can drive advancements and improvements in the Indonesian oil and gas sector, optimizing operations and contributing to a more sustainable energy landscape.
Unveiling the influence of financial slack on carbon performance: insights from firms in Malaysia’s smart cities
Authors: Abd Rahman N R , Mustapa S I , Jaaffar A H , Othman N. S , Mohamad M , Atif M
Published: September 2024

As carbon emissions in lower-income countries are projected to rise and surpass those of higher-income countries, they face mounting political pressure to fulfil their commitments under international agreements. As a key participant in carbon emissions abatement, firms can have a strong effect on carbon emissions reduction. However, the successful implementation of carbon emission reductions may hinge on the financial slack of firms. This study investigates the impact of financial slack on the carbon performance of Malaysian smart city firms. The sample includes 64 firms located in four smart cities within the ASEAN Smart City Network (ASCN). The analysis is based on data compiled in 2021, with carbon performance data obtained from the annual reports of firms and financial data obtained from the DataStream Refinitiv Eikon platform. Using regression analysis, the results indicate that financial slack has no significant effect on the carbon performance of Malaysian smart city firms. This study contributes to the growing body of knowledge on financial slack and carbon performance in smart cities. The findings could be beneficial for practitioners and policymakers concerned with improving financial flexibility and reducing carbon emissions.
The Asymmetry of ASEAN Law: Unsustainable Development Phenomenon of Transformative State Enterprise in Case of Cross-border Power Plant Projects
Authors: Luekitinan Pimnada
Published: September 2024

This article aims to study regional law related to manipulating cross-border environmental impact from the phenomenon of cross-border power plants invested by Thai state enterprises. The writer uses qualitative research methods by using 3 concreted case studies of cross-border power plants located on the neighboring countries’ border with Thailand. The company becomes a way for the state to transform its identity from a “state enterprise” to a “private company” for investing in other countries. As a private company, the role of these transformative state enterprises in business has increased significantly; investor, buyer, and seller while maintaining the role of the state in basic public utilities. Any action of these transformative state enterprises has no abuse of sovereignty and no responsibility at the regional level, although, many researchers have shown that the power plant is a cause of gigantic environmental impact. This article shows how state enterprise becomes transformative state enterprise and the asymmetry of ASEAN law between transnational economics and cross-border environmental impact.
Optimizing column location in flat slab system using Particle Swarm Optimization vs Genetic Algorithms
Authors: Zakhera A , Salem S , Torky A A
Published: September 2024

One of the key architectural advantages of a concrete flat slab system is its flexibility in design. The absence of beams and columns allows for larger, open spaces with minimal obstructions, giving architects the freedom to create unique and innovative layouts. However, the location of the middle columns (one of the main factors affecting the construction cost) is commonly aligned based on experience which may entail an uneconomic design alternative. This paper aims to propose different machine learning optimization algorithms, namely, particle swarm optimization (PSO) and genetic algorithms (GA) to optimize the location of columns within a flat slab plan considering different serviceability requirements. Both optimization systems showed good performance for allocating the concrete columns, However, the GA algorithm showed better results in terms of maximum deflection with less computational effort.
Towards the Enhancement of Buildings’ Sustainability: IoT-Based Building Management Systems (IoT-BMS)
Authors: Mostafa Basma , Ahmed Sherif , Ghoniemy Tarek , Al-Sakkaf Abobakr
Published: September 2024

The building sector is the primary consumer of energy, especially electricity. Energy consumption results in greenhouse gas emissions, depletion of natural resources, and finance consumption. Nowadays, buildings are increasingly expected to meet higher and more complex performance requirements. Among these requirements, energy efficiency is recognized as an international goal to promote energy sustainability. Therefore, monitoring, controlling, and managing energy are the key goals of building management that opt for energy efficiency and cost-effective operation and maintenance, which are the main objectives of sustainable development goals. The building sector is significant in its function and requires more energy to operate and maintain, especially for lighting, achieving appropriate thermal comfort, and managing IT systems and other equipment. The reliability and flexibility offered by wireless technologies have been the driving force toward the vision of the Internet of Things (IoT). They have contributed to attracting growing interest in the market. This work presents an energy-efficient IoT solution to monitor the energy consumption model by deploying a Building Management System (BMS). Integrating multiple battery-operated sensors into the building allows critical data to be dynamically provided in real-time to improve overall building efficiency. Introducing the IoT in managing energy in buildings can be more cost-effective and convenient than traditional building BMSs.
Neighborhood housing design using fifth generation manifesto towards nearly zero energy urban developments
Authors: Fahmy Mohammad , Essam Bassel , Elshafei Mohamed
Published: September 2024

Since cities are growing faster than ever before, this paper traces directly that the fifth generation of sustainable city dimensions is not a prosperous idea or a welfare mode of sustainability but a vital effective way to adapt to Climate change, provide energy production, increase carbon reduction, and enhance pedestrian-occupant thermal comfort. It is a systematic method to alleviate urban canyon temperatures, maximize shading in summer, enhance energy production, and minimize heat transfer. It shows better results than designing apartment buildings with parcel planning with its four wall surfaces absorbing heat all day long. Early from schematic design, the emphasis is based on freehand sketching, adjusting urban aspect ratio, courtyard housing closure ratio, compactness degree, and microclimatic orientation, then adding a layer of humanization with green corridors, and tree species numerically modeled based on microclimate with courtyarded passive housing clusters, moving towards detailed design execution with SCEB bearing wall construction having the majority of its mixture of clay which enhances thermal mass insulation, climate adaptation, indoor thermal comfort, and a green job opportunity. Afterward adding energy plus BIPV on the whole constructed microclimatic-based roof to twist the neighborhood into a power bank saving energy consumption, and to work as a double roof shading. It shows on the other urbanism coin side walkability, sequential visual order, urban identity, and architectural character. Numerical outdoor-indoor coupled simulations took place using Envi-met and DesignBuilder while meteorological and biometeorological parameters were measured. The new recipe ignites a sense of harmonizing results in enhancing environmental sustainability measures.
Assessing indoor temperature control using different materials and designs
Authors: Micheal A
Published: September 2024

Controlling indoor temperature in buildings is gaining much importance. This is attributed to the increasing awareness around the world of the mandate reduction in fossil fuel consumption to produce electricity necessary to control temperature inside buildings. This research studies the potential to improve the indoor environment of buildings using different materials either insulators or incorporated inside a building and façade design. The study involves phase changing materials (PCM), thermal insulation materials and façade shading and design. Thermal insulation materials include mineral wool and polystyrene boards, which are the most popular insulators in arid countries. Wood cladding influence on the indoor temperature is also studied. To investigate the effect of facade design on the indoor temperature, two shading devices are used; horizontal and vertical shading elements and a combination of both. Furthermore, the effect of window to wall ratio on the indoor temperature is also studied. To conduct the investigation, an experimental simulation for a 1:5 scaled 3mx3mx3m room is performed. The effect of solar heat is simulated using a sun simulator. Different combinations are investigated to develop guidelines for the engineers to foster the incorporation of materials/design combinations to reduce the users’ dependency on the active techniques to control indoor temperature.
The Impact of Smart Materials Usage in Buildings Envelope: an Approach to Investigate Energy Consumption Versus The Aesthetics Forming The City Image in New Agglomerations
Authors: Awad Abdelhamed Soliman Samar , Nayer Aida
Published: September 2024

The notion of creating New Agglomerations often demonstrates the challenge between maintaining city’s identity and the necessity to adopt contemporary building materials. The main target in the current era is to monitor the degree of sustainable strategies adopted while defining the potential materials used whether in the construction process or for final building envelopes. This study aims to evaluate the implications of energy-saving potential of smart glazing materials in building envelopes through a comparative analysis creating the emergent city image created by building façade systems. A thorough review presents various types of smart glazing materials performance versus traditional glazing systems, in terms of heating and cooling results. The research presents a case study of actual buildings deploying smart glazing systems to provide real-world evidence of their energy-saving potential. The results showed that smart glazing materials can significantly reduce energy consumption compared to traditional glazing systems. The results also indicated that the performance of smart glazing materials varies with different types of materials, and the specific energy-saving potential depends on factors such as building orientation, glazing area, and climate conditions. This study provides insights related to emergent design decisions for new agglomerations in terms of energy-efficient building envelopes and energy consumption strategies.
Challenges of Implementing Integrated Project Delivery in the Construction Industry in Egypt
Authors: Refahy D F , Othman A A E , Nessim A A
Published: September 2024

The construction industry, being one of the biggest sectors globally, has a crucial part to play in achieving global sustainability goals. However, it faces criticism for practices that impede sustainability in construction projects. This is often attributed to the continued reliance on traditional construction methods and contracts, which typically separate design and construction phases. This separation hampers communication among project stakeholders and hinders construction professionals from offering feedback to improve project performance. Despite various efforts to address the shortcomings of traditional procurement methods and contracts, this issue persists. Integrated Project Delivery (IPD) offers a fresh strategy that combines people, systems, business models, and practices to boost value for clients, reduce waste, encourage teamwork, and increase efficiency throughout the entire project. Nonetheless, integrating this approach into the construction sector in Egypt and the MENA region encounters several hurdles. This study aims to explore the challenges associated with implementing IPD in Egypt’s construction industry. This research employs a qualitative approach, grounding its findings in a thorough review of literature and detailed case studies. It explores the nature of the construction industry, sustainability efforts, construction contracts, and IPD. Furthermore, it includes an analysis of three case studies to shed light on the benefits of implementing IPD in construction projects.
Artificial Intelligence Towards Enhancing the Risk Management Practices During the Design Process
Authors: Algheetany N , Othman A A E , Alamoudy F O
Published: September 2024

The design process across various industries involves intricate decision-making, problem-solving, and consideration of multiple factors. However, risks during the design process can jeopardize project success and lead to costly errors. Traditional risk management approaches in design often rely on manual & computerized analysis, which is time-consuming, limited in scope, and prone to human biases. The emergence of artificial intelligence (AI) presents an opportunity to revolutionize risk management in design. AI algorithms can process vast amounts of data, identify patterns, and provide predictive insights, enhancing risk identification and mitigation. This research aims to investigate the relationship between design risks and AI towards enhancing the risk management process. Using a mixed methodology approach, a qualitative method was used through investigating previous literature to identify traditional risk management limitations, design risks and AI tools and methods. Secondly, relationship between identified risks and AI tools was proposed. This was followed by quantitative method through case studies analysis that assess the validity of the proposed relationship. The goal is to establish a new paradigm where AI and risk management converge to create a future where risks that occur during the design process can effectively be identified and managed, fostering innovation and improving project outcomes.
A novel compact xerographic system for 3D printing of fluoropolymer powders onto metal surfaces
Authors: Ryu Hyung Ju , Chen Yiting , Chen Aotian , Moeinnia Hadi , Nemir Omar , Khan Sami , Kim Woo Soo
Published: September 2024

This study introduces a compact xerographic 3D printing system that utilizes precise layer-by-layer dry powder transfer techniques, facilitating the fabrication of 3D objects directly on metal substrates. By leveraging electrostatic force to coat dry fluoroethylene vinyl ether powder onto metallic surfaces, our innovative method significantly broadens the spectrum of printable materials. Through the optimization of electrostatic potentials and powder transfer efficiency, the system successfully demonstrates the ability to produce intricate 3D structures with heights ranging from millimeters to centimeters. This novel approach not only showcases the potential for creating flexible electronic materials with complex 3D geometries directly on the metal substrate but also opens new avenues for diverse material applications within the field of advanced xerographic 3D printing technology.
Mechanism and manufacturing of 4D printing: derived and beyond the combination of 3D printing and shape memory material
Authors: Feng Pei , Yang Feng , Jia Jiye , Zhang Jing , Tan Wei , Shuai Cijun
Published: September 2024

Four-dimensional (4D) printing is regarded as a methodology that links 3D printing to time, which is characterized by the evolution of predetermined structures or functions for the printed object after applying stimulation. This dynamic feature endows 4D printing the potential to be intelligent, attracting wide attention from academia and industry. The transformation of shape and function is both obtained from the programming of the object endowed by the intrinsic characteristics of the material or by the manufacturing technology. Therefore, it is necessary to understand 4D printing from the perspective of both mechanism and manufacturing. Here, the state-of-the-art 4D printing polymer was summarized, beginning with the classifications, and leading to the mechanisms, stimulations, and technologies. The links and differences between 4D printing polymer and shape memory polymer, between 4D printing and 3D printing were highlighted. Finally, the biomedical applications were outlined and the perspectives were discussed.
Research on temperature performance prediction of vortex tubes based on artificial neural networks
Authors: Han Zhihong , Li Shenshen , Liu Shuyang , Gan Dejun , Huang Zhiyuan , Li Qiang , Zhang Jian
Published: September 2024

This study constructs a hybrid neural network model by integrating the physical constraints of the Bernoulli equation and Nikolaev’s formula. The model is designed to explore and predict the variation pattern of the cold end temperature in a vortex tube. The input parameters include inlet pressure, inlet temperature, and cold mass fraction, with the cold end temperature as the output parameter. The network employs a multilayer feedforward model and the Levenberg–Marquardt learning algorithm, using a hyperbolic tangent function as the activation function. To evaluate the statistical validity of the developed model, the coefficient of determination (R2) and root mean square error (RMSE) are utilized, along with an analysis of the model’s uncertainty and robustness. The hybrid model achieves an R2 of 0.9936 and an RMSE of 0.3392, demonstrating strong performance in terms of uncertainty and robustness. These results indicate that the model accurately predicts the cold end temperature variation in the vortex tube. Furthermore, the findings reveal an optimal pressure range (0.49 MPa to 0.76 MPa) and cold mass fraction range (0.1 to 0.2) that minimize the cold end temperature.
UWB distance estimation errors in (non-)line of sight situations within the context of 3D analysis of human movement
Authors: Yogesh Vinish , Rook Jan Willem A , Keizers Thomas , Voort Carsten , Buurke Jaap H , Veltink Peter H , Baten Chris T M
Published: September 2024

Integrated Ultrawideband (UWB) and Magnetic Inertial Measurement Unit (MIMU) sensors are becoming popular for indoor localization applications, as a higher accuracy can be achieved than with just MIMU sensors. These integrated sensors could extend stability and accuracy in the field of 3D analysis of human movement (3D AHM) if they can deliver position estimates with an accuracy close to 1 cm. Achieving this high accuracy of 1 cm remains challenging, with most studies reporting position estimation errors around 5 cm, often due to Non-Line of Sight (NLOS) conditions and systematic UWB sensor distance estimation errors. Studying the distance error characteristic of UWB in situations of 3D AHM is essential to deal with these errors. While research on UWB distance errors in Line of Sight (LOS) and NLOS situations exists, few studies focus on the NLOS errors caused by the human body and were not in the relevant scenarios of 3D AHM. Therefore, this article examines UWB sensor performance and distance error characteristics in LOS and NLOS situations typical for the 3D AHM. Both the LOS and NLOS situations were studied in the typical 3D AHM distance range of 0.2 m to 2 m. The NLOS situations were studied first with a human subject as NLOS causing object and then with simulated human body segments (PVC pipes filled with water) of varying diameters. In LOS situations, consistent systematic bias errors were observed, along with incidental errors at specific positions in the room. In NLOS scenarios caused by the human and simulated body segments, a consistent and reproducible overestimation of distances was found. The reproducibility of these errors based on relative node and object positions suggests that systematic mitigation methods could significantly reduce errors, enabling more accurate and reproducible 3D human movement analysis.
Effect of exo-fiber ring, volume fraction and moisture on the mechanical properties of the 3D printed onyx-carbon fiber composite: an experimental study
Authors: Kiran Mudavath Uday , Punna Eshwaraiah
Published: September 2024

The present study investigates the potential of onyx-carbon fiber composites for automotive applications, like bumpers focusing on mechanical properties and water absorption behaviour. The study involves tensile, compression, and flexural tests, alongside water absorption analysis, to determine the optimal composite configuration. Results indicate that higher carbon fiber volume fractions (10%–15%) and multiple concentric layers (exo-fibers) (3–4) significantly enhance the mechanical performance. The configuration of three concentric layers with 15% carbon fiber demonstrates superior tensile strength, compressive strength, and flexural strength, along with minimal long-term water absorption. This configuration offers a balanced combination of high strength, energy absorption, and durability, making it ideal for enhancing vehicle safety and performance. Future research should focus on optimizing manufacturing techniques and exploring smart material integration to further improve the adaptive properties and damage detection capabilities of these composites, paving the way for next-generation automotive technologies.
Symbolic Dynamics for Nonuniformly Hyperbolic Maps with Singularities in High Dimension
Authors: Araujo Ermerson , Lima Yuri , Poletti Mauricio
Published: September 2024

We construct Markov partitions for non-invertible and/or singular nonuniformly hyperbolic systems defined on higher dimensional Riemannian manifolds. The generality of the setup covers classical examples not treated so far, such as geodesic flows in closed manifolds, multidimensional billiard maps, and Viana maps, and includes all the recent results of the literature. We also provide a wealth of applications.
Amenability and Weak Containment for Actions of Locally Compact Groups on 𝐶*-Algebras
Authors: Buss Alcides , Echterhoff Siegfried , Willett Rufus
Published: September 2024

In this work we introduce and study a new notion of amenability for actions of locally compact groups on

C
∗

C^*

-algebras. Our definition extends the definition of amenability for actions of discrete groups due to Claire Anantharaman-Delaroche. We show that our definition has several characterizations and permanence properties analogous to those known in the discrete case. For example, for actions on commutative

C
∗

C^*

-algebras, we show that our notion of amenability is equivalent to measurewise amenability. Combined with a recent result of Alex Bearden and Jason Crann, this also settles a long standing open problem about the equivalence of topological amenability and measurewise amenability for a second countable

G
G

-space 

X
X

.

We use our new notion of amenability to study when the maximal and reduced crossed products agree. One of our main results generalizes a theorem of Matsumura: we show that for an action of an exact locally compact group

G
G

on a locally compact space

X
X

the full and reduced crossed products

C
0

(
X
)

⋊

m
a
x

G

C_0(X)\rtimes _\mathrm {max}G

and

C
0

(
X
)

⋊

r
e
d

G

C_0(X)\rtimes _\mathrm {red}G

coincide if and only if the action of

G
G

on

X
X

is amenable. We also show that the analogue of this theorem does not hold for actions on noncommutative

C
∗

C^*

-algebras.

Finally, we study amenability as it relates to more detailed structure in the case of

C
∗

C^*

-algebras that fibre over an appropriate

G
G

-space

X
X

, and the interaction of amenability with various regularity properties such as nuclearity, exactness, and the (L)LP, and the equivariant versions of injectivity and the WEP.
Amyotrophic lateral sclerosis as a disease model of sarcopenia
Authors: Azzolino Domenico , Piras Rachele , Zulueta Aida , Lucchi Tiziano , Lunetta Christian
Published: September 2024

Sarcopenia, the progressive decline of muscle mass and function, has traditionally been viewed as an age-related process leading to a broad range of adverse outcomes. However, it has been widely reported that sarcopenia can occur earlier in life in association with various conditions (i.e. disease-related sarcopenia), including neuromuscular disorders. As early as 2010, the European Working Group on Sarcopenia in Older People included neurodegenerative diseases characterised by motor neuron loss among the mechanisms underlying sarcopenia. Despite some differences in pathogenetic mechanisms, both amyotrophic lateral sclerosis (ALS) and age-related sarcopenia share common characteristics, such as the loss of motor units and muscle fibre atrophy, oxidative stress, mitochondrial dysfunction and inflammation. The histology of older muscle shows fibre size heterogeneity, fibre grouping and a loss of satellite cells, similar to what is observed in ALS patients. Regrettably, the sarcopenic process in ALS patients has been largely overlooked, and literature on the condition in this patient group is very scarce. Some instruments used for the assessment of sarcopenia in older people could also be applied to ALS patients. At this time, there is no approved specific pharmacological treatment to reverse damage to motor neurons or cure ALS, just as there is none for sarcopenia. However, some agents targeting the muscle, like myostatin and mammalian target of rapamycin inhibitors, are under investigation both in the sarcopenia and ALS context. The development of new therapeutic agents targeting the skeletal muscle may indeed be beneficial to both ALS patients and older people with sarcopenia.