In the oil and gas industry, operations in greenfield sites are straightforward. However, there are increased risks, such as damage to existing facilities, unknown site conditions, and other complexities in brownfield...In the oil and gas industry, operations in greenfield sites are straightforward. However, there are increased risks, such as damage to existing facilities, unknown site conditions, and other complexities in brownfield sites. In addition to these physical risks, task scheduling is also complex, as vessels need to be replaced during a turnaround. To mitigate the risks of site conditions and realize a truncated schedule for Saudi Aramco’s operations, 3D laser scanning was combined with 3D modeling, clash detection, and time. This integrated approach minimized the shutdown period, which resulted in cost savings, heightened safety, and enhanced stakeholder communications.展开更多
Despite the fact that applying constructability concepts in building designs have led to savings estimated within a range of 1% to 14% of the capital cost, the construction industry still lacks an advanced tool to ass...Despite the fact that applying constructability concepts in building designs have led to savings estimated within a range of 1% to 14% of the capital cost, the construction industry still lacks an advanced tool to assess and check for constructability implementations in designs. Therefore, the objective of this research is to propose a quantitative assessment of building constructability, which transforms the subjective assessment of constructability knowledge to a quantified value so that it is easy to analyze and improve building design. The proposed methodology uses the advancement of object oriented Building Information Model (BIM) and 4D simulation model to serve as a data repository models for the constructability assessment platform. Factors affecting constructability of building designs have been identified and relatively weighted using Analytical Hierarchy Process (AHP) technique based on a questionnaire survey collected throughout the Canadian provinces. Evaluation criteria are also developed to assist the designer to evaluate the design proposals. The outcome shows that the proposed method provides the designer an accurate and faster mode in evaluating project constructability by using the parametric features from BIM and taking the advantage of spatial relationship between building components.展开更多
Extrudability and constructability are two important,yet contradictory issues pertaining to the construction of three-dimensional(3D)printing concrete.Extrudability is easily achieved when 3D printing cement mortar ha...Extrudability and constructability are two important,yet contradictory issues pertaining to the construction of three-dimensional(3D)printing concrete.Extrudability is easily achieved when 3D printing cement mortar has a high water content and low cohesion,but the printed structure is easily collapsible.However,a 3D printing cement mortar with a low water content and high cohesion has a relatively stable printed structure although the cement mortar might not be extrudable.This study proposes a particle-based method to simulate 3D printing mortar extrusion and construction as an overall planning tool for building design.First,a discrete element model with time-varying liquid bridge forces is developed to investigate the microscopic effects of these forces on global rheological properties.Next,a series of numerical simulations relevant to 3D printable mortar extrudability and constructability are carried out.The study demonstrates that the effects of time-varying liquid bridge forces on rheological properties and the resulting extrudability and constructability of 3D printing mortar are considerable.Furthermore,an optimized region that satisfies both the extrusion and construction requirements is provided for 3D printing industry as a reference.展开更多
With the ongoing depletion of fossil fuels,energy and environmental issues have become increasingly critical,necessitating the search for effective solutions.Catalysis,being one of the hallmarks of modern industry,off...With the ongoing depletion of fossil fuels,energy and environmental issues have become increasingly critical,necessitating the search for effective solutions.Catalysis,being one of the hallmarks of modern industry,offers a promising avenue for researchers.However,the question of how to significantly enhance the performance of catalysts has gradually drawn the attention of scholars.Defect engineering,a commonly employed and effective approach to improve catalyst activity,has become a significant research focus in the catalysis field in recent years.Nonmetal vacancies have received extensive attention due to their simple form.Consequently,exploration of metal vacancies has remained stagnant for a considerable period,resulting in a scarcity of comprehensive reviews on this topic.Therefore,based on the latest research findings,this paper summarizes and consolidates the construction strategies for metal vacancies,characterization techniques,and their roles in typical energy and environmental catalytic reactions.Additionally,it outlines potential challenges in the future,aiming to provide valuable references for researchers interested in investigating metal vacancies.展开更多
With the rapid development of globalization and information technology,intellectual property has been one of the key drivers of economic growth,and the construction of intellectual property system has become an import...With the rapid development of globalization and information technology,intellectual property has been one of the key drivers of economic growth,and the construction of intellectual property system has become an important criterion for measuring the quality of business environment.This article is intended to explore the current status of intellectual property system construction in China,the challenges,and its relationship with the business environment,to propose the corresponding countermeasures and suggestions.The study finds that the legal system of intellectual property in China is gradually improving,and judicial and administrative protection are continuously strengthened.However,the challenges still remain such as frequent infringements,rights hard to protect and insufficient international cooperation.These issues not only affect the legitimate rights and interests of innovation entities,but also for the market fairness and the level of the business environment.Therefore,this article proposes that strengthening the perfection of the intellectual property legal system,enhancing intellectual property services and support capabilities,strengthening international cooperation and exchanges,and accelerating the cultivation of composite talents.It aims to provide theoretical references for the construction of intellectual property system and the optimization of the business environment,promote the high-quality development of economy and enhance the global competitiveness of the country.展开更多
Professional and trade skills are required for handling the construction related projects;Construction industries of the present day however lack useful information concerning different practices,patterns and trends i...Professional and trade skills are required for handling the construction related projects;Construction industries of the present day however lack useful information concerning different practices,patterns and trends involved in risk management.Considering this,the present study focuses on the aforementioned variables of risk management by quantitative analysis specifically in the domain of construction industry.This study has used IBM’s SPSS(Statistical Package for Social Sciences)version 25.0 to analyze the results.This study is an initiative to assess the impact of risk management in the construction sector of Jordan.It will assist the construction sector for exploring the limitations with respect to integrate effective risk management.A sense of competition will be developed through a comparison of risk factors of construction projects among the project stakeholders such as contractors should enhance their risk management practices.展开更多
The increasing cost of infrastructure development risks stifling national investment plans.Many projects in Uganda have suffered because of the frequency and magnitude of claims made by parties involved especially the...The increasing cost of infrastructure development risks stifling national investment plans.Many projects in Uganda have suffered because of the frequency and magnitude of claims made by parties involved especially the contractors.As a result,the construction industry is plagued with claims which quite often lead to adversarial relationships.The major grounds for claims were identified through studying the contract documents where claims had been made.Increase in scope;change orders;errors in contract documents;inclement weather;inflation;delay in possessing the site;and change in the tax policy were the most prevalent grounds for making claims.Problems identified in claiming process include delays in getting approval;information on claims not reliable;hostility from the parties involved;pricing of claims;delays in effecting payment when approved;and overzealous contract interpretation leading to misunderstanding and delays Using a survey on project managers for 64 contractors and their corresponding clients or their representatives,the major ways in which it can be reduced were identified as being thoroughness during the design phase;providing for inflation;proper planning of works;using prequalified contractors;and proper documentation of records.Clients have a big role to play in reducing claims.展开更多
In the process of cultural and tourism project construction,intelligent construction technology has gradually shown strong advantages.The effective application of this technology not only greatly improves the construc...In the process of cultural and tourism project construction,intelligent construction technology has gradually shown strong advantages.The effective application of this technology not only greatly improves the construction efficiency and quality of cultural and tourism projects,but also effectively controls construction costs,laying a solid foundation for the green,low-carbon,and sustainable development of the cultural and tourism industry.The article analyzes the current situation of cultural and tourism project construction,proposes the advantages of intelligent construction and its application in the construction mode of cultural and tourism projects,aiming to provide reliable guidance for the sustainable development of cultural and tourism projects.展开更多
The aim of this study is to enhance the value of local earth materials used in the construction of certain homes in the Republic of Guinea. Thus, a trial study to improve the quality of mud bricks using paper fibers o...The aim of this study is to enhance the value of local earth materials used in the construction of certain homes in the Republic of Guinea. Thus, a trial study to improve the quality of mud bricks using paper fibers obtained by grinding and soaking in water and then drying were used as a stabilizer in the manufacture of these mud bricks from the sample of two sites Dounkiwal (DK) (in Mamou and the sample from the urban commune of Kouroussa). To do this, certain methods and means of identification were carried out, namely: geotechnical, mineralogical and chemical analyses. Sample DK from Mamou has a silty-clay geotechnical characteristic with a plasticity index Ip of 12.75%. However, mineralogical and chemical studies showed that sample Dounkiwal (DK) (Mamou) contains a high proportion of silica and iron oxides (79.63%) and Fe2O3 (11.85%), associated with other alkaline earth oxides and ions: CaO;MgO;SO32−;Cl−, i.e. 3.96%;0.96%;0.28% and 0.039% respectively. Its loss on ignition (LOI) and insoluble residues are 15.40% and 56.36%. The evaluation of the number of huts in Upper and Middle Guinea showed that the populations of these areas have been using mud bricks for several decades in the construction of dwellings. The average value found for the compressive strength of these bricks (from samples I, II and III from Kouroussa) is 0.16 MPa. This value is appreciable in the construction of mud houses.展开更多
Clays are a constituent of the earth. As a result, the discovery and traditional use of clays in construction and pottery worldwide dates back to antiquity. Guinea has several deposits of clay minerals whose chemical ...Clays are a constituent of the earth. As a result, the discovery and traditional use of clays in construction and pottery worldwide dates back to antiquity. Guinea has several deposits of clay minerals whose chemical and mineralogical compositions have been little studied. Despite lacking of scientific data on these clay minerals, they are used today in pottery and habitat construction. As a step towards promoting the use of clay materials in Guinea, we conducted a study of the physicochemical and mineralogical properties of three natural clays from Kakan in the Republic of Guinea (AKKB, AKKE, AKKO) used in habitat construction. The aims of this work were to better understand their properties, but above all to be able to act on them to improve and broaden their applications, which until now have been limited to construction. These clays were studied by X-ray diffraction (XRD), X-ray fluorescence spectrometry (XRF), moisture content (%W), laser granulometry, Atterberg limits, specific surface area, infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), thermogravimetric analysis and differential thermal analysis (TGA/DTA). These analyses revealed that the main clay minerals present in our samples are kaolinite, illite and, montmorillonite, with the addition of impurities, the most abundant of which is quartz.展开更多
The acquisition,analysis,and prediction of the radar cross section(RCS)of a target have extremely important strategic significance in the military.However,the RCS values at all azimuths are hardly accessible for non-c...The acquisition,analysis,and prediction of the radar cross section(RCS)of a target have extremely important strategic significance in the military.However,the RCS values at all azimuths are hardly accessible for non-cooperative targets,due to the limitations of radar observation azimuth and detection resources.Despite their efforts to predict the azimuth-dimensional RCS value,traditional methods based on statistical theory fails to achieve the desired results because of the azimuth sensitivity of the target RCS.To address this problem,an improved neural basis expansion analysis for interpretable time series forecasting(N-BEATS)network considering the physical model prior is proposed to predict the azimuth-dimensional RCS value accurately.Concretely,physical model-based constraints are imposed on the network by constructing a scattering-center module based on the target scattering-center model.Besides,a superimposed seasonality module is involved to better capture high-frequency information,and augmenting the training set provides complementary information for learning predictions.Extensive simulations and experimental results are provided to validate the effectiveness of the proposed method.展开更多
With the growth of the construction industry,risk management in construction projects has garnered significant attention from the academic community.Effective risk management during the decision-making stage can great...With the growth of the construction industry,risk management in construction projects has garnered significant attention from the academic community.Effective risk management during the decision-making stage can greatly enhance project management efficiency.This paper integrates the AHP-entropy value method and constructs a risk management model based on the DPSIR framework for construction projects.The model is applied to evaluate and analyze the risk level of the decision-making stage in a navigation and electricity hub project in Chongqing Municipality.The results demonstrate the scientific validity and effectiveness of the proposed model.展开更多
Constructed Wetlands (CWs) are currently one of the most promising techniques for wastewater treatment, having demonstrated their effectiveness. However, the choice of substrate particle size is critical to the smooth...Constructed Wetlands (CWs) are currently one of the most promising techniques for wastewater treatment, having demonstrated their effectiveness. However, the choice of substrate particle size is critical to the smooth operation of the process, as hydrodynamic constraints require a coarse particle size, whereas wastewater treatment recommends a fine particle size. This study investigates the suitability of laterite and shale as substrates of different sizes (1 - 3, 3 - 5 and 5 - 8 mm) in CWs for domestic wastewater treatment. The study was carried out in an experimental pilot plant consisting of 12 parallelepiped beds (C × C = 0.4 × 0.4 m2;H = 0.6 m) filled from bottom to top with 0.1 m of gravel and 0.4 m of shale or laterite of different grain sizes with two replications. During the six months of operation, plant biomass and stem diameter of Pennisetum purpureum used as vegetation in the CWs were determined. Raw and treated water were also sampled and analyzed for pollutants, including chemical oxygen demand (COD), biochemical oxygen demand (BOD5), total Kjedahl nitrogen (TKN), total phosphorus (TP), and total suspended solids (TSS), using International Organization for Standardization (ISO) analytical methods. P. purpureum developed much better in the CW beds lined with shale;plant biomass ranged from 13.8 to 14.7 kg/m2 and from 11.2 to 12.5 kg/m2 in the beds lined with shale and laterite, respectively, as did stump diameter, which ranged from 15.5 to 16.1 cm and from 11.10 to 12.7 cm, respectively. However, the highest values for biomass and stump diameter for each material were obtained in the beds lined with 1 - 3 mm geomaterials. Pollutant removal efficiencies were highest in the CWs lined with laterite and shale of 1 - 3 mm grain size (76.9% - 83% COD, 78% - 84.7% BOD5, 55.5% - 72.2% TKN, 58.4% - 72.4% TP, 78.1% - 80.2% TSS), with the highest values recorded in the shale-lined beds. However, the 3 - 5 mm grain size of both materials provided quality filtrates (140 - 174 mg/L COD, 78.5 - 94.8 mg/L BOD5, 4.6 - 5.7 mg/L TP) in line with local wastewater discharge levels. This size of geomaterials appears to be suitable for optimization purposes, although further work with these materials, such as increasing the depth of the wetland, is required to improve the level of NTK and TSS discharge.展开更多
This study was part of the framework that contributed not only to the improvement of thermal comfort in housing but also to the decarbonization of the construction and building materials industry. For this purpose, te...This study was part of the framework that contributed not only to the improvement of thermal comfort in housing but also to the decarbonization of the construction and building materials industry. For this purpose, terracotta brick seems to meet these needs. Thus, the objective of this work was to evaluate the influence of the incorporation of coal fly ash from a thermal power plant on the physical and mechanical properties of fired bricks from grey clay in the Thicky area of Senegal. The coal fly ash was incorporated into the raw clay material in proportions of 0, 5, 10, and 15 % by weight. These two raw materials were first characterized by X-ray fluorescence spectroscopy (XRF). The XRF analyses showed that the most abundant oxides in clay were SiO2 (55.034%) and Fe2O3 (10.155%). In coal fly ash, SiO2 (38.574%) is predominant. The ash also contained Al2O3 (7.717%) and alicano-earthy melting oxides such as CaO (9.271%) and MgO (7.298%) etc. These melting oxides were necessary to facilitate the formation of the liquid phase when baking platelets. The latter, when burned at a temperature of 880°C, were characterized by determining the number of physico-mechanical parameters, such as linear shrinkage during cooking, water absorption, fire loss and compressive strength. A Hierarchical Ascending Classification of these different parameters was performed and three classes were obtained. Class 1 with better compressive strength (6.358 MPa), was in sample A (5%). Class 2 consisted of sample D (reference) and had a higher plasticity index (28.51%) and water absorption rate (11.19%). Finally, class 3, which included samples B (10%) and C (15%), had very high shrinkage and fire losses compared to other platelets. These results highlighted the possibility of using up to 5% of the coal fly ash in the production of new fired bricks with good performance.展开更多
Purpose–Salt rock from salt lakes can serve as a cost-effective material for subgrade filling,as demonstrated in projects like the Qarhan Salt Lake section of the Qinghai-Tibet Railway and the Qarhan Salt Lake sectio...Purpose–Salt rock from salt lakes can serve as a cost-effective material for subgrade filling,as demonstrated in projects like the Qarhan Salt Lake section of the Qinghai-Tibet Railway and the Qarhan Salt Lake section of the G215 Highway.This state-of-the-art paper aims to summarize the engineering properties of salt rock filling and present the advances of its utilization.Design/methodology/approach–This paper collects and analyzes laboratory and field data of salt rock filling from previous studies to present a comprehensive analysis of the engineering properties and utilization of salt rock fillings.Findings–Salt rock primarily contains minerals such as halite and glauberite,which contribute to its unique phase-changing behavior under varying environmental conditions,impacting its mechanical properties.Salt rock filling shrinks when in contact with vapor or unsaturated brine and expands under cooling or evaporation.Its use is particularly recommended for arid regions,with specific restrictions depending on the structure type.This paper discusses suggested countermeasures to mitigate these issues,as well as key quality acceptance indices for salt rock filling compaction.Moisture content after air-drying is recommended as a crucial parameter for construction quality control.Originality/value–This review aims to support future research and engineering practices in salt rock subgrade applications.展开更多
Purpose–This study is dedicated to systematically collating the distribution and utilization circumstances of geothermal resources in China.Moreover,it endeavors to formulate a comprehensive utilization scheme for ge...Purpose–This study is dedicated to systematically collating the distribution and utilization circumstances of geothermal resources in China.Moreover,it endeavors to formulate a comprehensive utilization scheme for geothermal resources during the construction and operation phases of the railway,thereby furnishing robust support and valuable reference for the holistic utilization of geothermal resources along the railway corridor.Design/methodology/approach–Through an in-depth analysis of the extant utilization of geothermal resources in China,it is discerned that the current utilization modalities are relatively rudimentary,bereft of rational planning and characterized by a low utilization rate.Concurrently,by integrating the practical requisites of railway construction and operation and conducting theoretical dissections,a comprehensive utilization plan for the construction and operation periods of railway is proffered.Findings–In light of the railway’s construction and operation characteristics,geothermal utilization models are categorized.During construction,comprehensive modalities include tunnel illumination power generation,construction area heating,tunnel antifreeze using shallow geothermal energy,tunnel pavement antifreeze and construction concrete maintenance.During operation,they comprise operation tunnel antifreeze,railway roadbed antifreeze,railway switch snow melting and deicing,geothermal power station establishment and railway hot spring health tourism planning.Originality/value–According to the characteristics and actual needs of railway construction and operation,it is of great significance to rationally utilize geothermal resources to promote the construction and operation of green railways.展开更多
Traditional handicrafts,as emblematic representations of cultural heritage,play a crucial role in advancing the cultural construction of schools,facilitating the presentation of traditional culture to contemporary stu...Traditional handicrafts,as emblematic representations of cultural heritage,play a crucial role in advancing the cultural construction of schools,facilitating the presentation of traditional culture to contemporary students in a revitalized manner.This study investigates the implementation path of traditional handicrafts in college development.It encompasses the incorporation of traditional handicrafts into schools,the establishment of a trinity model for cultural education,the formulation of a curriculum that emphasizes the distinctive features of local cultures,the creation of a platform for cultural practice,and the active promotion of school cultural construction.The objective is to foster the creative transformation and innovative advancement of China’s exceptional traditional culture among young students.展开更多
Complex bridge structures designed and constructed by humans often necessitate extensive on-site execution,which carries inherent risks.Consequently,a variety of engineering practices are employed to monitor bridge co...Complex bridge structures designed and constructed by humans often necessitate extensive on-site execution,which carries inherent risks.Consequently,a variety of engineering practices are employed to monitor bridge construction.This paper presents a case study of a large-span prestressed concrete(PC)variable-section continuous girder bridge in China,proposing a feedback system for construction monitoring and establishing a finite element(FE)analysis model for the entire bridge.The alignment of the completed bridge adheres to the initial design expectations,with maximum displacement and pre-arch differences from the ideal state measuring 6.39 and 17.7 mm,respectively,which were less than the 20 mm limit required by the specification.Additionally,the stress monitoring showed that the maximum compressive stress was 10.44 MPa,which was 7.5%different from the finite element results,and better predicted the most unfavorable possible location.These results demonstrate that a scientifically rigorous construction monitoring and feedback system can ensure the safety of bridge construction and meet the expected construction standards.The findings presented in this paper provide valuable insights for bridge construction monitoring practices.展开更多
The cost and strict input format requirements of GraphRAG make it less efficient for processing large documents. This paper proposes an alternative approach for constructing a knowledge graph (KG) from a PDF document ...The cost and strict input format requirements of GraphRAG make it less efficient for processing large documents. This paper proposes an alternative approach for constructing a knowledge graph (KG) from a PDF document with a focus on simplicity and cost-effectiveness. The process involves splitting the document into chunks, extracting concepts within each chunk using a large language model (LLM), and building relationships based on the proximity of concepts in the same chunk. Unlike traditional named entity recognition (NER), which identifies entities like “Shanghai”, the proposed method identifies concepts, such as “Convenient transportation in Shanghai” which is found to be more meaningful for KG construction. Each edge in the KG represents a relationship between concepts occurring in the same text chunk. The process is computationally inexpensive, leveraging locally set up tools like Mistral 7B openorca instruct and Ollama for model inference, ensuring the entire graph generation process is cost-free. A method of assigning weights to relationships, grouping similar pairs, and summarizing multiple relationships into a single edge with associated weight and relation details is introduced. Additionally, node degrees and communities are calculated for node sizing and coloring. This approach offers a scalable, cost-effective solution for generating meaningful knowledge graphs from large documents, achieving results comparable to GraphRAG while maintaining accessibility for personal machines.展开更多
This study first analyzes four distinct forms of Fujian folk dance,highlighting the notable differences in their cultural characteristics and dance qualities.It then categorizes these dance forms to align with textboo...This study first analyzes four distinct forms of Fujian folk dance,highlighting the notable differences in their cultural characteristics and dance qualities.It then categorizes these dance forms to align with textbook construction,discussing in depth the principles guiding the development of textbooks that correspond to these classifications.展开更多
文摘In the oil and gas industry, operations in greenfield sites are straightforward. However, there are increased risks, such as damage to existing facilities, unknown site conditions, and other complexities in brownfield sites. In addition to these physical risks, task scheduling is also complex, as vessels need to be replaced during a turnaround. To mitigate the risks of site conditions and realize a truncated schedule for Saudi Aramco’s operations, 3D laser scanning was combined with 3D modeling, clash detection, and time. This integrated approach minimized the shutdown period, which resulted in cost savings, heightened safety, and enhanced stakeholder communications.
文摘Despite the fact that applying constructability concepts in building designs have led to savings estimated within a range of 1% to 14% of the capital cost, the construction industry still lacks an advanced tool to assess and check for constructability implementations in designs. Therefore, the objective of this research is to propose a quantitative assessment of building constructability, which transforms the subjective assessment of constructability knowledge to a quantified value so that it is easy to analyze and improve building design. The proposed methodology uses the advancement of object oriented Building Information Model (BIM) and 4D simulation model to serve as a data repository models for the constructability assessment platform. Factors affecting constructability of building designs have been identified and relatively weighted using Analytical Hierarchy Process (AHP) technique based on a questionnaire survey collected throughout the Canadian provinces. Evaluation criteria are also developed to assist the designer to evaluate the design proposals. The outcome shows that the proposed method provides the designer an accurate and faster mode in evaluating project constructability by using the parametric features from BIM and taking the advantage of spatial relationship between building components.
基金sponsored by the National Natural Science Foundation of China (Grant Nos.52178299 and 51325802).
文摘Extrudability and constructability are two important,yet contradictory issues pertaining to the construction of three-dimensional(3D)printing concrete.Extrudability is easily achieved when 3D printing cement mortar has a high water content and low cohesion,but the printed structure is easily collapsible.However,a 3D printing cement mortar with a low water content and high cohesion has a relatively stable printed structure although the cement mortar might not be extrudable.This study proposes a particle-based method to simulate 3D printing mortar extrusion and construction as an overall planning tool for building design.First,a discrete element model with time-varying liquid bridge forces is developed to investigate the microscopic effects of these forces on global rheological properties.Next,a series of numerical simulations relevant to 3D printable mortar extrudability and constructability are carried out.The study demonstrates that the effects of time-varying liquid bridge forces on rheological properties and the resulting extrudability and constructability of 3D printing mortar are considerable.Furthermore,an optimized region that satisfies both the extrusion and construction requirements is provided for 3D printing industry as a reference.
基金financially supported by National Key R&D Program of China(2021YFB3500702)National Natural Science Foundation of China(Nos.21677010 and 51808037)Special fund of Beijing Key Laboratory of Indoor Air Quality Evaluation and Control(No.BZ0344KF21-04).
文摘With the ongoing depletion of fossil fuels,energy and environmental issues have become increasingly critical,necessitating the search for effective solutions.Catalysis,being one of the hallmarks of modern industry,offers a promising avenue for researchers.However,the question of how to significantly enhance the performance of catalysts has gradually drawn the attention of scholars.Defect engineering,a commonly employed and effective approach to improve catalyst activity,has become a significant research focus in the catalysis field in recent years.Nonmetal vacancies have received extensive attention due to their simple form.Consequently,exploration of metal vacancies has remained stagnant for a considerable period,resulting in a scarcity of comprehensive reviews on this topic.Therefore,based on the latest research findings,this paper summarizes and consolidates the construction strategies for metal vacancies,characterization techniques,and their roles in typical energy and environmental catalytic reactions.Additionally,it outlines potential challenges in the future,aiming to provide valuable references for researchers interested in investigating metal vacancies.
基金Guizhou Provincial University Humanities and Social Sciences Research Project in 2024"Enhancing the Development of New Productive Forces through University Technological Innovation and Intellectual Property Management"(2024RW256)Guizhou University of Commerce Research Project in 2022"Study on the Ideas and Pathways to Drive Agricultural Powerhouse through Digital Economy"(2022XJZX315)。
文摘With the rapid development of globalization and information technology,intellectual property has been one of the key drivers of economic growth,and the construction of intellectual property system has become an important criterion for measuring the quality of business environment.This article is intended to explore the current status of intellectual property system construction in China,the challenges,and its relationship with the business environment,to propose the corresponding countermeasures and suggestions.The study finds that the legal system of intellectual property in China is gradually improving,and judicial and administrative protection are continuously strengthened.However,the challenges still remain such as frequent infringements,rights hard to protect and insufficient international cooperation.These issues not only affect the legitimate rights and interests of innovation entities,but also for the market fairness and the level of the business environment.Therefore,this article proposes that strengthening the perfection of the intellectual property legal system,enhancing intellectual property services and support capabilities,strengthening international cooperation and exchanges,and accelerating the cultivation of composite talents.It aims to provide theoretical references for the construction of intellectual property system and the optimization of the business environment,promote the high-quality development of economy and enhance the global competitiveness of the country.
文摘Professional and trade skills are required for handling the construction related projects;Construction industries of the present day however lack useful information concerning different practices,patterns and trends involved in risk management.Considering this,the present study focuses on the aforementioned variables of risk management by quantitative analysis specifically in the domain of construction industry.This study has used IBM’s SPSS(Statistical Package for Social Sciences)version 25.0 to analyze the results.This study is an initiative to assess the impact of risk management in the construction sector of Jordan.It will assist the construction sector for exploring the limitations with respect to integrate effective risk management.A sense of competition will be developed through a comparison of risk factors of construction projects among the project stakeholders such as contractors should enhance their risk management practices.
文摘The increasing cost of infrastructure development risks stifling national investment plans.Many projects in Uganda have suffered because of the frequency and magnitude of claims made by parties involved especially the contractors.As a result,the construction industry is plagued with claims which quite often lead to adversarial relationships.The major grounds for claims were identified through studying the contract documents where claims had been made.Increase in scope;change orders;errors in contract documents;inclement weather;inflation;delay in possessing the site;and change in the tax policy were the most prevalent grounds for making claims.Problems identified in claiming process include delays in getting approval;information on claims not reliable;hostility from the parties involved;pricing of claims;delays in effecting payment when approved;and overzealous contract interpretation leading to misunderstanding and delays Using a survey on project managers for 64 contractors and their corresponding clients or their representatives,the major ways in which it can be reduced were identified as being thoroughness during the design phase;providing for inflation;proper planning of works;using prequalified contractors;and proper documentation of records.Clients have a big role to play in reducing claims.
文摘In the process of cultural and tourism project construction,intelligent construction technology has gradually shown strong advantages.The effective application of this technology not only greatly improves the construction efficiency and quality of cultural and tourism projects,but also effectively controls construction costs,laying a solid foundation for the green,low-carbon,and sustainable development of the cultural and tourism industry.The article analyzes the current situation of cultural and tourism project construction,proposes the advantages of intelligent construction and its application in the construction mode of cultural and tourism projects,aiming to provide reliable guidance for the sustainable development of cultural and tourism projects.
文摘The aim of this study is to enhance the value of local earth materials used in the construction of certain homes in the Republic of Guinea. Thus, a trial study to improve the quality of mud bricks using paper fibers obtained by grinding and soaking in water and then drying were used as a stabilizer in the manufacture of these mud bricks from the sample of two sites Dounkiwal (DK) (in Mamou and the sample from the urban commune of Kouroussa). To do this, certain methods and means of identification were carried out, namely: geotechnical, mineralogical and chemical analyses. Sample DK from Mamou has a silty-clay geotechnical characteristic with a plasticity index Ip of 12.75%. However, mineralogical and chemical studies showed that sample Dounkiwal (DK) (Mamou) contains a high proportion of silica and iron oxides (79.63%) and Fe2O3 (11.85%), associated with other alkaline earth oxides and ions: CaO;MgO;SO32−;Cl−, i.e. 3.96%;0.96%;0.28% and 0.039% respectively. Its loss on ignition (LOI) and insoluble residues are 15.40% and 56.36%. The evaluation of the number of huts in Upper and Middle Guinea showed that the populations of these areas have been using mud bricks for several decades in the construction of dwellings. The average value found for the compressive strength of these bricks (from samples I, II and III from Kouroussa) is 0.16 MPa. This value is appreciable in the construction of mud houses.
文摘Clays are a constituent of the earth. As a result, the discovery and traditional use of clays in construction and pottery worldwide dates back to antiquity. Guinea has several deposits of clay minerals whose chemical and mineralogical compositions have been little studied. Despite lacking of scientific data on these clay minerals, they are used today in pottery and habitat construction. As a step towards promoting the use of clay materials in Guinea, we conducted a study of the physicochemical and mineralogical properties of three natural clays from Kakan in the Republic of Guinea (AKKB, AKKE, AKKO) used in habitat construction. The aims of this work were to better understand their properties, but above all to be able to act on them to improve and broaden their applications, which until now have been limited to construction. These clays were studied by X-ray diffraction (XRD), X-ray fluorescence spectrometry (XRF), moisture content (%W), laser granulometry, Atterberg limits, specific surface area, infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), thermogravimetric analysis and differential thermal analysis (TGA/DTA). These analyses revealed that the main clay minerals present in our samples are kaolinite, illite and, montmorillonite, with the addition of impurities, the most abundant of which is quartz.
基金National Natural Science Foundation of China(61921001,62201588,62022091)。
文摘The acquisition,analysis,and prediction of the radar cross section(RCS)of a target have extremely important strategic significance in the military.However,the RCS values at all azimuths are hardly accessible for non-cooperative targets,due to the limitations of radar observation azimuth and detection resources.Despite their efforts to predict the azimuth-dimensional RCS value,traditional methods based on statistical theory fails to achieve the desired results because of the azimuth sensitivity of the target RCS.To address this problem,an improved neural basis expansion analysis for interpretable time series forecasting(N-BEATS)network considering the physical model prior is proposed to predict the azimuth-dimensional RCS value accurately.Concretely,physical model-based constraints are imposed on the network by constructing a scattering-center module based on the target scattering-center model.Besides,a superimposed seasonality module is involved to better capture high-frequency information,and augmenting the training set provides complementary information for learning predictions.Extensive simulations and experimental results are provided to validate the effectiveness of the proposed method.
文摘With the growth of the construction industry,risk management in construction projects has garnered significant attention from the academic community.Effective risk management during the decision-making stage can greatly enhance project management efficiency.This paper integrates the AHP-entropy value method and constructs a risk management model based on the DPSIR framework for construction projects.The model is applied to evaluate and analyze the risk level of the decision-making stage in a navigation and electricity hub project in Chongqing Municipality.The results demonstrate the scientific validity and effectiveness of the proposed model.
文摘Constructed Wetlands (CWs) are currently one of the most promising techniques for wastewater treatment, having demonstrated their effectiveness. However, the choice of substrate particle size is critical to the smooth operation of the process, as hydrodynamic constraints require a coarse particle size, whereas wastewater treatment recommends a fine particle size. This study investigates the suitability of laterite and shale as substrates of different sizes (1 - 3, 3 - 5 and 5 - 8 mm) in CWs for domestic wastewater treatment. The study was carried out in an experimental pilot plant consisting of 12 parallelepiped beds (C × C = 0.4 × 0.4 m2;H = 0.6 m) filled from bottom to top with 0.1 m of gravel and 0.4 m of shale or laterite of different grain sizes with two replications. During the six months of operation, plant biomass and stem diameter of Pennisetum purpureum used as vegetation in the CWs were determined. Raw and treated water were also sampled and analyzed for pollutants, including chemical oxygen demand (COD), biochemical oxygen demand (BOD5), total Kjedahl nitrogen (TKN), total phosphorus (TP), and total suspended solids (TSS), using International Organization for Standardization (ISO) analytical methods. P. purpureum developed much better in the CW beds lined with shale;plant biomass ranged from 13.8 to 14.7 kg/m2 and from 11.2 to 12.5 kg/m2 in the beds lined with shale and laterite, respectively, as did stump diameter, which ranged from 15.5 to 16.1 cm and from 11.10 to 12.7 cm, respectively. However, the highest values for biomass and stump diameter for each material were obtained in the beds lined with 1 - 3 mm geomaterials. Pollutant removal efficiencies were highest in the CWs lined with laterite and shale of 1 - 3 mm grain size (76.9% - 83% COD, 78% - 84.7% BOD5, 55.5% - 72.2% TKN, 58.4% - 72.4% TP, 78.1% - 80.2% TSS), with the highest values recorded in the shale-lined beds. However, the 3 - 5 mm grain size of both materials provided quality filtrates (140 - 174 mg/L COD, 78.5 - 94.8 mg/L BOD5, 4.6 - 5.7 mg/L TP) in line with local wastewater discharge levels. This size of geomaterials appears to be suitable for optimization purposes, although further work with these materials, such as increasing the depth of the wetland, is required to improve the level of NTK and TSS discharge.
文摘This study was part of the framework that contributed not only to the improvement of thermal comfort in housing but also to the decarbonization of the construction and building materials industry. For this purpose, terracotta brick seems to meet these needs. Thus, the objective of this work was to evaluate the influence of the incorporation of coal fly ash from a thermal power plant on the physical and mechanical properties of fired bricks from grey clay in the Thicky area of Senegal. The coal fly ash was incorporated into the raw clay material in proportions of 0, 5, 10, and 15 % by weight. These two raw materials were first characterized by X-ray fluorescence spectroscopy (XRF). The XRF analyses showed that the most abundant oxides in clay were SiO2 (55.034%) and Fe2O3 (10.155%). In coal fly ash, SiO2 (38.574%) is predominant. The ash also contained Al2O3 (7.717%) and alicano-earthy melting oxides such as CaO (9.271%) and MgO (7.298%) etc. These melting oxides were necessary to facilitate the formation of the liquid phase when baking platelets. The latter, when burned at a temperature of 880°C, were characterized by determining the number of physico-mechanical parameters, such as linear shrinkage during cooking, water absorption, fire loss and compressive strength. A Hierarchical Ascending Classification of these different parameters was performed and three classes were obtained. Class 1 with better compressive strength (6.358 MPa), was in sample A (5%). Class 2 consisted of sample D (reference) and had a higher plasticity index (28.51%) and water absorption rate (11.19%). Finally, class 3, which included samples B (10%) and C (15%), had very high shrinkage and fire losses compared to other platelets. These results highlighted the possibility of using up to 5% of the coal fly ash in the production of new fired bricks with good performance.
文摘Purpose–Salt rock from salt lakes can serve as a cost-effective material for subgrade filling,as demonstrated in projects like the Qarhan Salt Lake section of the Qinghai-Tibet Railway and the Qarhan Salt Lake section of the G215 Highway.This state-of-the-art paper aims to summarize the engineering properties of salt rock filling and present the advances of its utilization.Design/methodology/approach–This paper collects and analyzes laboratory and field data of salt rock filling from previous studies to present a comprehensive analysis of the engineering properties and utilization of salt rock fillings.Findings–Salt rock primarily contains minerals such as halite and glauberite,which contribute to its unique phase-changing behavior under varying environmental conditions,impacting its mechanical properties.Salt rock filling shrinks when in contact with vapor or unsaturated brine and expands under cooling or evaporation.Its use is particularly recommended for arid regions,with specific restrictions depending on the structure type.This paper discusses suggested countermeasures to mitigate these issues,as well as key quality acceptance indices for salt rock filling compaction.Moisture content after air-drying is recommended as a crucial parameter for construction quality control.Originality/value–This review aims to support future research and engineering practices in salt rock subgrade applications.
文摘Purpose–This study is dedicated to systematically collating the distribution and utilization circumstances of geothermal resources in China.Moreover,it endeavors to formulate a comprehensive utilization scheme for geothermal resources during the construction and operation phases of the railway,thereby furnishing robust support and valuable reference for the holistic utilization of geothermal resources along the railway corridor.Design/methodology/approach–Through an in-depth analysis of the extant utilization of geothermal resources in China,it is discerned that the current utilization modalities are relatively rudimentary,bereft of rational planning and characterized by a low utilization rate.Concurrently,by integrating the practical requisites of railway construction and operation and conducting theoretical dissections,a comprehensive utilization plan for the construction and operation periods of railway is proffered.Findings–In light of the railway’s construction and operation characteristics,geothermal utilization models are categorized.During construction,comprehensive modalities include tunnel illumination power generation,construction area heating,tunnel antifreeze using shallow geothermal energy,tunnel pavement antifreeze and construction concrete maintenance.During operation,they comprise operation tunnel antifreeze,railway roadbed antifreeze,railway switch snow melting and deicing,geothermal power station establishment and railway hot spring health tourism planning.Originality/value–According to the characteristics and actual needs of railway construction and operation,it is of great significance to rationally utilize geothermal resources to promote the construction and operation of green railways.
基金Sponsored by Humanities and Social Sciences Project of Shandong Federation of Social Sciences“Research on the Communication of Shandong Handicrafts in the Context of New Media”(2023-WHLC-109)General Project of Qingdao Educational Science Planning“Ideological and Political Construction of Public Basic Courses in Higher Vocational Schools in the New Era”(QJK2021C299).
文摘Traditional handicrafts,as emblematic representations of cultural heritage,play a crucial role in advancing the cultural construction of schools,facilitating the presentation of traditional culture to contemporary students in a revitalized manner.This study investigates the implementation path of traditional handicrafts in college development.It encompasses the incorporation of traditional handicrafts into schools,the establishment of a trinity model for cultural education,the formulation of a curriculum that emphasizes the distinctive features of local cultures,the creation of a platform for cultural practice,and the active promotion of school cultural construction.The objective is to foster the creative transformation and innovative advancement of China’s exceptional traditional culture among young students.
基金The Guangdong Basic and Applied Basic Research Foundation(Grant#2023A1515010535).
文摘Complex bridge structures designed and constructed by humans often necessitate extensive on-site execution,which carries inherent risks.Consequently,a variety of engineering practices are employed to monitor bridge construction.This paper presents a case study of a large-span prestressed concrete(PC)variable-section continuous girder bridge in China,proposing a feedback system for construction monitoring and establishing a finite element(FE)analysis model for the entire bridge.The alignment of the completed bridge adheres to the initial design expectations,with maximum displacement and pre-arch differences from the ideal state measuring 6.39 and 17.7 mm,respectively,which were less than the 20 mm limit required by the specification.Additionally,the stress monitoring showed that the maximum compressive stress was 10.44 MPa,which was 7.5%different from the finite element results,and better predicted the most unfavorable possible location.These results demonstrate that a scientifically rigorous construction monitoring and feedback system can ensure the safety of bridge construction and meet the expected construction standards.The findings presented in this paper provide valuable insights for bridge construction monitoring practices.
文摘The cost and strict input format requirements of GraphRAG make it less efficient for processing large documents. This paper proposes an alternative approach for constructing a knowledge graph (KG) from a PDF document with a focus on simplicity and cost-effectiveness. The process involves splitting the document into chunks, extracting concepts within each chunk using a large language model (LLM), and building relationships based on the proximity of concepts in the same chunk. Unlike traditional named entity recognition (NER), which identifies entities like “Shanghai”, the proposed method identifies concepts, such as “Convenient transportation in Shanghai” which is found to be more meaningful for KG construction. Each edge in the KG represents a relationship between concepts occurring in the same text chunk. The process is computationally inexpensive, leveraging locally set up tools like Mistral 7B openorca instruct and Ollama for model inference, ensuring the entire graph generation process is cost-free. A method of assigning weights to relationships, grouping similar pairs, and summarizing multiple relationships into a single edge with associated weight and relation details is introduced. Additionally, node degrees and communities are calculated for node sizing and coloring. This approach offers a scalable, cost-effective solution for generating meaningful knowledge graphs from large documents, achieving results comparable to GraphRAG while maintaining accessibility for personal machines.
文摘This study first analyzes four distinct forms of Fujian folk dance,highlighting the notable differences in their cultural characteristics and dance qualities.It then categorizes these dance forms to align with textbook construction,discussing in depth the principles guiding the development of textbooks that correspond to these classifications.
