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In response to the current issue of poor modeling performance of Building Information Modeling for building models, a new Building Information Modeling based on an improved region growth algorithm is proposed. This method improves the region growth algorithm by introducing machine learning technology, and utilizes the improved algorithm to perfect the building model, thereby improving the efficiency of Building Information Modeling. The performance comparison experiment of the improved algorithm shows that its accuracy is 92.3%, respectively, which are lower than the comparison algorithm. Subsequent empirical analysis found that the robustness rating of the renovated building with the new Building Information Modeling was 94.06, significantly higher than the traditional model. The above results indicate that the new Building Information Modeling proposed in the study has high efficiency and accuracy in building reinforcement and renovation. This method can provide a new solution and idea for the field of building reinforcement and renovation.

Copyright of Railway Construction Technology is the property of Railway Construction Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to solve the problems in the BIM modeling of mountain rail transit tunnels, such as large deviation of tunnel lines, complex tunnel components, low attribute addition efficiency and single presentation effect, this paper presents a mountain rail transit tunnel Geo-BIM modeling method based on Revit+Dynamo+Excel and EVS software. Combined with the characteristics of tunnel linear engineering, the secondary development of Revit's built-in Dynamo plug-in enables fast and accurate parametric modeling of tunnels and batch definition of attribute parameters. This paper proposes a method for establishing a three-dimensional geological body model of a tunnel based on EVS software, and formulates the realization method and standard process of stratigraphic modeling and lithology modeling. Combined with the tunnel BIM model, the visualization of the tunnel construction process is fully realized. Relying on the SHIJIASHAN Tunnel Project, the integration of the BIM model, the GIS surface and the 3D model of the geological body is realized based on the Cesium framework, and the 3D visualization model can be interactively operated with model attributes and data information. Practice shows that the Geo-BIM modeling method can quickly establish the tunnel BIM model and its 3D geological model, and the integrated model information shows a good interaction effect, which has good engineering application value. [ABSTRACT FROM AUTHOR]

At present, the information management of highway construction is still at different levels. Poor information coordination ability. Lack of adequate information technology support. BIM technology is used to realize cooperation and information integration among various disciplines. According to the characteristics of highway construction, this paper constructs the decomposition code of the BIM model by the particle swarm method. This model can better reflect the whole process of highway project cost control characteristics. The corresponding relationship between the “three-level list” and the BIM code is constructed. This paper makes a comprehensive analysis and discussion on the mapping between it and the “item list” in the three types of lists. Thus, BIM can be efficiently connected with the three-level list in the construction of bridge projects. It can better adapt to engineering construction and other engineering management requirements.

In recent years, the rapid advancement of Building Information Modeling (BIM) technology has led to an increasing variety of application scenarios, necessitating diverse demands on the technology. Among these requirements, the lightweighting of BIM models is of paramount importance. However, conventional approaches primarily focus on the models themselves, neglecting the varying needs of users. This study presents a novel lightweighting method for BIM models, starting from user interests or specific scenario requirements. It employs optimized data structures and organization techniques to streamline source data, thereby solving the problem of lightweighting BIM models while catering to the diverse needs of users. A comparison of studies using apartment buildings, office buildings, and commercial complexes as examples show that this method works to greatly enhance the efficiency of visualizing different-sized BIM models in geospatial environments. This research provides a new approach to lightweighting BIM models and holds the promising potential to offer strong technical support for future advancements in BIM technology.

Big data technology continues to catalyze the informatization and intelligence of education and teaching in colleges and universities while accelerating the difficulty of information management. This paper aims to discuss the development and utilization of information resources, as well as security and protection issues in college administration, through the integration of network technology and the college administrative management system. To address the development limitations of administrative management in colleges and universities, this paper proposes key technologies for the construction of intelligent administrative management in these institutions and analyzes the interrelationships between these technologies. The objective of experimental platforms 1 and 2 is to evaluate the ability of BIM models to render buildings of different sizes in real time. Compare the security performance of the fully homomorphic encryption algorithm proposed in this paper and combine the classical encryption algorithms (DES algorithm, AES algorithm, RSA algorithm, ECC algorithm). Examine the students’ perceived attitudes toward intelligence improvements and the overall effectiveness ratings of the school administration staff. The compressed, custom-rendered files used in this paper’s cloud service significantly improve the user experience by reducing the loading time by approximately half. The overall student perception ratings were no less than 4.13, and the effectiveness ratings of faculty and staff were all in the range of 3.5-5.0, indicating that school administration is effective. The intelligent improvement direction and improvement scheme proposed in this paper is feasible and merits further promotion.

To improve the accuracy of predicting the shear bearing capacity of prestressed high-strength concrete beams with web reinforcement, shorten the prediction time, and improve the quality of engineering construction, a BIM model is proposed to predict the shear bearing capacity of prestressed high-strength concrete beams with web reinforcement. For the first time, specimens of prestressed high-strength concrete beams with web reinforcement were made, and their mechanical performance parameters, test points, and loading schemes were determined; Secondly, use the MCT file in Midas Civil to create a finite element model, and then combine the revit parameter model method to establish a BIM based finite element model; Finally, through the data conversion program between the created Revit model and ANSYS, a BIM based mechanical analysis model is generated to predict the shear bearing capacity of prestressed high-strength concrete beams with web reinforcement. The results show that this method can obtain high-quality three-dimensional renderings, with a standard deviation of 0.118 between the predicted shear bearing capacity and the experimental value, and a prediction time of about 0.5 s, which is lower than the expected results. This method has high prediction accuracy and efficiency, which can provide reliable technical reference for construction projects and improve the safety of building structures.

To deeply analyze the performance of paper-cutting elements in interior space design, this paper explores the artistic expression of paper-cutting elements. The BIM model is constructed based on the TVL algorithm, and a noise-reducing style migration method with an additional total variable loss function is used to fuse the texture features of a specific paper-cutting style so that the paper-cutting texture is generated in the target object area more intensively. The algorithm is supplemented with a U-shaped network structure to obtain the mask map of the target object, modify and expand the ScanNet training data set, and input a content map and a style map to generate the stylized paper cutout image automatically. The results show that compared with other elements, the stability of paper-cut elements reaches 96.31%, the image smoothness reaches 89.34%, and the retention of significant regions reaches 93.26%. In modern design, the peak signal-noise of paper-cut elements improved by 13.418d on average, the structural similarity also improved by 0.34807, and the recognition rate of paper-cut elements in the furnishing category reached 95%. Applying paper-cut art in interior space design can give interior furnishing design better visual effects, provide inspiration and ideas for interior space design innovation, and contribute to improving aesthetics.

Copyright of Guangdong Architecture Civil Engineering is the property of Guangdong Architecture Civil Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Railway Standard Design is the property of Railway Standard Design Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of SKEI - International Interdisciplinary Journal / Medunarodni Interdisciplinarni Casopis is the property of University Vitez, Bosnia & Herzegovina and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study investigates the effectiveness of a carbon-fiber-reinforced polymer (CFRP) in enhancing the load-carrying capacity of a steel main girder in a metro station. The objective is to evaluate the applicability of CFRPs in sustaining increases in applied loads and assessing their effectiveness on curved surfaces. Finite element analysis (FEA) identified the most stressed areas of the girder under design loads. Based on the FEA results, a targeted strengthening procedure using CFRP sheets was proposed. Various arrangements of CFRP sheets were tested, including different orientations and thicknesses up to 60% of the girder's flange thickness. To validate the FEA accuracy, two small-scale specimen beams were prepared and tested in the laboratory. One beam was strengthened with CFRP sheets on the tension part of the inner flange side, similar to the suggested strengthening method for the girder. The FEA results show that the CFRP increases stresses by an average of 8% to 10% for the steel main girder, with strengthening effects up to 19% at the center of the CFRP strengthening positions, differing from a regular straight flange shape. Significantly reducing stresses required a total CFRP layer thickness of at least 50% of the flange's total thickness. Applying a CFRP on the inner face of the girder preserves its usability without the need for openings in finishes or the metal deck surface. The findings highlight CFRP's potential to enhance load-carrying capacity on curved surfaces and sustain increased applied loads, offering a promising solution for strengthening infrastructure and similar applications. [ABSTRACT FROM AUTHOR]

Copyright of Water Conservancy Science & Techonlogy & Economy is the property of Water Conservancy Science & Technology & Economy Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Railway Standard Design is the property of Railway Standard Design Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Transportation Science & Technolgy is the property of Transportation Science & Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Technological evolution and BIM have changed the design development process in the construction industry. The operation and maintenance (O&M) phase requires building information throughout its service life, which was previously paper based, making it difficult to carry out maintenance activities. BIM assists in the management, storage, and digital sharing of information generated. However, only part of the information generated is required for the maintenance phase of the building. Although a subset of the IFC schema already exists to describe the data exchange between the BIM model and maintenance software, the data are generic and not well defined according to each the element source of maintenance (ESM). Therefore, through a literature review of existing studies on the use of BIM to support O&M processes, this paper aims to design an information flow to integrate maintenance information into the BIM model. The information is based on six main maintenance acts (inspection, cleaning, proactive measure, correction, replacement, and terms of use) and organized in an external sheet. The building will be divided into ESM according to its function in the building to facilitate the maintenance information flow between sheets and the BIM model. [ABSTRACT FROM AUTHOR]

Publishing BIM standards can facilitate the implementation of BIM construction projects. Their compilation, as in the article, allows to improve them, create or specify requirements. The publication of the international standard ISO 19650 for BIM resulted in numerous revisions to national guidelines. In the aspect of the degrees of detailing of BIM model is visible the development of their definition. Initially, they were divided according to the project phases, over time, into industries, and finally within the types of elements and separately for geometric and alphanumeric information, as well as the attached documentation. ISO 19650 uses the term Level of Information Need. Due to the quantity of global standards in various countries, the article focuses on the Oceania area and ISO 19650. [ABSTRACT FROM AUTHOR]

Copyright of Fly Ash Comprehensive Utilization is the property of Hebei Fly Ash Comprehensive Utilization Magazine Co., Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study investigates the effectiveness of a carbon-fiber-reinforced polymer (CFRP) in enhancing the load-carrying capacity of a steel main girder in a metro station. The objective is to evaluate the applicability of CFRPs in sustaining increases in applied loads and assessing their effectiveness on curved surfaces. Finite element analysis (FEA) identified the most stressed areas of the girder under design loads. Based on the FEA results, a targeted strengthening procedure using CFRP sheets was proposed. Various arrangements of CFRP sheets were tested, including different orientations and thicknesses up to 60% of the girder’s flange thickness. To validate the FEA accuracy, two small-scale specimen beams were prepared and tested in the laboratory. One beam was strengthened with CFRP sheets on the tension part of the inner flange side, similar to the suggested strengthening method for the girder. The FEA results show that the CFRP increases stresses by an average of 8% to 10% for the steel main girder, with strengthening effects up to 19% at the center of the CFRP strengthening positions, differing from a regular straight flange shape. Significantly reducing stresses required a total CFRP layer thickness of at least 50% of the flange’s total thickness. Applying a CFRP on the inner face of the girder preserves its usability without the need for openings in finishes or the metal deck surface. The findings highlight CFRP’s potential to enhance load-carrying capacity on curved surfaces and sustain increased applied loads, offering a promising solution for strengthening infrastructure and similar applications.

Waterway engineering has the characteristics of long construction period, scattered space and many influencing factors. Therefore, it is difficult for traditional construction management systems to achieve rapid adjustment and delivery when faced with changing engineering needs. In order to solve problem of rapid development and delivery, the different businesses in the design, construction and maintenance stages of waterway engineering were fully decoupled. Based on the characteristics of multi service isolation of micro service architecture, taking micro service as the smallest unit of each business module, the BIM integrated management platform of waterway engineering was finally designed and implemented, which provides an efficient means for the life cycle management of waterway engineering. [ABSTRACT FROM AUTHOR]

This article deals with the cost estimating of building constructions in BIM 5D. First, the main features of BIM 5D such as Autodesk Revit1 (BIM modelling software), DESK building library, BIM DEKSOFT, or budgeting software KROS 4 are introduced and further described. Then, the article analysis a BIM model based on an architectural plan of a family house. The main aim of this article is to compare a budget of the family house generated budget by BIM 5D with a budget prepared by the authors. Chiefly, the article focuses on the differences in schedule of works, bill of quantities, and costs.

In recent years, various geological environmental disasters and urban accidents have occurred frequently. The existing dynamic planning of rescue routes for refuge buildings does not take the spatial environment layout into consideration. Therefore, in this paper, we apply the concept of symmetrical inverse layout merger to the rescue path dynamic planning of refuge buildings, and design a method for the rescue path dynamic planning of refuge buildings based on symmetrical inverse layout merger. First, based on the symmetric inverse layout merging algorithm, the spatial environment planning features of the refuge building are extracted. The input of the algorithm is the spatial image queue of the refuge building, and the output is the spatial planning feature image queue of the refuge building. Revit modeling software is used to build the refuge building BIM model, which includes the construction of refuge building floor slabs, stairs, walls, windows, doors, columns, slabs, internal beams and other structural parts models. For the constructed refuge building BIM model, the spatial structure of the refuge building is divided by the grid identification method, and grid nodes are used to represent the actual spatial layout of the refuge building. Furthermore, the ant colony algorithm is used to realize the dynamic planning of refuge building rescue path. Finally, the method was compared with the fire evacuation time of the two existing methods, and the experimental results proved that the method has the lowest time for complete evacuation from the fire, which achieves the purpose of reducing rescue time. [ABSTRACT FROM AUTHOR]

This paper mainly focuses on the development of risk assessment plug-in for BIM model of mine tunneling method. Firstly, Dynamo was used to build a 3D model of a certain section of Beijing Gaoliying Tunnel, and on this basis, the geological risk assessment software and Navisworks plug -in were developed by using C# language. Combined with the results of finite element numerical analysis based on Hoek -Brown failure criterion, The display functions of risk assessment, field photos, advanced geological prediction, simulation analysis and detection data were realized in the BIM model, so as to strengthen the expansion and application function of BIM model information. [ABSTRACT FROM AUTHOR]

The use of BIM technology can effectively improve the production efficiency and engineering quality of prefabricated buildings, connect the original scattered and independent enterprises to each other, change the traditional construction method, and truly realize the industrialization by informationization and effectively improve the building. Difficulties in resource consumption and uneven distribution during the construction process improve the quality and efficiency of the project. The purpose of this article is to use the BIM model to observe and analyze the dynamic data of nano-modified new building steel structural materials, and analyze the dynamic data of the nano-modified new building steel structural materials. The influence of new building steel structure materials on the comparison of building information data before and after, researches the dynamic data monitoring of building information of nano-modified new building steel structure materials using BIM model. Using the method of this paper, through the analysis of experimental data, the role of nano-modified new building steel structural materials was understood, and it was found that nano-modified new building steel structural materials play an important role in construction, and the satisfaction rate reaches 60%. Through theoretical and experimental data Combined, it analyzes that the use of BIM model for the dynamic data monitoring research of nano-modification new construction steel structure materials has a research effect of 47%. The research results show that nano-modification new construction steel structure materials have an important role in building information and can be used in Build a natural and harmonious symbiotic building with Chinese characteristics. [ABSTRACT FROM AUTHOR]

Automatic reality capture and monitoring of construction sites can reduce costs, accelerate timelines and improve quality in construction projects. Recently, automatic close-range capture of the state of large construction sites has become possible through crane and drone-mounted cameras, which results in sizeable, noisy, multi-building as-built point clouds. To infer construction progress from these point clouds, they must be aligned with the as-designed BIM model. Unlike the problem of aligning single buildings, the multi-building scenario is not well-studied. In this work, we address some unique issues that arise in the alignment of multi-building point clouds. Firstly, we show that a BIM-based 3D filter is a versatile tool that can be used at multiple stages of the alignment process. We use the building-pass filter to remove non-building noise and thus extract the buildings, delineate the boundaries of the building after the base is identified and as a post-processing step after the alignment is achieved. Secondly, in light of the sparseness of some buildings due to partial capture, we propose to use the best-captured building as a pivot to align the entire point cloud. We propose a fully automated three-step alignment process that leverages the simple geometry of the pivot building and aligns partial xy-projections, identifies the base using z-histograms and aligns the bounding boxes of partial yz-projections. Experimental results with crane camera point clouds of a large construction site show that our proposed techniques are fast and accurate, allowing us to estimate the current floor under construction from the aligned clouds and enabling potential slab state analysis. This work contributes a fully automated method of reality capture and monitoring of multi-building construction sites.

According to the current situation of informatization in the field of marine engineering in China, this paper puts forward the idea of applying BIM technology (building information model) to implement BLM (building engineering life cycle management) system in the stage of design, construction, operation, and maintenance, so as to improve the core competitiveness of enterprises more quickly. BIM has powerful visualization and information integration ability, combines BIM with health monitoring, provides a good expression environment for monitoring information, and improves the interaction between monitoring information and BIM model. The experimental results show that the song fairy bridge detection in ocean engineering projects, the use of Revit structures, project structure, and the software sensor model, using visual warning based on BIM plug-in and data management platform, has realized the data view, view and data management, automatic warning, monitoring curve in this paper; the proposed method was verified and applied in practical engineering projects. [ABSTRACT FROM AUTHOR]

The use of Unmanned Aerial Vehicles (UAV) and drones has increased in recent years in the construction industry. The progress in technology in the design and navigation of low-weight and autonomous drones and UAVs allowed for a cost-effective and more practical operation in construction management and monitoring [1]. An innovative automated construction monitoring and reporting framework, based on real-time data obtained from UAVs are developed, the data will be collected from multiple locations and point clouds used to construct a 3D model using photogrammetry techniques [2]. This new model obtained from drone images can be compared to the BIM model at various construction stages to monitor the construction progress. Besides construction scheduling and costing, this comparison can include real-time recording, reporting, billing, verification, and planning. With the obtained automated system, a significant reduction of the effort required can be observed compared to more traditional methods, resulting in better operations, planning and effective on-site adjustments. [ABSTRACT FROM AUTHOR]

Copyright of Guangdong Architecture Civil Engineering is the property of Guangdong Architecture Civil Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

To improve the accuracy of predicting the shear bearing capacity of prestressed high-strength concrete beams with web reinforcement, shorten the prediction time, and improve the quality of engineering construction, a BIM model is proposed to predict the shear bearing capacity of prestressed high-strength concrete beams with web reinforcement. For the first time, specimens of prestressed high-strength concrete beams with web reinforcement were made, and their mechanical performance parameters, test points, and loading schemes were determined; Secondly, use the MCT file in Midas Civil to create a finite element model, and then combine the revit parameter model method to establish a BIM based finite element model; Finally, through the data conversion program between the created Revit model and ANSYS, a BIM based mechanical analysis model is generated to predict the shear bearing capacity of prestressed high-strength concrete beams with web reinforcement. The results show that this method can obtain high-quality three-dimensional renderings, with a standard deviation of 0.118 between the predicted shear bearing capacity and the experimental value, and a prediction time of about 0.5 s, which is lower than the expected results. This method has high prediction accuracy and efficiency, which can provide reliable technical reference for construction projects and improve the safety of building structures. [ABSTRACT FROM AUTHOR]

In order to reduce the influence of upstream buildings on street valley pollution, an analysis of the influence of upstream buildings on the distribution of pollutants in street canyons based on three-dimensional BIM model is proposed. Based on the three-dimensional BIM model, the street valley of four building layout planes is given, and the height of the buildings on the two sides of the street valley is analyzed by numerical simulation and is 15m. The numerical simulation uses FLUENT-6.3.26 as the basic program to simulate the velocity of air flow and the concentration field of pollutants in the solution area. The diffusion equation of pollutants is represented by QUICK scheme. The experimental results show that the swirl in the middle street valley of layout 3 is beneficial to the diffusion of pollutants. [ABSTRACT FROM AUTHOR]

Copyright of China Mechanical Engineering is the property of Editorial Board of China Mechanical Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

With the continuous development of social and economic level, people's demand for cities is gradually rising, and various natural landscapes emerge as the times require. River landscape has attracted great attention for its effective utilization of river. The changes of climate, vegetation and land use pattern in river basin play a decisive role in the ecological water demand of river landscape. Taking a river basin area as an example, the current river landscape ecological water demand was estimated, and the river ecological water demand at different levels and different guaranteed rates was predicted by using the watershed distribution hydrological model SWAT. The results show that the current annual ecological water demand of river landscape is 81.09×106 m3, and the self-purification water demand is an important part of the river ecological water demand. Therefore, the key to ensure the ecological water demand of a river basin is pollution control. Through further control of pollutant, it is predicted that the ecological water demand of river landscape will decrease continuously in 2019, 2020, and 2030. The natural runoff of river can meet the ecological water demand of river landscape in flood years, but serious ecological deficiency will occur in dry years, which requires ecological water replenishment of river. [ABSTRACT FROM AUTHOR]

Information technology is becoming a strong tool in different industries, including construction. The recent trend of buildings designing is leading up to creation of the most comprehensive virtual building model (Building Information Model) in order to solve all the problems relating to the project as early as in the designing phase. Building information modelling is a new way of approaching to the design of building projects documentation. Currently, the building site layout as a part of the building design documents has a very little support in the BIM environment. Recently, the research of designing the construction process conditions has centred on improvement of general practice in planning and on new approaches to construction site layout planning. The state of art in field of designing the construction process conditions indicated an unexplored problem related to connection of knowledge system with construction site facilities (CSF) layout through interactive modelling. The goal of the paper is to present the methodology for execution of 3D construction site facility allocation model (3D CSF-IAM), based on principles of parametric and interactive modelling.

Copyright of Guangdong Architecture Civil Engineering is the property of Guangdong Architecture Civil Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)